refactor(config): rewrite config parser

This PR refactors the configuration parser, replacing the old parser implementation with a new, more structured approach that includes validation and improved organization.

Key changes:
- Complete rewrite of the configuration parser using a map-based structure with built-in validation
- Addition of comprehensive validator functions for configuration values
- Renamed numerous configuration getter methods for better consistency

internal/cli/cli.go

@@ -78,7 +78,7 @@ func Parse() {
 	flag.StringVar(&flagExportUserFeeds, "export-user-feeds", "", flagExportUserFeedsHelp)
 	flag.Parse()
 
-	cfg := config.NewParser()
+	cfg := config.NewConfigParser()
 
 	if flagConfigFile != "" {
 		config.Opts, err = cfg.ParseFile(flagConfigFile)

internal/config/config.go

@@ -0,0 +1,11 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package config // import "miniflux.app/v2/internal/config"
+
+import "miniflux.app/v2/internal/version"
+
+// Opts holds parsed configuration options.
+var Opts *configOptions
+
+var defaultHTTPClientUserAgent = "Mozilla/5.0 (compatible; Miniflux/" + version.Version + "; +https://miniflux.app)"

internal/config/parser.go

@@ -7,7 +7,6 @@ import (
 	"bufio"
 	"bytes"
 	"crypto/rand"
-	"errors"
 	"fmt"
 	"io"
 	"net/url"
@@ -17,301 +16,205 @@ import (
 	"time"
 )
 
-// parser handles configuration parsing.
+type configParser struct {
-type parser struct {
+	options *configOptions
-	opts *options
 }
 
-// NewParser returns a new Parser.
+func NewConfigParser() *configParser {
-func NewParser() *parser {
+	return &configParser{
-	return &parser{
+		options: NewConfigOptions(),
-		opts: NewOptions(),
 	}
 }
 
-// ParseEnvironmentVariables loads configuration values from environment variables.
+func (cp *configParser) ParseEnvironmentVariables() (*configOptions, error) {
-func (p *parser) ParseEnvironmentVariables() (*options, error) {
+	if err := cp.parseLines(os.Environ()); err != nil {
-	err := p.parseLines(os.Environ())
-	if err != nil {
 		return nil, err
 	}
-	return p.opts, nil
+
+	return cp.options, nil
 }
 
-// ParseFile loads configuration values from a local file.
+func (cp *configParser) ParseFile(filename string) (*configOptions, error) {
-func (p *parser) ParseFile(filename string) (*options, error) {
 	fp, err := os.Open(filename)
 	if err != nil {
 		return nil, err
 	}
 	defer fp.Close()
 
-	err = p.parseLines(p.parseFileContent(fp))
+	if err := cp.parseLines(parseFileContent(fp)); err != nil {
-	if err != nil {
 		return nil, err
 	}
-	return p.opts, nil
+
+	return cp.options, nil
 }
 
-func (p *parser) parseFileContent(r io.Reader) (lines []string) {
+func (cp *configParser) postParsing() error {
-	scanner := bufio.NewScanner(r)
+	// Parse basePath and rootURL based on BASE_URL
-	for scanner.Scan() {
+	baseURL := cp.options.options["BASE_URL"].ParsedStringValue
-		line := strings.TrimSpace(scanner.Text())
+	baseURL = strings.TrimSuffix(baseURL, "/")
-		if !strings.HasPrefix(line, "#") && strings.Index(line, "=") > 0 {
-			lines = append(lines, line)
-		}
-	}
-	return lines
-}
 
-func (p *parser) parseLines(lines []string) (err error) {
+	parsedURL, err := url.Parse(baseURL)
-	var port string
-
-	for lineNum, line := range lines {
-		key, value, ok := strings.Cut(line, "=")
-		if !ok {
-			return fmt.Errorf("config: unable to parse configuration, invalid format on line %d", lineNum)
-		}
-		key, value = strings.TrimSpace(key), strings.TrimSpace(value)
-
-		switch key {
-		case "LOG_FILE":
-			p.opts.logFile = parseString(value, defaultLogFile)
-		case "LOG_DATE_TIME":
-			p.opts.logDateTime = parseBool(value, defaultLogDateTime)
-		case "LOG_LEVEL":
-			parsedValue := parseString(value, defaultLogLevel)
-			if parsedValue == "debug" || parsedValue == "info" || parsedValue == "warning" || parsedValue == "error" {
-				p.opts.logLevel = parsedValue
-			}
-		case "LOG_FORMAT":
-			parsedValue := parseString(value, defaultLogFormat)
-			if parsedValue == "json" || parsedValue == "text" {
-				p.opts.logFormat = parsedValue
-			}
-		case "BASE_URL":
-			p.opts.baseURL, p.opts.rootURL, p.opts.basePath, err = parseBaseURL(value)
-			if err != nil {
-				return err
-			}
-		case "PORT":
-			port = value
-		case "LISTEN_ADDR":
-			p.opts.listenAddr = parseStringList(value, []string{defaultListenAddr})
-		case "DATABASE_URL":
-			p.opts.databaseURL = parseString(value, defaultDatabaseURL)
-		case "DATABASE_URL_FILE":
-			p.opts.databaseURL = readSecretFile(value, defaultDatabaseURL)
-		case "DATABASE_MAX_CONNS":
-			p.opts.databaseMaxConns = parseInt(value, defaultDatabaseMaxConns)
-		case "DATABASE_MIN_CONNS":
-			p.opts.databaseMinConns = parseInt(value, defaultDatabaseMinConns)
-		case "DATABASE_CONNECTION_LIFETIME":
-			p.opts.databaseConnectionLifetime = parseInt(value, defaultDatabaseConnectionLifetime)
-		case "FILTER_ENTRY_MAX_AGE_DAYS":
-			p.opts.filterEntryMaxAgeDays = parseInt(value, defaultFilterEntryMaxAgeDays)
-		case "RUN_MIGRATIONS":
-			p.opts.runMigrations = parseBool(value, defaultRunMigrations)
-		case "DISABLE_HSTS":
-			p.opts.hsts = !parseBool(value, defaultHSTS)
-		case "HTTPS":
-			p.opts.HTTPS = parseBool(value, defaultHTTPS)
-		case "DISABLE_SCHEDULER_SERVICE":
-			p.opts.schedulerService = !parseBool(value, defaultSchedulerService)
-		case "DISABLE_HTTP_SERVICE":
-			p.opts.httpService = !parseBool(value, defaultHTTPService)
-		case "CERT_FILE":
-			p.opts.certFile = parseString(value, defaultCertFile)
-		case "KEY_FILE":
-			p.opts.certKeyFile = parseString(value, defaultKeyFile)
-		case "CERT_DOMAIN":
-			p.opts.certDomain = parseString(value, defaultCertDomain)
-		case "CLEANUP_FREQUENCY_HOURS":
-			p.opts.cleanupFrequencyInterval = parseInterval(value, time.Hour, defaultCleanupFrequency)
-		case "CLEANUP_ARCHIVE_READ_DAYS":
-			p.opts.cleanupArchiveReadInterval = parseInterval(value, 24*time.Hour, defaultCleanupArchiveReadInterval)
-		case "CLEANUP_ARCHIVE_UNREAD_DAYS":
-			p.opts.cleanupArchiveUnreadInterval = parseInterval(value, 24*time.Hour, defaultCleanupArchiveUnreadInterval)
-		case "CLEANUP_ARCHIVE_BATCH_SIZE":
-			p.opts.cleanupArchiveBatchSize = parseInt(value, defaultCleanupArchiveBatchSize)
-		case "CLEANUP_REMOVE_SESSIONS_DAYS":
-			p.opts.cleanupRemoveSessionsInterval = parseInterval(value, 24*time.Hour, defaultCleanupRemoveSessionsInterval)
-		case "WORKER_POOL_SIZE":
-			p.opts.workerPoolSize = parseInt(value, defaultWorkerPoolSize)
-		case "FORCE_REFRESH_INTERVAL":
-			p.opts.forceRefreshInterval = parseInterval(value, time.Minute, defaultForceRefreshInterval)
-		case "BATCH_SIZE":
-			p.opts.batchSize = parseInt(value, defaultBatchSize)
-		case "POLLING_FREQUENCY":
-			p.opts.pollingFrequency = parseInterval(value, time.Minute, defaultPollingFrequency)
-		case "POLLING_LIMIT_PER_HOST":
-			p.opts.pollingLimitPerHost = parseInt(value, 0)
-		case "POLLING_PARSING_ERROR_LIMIT":
-			p.opts.pollingParsingErrorLimit = parseInt(value, defaultPollingParsingErrorLimit)
-		case "POLLING_SCHEDULER":
-			p.opts.pollingScheduler = strings.ToLower(parseString(value, defaultPollingScheduler))
-		case "SCHEDULER_ENTRY_FREQUENCY_MAX_INTERVAL":
-			p.opts.schedulerEntryFrequencyMaxInterval = parseInterval(value, time.Minute, defaultSchedulerEntryFrequencyMaxInterval)
-		case "SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL":
-			p.opts.schedulerEntryFrequencyMinInterval = parseInterval(value, time.Minute, defaultSchedulerEntryFrequencyMinInterval)
-		case "SCHEDULER_ENTRY_FREQUENCY_FACTOR":
-			p.opts.schedulerEntryFrequencyFactor = parseInt(value, defaultSchedulerEntryFrequencyFactor)
-		case "SCHEDULER_ROUND_ROBIN_MIN_INTERVAL":
-			p.opts.schedulerRoundRobinMinInterval = parseInterval(value, time.Minute, defaultSchedulerRoundRobinMinInterval)
-		case "SCHEDULER_ROUND_ROBIN_MAX_INTERVAL":
-			p.opts.schedulerRoundRobinMaxInterval = parseInterval(value, time.Minute, defaultSchedulerRoundRobinMaxInterval)
-		case "MEDIA_PROXY_HTTP_CLIENT_TIMEOUT":
-			p.opts.mediaProxyHTTPClientTimeout = parseInterval(value, time.Second, defaultMediaProxyHTTPClientTimeout)
-		case "MEDIA_PROXY_MODE":
-			p.opts.mediaProxyMode = parseString(value, defaultMediaProxyMode)
-		case "MEDIA_PROXY_RESOURCE_TYPES":
-			p.opts.mediaProxyResourceTypes = parseStringList(value, []string{defaultMediaResourceTypes})
-		case "MEDIA_PROXY_PRIVATE_KEY":
-			randomKey := make([]byte, 16)
-			rand.Read(randomKey)
-			p.opts.mediaProxyPrivateKey = parseBytes(value, randomKey)
-		case "MEDIA_PROXY_CUSTOM_URL":
-			p.opts.mediaProxyCustomURL, err = url.Parse(parseString(value, defaultMediaProxyURL))
-			if err != nil {
-				return fmt.Errorf("config: invalid MEDIA_PROXY_CUSTOM_URL value: %w", err)
-			}
-		case "CREATE_ADMIN":
-			p.opts.createAdmin = parseBool(value, defaultCreateAdmin)
-		case "ADMIN_USERNAME":
-			p.opts.adminUsername = parseString(value, defaultAdminUsername)
-		case "ADMIN_USERNAME_FILE":
-			p.opts.adminUsername = readSecretFile(value, defaultAdminUsername)
-		case "ADMIN_PASSWORD":
-			p.opts.adminPassword = parseString(value, defaultAdminPassword)
-		case "ADMIN_PASSWORD_FILE":
-			p.opts.adminPassword = readSecretFile(value, defaultAdminPassword)
-		case "OAUTH2_USER_CREATION":
-			p.opts.oauth2UserCreationAllowed = parseBool(value, defaultOAuth2UserCreation)
-		case "OAUTH2_CLIENT_ID":
-			p.opts.oauth2ClientID = parseString(value, defaultOAuth2ClientID)
-		case "OAUTH2_CLIENT_ID_FILE":
-			p.opts.oauth2ClientID = readSecretFile(value, defaultOAuth2ClientID)
-		case "OAUTH2_CLIENT_SECRET":
-			p.opts.oauth2ClientSecret = parseString(value, defaultOAuth2ClientSecret)
-		case "OAUTH2_CLIENT_SECRET_FILE":
-			p.opts.oauth2ClientSecret = readSecretFile(value, defaultOAuth2ClientSecret)
-		case "OAUTH2_REDIRECT_URL":
-			p.opts.oauth2RedirectURL = parseString(value, defaultOAuth2RedirectURL)
-		case "OAUTH2_OIDC_DISCOVERY_ENDPOINT":
-			p.opts.oidcDiscoveryEndpoint = parseString(value, defaultOAuth2OidcDiscoveryEndpoint)
-		case "OAUTH2_OIDC_PROVIDER_NAME":
-			p.opts.oidcProviderName = parseString(value, defaultOauth2OidcProviderName)
-		case "OAUTH2_PROVIDER":
-			p.opts.oauth2Provider = parseString(value, defaultOAuth2Provider)
-		case "DISABLE_LOCAL_AUTH":
-			p.opts.disableLocalAuth = parseBool(value, defaultDisableLocalAuth)
-		case "HTTP_CLIENT_TIMEOUT":
-			p.opts.httpClientTimeout = parseInterval(value, time.Second, defaultHTTPClientTimeout)
-		case "HTTP_CLIENT_MAX_BODY_SIZE":
-			p.opts.httpClientMaxBodySize = int64(parseInt(value, defaultHTTPClientMaxBodySize) * 1024 * 1024)
-		case "HTTP_CLIENT_PROXY":
-			p.opts.httpClientProxyURL, err = url.Parse(parseString(value, defaultHTTPClientProxy))
-			if err != nil {
-				return fmt.Errorf("config: invalid HTTP_CLIENT_PROXY value: %w", err)
-			}
-		case "HTTP_CLIENT_PROXIES":
-			p.opts.httpClientProxies = parseStringList(value, []string{})
-		case "HTTP_CLIENT_USER_AGENT":
-			p.opts.httpClientUserAgent = parseString(value, defaultHTTPClientUserAgent)
-		case "HTTP_SERVER_TIMEOUT":
-			p.opts.httpServerTimeout = parseInterval(value, time.Second, defaultHTTPServerTimeout)
-		case "AUTH_PROXY_HEADER":
-			p.opts.authProxyHeader = parseString(value, defaultAuthProxyHeader)
-		case "AUTH_PROXY_USER_CREATION":
-			p.opts.authProxyUserCreation = parseBool(value, defaultAuthProxyUserCreation)
-		case "MAINTENANCE_MODE":
-			p.opts.maintenanceMode = parseBool(value, defaultMaintenanceMode)
-		case "MAINTENANCE_MESSAGE":
-			p.opts.maintenanceMessage = parseString(value, defaultMaintenanceMessage)
-		case "METRICS_COLLECTOR":
-			p.opts.metricsCollector = parseBool(value, defaultMetricsCollector)
-		case "METRICS_REFRESH_INTERVAL":
-			p.opts.metricsRefreshInterval = parseInterval(value, time.Second, defaultMetricsRefreshInterval)
-		case "METRICS_ALLOWED_NETWORKS":
-			p.opts.metricsAllowedNetworks = parseStringList(value, []string{defaultMetricsAllowedNetworks})
-		case "METRICS_USERNAME":
-			p.opts.metricsUsername = parseString(value, defaultMetricsUsername)
-		case "METRICS_USERNAME_FILE":
-			p.opts.metricsUsername = readSecretFile(value, defaultMetricsUsername)
-		case "METRICS_PASSWORD":
-			p.opts.metricsPassword = parseString(value, defaultMetricsPassword)
-		case "METRICS_PASSWORD_FILE":
-			p.opts.metricsPassword = readSecretFile(value, defaultMetricsPassword)
-		case "FETCH_BILIBILI_WATCH_TIME":
-			p.opts.fetchBilibiliWatchTime = parseBool(value, defaultFetchBilibiliWatchTime)
-		case "FETCH_NEBULA_WATCH_TIME":
-			p.opts.fetchNebulaWatchTime = parseBool(value, defaultFetchNebulaWatchTime)
-		case "FETCH_ODYSEE_WATCH_TIME":
-			p.opts.fetchOdyseeWatchTime = parseBool(value, defaultFetchOdyseeWatchTime)
-		case "FETCH_YOUTUBE_WATCH_TIME":
-			p.opts.fetchYouTubeWatchTime = parseBool(value, defaultFetchYouTubeWatchTime)
-		case "YOUTUBE_API_KEY":
-			p.opts.youTubeApiKey = parseString(value, defaultYouTubeApiKey)
-		case "YOUTUBE_EMBED_URL_OVERRIDE":
-			p.opts.youTubeEmbedUrlOverride = parseString(value, defaultYouTubeEmbedUrlOverride)
-		case "WATCHDOG":
-			p.opts.watchdog = parseBool(value, defaultWatchdog)
-		case "INVIDIOUS_INSTANCE":
-			p.opts.invidiousInstance = parseString(value, defaultInvidiousInstance)
-		case "WEBAUTHN":
-			p.opts.webAuthn = parseBool(value, defaultWebAuthn)
-		}
-	}
-
-	if port != "" {
-		p.opts.listenAddr = []string{":" + port}
-	}
-
-	youtubeEmbedURL, err := url.Parse(p.opts.youTubeEmbedUrlOverride)
 	if err != nil {
-		return fmt.Errorf("config: invalid YOUTUBE_EMBED_URL_OVERRIDE value: %w", err)
+		return fmt.Errorf("invalid BASE_URL: %v", err)
-	}
-	p.opts.youTubeEmbedDomain = youtubeEmbedURL.Hostname()
-
-	return nil
-}
-
-func parseBaseURL(value string) (string, string, string, error) {
-	if value == "" {
-		return defaultBaseURL, defaultRootURL, "", nil
-	}
-
-	value = strings.TrimSuffix(value, "/")
-
-	parsedURL, err := url.Parse(value)
-	if err != nil {
-		return "", "", "", fmt.Errorf("config: invalid BASE_URL: %w", err)
 	}
 
 	scheme := strings.ToLower(parsedURL.Scheme)
 	if scheme != "https" && scheme != "http" {
-		return "", "", "", errors.New("config: invalid BASE_URL: scheme must be http or https")
+		return fmt.Errorf("BASE_URL scheme must be http or https")
 	}
 
-	basePath := parsedURL.Path
+	cp.options.options["BASE_URL"].ParsedStringValue = baseURL
+	cp.options.basePath = parsedURL.Path
+
 	parsedURL.Path = ""
-	return value, parsedURL.String(), basePath, nil
+	cp.options.rootURL = parsedURL.String()
+
+	// Parse YouTube embed domain based on YOUTUBE_EMBED_URL_OVERRIDE
+	youTubeEmbedURLOverride := cp.options.options["YOUTUBE_EMBED_URL_OVERRIDE"].ParsedStringValue
+	if youTubeEmbedURLOverride != "" {
+		parsedYouTubeEmbedURL, err := url.Parse(youTubeEmbedURLOverride)
+		if err != nil {
+			return fmt.Errorf("invalid YOUTUBE_EMBED_URL_OVERRIDE: %v", err)
+		}
+		cp.options.youTubeEmbedDomain = parsedYouTubeEmbedURL.Hostname()
+	}
+
+	// Generate a media proxy private key if not set
+	if len(cp.options.options["MEDIA_PROXY_PRIVATE_KEY"].ParsedBytesValue) == 0 {
+		randomKey := make([]byte, 16)
+		rand.Read(randomKey)
+		cp.options.options["MEDIA_PROXY_PRIVATE_KEY"].ParsedBytesValue = randomKey
+	}
+
+	// Override LISTEN_ADDR with PORT if set (for compatibility reasons)
+	if cp.options.Port() != "" {
+		cp.options.options["LISTEN_ADDR"].ParsedStringList = []string{":" + cp.options.Port()}
+		cp.options.options["LISTEN_ADDR"].RawValue = ":" + cp.options.Port()
+	}
+
+	return nil
 }
 
-func parseBool(value string, fallback bool) bool {
+func (cp *configParser) parseLines(lines []string) error {
+	for lineNum, line := range lines {
+		key, value, ok := strings.Cut(line, "=")
+		if !ok {
+			return fmt.Errorf("unable to parse configuration, invalid format on line %d", lineNum)
+		}
+
+		key, value = strings.TrimSpace(key), strings.TrimSpace(value)
+		if err := cp.parseLine(key, value); err != nil {
+			return err
+		}
+	}
+
+	if err := cp.postParsing(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (cp *configParser) parseLine(key, value string) error {
+	field, exists := cp.options.options[key]
+	if !exists {
+		// Ignore unknown configuration keys to avoid parsing unrelated environment variables.
+		return nil
+	}
+
+	// Validate the option if a validator is provided
+	if field.Validator != nil {
+		if err := field.Validator(value); err != nil {
+			return fmt.Errorf("invalid value for key %s: %v", key, err)
+		}
+	}
+
+	// Convert the raw value based on its type
+	switch field.ValueType {
+	case stringType:
+		field.ParsedStringValue = parseStringValue(value, field.ParsedStringValue)
+		field.RawValue = value
+	case stringListType:
+		field.ParsedStringList = parseStringListValue(value, field.ParsedStringList)
+		field.RawValue = value
+	case boolType:
+		parsedValue, err := parseBoolValue(value, field.ParsedBoolValue)
+		if err != nil {
+			return fmt.Errorf("invalid boolean value for key %s: %v", key, err)
+		}
+		field.ParsedBoolValue = parsedValue
+		field.RawValue = value
+	case intType:
+		field.ParsedIntValue = parseIntValue(value, field.ParsedIntValue)
+		field.RawValue = value
+	case int64Type:
+		field.ParsedInt64Value = ParsedInt64Value(value, field.ParsedInt64Value)
+		field.RawValue = value
+	case secondType:
+		field.ParsedDuration = parseDurationValue(value, time.Second, field.ParsedDuration)
+		field.RawValue = value
+	case minuteType:
+		field.ParsedDuration = parseDurationValue(value, time.Minute, field.ParsedDuration)
+		field.RawValue = value
+	case hourType:
+		field.ParsedDuration = parseDurationValue(value, time.Hour, field.ParsedDuration)
+		field.RawValue = value
+	case dayType:
+		field.ParsedDuration = parseDurationValue(value, time.Hour*24, field.ParsedDuration)
+		field.RawValue = value
+	case urlType:
+		parsedURL, err := parseURLValue(value, field.ParsedURLValue)
+		if err != nil {
+			return fmt.Errorf("invalid URL for key %s: %v", key, err)
+		}
+		field.ParsedURLValue = parsedURL
+		field.RawValue = value
+	case secretFileType:
+		secretValue, err := readSecretFileValue(value)
+		if err != nil {
+			return fmt.Errorf("error reading secret file for key %s: %v", key, err)
+		}
+		if field.TargetKey != "" {
+			if targetField, ok := cp.options.options[field.TargetKey]; ok {
+				targetField.ParsedStringValue = secretValue
+				targetField.RawValue = secretValue
+			}
+		}
+		field.RawValue = value
+	case bytesType:
+		if value != "" {
+			field.ParsedBytesValue = []byte(value)
+			field.RawValue = value
+		}
+	}
+
+	return nil
+}
+
+func parseStringValue(value string, fallback string) string {
 	if value == "" {
 		return fallback
 	}
+	return value
+}
+
+func parseBoolValue(value string, fallback bool) (bool, error) {
+	if value == "" {
+		return fallback, nil
+	}
 
 	value = strings.ToLower(value)
 	if value == "1" || value == "yes" || value == "true" || value == "on" {
-		return true
+		return true, nil
+	}
+	if value == "0" || value == "no" || value == "false" || value == "off" {
+		return false, nil
 	}
 
-	return false
+	return false, fmt.Errorf("invalid boolean value: %q", value)
 }
 
-func parseInt(value string, fallback int) int {
+func parseIntValue(value string, fallback int) int {
 	if value == "" {
 		return fallback
 	}
@@ -324,14 +227,20 @@ func parseInt(value string, fallback int) int {
 	return v
 }
 
-func parseString(value string, fallback string) string {
+func ParsedInt64Value(value string, fallback int64) int64 {
 	if value == "" {
 		return fallback
 	}
-	return value
+
+	v, err := strconv.ParseInt(value, 10, 64)
+	if err != nil {
+		return fallback
+	}
+
+	return v
 }
 
-func parseStringList(value string, fallback []string) []string {
+func parseStringListValue(value string, fallback []string) []string {
 	if value == "" {
 		return fallback
 	}
@@ -351,16 +260,7 @@ func parseStringList(value string, fallback []string) []string {
 	return strList
 }
 
-func parseBytes(value string, fallback []byte) []byte {
+func parseDurationValue(value string, unit time.Duration, fallback time.Duration) time.Duration {
-	if value == "" {
-		return fallback
-	}
-
-	return []byte(value)
-}
-
-// parseInterval converts an integer "value" to [time.Duration] using "unit" as multiplier.
-func parseInterval(value string, unit time.Duration, fallback time.Duration) time.Duration {
 	if value == "" {
 		return fallback
 	}
@@ -373,16 +273,40 @@ func parseInterval(value string, unit time.Duration, fallback time.Duration) tim
 	return time.Duration(v) * unit
 }
 
-func readSecretFile(filename, fallback string) string {
+func parseURLValue(value string, fallback *url.URL) (*url.URL, error) {
+	if value == "" {
+		return fallback, nil
+	}
+
+	parsedURL, err := url.Parse(value)
+	if err != nil {
+		return fallback, err
+	}
+
+	return parsedURL, nil
+}
+
+func readSecretFileValue(filename string) (string, error) {
 	data, err := os.ReadFile(filename)
 	if err != nil {
-		return fallback
+		return "", err
 	}
 
 	value := string(bytes.TrimSpace(data))
 	if value == "" {
-		return fallback
+		return "", fmt.Errorf("secret file is empty")
 	}
 
-	return value
+	return value, nil
+}
+
+func parseFileContent(r io.Reader) (lines []string) {
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if !strings.HasPrefix(line, "#") && strings.Index(line, "=") > 0 {
+			lines = append(lines, line)
+		}
+	}
+	return lines
 }

internal/config/parser_test.go

@@ -4,163 +4,432 @@
 package config // import "miniflux.app/v2/internal/config"
 
 import (
+	"net/url"
+	"os"
 	"reflect"
 	"testing"
+	"time"
 )
 
-func TestParseBoolValue(t *testing.T) {
+func TestParseStringValue(t *testing.T) {
-	scenarios := map[string]bool{
+	// Test with non-empty value
-		"":        true,
+	result := parseStringValue("test", "fallback")
-		"1":       true,
+	if result != "test" {
-		"Yes":     true,
+		t.Errorf("Expected 'test', got '%s'", result)
-		"yes":     true,
-		"True":    true,
-		"true":    true,
-		"on":      true,
-		"false":   false,
-		"off":     false,
-		"invalid": false,
 	}
 
-	for input, expected := range scenarios {
+	// Test with empty value
-		result := parseBool(input, true)
+	result = parseStringValue("", "fallback")
-		if result != expected {
+	if result != "fallback" {
-			t.Errorf(`Unexpected result for %q, got %v instead of %v`, input, result, expected)
+		t.Errorf("Expected 'fallback', got '%s'", result)
+	}
+
+	// Test with empty value and empty fallback
+	result = parseStringValue("", "")
+	if result != "" {
+		t.Errorf("Expected empty string, got '%s'", result)
+	}
+}
+
+func TestParseBoolValue(t *testing.T) {
+	// Test with empty value - should return fallback
+	result, err := parseBoolValue("", true)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if result != true {
+		t.Errorf("Expected true, got %v", result)
+	}
+
+	// Test true values
+	trueValues := []string{"1", "yes", "true", "on", "YES", "TRUE", "ON"}
+	for _, value := range trueValues {
+		result, err := parseBoolValue(value, false)
+		if err != nil {
+			t.Errorf("Unexpected error for value '%s': %v", value, err)
+		}
+		if result != true {
+			t.Errorf("Expected true for '%s', got %v", value, result)
 		}
 	}
-}
 
-func TestParseStringValueWithUnsetVariable(t *testing.T) {
+	// Test false values
-	if parseString("", "defaultValue") != "defaultValue" {
+	falseValues := []string{"0", "no", "false", "off", "NO", "FALSE", "OFF"}
-		t.Errorf(`Unset variables should returns the default value`)
+	for _, value := range falseValues {
+		result, err := parseBoolValue(value, true)
+		if err != nil {
+			t.Errorf("Unexpected error for value '%s': %v", value, err)
+		}
+		if result != false {
+			t.Errorf("Expected false for '%s', got %v", value, result)
+		}
 	}
-}
 
-func TestParseStringValue(t *testing.T) {
+	// Test invalid value - should return error
-	if parseString("test", "defaultValue") != "test" {
+	_, err = parseBoolValue("invalid", false)
-		t.Errorf(`Defined variables should returns the specified value`)
+	if err == nil {
-	}
+		t.Error("Expected error for invalid boolean value")
-}
-
-func TestParseIntValueWithUnsetVariable(t *testing.T) {
-	if parseInt("", 42) != 42 {
-		t.Errorf(`Unset variables should returns the default value`)
-	}
-}
-
-func TestParseIntValueWithInvalidInput(t *testing.T) {
-	if parseInt("invalid integer", 42) != 42 {
-		t.Errorf(`Invalid integer should returns the default value`)
 	}
 }
 
 func TestParseIntValue(t *testing.T) {
-	if parseInt("2018", 42) != 2018 {
+	// Test with empty value - should return fallback
-		t.Errorf(`Defined variables should returns the specified value`)
+	result := parseIntValue("", 42)
+	if result != 42 {
+		t.Errorf("Expected 42, got %d", result)
+	}
+
+	// Test with valid integer
+	result = parseIntValue("123", 42)
+	if result != 123 {
+		t.Errorf("Expected 123, got %d", result)
+	}
+
+	// Test with invalid integer - should return fallback
+	result = parseIntValue("invalid", 42)
+	if result != 42 {
+		t.Errorf("Expected 42, got %d", result)
+	}
+
+	// Test with zero
+	result = parseIntValue("0", 42)
+	if result != 0 {
+		t.Errorf("Expected 0, got %d", result)
 	}
 }
 
-func TestParseListenAddr(t *testing.T) {
+func TestParsedInt64Value(t *testing.T) {
-	defaultExpected := []string{defaultListenAddr}
+	// Test with empty value - should return fallback
-
+	result := ParsedInt64Value("", 42)
-	tests := []struct {
+	if result != 42 {
-		name           string
+		t.Errorf("Expected 42, got %d", result)
-		listenAddr     string
-		port           string
-		expected       []string
-		lines          []string // Used for direct lines parsing instead of individual env vars
-		isLineOriented bool     // Flag to indicate if we use lines
-	}{
-		{
-			name:       "Single LISTEN_ADDR",
-			listenAddr: "127.0.0.1:8080",
-			expected:   []string{"127.0.0.1:8080"},
-		},
-		{
-			name:       "Multiple LISTEN_ADDR comma-separated",
-			listenAddr: "127.0.0.1:8080,:8081,/tmp/miniflux.sock",
-			expected:   []string{"127.0.0.1:8080", ":8081", "/tmp/miniflux.sock"},
-		},
-		{
-			name:       "Multiple LISTEN_ADDR with spaces around commas",
-			listenAddr: "127.0.0.1:8080 , :8081",
-			expected:   []string{"127.0.0.1:8080", ":8081"},
-		},
-		{
-			name:       "Empty LISTEN_ADDR",
-			listenAddr: "",
-			expected:   defaultExpected,
-		},
-		{
-			name:       "PORT overrides LISTEN_ADDR",
-			listenAddr: "127.0.0.1:8000",
-			port:       "8082",
-			expected:   []string{":8082"},
-		},
-		{
-			name:       "PORT overrides empty LISTEN_ADDR",
-			listenAddr: "",
-			port:       "8083",
-			expected:   []string{":8083"},
-		},
-		{
-			name:       "LISTEN_ADDR with empty segment (comma)",
-			listenAddr: "127.0.0.1:8080,,:8081",
-			expected:   []string{"127.0.0.1:8080", ":8081"},
-		},
-		{
-			name:           "PORT override with lines parsing",
-			isLineOriented: true,
-			lines:          []string{"LISTEN_ADDR=127.0.0.1:8000", "PORT=8082"},
-			expected:       []string{":8082"},
-		},
-		{
-			name:           "LISTEN_ADDR only with lines parsing (comma)",
-			isLineOriented: true,
-			lines:          []string{"LISTEN_ADDR=10.0.0.1:9090,10.0.0.2:9091"},
-			expected:       []string{"10.0.0.1:9090", "10.0.0.2:9091"},
-		},
-		{
-			name:           "Empty LISTEN_ADDR with lines parsing (default)",
-			isLineOriented: true,
-			lines:          []string{"LISTEN_ADDR="},
-			expected:       defaultExpected,
-		},
 	}
 
-	for _, tt := range tests {
+	// Test with valid int64
-		t.Run(tt.name, func(t *testing.T) {
+	result = ParsedInt64Value("9223372036854775807", 42)
-			parser := NewParser()
+	if result != 9223372036854775807 {
-			var err error
+		t.Errorf("Expected 9223372036854775807, got %d", result)
+	}
 
-			if tt.isLineOriented {
+	// Test with invalid int64 - should return fallback
-				err = parser.parseLines(tt.lines)
+	result = ParsedInt64Value("invalid", 42)
-			} else {
+	if result != 42 {
-				// Simulate os.Environ() behaviour for individual var testing
+		t.Errorf("Expected 42, got %d", result)
-				var envLines []string
+	}
-				if tt.listenAddr != "" {
+}
-					envLines = append(envLines, "LISTEN_ADDR="+tt.listenAddr)
+
-				}
+func TestParseStringListValue(t *testing.T) {
-				if tt.port != "" {
+	// Test with empty value - should return fallback
-					envLines = append(envLines, "PORT="+tt.port)
+	fallback := []string{"a", "b"}
-				}
+	result := parseStringListValue("", fallback)
-				// Add a dummy var if both are empty to avoid empty lines slice if not intended
+	if !reflect.DeepEqual(result, fallback) {
-				if tt.listenAddr == "" && tt.port == "" && tt.name == "Empty LISTEN_ADDR" {
+		t.Errorf("Expected %v, got %v", fallback, result)
-					// This case specifically tests empty LISTEN_ADDR resulting in default
+	}
-					// So, we pass LISTEN_ADDR=
+
-					envLines = append(envLines, "LISTEN_ADDR=")
+	// Test with single value
-				}
+	result = parseStringListValue("item1", nil)
-				err = parser.parseLines(envLines)
+	expected := []string{"item1"}
-			}
+	if !reflect.DeepEqual(result, expected) {
-
+		t.Errorf("Expected %v, got %v", expected, result)
-			if err != nil {
+	}
-				t.Fatalf("parseLines() error = %v", err)
+
-			}
+	// Test with multiple values
-
+	result = parseStringListValue("item1,item2,item3", nil)
-			opts := parser.opts
+	expected = []string{"item1", "item2", "item3"}
-			if !reflect.DeepEqual(opts.ListenAddr(), tt.expected) {
+	if !reflect.DeepEqual(result, expected) {
-				t.Errorf("ListenAddr() got = %v, want %v", opts.ListenAddr(), tt.expected)
+		t.Errorf("Expected %v, got %v", expected, result)
-			}
+	}
-		})
+
+	// Test with duplicates - should remove duplicates
+	result = parseStringListValue("item1,item2,item1", nil)
+	expected = []string{"item1", "item2"}
+	if !reflect.DeepEqual(result, expected) {
+		t.Errorf("Expected %v, got %v", expected, result)
+	}
+
+	// Test with spaces
+	result = parseStringListValue(" item1 , item2 , item3 ", nil)
+	expected = []string{"item1", "item2", "item3"}
+	if !reflect.DeepEqual(result, expected) {
+		t.Errorf("Expected %v, got %v", expected, result)
+	}
+}
+
+func TestParseDurationValue(t *testing.T) {
+	// Test with empty value - should return fallback
+	fallback := 5 * time.Second
+	result := parseDurationValue("", time.Second, fallback)
+	if result != fallback {
+		t.Errorf("Expected %v, got %v", fallback, result)
+	}
+
+	// Test with valid duration
+	result = parseDurationValue("30", time.Second, fallback)
+	expected := 30 * time.Second
+	if result != expected {
+		t.Errorf("Expected %v, got %v", expected, result)
+	}
+
+	// Test with minutes
+	result = parseDurationValue("5", time.Minute, fallback)
+	expected = 5 * time.Minute
+	if result != expected {
+		t.Errorf("Expected %v, got %v", expected, result)
+	}
+
+	// Test with invalid value - should return fallback
+	result = parseDurationValue("invalid", time.Second, fallback)
+	if result != fallback {
+		t.Errorf("Expected %v, got %v", fallback, result)
+	}
+}
+
+func TestParseURLValue(t *testing.T) {
+	// Test with empty value - should return fallback
+	fallbackURL, _ := url.Parse("https://fallback.com")
+	result, err := parseURLValue("", fallbackURL)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if result != fallbackURL {
+		t.Errorf("Expected %v, got %v", fallbackURL, result)
+	}
+
+	// Test with valid URL
+	result, err = parseURLValue("https://example.com", nil)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if result.String() != "https://example.com" {
+		t.Errorf("Expected https://example.com, got %s", result.String())
+	}
+
+	// Test with invalid URL - should return fallback and error
+	result, err = parseURLValue("://invalid", fallbackURL)
+	if err == nil {
+		t.Error("Expected error for invalid URL")
+	}
+	if result != fallbackURL {
+		t.Errorf("Expected fallback URL, got %v", result)
+	}
+}
+
+func TestConfigFileParsing(t *testing.T) {
+	fileContent := `
+		# This is a comment
+		LOG_FILE=miniflux.log
+		LOG_DATE_TIME=1
+		LOG_FORMAT=json
+		LISTEN_ADDR=:8080,:8443
+	`
+
+	// Write a temporary config file and parse it
+	tmpFile, err := os.CreateTemp("", "miniflux-*.txt")
+	if err != nil {
+		t.Fatalf("Failed to create temporary file: %v", err)
+	}
+
+	defer os.Remove(tmpFile.Name())
+	defer tmpFile.Close()
+
+	filename := tmpFile.Name()
+	if _, err := tmpFile.WriteString(fileContent); err != nil {
+		t.Fatalf("Failed to write to temporary file: %v", err)
+	}
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseFile(filename)
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogFile() != "miniflux.log" {
+		t.Fatalf("Unexpected log file, got %q", configOptions.LogFile())
+	}
+
+	if configOptions.LogDateTime() != true {
+		t.Fatalf("Unexpected log datetime, got %v", configOptions.LogDateTime())
+	}
+
+	if configOptions.LogFormat() != "json" {
+		t.Fatalf("Unexpected log format, got %q", configOptions.LogFormat())
+	}
+
+	if configOptions.LogLevel() != "info" {
+		t.Fatalf("Unexpected log level, got %q", configOptions.LogLevel())
+	}
+
+	if len(configOptions.ListenAddr()) != 2 || configOptions.ListenAddr()[0] != ":8080" || configOptions.ListenAddr()[1] != ":8443" {
+		t.Fatalf("Unexpected listen addresses, got %v", configOptions.ListenAddr())
+	}
+}
+
+func TestConfigFileParsingWithIncorrectKeyValuePair(t *testing.T) {
+	fileContent := `
+		LOG_FILE=miniflux.log
+		INVALID_LINE
+	`
+
+	// Write a temporary config file and parse it
+	tmpFile, err := os.CreateTemp("", "miniflux-*.txt")
+	if err != nil {
+		t.Fatalf("Failed to create temporary file: %v", err)
+	}
+
+	defer os.Remove(tmpFile.Name())
+	defer tmpFile.Close()
+
+	filename := tmpFile.Name()
+	if _, err := tmpFile.WriteString(fileContent); err != nil {
+		t.Fatalf("Failed to write to temporary file: %v", err)
+	}
+
+	configParser := NewConfigParser()
+	_, err = configParser.ParseFile(filename)
+	if err != nil {
+		t.Fatal("Invalid lines should be ignored, but got error:", err)
+	}
+}
+
+func TestParseAdminPasswordFileOption(t *testing.T) {
+	tmpFile, err := os.CreateTemp("", "password-*.txt")
+	if err != nil {
+		t.Fatalf("Failed to create temporary file: %v", err)
+	}
+	defer os.Remove(tmpFile.Name())
+	defer tmpFile.Close()
+
+	password := "supersecret"
+	if _, err := tmpFile.WriteString(password); err != nil {
+		t.Fatalf("Failed to write to temporary file: %v", err)
+	}
+
+	os.Clearenv()
+	os.Setenv("ADMIN_PASSWORD_FILE", tmpFile.Name())
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.AdminPassword() != password {
+		t.Fatalf("Unexpected admin password, got %q", configOptions.AdminPassword())
+	}
+}
+
+func TestParseAdminPasswordFileOptionWithEmptyFile(t *testing.T) {
+	tmpFile, err := os.CreateTemp("", "empty-password-*.txt")
+	if err != nil {
+		t.Fatalf("Failed to create temporary file: %v", err)
+	}
+	defer os.Remove(tmpFile.Name())
+	defer tmpFile.Close()
+
+	os.Clearenv()
+	os.Setenv("ADMIN_PASSWORD_FILE", tmpFile.Name())
+
+	configParser := NewConfigParser()
+	_, err = configParser.ParseEnvironmentVariables()
+	if err == nil {
+		t.Fatal("Expected error due to empty password file, but got none")
+	}
+}
+
+func TestParseLogFileOptionDefaultValue(t *testing.T) {
+	os.Clearenv()
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogFile() != "stderr" {
+		t.Fatalf("Unexpected default log file, got %q", configOptions.LogFile())
+	}
+}
+
+func TestParseLogFileOptionWithCustomFilename(t *testing.T) {
+	os.Clearenv()
+	os.Setenv("LOG_FILE", "miniflux.log")
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogFile() != "miniflux.log" {
+		t.Fatalf("Unexpected log file, got %q", configOptions.LogFile())
+	}
+}
+
+func TestParseLogFileOptionWithEmptyValue(t *testing.T) {
+	os.Clearenv()
+	os.Setenv("LOG_FILE", "")
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogFile() != "stderr" {
+		t.Fatalf("Unexpected log file, got %q", configOptions.LogFile())
+	}
+}
+
+func TestParseLogDateTimeOptionDefaultValue(t *testing.T) {
+	os.Clearenv()
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogDateTime() != false {
+		t.Fatalf("Unexpected default log datetime, got %v", configOptions.LogDateTime())
+	}
+}
+
+func TestParseLogDateTimeOptionWithCustomValue(t *testing.T) {
+	os.Clearenv()
+	os.Setenv("LOG_DATE_TIME", "true")
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogDateTime() != true {
+		t.Fatalf("Unexpected log datetime, got %v", configOptions.LogDateTime())
+	}
+}
+
+func TestParseLogDateTimeOptionWithEmptyValue(t *testing.T) {
+	os.Clearenv()
+	os.Setenv("LOG_DATE_TIME", "")
+
+	configParser := NewConfigParser()
+	configOptions, err := configParser.ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf("Unexpected parsing error: %v", err)
+	}
+
+	if configOptions.LogDateTime() != false {
+		t.Fatalf("Unexpected log datetime, got %v", configOptions.LogDateTime())
+	}
+}
+
+func TestParseLogDateTimeOptionWithIncorrectValue(t *testing.T) {
+	os.Clearenv()
+	os.Setenv("LOG_DATE_TIME", "invalid")
+
+	configParser := NewConfigParser()
+	if _, err := configParser.ParseEnvironmentVariables(); err == nil {
+		t.Fatal("Expected parsing error, got nil")
 	}
 }

internal/config/validators.go

@@ -0,0 +1,60 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package config // import "miniflux.app/v2/internal/config"
+
+import (
+	"fmt"
+	"slices"
+	"strconv"
+	"strings"
+)
+
+func validateChoices(rawValue string, choices []string) error {
+	if !slices.Contains(choices, rawValue) {
+		return fmt.Errorf("value must be one of: %v", strings.Join(choices, ", "))
+	}
+	return nil
+}
+
+func validateListChoices(inputValues, choices []string) error {
+	for _, value := range inputValues {
+		if !slices.Contains(choices, value) {
+			return fmt.Errorf("value must be one of: %v", strings.Join(choices, ", "))
+		}
+	}
+	return nil
+}
+
+func validateGreaterThan(rawValue string, min int) error {
+	intValue, err := strconv.Atoi(rawValue)
+	if err != nil {
+		return fmt.Errorf("value must be an integer")
+	}
+	if intValue > min {
+		return nil
+	}
+	return fmt.Errorf("value must be at least %d", min)
+}
+
+func validateGreaterOrEqualThan(rawValue string, min int) error {
+	intValue, err := strconv.Atoi(rawValue)
+	if err != nil {
+		return fmt.Errorf("value must be an integer")
+	}
+	if intValue >= min {
+		return nil
+	}
+	return fmt.Errorf("value must be greater or equal than %d", min)
+}
+
+func validateRange(rawValue string, min, max int) error {
+	intValue, err := strconv.Atoi(rawValue)
+	if err != nil {
+		return fmt.Errorf("value must be an integer")
+	}
+	if intValue < min || intValue > max {
+		return fmt.Errorf("value must be between %d and %d", min, max)
+	}
+	return nil
+}

internal/config/validators_test.go

@@ -0,0 +1,372 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package config // import "miniflux.app/v2/internal/config"
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestValidateChoices(t *testing.T) {
+	tests := []struct {
+		name        string
+		rawValue    string
+		choices     []string
+		expectError bool
+	}{
+		{
+			name:        "valid choice",
+			rawValue:    "option1",
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "valid choice from middle",
+			rawValue:    "option2",
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "valid choice from end",
+			rawValue:    "option3",
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "invalid choice",
+			rawValue:    "invalid",
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: true,
+		},
+		{
+			name:        "empty value with non-empty choices",
+			rawValue:    "",
+			choices:     []string{"option1", "option2"},
+			expectError: true,
+		},
+		{
+			name:        "case sensitive - different case",
+			rawValue:    "OPTION1",
+			choices:     []string{"option1", "option2"},
+			expectError: true,
+		},
+		{
+			name:        "single choice valid",
+			rawValue:    "only",
+			choices:     []string{"only"},
+			expectError: false,
+		},
+		{
+			name:        "empty choices list",
+			rawValue:    "anything",
+			choices:     []string{},
+			expectError: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := validateChoices(tt.rawValue, tt.choices)
+			if tt.expectError {
+				if err == nil {
+					t.Errorf("expected error but got none")
+				} else {
+					// Verify error message format
+					expectedPrefix := "value must be one of:"
+					if !strings.Contains(err.Error(), expectedPrefix) {
+						t.Errorf("error message should contain '%s', got: %s", expectedPrefix, err.Error())
+					}
+				}
+			} else {
+				if err != nil {
+					t.Errorf("expected no error but got: %v", err)
+				}
+			}
+		})
+	}
+}
+
+func TestValidateListChoices(t *testing.T) {
+	tests := []struct {
+		name        string
+		inputValues []string
+		choices     []string
+		expectError bool
+	}{
+		{
+			name:        "all valid choices",
+			inputValues: []string{"option1", "option2"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "single valid choice",
+			inputValues: []string{"option1"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "empty input list",
+			inputValues: []string{},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "all choices from available list",
+			inputValues: []string{"option1", "option2", "option3"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "duplicate valid choices",
+			inputValues: []string{"option1", "option1", "option2"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: false,
+		},
+		{
+			name:        "one invalid choice",
+			inputValues: []string{"option1", "invalid"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: true,
+		},
+		{
+			name:        "all invalid choices",
+			inputValues: []string{"invalid1", "invalid2"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: true,
+		},
+		{
+			name:        "case sensitive - different case",
+			inputValues: []string{"OPTION1"},
+			choices:     []string{"option1", "option2"},
+			expectError: true,
+		},
+		{
+			name:        "empty string in input",
+			inputValues: []string{""},
+			choices:     []string{"option1", "option2"},
+			expectError: true,
+		},
+		{
+			name:        "empty choices list with non-empty input",
+			inputValues: []string{"anything"},
+			choices:     []string{},
+			expectError: true,
+		},
+		{
+			name:        "mixed valid and invalid choices",
+			inputValues: []string{"option1", "invalid", "option2"},
+			choices:     []string{"option1", "option2", "option3"},
+			expectError: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := validateListChoices(tt.inputValues, tt.choices)
+			if tt.expectError {
+				if err == nil {
+					t.Errorf("expected error but got none")
+				} else {
+					// Verify error message format
+					expectedPrefix := "value must be one of:"
+					if !strings.Contains(err.Error(), expectedPrefix) {
+						t.Errorf("error message should contain '%s', got: %s", expectedPrefix, err.Error())
+					}
+				}
+			} else {
+				if err != nil {
+					t.Errorf("expected no error but got: %v", err)
+				}
+			}
+		})
+	}
+}
+
+func TestValidateGreaterThan(t *testing.T) {
+	if err := validateGreaterThan("10", 5); err != nil {
+		t.Errorf("expected no error, got: %v", err)
+	}
+
+	if err := validateGreaterThan("5", 5); err == nil {
+		t.Errorf("expected error, got none")
+	}
+
+	if err := validateGreaterThan("abc", 5); err == nil {
+		t.Errorf("expected error for non-integer input, got none")
+	}
+
+	if err := validateGreaterThan("-1", 0); err == nil {
+		t.Errorf("expected error for value below minimum, got none")
+	}
+}
+
+func TestValidateGreaterOrEqualThan(t *testing.T) {
+	if err := validateGreaterOrEqualThan("10", 5); err != nil {
+		t.Errorf("expected no error, got: %v", err)
+	}
+
+	if err := validateGreaterOrEqualThan("5", 5); err != nil {
+		t.Errorf("expected no error for equal value, got: %v", err)
+	}
+
+	if err := validateGreaterOrEqualThan("abc", 5); err == nil {
+		t.Errorf("expected error for non-integer input, got none")
+	}
+
+	if err := validateGreaterOrEqualThan("-1", 0); err == nil {
+		t.Errorf("expected error for value below minimum, got none")
+	}
+}
+
+func TestValidateRange(t *testing.T) {
+	tests := []struct {
+		name        string
+		rawValue    string
+		min         int
+		max         int
+		expectError bool
+		errorMsg    string
+	}{
+		{
+			name:        "valid integer within range",
+			rawValue:    "5",
+			min:         1,
+			max:         10,
+			expectError: false,
+		},
+		{
+			name:        "valid integer at minimum",
+			rawValue:    "1",
+			min:         1,
+			max:         10,
+			expectError: false,
+		},
+		{
+			name:        "valid integer at maximum",
+			rawValue:    "10",
+			min:         1,
+			max:         10,
+			expectError: false,
+		},
+		{
+			name:        "valid zero in range",
+			rawValue:    "0",
+			min:         -5,
+			max:         5,
+			expectError: false,
+		},
+		{
+			name:        "valid negative in range",
+			rawValue:    "-3",
+			min:         -5,
+			max:         5,
+			expectError: false,
+		},
+		{
+			name:        "integer below minimum",
+			rawValue:    "0",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be between 1 and 10",
+		},
+		{
+			name:        "integer above maximum",
+			rawValue:    "11",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be between 1 and 10",
+		},
+		{
+			name:        "integer far below minimum",
+			rawValue:    "-100",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be between 1 and 10",
+		},
+		{
+			name:        "integer far above maximum",
+			rawValue:    "100",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be between 1 and 10",
+		},
+		{
+			name:        "non-integer string",
+			rawValue:    "abc",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be an integer",
+		},
+		{
+			name:        "empty string",
+			rawValue:    "",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be an integer",
+		},
+		{
+			name:        "float string",
+			rawValue:    "5.5",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be an integer",
+		},
+		{
+			name:        "string with spaces",
+			rawValue:    " 5 ",
+			min:         1,
+			max:         10,
+			expectError: true,
+			errorMsg:    "value must be an integer",
+		},
+		{
+			name:        "single value range",
+			rawValue:    "5",
+			min:         5,
+			max:         5,
+			expectError: false,
+		},
+		{
+			name:        "single value range - below",
+			rawValue:    "4",
+			min:         5,
+			max:         5,
+			expectError: true,
+			errorMsg:    "value must be between 5 and 5",
+		},
+		{
+			name:        "single value range - above",
+			rawValue:    "6",
+			min:         5,
+			max:         5,
+			expectError: true,
+			errorMsg:    "value must be between 5 and 5",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := validateRange(tt.rawValue, tt.min, tt.max)
+			if tt.expectError {
+				if err == nil {
+					t.Errorf("expected error but got none")
+				} else if tt.errorMsg != "" && err.Error() != tt.errorMsg {
+					t.Errorf("expected error message '%s', got '%s'", tt.errorMsg, err.Error())
+				}
+			} else {
+				if err != nil {
+					t.Errorf("expected no error but got: %v", err)
+				}
+			}
+		})
+	}
+}

internal/http/server/httpd.go

@@ -60,7 +60,7 @@ func StartWebServer(store *storage.Storage, pool *worker.Pool) []*http.Server {
 				slog.Error("ACME HTTP challenge server failed", slog.Any("error", err))
 			}
 		}()
-		config.Opts.HTTPS = true
+		config.Opts.SetHTTPSValue(true)
 		httpServers = append(httpServers, challengeServer)
 	}
 
@@ -95,7 +95,7 @@ func StartWebServer(store *storage.Storage, pool *worker.Pool) []*http.Server {
 		case certFile != "" && keyFile != "":
 			server.Addr = listenAddr
 			startTLSServer(server, certFile, keyFile)
-			config.Opts.HTTPS = true
+			config.Opts.SetHTTPSValue(true)
 		default:
 			server.Addr = listenAddr
 			startHTTPServer(server)
@@ -148,7 +148,7 @@ func startUnixSocketServer(server *http.Server, socketFile string) {
 				slog.String("key_file", keyFile),
 			)
 			// Ensure HTTPS is marked as true if any listener uses TLS
-			config.Opts.HTTPS = true
+			config.Opts.SetHTTPSValue(true)
 			if err := server.ServeTLS(listener, certFile, keyFile); err != http.ErrServerClosed {
 				printErrorAndExit("TLS Unix socket server failed to start on %s: %v", socketFile, err)
 			}

internal/http/server/middleware.go

@@ -20,7 +20,7 @@ func middleware(next http.Handler) http.Handler {
 		ctx = context.WithValue(ctx, request.ClientIPContextKey, clientIP)
 
 		if r.Header.Get("X-Forwarded-Proto") == "https" {
-			config.Opts.HTTPS = true
+			config.Opts.SetHTTPSValue(true)
 		}
 
 		t1 := time.Now()
@@ -36,7 +36,7 @@ func middleware(next http.Handler) http.Handler {
 			)
 		}()
 
-		if config.Opts.HTTPS && config.Opts.HasHSTS() {
+		if config.Opts.HTTPS() && config.Opts.HasHSTS() {
 			w.Header().Set("Strict-Transport-Security", "max-age=31536000")
 		}
 

internal/mediaproxy/media_proxy_test.go

@@ -19,7 +19,7 @@ func TestProxyFilterWithHttpDefault(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -43,7 +43,7 @@ func TestProxyFilterWithHttpsDefault(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_RESOURCE_TYPES", "image")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -66,7 +66,7 @@ func TestProxyFilterWithHttpNever(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_MODE", "none")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -89,7 +89,7 @@ func TestProxyFilterWithHttpsNever(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_MODE", "none")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -114,7 +114,7 @@ func TestProxyFilterWithHttpAlways(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -139,7 +139,7 @@ func TestProxyFilterWithHttpsAlways(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -164,7 +164,7 @@ func TestAbsoluteProxyFilterWithHttpsAlways(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -188,7 +188,7 @@ func TestAbsoluteProxyFilterWithCustomPortAndSubfolderInBaseURL(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -226,7 +226,7 @@ func TestAbsoluteProxyFilterWithHttpsAlwaysAndAudioTag(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -251,7 +251,7 @@ func TestProxyFilterWithHttpsAlwaysAndCustomProxyServer(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_CUSTOM_URL", "https://proxy-example/proxy")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -276,7 +276,7 @@ func TestProxyFilterWithHttpsAlwaysAndIncorrectCustomProxyServer(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_CUSTOM_URL", "http://:8080example.com")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err == nil {
 		t.Fatalf(`Incorrect proxy URL silently accepted (MEDIA_PROXY_CUSTOM_URL=%q): %q`, os.Getenv("MEDIA_PROXY_CUSTOM_URL"), config.Opts.MediaCustomProxyURL())
@@ -290,7 +290,7 @@ func TestAbsoluteProxyFilterWithHttpsAlwaysAndCustomProxyServer(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_CUSTOM_URL", "https://proxy-example/proxy")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -313,46 +313,8 @@ func TestProxyFilterWithHttpInvalid(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_MODE", "invalid")
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
-	var err error
+	if _, err := config.NewConfigParser().ParseEnvironmentVariables(); err == nil {
-	parser := config.NewParser()
+		t.Fatalf(`Parsing should have failed (MEDIA_PROXY_MODE=%q): %q`, os.Getenv("MEDIA_PROXY_MODE"), config.Opts.MediaProxyMode())
-	config.Opts, err = parser.ParseEnvironmentVariables()
-	if err != nil {
-		t.Fatalf(`Parsing failure: %v`, err)
-	}
-
-	r := mux.NewRouter()
-	r.HandleFunc("/proxy/{encodedDigest}/{encodedURL}", func(w http.ResponseWriter, r *http.Request) {}).Name("proxy")
-
-	input := `<p><img src="http://website/folder/image.png" alt="Test"/></p>`
-	output := RewriteDocumentWithRelativeProxyURL(r, input)
-	expected := `<p><img src="/proxy/okK5PsdNY8F082UMQEAbLPeUFfbe2WnNfInNmR9T4WA=/aHR0cDovL3dlYnNpdGUvZm9sZGVyL2ltYWdlLnBuZw==" alt="Test"/></p>`
-
-	if expected != output {
-		t.Errorf(`Not expected output: got %q instead of %q`, output, expected)
-	}
-}
-
-func TestProxyFilterWithHttpsInvalid(t *testing.T) {
-	os.Clearenv()
-	os.Setenv("MEDIA_PROXY_MODE", "invalid")
-	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
-
-	var err error
-	parser := config.NewParser()
-	config.Opts, err = parser.ParseEnvironmentVariables()
-	if err != nil {
-		t.Fatalf(`Parsing failure: %v`, err)
-	}
-
-	r := mux.NewRouter()
-	r.HandleFunc("/proxy/{encodedDigest}/{encodedURL}", func(w http.ResponseWriter, r *http.Request) {}).Name("proxy")
-
-	input := `<p><img src="https://website/folder/image.png" alt="Test"/></p>`
-	output := RewriteDocumentWithRelativeProxyURL(r, input)
-	expected := `<p><img src="https://website/folder/image.png" alt="Test"/></p>`
-
-	if expected != output {
-		t.Errorf(`Not expected output: got %q instead of %q`, output, expected)
 	}
 }
 
@@ -363,7 +325,7 @@ func TestProxyFilterWithSrcset(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -388,7 +350,7 @@ func TestProxyFilterWithEmptySrcset(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -413,7 +375,7 @@ func TestProxyFilterWithPictureSource(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -433,12 +395,12 @@ func TestProxyFilterWithPictureSource(t *testing.T) {
 
 func TestProxyFilterOnlyNonHTTPWithPictureSource(t *testing.T) {
 	os.Clearenv()
-	os.Setenv("MEDIA_PROXY_MODE", "https")
+	os.Setenv("MEDIA_PROXY_MODE", "http-only")
 	os.Setenv("MEDIA_PROXY_RESOURCE_TYPES", "image")
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -462,7 +424,7 @@ func TestProxyWithImageDataURL(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_RESOURCE_TYPES", "image")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -486,7 +448,7 @@ func TestProxyWithImageSourceDataURL(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_RESOURCE_TYPES", "image")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -511,7 +473,7 @@ func TestProxyFilterWithVideo(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -536,7 +498,7 @@ func TestProxyFilterVideoPoster(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -561,7 +523,7 @@ func TestProxyFilterVideoPosterOnce(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)

internal/model/enclosure_test.go

@@ -290,7 +290,7 @@ func TestEnclosure_ProxifyEnclosureURL(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test-private-key")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Config parsing failure: %v`, err)
@@ -420,7 +420,7 @@ func TestEnclosureList_ProxifyEnclosureURL(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test-private-key")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Config parsing failure: %v`, err)
@@ -535,7 +535,7 @@ func TestEnclosure_ProxifyEnclosureURL_EdgeCases(t *testing.T) {
 	os.Setenv("MEDIA_PROXY_PRIVATE_KEY", "test-private-key")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Config parsing failure: %v`, err)

internal/model/feed_test.go

@@ -80,7 +80,7 @@ func TestFeedScheduleNextCheckRoundRobinDefault(t *testing.T) {
 	os.Clearenv()
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -102,7 +102,7 @@ func TestFeedScheduleNextCheckRoundRobinWithRefreshDelayAboveMinInterval(t *test
 	os.Clearenv()
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -125,7 +125,7 @@ func TestFeedScheduleNextCheckRoundRobinWithRefreshDelayBelowMinInterval(t *test
 	os.Clearenv()
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -148,7 +148,7 @@ func TestFeedScheduleNextCheckRoundRobinWithRefreshDelayAboveMaxInterval(t *test
 	os.Clearenv()
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -174,7 +174,7 @@ func TestFeedScheduleNextCheckRoundRobinMinInterval(t *testing.T) {
 	os.Setenv("SCHEDULER_ROUND_ROBIN_MIN_INTERVAL", strconv.Itoa(minInterval))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -201,7 +201,7 @@ func TestFeedScheduleNextCheckEntryFrequencyMaxInterval(t *testing.T) {
 	os.Setenv("SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL", strconv.Itoa(minInterval))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -230,7 +230,7 @@ func TestFeedScheduleNextCheckEntryFrequencyMaxIntervalZeroWeeklyCount(t *testin
 	os.Setenv("SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL", strconv.Itoa(minInterval))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -259,7 +259,7 @@ func TestFeedScheduleNextCheckEntryFrequencyMinInterval(t *testing.T) {
 	os.Setenv("SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL", strconv.Itoa(minInterval))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -286,7 +286,7 @@ func TestFeedScheduleNextCheckEntryFrequencyFactor(t *testing.T) {
 	os.Setenv("SCHEDULER_ENTRY_FREQUENCY_FACTOR", strconv.Itoa(factor))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -315,7 +315,7 @@ func TestFeedScheduleNextCheckEntryFrequencySmallNewTTL(t *testing.T) {
 	os.Setenv("SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL", strconv.Itoa(minInterval))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
@@ -351,7 +351,7 @@ func TestFeedScheduleNextCheckEntryFrequencyLargeNewTTL(t *testing.T) {
 	os.Setenv("SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL", strconv.Itoa(minInterval))
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)

internal/reader/filter/filter_test.go

@@ -414,7 +414,7 @@ func TestKeeplistRulesBehavior(t *testing.T) {
 // Tests for isBlockedGlobally function
 func TestIsBlockedGlobally(t *testing.T) {
 	var err error
-	config.Opts, err = config.NewParser().ParseEnvironmentVariables()
+	config.Opts, err = config.NewConfigParser().ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
 	}
@@ -429,7 +429,7 @@ func TestIsBlockedGlobally(t *testing.T) {
 	os.Setenv("FILTER_ENTRY_MAX_AGE_DAYS", "30")
 	defer os.Clearenv()
 
-	config.Opts, err = config.NewParser().ParseEnvironmentVariables()
+	config.Opts, err = config.NewConfigParser().ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
 	}

internal/reader/processor/youtube.go

@@ -31,11 +31,11 @@ func getVideoIDFromYouTubeURL(websiteURL string) string {
 }
 
 func shouldFetchYouTubeWatchTimeForSingleEntry(entry *model.Entry) bool {
-	return config.Opts.FetchYouTubeWatchTime() && config.Opts.YouTubeApiKey() == "" && isYouTubeVideoURL(entry.URL)
+	return config.Opts.FetchYouTubeWatchTime() && config.Opts.YouTubeAPIKey() == "" && isYouTubeVideoURL(entry.URL)
 }
 
 func shouldFetchYouTubeWatchTimeInBulk() bool {
-	return config.Opts.FetchYouTubeWatchTime() && config.Opts.YouTubeApiKey() != ""
+	return config.Opts.FetchYouTubeWatchTime() && config.Opts.YouTubeAPIKey() != ""
 }
 
 func fetchYouTubeWatchTimeForSingleEntry(websiteURL string) (int, error) {
@@ -82,7 +82,7 @@ func fetchYouTubeWatchTimeFromApiInBulk(videoIDs []string) (map[string]time.Dura
 
 	apiQuery := url.Values{}
 	apiQuery.Set("id", strings.Join(videoIDs, ","))
-	apiQuery.Set("key", config.Opts.YouTubeApiKey())
+	apiQuery.Set("key", config.Opts.YouTubeAPIKey())
 	apiQuery.Set("part", "contentDetails")
 
 	apiURL := url.URL{

internal/reader/rewrite/content_rewrite_test.go

@@ -67,7 +67,7 @@ func TestRewriteWithNoMatchingRule(t *testing.T) {
 }
 
 func TestRewriteYoutubeVideoLink(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	controlEntry := &model.Entry{
 		URL:     "https://www.youtube.com/watch?v=1234",
@@ -87,7 +87,7 @@ func TestRewriteYoutubeVideoLink(t *testing.T) {
 }
 
 func TestRewriteYoutubeShortLink(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	controlEntry := &model.Entry{
 		URL:     "https://www.youtube.com/shorts/1LUWKWZkPjo",
@@ -107,7 +107,7 @@ func TestRewriteYoutubeShortLink(t *testing.T) {
 }
 
 func TestRewriteIncorrectYoutubeLink(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	controlEntry := &model.Entry{
 		URL:     "https://www.youtube.com/some-page",
@@ -131,7 +131,7 @@ func TestRewriteYoutubeLinkAndCustomEmbedURL(t *testing.T) {
 	os.Setenv("YOUTUBE_EMBED_URL_OVERRIDE", "https://invidious.custom/embed/")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 
 	if err != nil {
@@ -156,7 +156,7 @@ func TestRewriteYoutubeLinkAndCustomEmbedURL(t *testing.T) {
 }
 
 func TestRewriteYoutubeVideoLinkUsingInvidious(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 	controlEntry := &model.Entry{
 		URL:     "https://www.youtube.com/watch?v=1234",
 		Title:   `A title`,
@@ -176,7 +176,7 @@ func TestRewriteYoutubeVideoLinkUsingInvidious(t *testing.T) {
 }
 
 func TestRewriteYoutubeShortLinkUsingInvidious(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 	controlEntry := &model.Entry{
 		URL:     "https://www.youtube.com/shorts/1LUWKWZkPjo",
 		Title:   `A title`,
@@ -196,7 +196,7 @@ func TestRewriteYoutubeShortLinkUsingInvidious(t *testing.T) {
 }
 
 func TestAddYoutubeVideoFromId(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	scenarios := map[string]string{
 		// Test with single YouTube ID
@@ -239,7 +239,7 @@ func TestAddYoutubeVideoFromIdWithCustomEmbedURL(t *testing.T) {
 	os.Setenv("YOUTUBE_EMBED_URL_OVERRIDE", "https://invidious.custom/embed/")
 
 	var err error
-	parser := config.NewParser()
+	parser := config.NewConfigParser()
 	config.Opts, err = parser.ParseEnvironmentVariables()
 
 	if err != nil {

internal/reader/sanitizer/sanitizer_test.go

@@ -392,7 +392,7 @@ func TestInvalidNestedTag(t *testing.T) {
 }
 
 func TestInvalidIFrame(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	input := `<iframe src="http://example.org/"></iframe>`
 	expected := ``
@@ -404,7 +404,7 @@ func TestInvalidIFrame(t *testing.T) {
 }
 
 func TestSameDomainIFrame(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	input := `<iframe src="http://example.com/test"></iframe>`
 	expected := ``
@@ -416,7 +416,7 @@ func TestSameDomainIFrame(t *testing.T) {
 }
 
 func TestInvidiousIFrame(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	input := `<iframe src="https://yewtu.be/watch?v=video_id"></iframe>`
 	expected := `<iframe src="https://yewtu.be/watch?v=video_id" sandbox="allow-scripts allow-same-origin allow-popups allow-popups-to-escape-sandbox" loading="lazy"></iframe>`
@@ -432,7 +432,7 @@ func TestCustomYoutubeEmbedURL(t *testing.T) {
 
 	defer os.Clearenv()
 	var err error
-	if config.Opts, err = config.NewParser().ParseEnvironmentVariables(); err != nil {
+	if config.Opts, err = config.NewConfigParser().ParseEnvironmentVariables(); err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
 	}
 
@@ -446,7 +446,7 @@ func TestCustomYoutubeEmbedURL(t *testing.T) {
 }
 
 func TestIFrameWithChildElements(t *testing.T) {
-	config.Opts = config.NewOptions()
+	config.Opts = config.NewConfigOptions()
 
 	input := `<iframe src="https://www.youtube.com/"><p>test</p></iframe>`
 	expected := `<iframe src="https://www.youtube.com/" sandbox="allow-scripts allow-same-origin allow-popups allow-popups-to-escape-sandbox" loading="lazy"></iframe>`
@@ -850,7 +850,7 @@ func TestReplaceYoutubeURLWithCustomURL(t *testing.T) {
 	os.Setenv("YOUTUBE_EMBED_URL_OVERRIDE", "https://invidious.custom/embed/")
 
 	var err error
-	config.Opts, err = config.NewParser().ParseEnvironmentVariables()
+	config.Opts, err = config.NewConfigParser().ParseEnvironmentVariables()
 	if err != nil {
 		t.Fatalf(`Parsing failure: %v`, err)
 	}

internal/template/functions.go

@@ -41,7 +41,7 @@ func (f *funcMap) Map() template.FuncMap {
 		"baseURL":          config.Opts.BaseURL,
 		"rootURL":          config.Opts.RootURL,
 		"disableLocalAuth": config.Opts.DisableLocalAuth,
-		"oidcProviderName": config.Opts.OIDCProviderName,
+		"oidcProviderName": config.Opts.OAuth2OIDCProviderName,
 		"hasOAuth2Provider": func(provider string) bool {
 			return config.Opts.OAuth2Provider() == provider
 		},

internal/ui/about.go

@@ -33,7 +33,7 @@ func (h *handler) showAboutPage(w http.ResponseWriter, r *http.Request) {
 	view.Set("user", user)
 	view.Set("countUnread", h.store.CountUnreadEntries(user.ID))
 	view.Set("countErrorFeeds", h.store.CountUserFeedsWithErrors(user.ID))
-	view.Set("globalConfigOptions", config.Opts.SortedOptions(true))
+	view.Set("globalConfigOptions", config.Opts.ConfigMap(true))
 	view.Set("postgres_version", h.store.DatabaseVersion())
 	view.Set("go_version", runtime.Version())
 

internal/ui/login_check.go

@@ -89,7 +89,7 @@ func (h *handler) checkLogin(w http.ResponseWriter, r *http.Request) {
 	http.SetCookie(w, cookie.New(
 		cookie.CookieUserSessionID,
 		sessionToken,
-		config.Opts.HTTPS,
+		config.Opts.HTTPS(),
 		config.Opts.BasePath(),
 	))
 

internal/ui/logout.go

@@ -32,7 +32,7 @@ func (h *handler) logout(w http.ResponseWriter, r *http.Request) {
 
 	http.SetCookie(w, cookie.Expired(
 		cookie.CookieUserSessionID,
-		config.Opts.HTTPS,
+		config.Opts.HTTPS(),
 		config.Opts.BasePath(),
 	))
 

internal/ui/middleware.go

@@ -93,7 +93,7 @@ func (m *middleware) handleAppSession(next http.Handler) http.Handler {
 				}
 			}
 
-			http.SetCookie(w, cookie.New(cookie.CookieAppSessionID, session.ID, config.Opts.HTTPS, config.Opts.BasePath()))
+			http.SetCookie(w, cookie.New(cookie.CookieAppSessionID, session.ID, config.Opts.HTTPS(), config.Opts.BasePath()))
 		}
 
 		if r.Method == http.MethodPost {
@@ -261,7 +261,7 @@ func (m *middleware) handleAuthProxy(next http.Handler) http.Handler {
 		http.SetCookie(w, cookie.New(
 			cookie.CookieUserSessionID,
 			sessionToken,
-			config.Opts.HTTPS,
+			config.Opts.HTTPS(),
 			config.Opts.BasePath(),
 		))
 

internal/ui/oauth2.go

@@ -16,6 +16,6 @@ func getOAuth2Manager(ctx context.Context) *oauth2.Manager {
 		config.Opts.OAuth2ClientID(),
 		config.Opts.OAuth2ClientSecret(),
 		config.Opts.OAuth2RedirectURL(),
-		config.Opts.OIDCDiscoveryEndpoint(),
+		config.Opts.OAuth2OIDCDiscoveryEndpoint(),
 	)
 }

internal/ui/oauth2_callback.go

@@ -145,7 +145,7 @@ func (h *handler) oauth2Callback(w http.ResponseWriter, r *http.Request) {
 	http.SetCookie(w, cookie.New(
 		cookie.CookieUserSessionID,
 		sessionToken,
-		config.Opts.HTTPS,
+		config.Opts.HTTPS(),
 		config.Opts.BasePath(),
 	))
 

internal/ui/webauthn.go

@@ -331,7 +331,7 @@ func (h *handler) finishLogin(w http.ResponseWriter, r *http.Request) {
 	http.SetCookie(w, cookie.New(
 		cookie.CookieUserSessionID,
 		sessionToken,
-		config.Opts.HTTPS,
+		config.Opts.HTTPS(),
 		config.Opts.BasePath(),
 	))
 

miniflux.1

@@ -329,7 +329,7 @@ Default is 300 seconds\&.
 .B HTTPS
 Forces cookies to use secure flag and send HSTS header\&.
 .br
-Default is empty\&.
+Default is disabled\&.
 .TP
 .B INVIDIOUS_INSTANCE
 Set a custom invidious instance to use\&.
@@ -466,7 +466,7 @@ Default is empty\&.
 .B OAUTH2_OIDC_PROVIDER_NAME
 Name to display for the OIDC provider\&.
 .br
-Default is OpenID Connect\&.
+Default is "OpenID Connect"\&.
 .TP
 .B OAUTH2_PROVIDER
 Possible values are "google" or "oidc"\&.
@@ -537,7 +537,7 @@ Default is 1\&.
 .B SCHEDULER_ENTRY_FREQUENCY_MAX_INTERVAL
 Maximum interval in minutes for the entry frequency scheduler\&.
 .br
-Default is 24 hours\&.
+Default is 1440 minutes (24 hours)\&.
 .TP
 .B SCHEDULER_ENTRY_FREQUENCY_MIN_INTERVAL
 Minimum interval in minutes for the entry frequency scheduler\&.