Changed articles and rss to channels

cmd/data/articles.go

@@ -1,7 +1,6 @@
 package data
 
 import (
-	"sync"
 	"time"
 
 	"github.com/google/uuid"
@@ -12,30 +11,66 @@ type Article struct {
 	Created time.Time
 	Desc    string
 	Content string
+	Tags    []string
 	UUID    uuid.UUID
 }
 
 type ArticleList struct {
-	List []Article
-	sync.Mutex
+	addCh  chan *Article
+	delCh  chan uuid.UUID
+	retCh  chan *Article
+	listCh chan []Article
+	list   []*Article
 }
 
-func (l *ArticleList) Add(a Article) {
-	l.Lock()
-	l.List = append(l.List, a)
-	l.Unlock()
-}
-
-func (l *ArticleList) Release(uuid uuid.UUID) (Article, bool) {
-	l.Lock()
-	for i, article := range l.List {
-		if article.UUID == uuid {
-			foo := l.List[i]
-			l.List = append(l.List[:i], l.List[i+1:]...)
-			l.Unlock()
-			return foo, true
+func (l *ArticleList) start() {
+	for {
+		select {
+		case article := <-l.addCh:
+			l.list = append(l.list, article)
+		case uuid := <-l.delCh:
+			for i, article := range l.list {
+				if article.UUID == uuid {
+					l.list = append(l.list[:i], l.list[i+1:]...)
+					l.retCh <- article
+				}
+			}
+		case l.listCh <- func() []Article {
+			var list []Article
+			for _, article := range l.list {
+				list = append(list, *article)
+			}
+			return list
+		}():
 		}
 	}
-	l.Unlock()
-	return Article{}, false
+}
+
+func NewArticleList() *ArticleList {
+	list := &ArticleList{
+		addCh:  make(chan *Article),
+		delCh:  make(chan uuid.UUID),
+		retCh:  make(chan *Article),
+		listCh: make(chan []Article),
+		list:   []*Article{},
+	}
+	go list.start()
+	return list
+}
+
+func (l *ArticleList) Add(a *Article) {
+	l.addCh <- a
+}
+
+func (l *ArticleList) Release(uuid uuid.UUID) (*Article, bool) {
+	l.delCh <- uuid
+	article := <-l.retCh
+	if article == nil {
+		return nil, false
+	}
+	return article, true
+}
+
+func (l *ArticleList) List() []Article {
+	return <-l.listCh
 }

cmd/data/rss.go

@@ -4,40 +4,66 @@ import (
 	"encoding/gob"
 	"fmt"
 	"os"
-	"sync"
 
 	"github.com/gorilla/feeds"
 )
 
 type Feed struct {
-	feeds.Feed
-	sync.Mutex
+	addCh  chan *feeds.Item
+	openCh chan feeds.Feed
+	saveCh chan feeds.Feed
+	showCh chan feeds.Feed
+	feed   feeds.Feed
+}
+
+func (f *Feed) start() {
+	for {
+		select {
+		case item := <-f.addCh:
+			f.feed.Items = append(f.feed.Items, item)
+		case f.saveCh <- f.feed:
+		case tmpFeed := <-f.openCh:
+			f.feed = tmpFeed
+		case f.showCh <- f.feed:
+		}
+	}
 }
 
 func NewFeed(title, link, desc string) *Feed {
-	return &Feed{
-		Feed: feeds.Feed{
+	feed := &Feed{
+		addCh:  make(chan *feeds.Item),
+		openCh: make(chan feeds.Feed),
+		saveCh: make(chan feeds.Feed),
+		showCh: make(chan feeds.Feed),
+		feed: feeds.Feed{
 			Title:       title,
 			Link:        &feeds.Link{Href: link},
 			Description: desc,
 		},
 	}
+	go feed.start()
+	return feed
 }
 
 func OpenFeed(filename string) (*Feed, error) {
+	feed := new(Feed)
+	go feed.start()
+
 	file, err := os.Open(filename)
 	if err != nil {
 		return nil, fmt.Errorf("error opening file %v: %v", filename, err)
 	}
 	defer file.Close()
 
-	feed := new(Feed)
 	decoder := gob.NewDecoder(file)
-	err = decoder.Decode(&feed.Feed)
+	tmpFeed := new(feeds.Feed)
+	err = decoder.Decode(tmpFeed)
 	if err != nil {
 		return nil, fmt.Errorf("error decoding file %v: %v", filename, err)
 	}
 
+	feed.openCh <- *tmpFeed
+
 	return feed, nil
 }
 
@@ -49,9 +75,8 @@ func (f *Feed) Save(filename string) error {
 	defer file.Close()
 
 	encoder := gob.NewEncoder(file)
-	f.Lock()
-	err = encoder.Encode(f.Feed)
-	f.Unlock()
+	feed := <-f.saveCh
+	err = encoder.Encode(feed)
 	if err != nil {
 		return fmt.Errorf("error encoding file %v: %v", filename, err)
 	}
@@ -60,7 +85,9 @@ func (f *Feed) Save(filename string) error {
 }
 
 func (f *Feed) Add(i *feeds.Item) {
-	f.Lock()
-	f.Items = append(f.Items, i)
-	f.Unlock()
+	f.addCh <- i
+}
+
+func (f *Feed) Show() feeds.Feed {
+	return <-f.showCh
 }

cmd/ui/articles.go

@@ -25,7 +25,7 @@ func WriteArticle() http.HandlerFunc {
 
 func FinishArticle(l *data.ArticleList) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		article := data.Article{}
+		article := new(data.Article)
 		var err error
 
 		article.Title, err = data.ConvertToPlain(r.PostFormValue("editor-title"))
@@ -73,7 +73,7 @@ func ReviewArticle(l *data.ArticleList) http.HandlerFunc {
 			return
 		}
 
-		for _, article := range l.List {
+		for _, article := range l.List() {
 			if article.UUID == uuid {
 				template.Must(template.ParseFiles("web/templates/to-be-published.html")).ExecuteTemplate(w, "page-content", article)
 				return

cmd/ui/rss.go

@@ -8,8 +8,9 @@ import (
 	"streifling.com/jason/cpolis/cmd/data"
 )
 
-func ShowRSS(feed *data.Feed) http.HandlerFunc {
+func ShowRSS(f *data.Feed) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
+		feed := f.Show()
 		rss, err := feed.ToRss()
 		if err != nil {
 			log.Println(err)

main.go

@@ -31,7 +31,7 @@ func main() {
 			"Freiheit, Gleichheit, Brüderlichkeit, Toleranz und Humanität")
 	}
 
-	articleList := new(data.ArticleList)
+	articleList := data.NewArticleList()
 
 	mux := http.NewServeMux()
 	mux.Handle("/web/static/", http.StripPrefix("/web/static/", http.FileServer(http.Dir("web/static/"))))