Added blog page, article page and added latest articles to start page.

blog/blog.go

@@ -0,0 +1,189 @@
+package blog
+
+import (
+	"github.com/Kugelschieber/marvinblum.de/tpl"
+	emvi "github.com/emvi/api-go"
+	"github.com/emvi/logbuch"
+	"github.com/gorilla/mux"
+	"html/template"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+)
+
+const (
+	blogCacheTime     = time.Hour
+	maxLatestArticles = 3
+)
+
+var (
+	blog Blog
+)
+
+type Blog struct {
+	client       *emvi.Client
+	articles     map[string]emvi.Article // id -> article
+	articlesYear map[int][]emvi.Article  // year -> articles
+	nextUpdate   time.Time
+}
+
+func InitBlog() {
+	logbuch.Info("Initializing blog")
+	blog.client = emvi.NewClient(os.Getenv("MB_EMVI_CLIENT_ID"),
+		os.Getenv("MB_EMVI_CLIENT_SECRET"),
+		os.Getenv("MB_EMVI_ORGA"),
+		nil)
+	blog.nextUpdate = time.Now().Add(blogCacheTime)
+	blog.loadArticles()
+}
+
+func (blog *Blog) loadArticles() {
+	logbuch.Info("Refreshing blog articles...")
+	articles, offset, count := make(map[string]emvi.Article), 0, 1
+	var err error
+
+	for count > 0 {
+		var results []emvi.Article
+		results, _, err = blog.client.FindArticles("", &emvi.ArticleFilter{
+			BaseSearch:    emvi.BaseSearch{Offset: offset},
+			Tags:          "blog",
+			SortPublished: emvi.SortDescending,
+		})
+
+		if err != nil {
+			logbuch.Error("Error loading blog articles", logbuch.Fields{"err": err})
+			break
+		}
+
+		offset += len(results)
+		count = len(results)
+
+		for _, article := range results {
+			articles[article.Id] = article
+		}
+	}
+
+	if err == nil {
+		for k, v := range articles {
+			v.LatestArticleContent = blog.loadArticle(v)
+			articles[k] = v
+		}
+
+		blog.setArticles(articles)
+	}
+
+	blog.nextUpdate = time.Now().Add(blogCacheTime)
+	logbuch.Info("Done", logbuch.Fields{"count": len(articles)})
+}
+
+func (blog *Blog) loadArticle(article emvi.Article) *emvi.ArticleContent {
+	_, content, _, err := blog.client.GetArticle(article.Id, article.LatestArticleContent.LanguageId, 0)
+
+	if err != nil {
+		logbuch.Error("Error loading article", logbuch.Fields{"err": err, "id": article.Id})
+		return nil
+	}
+
+	logbuch.Debug("Article loaded", logbuch.Fields{"id": article.Id})
+	return content
+}
+
+func (blog *Blog) setArticles(articles map[string]emvi.Article) {
+	blog.articles = articles
+	blog.articlesYear = make(map[int][]emvi.Article)
+
+	for _, article := range articles {
+		if blog.articlesYear[article.Published.Year()] == nil {
+			blog.articlesYear[article.Published.Year()] = make([]emvi.Article, 0)
+		}
+
+		blog.articlesYear[article.Published.Year()] = append(blog.articlesYear[article.Published.Year()], article)
+	}
+}
+
+func (blog *Blog) getArticle(id string) emvi.Article {
+	blog.refreshIfRequired()
+	return blog.articles[id]
+}
+
+func (blog *Blog) getArticles() map[int][]emvi.Article {
+	blog.refreshIfRequired()
+	return blog.articlesYear
+}
+
+func (blog *Blog) getLatestArticles() []emvi.Article {
+	blog.refreshIfRequired()
+	articles := make([]emvi.Article, 0, 3)
+	i := 0
+
+	for _, v := range blog.articles {
+		articles = append(articles, v)
+		i++
+
+		if i > maxLatestArticles {
+			break
+		}
+	}
+
+	return articles
+}
+
+func (blog *Blog) refreshIfRequired() {
+	if blog.nextUpdate.Before(time.Now()) {
+		blog.loadArticles()
+	}
+}
+
+func GetLatestArticles() []emvi.Article {
+	return blog.getLatestArticles()
+}
+
+func ServeBlogPage() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		data := struct {
+			Articles map[int][]emvi.Article
+		}{
+			blog.getArticles(),
+		}
+
+		if err := tpl.Get().ExecuteTemplate(w, "blog.html", data); err != nil {
+			logbuch.Error("Error executing blog template", logbuch.Fields{"err": err})
+			w.WriteHeader(http.StatusInternalServerError)
+		}
+	}
+}
+
+func ServeBlogArticle() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		vars := mux.Vars(r)
+		slug := strings.Split(vars["slug"], "-")
+
+		if len(slug) == 0 {
+			http.Redirect(w, r, "/notfound", http.StatusFound)
+			return
+		}
+
+		article := blog.getArticle(slug[len(slug)-1])
+
+		if len(article.Id) == 0 {
+			http.Redirect(w, r, "/notfound", http.StatusFound)
+			return
+		}
+
+		data := struct {
+			Title     string
+			Content   template.HTML
+			Published string
+		}{
+			article.LatestArticleContent.Title,
+			template.HTML(article.LatestArticleContent.Content),
+			article.Published.Format("2. January 2006"),
+		}
+
+		if err := tpl.Get().ExecuteTemplate(w, "article.html", data); err != nil {
+			logbuch.Error("Error executing blog article template", logbuch.Fields{"err": err})
+			w.WriteHeader(http.StatusInternalServerError)
+		}
+	}
+}