Simplify feed entries filtering

- Rename processor package to filter
- Remove boilerplate code

reader/processor/processor.go

@@ -1,71 +0,0 @@
-// 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 processor // import "miniflux.app/reader/processor"
-
-import (
-	"miniflux.app/logger"
-	"miniflux.app/model"
-	"miniflux.app/reader/rewrite"
-	"miniflux.app/reader/sanitizer"
-	"miniflux.app/reader/scraper"
-	"miniflux.app/storage"
-)
-
-// FeedProcessor handles the processing of feed contents.
-type FeedProcessor struct {
-	userID       int64
-	store        *storage.Storage
-	feed         *model.Feed
-	scraperRules string
-	rewriteRules string
-	crawler      bool
-	userAgent    string
-}
-
-// WithCrawler enables the crawler.
-func (f *FeedProcessor) WithCrawler(value bool) {
-	f.crawler = value
-}
-
-// WithScraperRules adds scraper rules to the processing.
-func (f *FeedProcessor) WithScraperRules(rules string) {
-	f.scraperRules = rules
-}
-
-// WithUserAgent sets the User-Agent header for fetching article content.
-func (f *FeedProcessor) WithUserAgent(userAgent string) {
-	f.userAgent = userAgent
-}
-
-// WithRewriteRules adds rewrite rules to the processing.
-func (f *FeedProcessor) WithRewriteRules(rules string) {
-	f.rewriteRules = rules
-}
-
-// Process applies rewrite and scraper rules.
-func (f *FeedProcessor) Process() {
-	for _, entry := range f.feed.Entries {
-		if f.crawler {
-			if f.store.EntryURLExists(f.userID, entry.URL) {
-				logger.Debug(`[FeedProcessor] Do not crawl existing entry URL: "%s"`, entry.URL)
-			} else {
-				content, err := scraper.Fetch(entry.URL, f.scraperRules, f.userAgent)
-				if err != nil {
-					logger.Error("[FeedProcessor] %v", err)
-				} else {
-					entry.Content = content
-				}
-			}
-		}
-
-		entry.Content = rewrite.Rewriter(entry.URL, entry.Content, f.rewriteRules)
-		entry.Content = sanitizer.Sanitize(entry.URL, entry.Content)
-	}
-}
-
-// NewFeedProcessor returns a new FeedProcessor.
-func NewFeedProcessor(userID int64, store *storage.Storage, feed *model.Feed) *FeedProcessor {
-	return &FeedProcessor{userID: userID, store: store, feed: feed, crawler: false}
-}