First commit

reader/feed/handler.go

@@ -0,0 +1,152 @@
+// Copyright 2017 Frédéric Guillot. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+package feed
+
+import (
+	"fmt"
+	"github.com/miniflux/miniflux2/errors"
+	"github.com/miniflux/miniflux2/helper"
+	"github.com/miniflux/miniflux2/model"
+	"github.com/miniflux/miniflux2/reader/http"
+	"github.com/miniflux/miniflux2/reader/icon"
+	"github.com/miniflux/miniflux2/storage"
+	"log"
+	"time"
+)
+
+var (
+	errRequestFailed = "Unable to execute request: %v"
+	errServerFailure = "Unable to fetch feed (statusCode=%d)."
+	errDuplicate     = "This feed already exists (%s)."
+	errNotFound      = "Feed %d not found"
+)
+
+// Handler contains all the logic to create and refresh feeds.
+type Handler struct {
+	store *storage.Storage
+}
+
+// CreateFeed fetch, parse and store a new feed.
+func (h *Handler) CreateFeed(userID, categoryID int64, url string) (*model.Feed, error) {
+	defer helper.ExecutionTime(time.Now(), fmt.Sprintf("[Handler:CreateFeed] feedUrl=%s", url))
+
+	client := http.NewHttpClient(url)
+	response, err := client.Get()
+	if err != nil {
+		return nil, errors.NewLocalizedError(errRequestFailed, err)
+	}
+
+	if response.HasServerFailure() {
+		return nil, errors.NewLocalizedError(errServerFailure, response.StatusCode)
+	}
+
+	if h.store.FeedURLExists(userID, response.EffectiveURL) {
+		return nil, errors.NewLocalizedError(errDuplicate, response.EffectiveURL)
+	}
+
+	subscription, err := parseFeed(response.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	subscription.Category = &model.Category{ID: categoryID}
+	subscription.EtagHeader = response.ETag
+	subscription.LastModifiedHeader = response.LastModified
+	subscription.FeedURL = response.EffectiveURL
+	subscription.UserID = userID
+
+	err = h.store.CreateFeed(subscription)
+	if err != nil {
+		return nil, err
+	}
+
+	log.Println("[Handler:CreateFeed] Feed saved with ID:", subscription.ID)
+
+	icon, err := icon.FindIcon(subscription.SiteURL)
+	if err != nil {
+		log.Println(err)
+	} else if icon == nil {
+		log.Printf("No icon found for feedID=%d\n", subscription.ID)
+	} else {
+		h.store.CreateFeedIcon(subscription, icon)
+	}
+
+	return subscription, nil
+}
+
+// RefreshFeed fetch and update a feed if necessary.
+func (h *Handler) RefreshFeed(userID, feedID int64) error {
+	defer helper.ExecutionTime(time.Now(), fmt.Sprintf("[Handler:RefreshFeed] feedID=%d", feedID))
+
+	originalFeed, err := h.store.GetFeedById(userID, feedID)
+	if err != nil {
+		return err
+	}
+
+	if originalFeed == nil {
+		return errors.NewLocalizedError(errNotFound, feedID)
+	}
+
+	client := http.NewHttpClientWithCacheHeaders(originalFeed.FeedURL, originalFeed.EtagHeader, originalFeed.LastModifiedHeader)
+	response, err := client.Get()
+	if err != nil {
+		customErr := errors.NewLocalizedError(errRequestFailed, err)
+		originalFeed.ParsingErrorCount++
+		originalFeed.ParsingErrorMsg = customErr.Error()
+		h.store.UpdateFeed(originalFeed)
+		return customErr
+	}
+
+	originalFeed.CheckedAt = time.Now()
+
+	if response.HasServerFailure() {
+		err := errors.NewLocalizedError(errServerFailure, response.StatusCode)
+		originalFeed.ParsingErrorCount++
+		originalFeed.ParsingErrorMsg = err.Error()
+		h.store.UpdateFeed(originalFeed)
+		return err
+	}
+
+	if response.IsModified(originalFeed.EtagHeader, originalFeed.LastModifiedHeader) {
+		log.Printf("[Handler:RefreshFeed] Feed #%d has been modified\n", feedID)
+
+		subscription, err := parseFeed(response.Body)
+		if err != nil {
+			originalFeed.ParsingErrorCount++
+			originalFeed.ParsingErrorMsg = err.Error()
+			h.store.UpdateFeed(originalFeed)
+			return err
+		}
+
+		originalFeed.EtagHeader = response.ETag
+		originalFeed.LastModifiedHeader = response.LastModified
+
+		if err := h.store.UpdateEntries(originalFeed.UserID, originalFeed.ID, subscription.Entries); err != nil {
+			return err
+		}
+
+		if !h.store.HasIcon(originalFeed.ID) {
+			log.Println("[Handler:RefreshFeed] Looking for feed icon")
+			icon, err := icon.FindIcon(originalFeed.SiteURL)
+			if err != nil {
+				log.Println("[Handler:RefreshFeed]", err)
+			} else {
+				h.store.CreateFeedIcon(originalFeed, icon)
+			}
+		}
+	} else {
+		log.Printf("[Handler:RefreshFeed] Feed #%d not modified\n", feedID)
+	}
+
+	originalFeed.ParsingErrorCount = 0
+	originalFeed.ParsingErrorMsg = ""
+
+	return h.store.UpdateFeed(originalFeed)
+}
+
+// NewFeedHandler returns a feed handler.
+func NewFeedHandler(store *storage.Storage) *Handler {
+	return &Handler{store: store}
+}