use function instead of method to get posts

Author: samdfonseca

Makefile

@@ -25,3 +25,8 @@ check:
 build: GOFLAGS += -i -o dingo
 build:
 	$(GO) build -v $(GOFLAGS) main.go
+
+.PHONY: run
+run: GOFLAGS += -race
+run:
+	$(GO) run -v $(GOFLAGS) main.go

app/handler/post.go

@@ -12,7 +12,7 @@ import (
 
 func registerPostHandlers(app *golf.Application, routes map[string]map[string]interface{}) {
 	adminChain := golf.NewChain(JWTAuthMiddleware)
-	app.Get("/api/posts", APIPostsHandler)
+	app.Get("/api/posts", APIPostsHandler(0, 10))
 	routes["GET"]["posts_url"] = "/api/posts"
 
 	app.Get("/api/posts/:post_id", APIPostHandler)
@@ -91,34 +91,52 @@ func APIPostSlugHandler(ctx *golf.Context) {
 	ctx.JSON(NewAPISuccessResponse(post))
 }
 
-// APIPostsHandler gets every page, ordered by publication date.
-func APIPostsHandler(ctx *golf.Context) {
-	posts := new(model.Posts)
-	switch limitPublixhed := ctx.Param("published") {
-	case "true":
-		pubPosts := posts.GetAllPostList(false, true, "published_at DESC")
-		posts.AppendPosts(pubPosts)
-	case "false":
-		unpubPosts := posts.GetAllPostList(false, false, "created_at DESC")
-		posts.AppendPosts(unpubPosts)
-	default:
-		pubPosts := posts.GetAllPostList(false, true, "published_at DESC")
-		posts.AppendPosts(pubPosts)
-		unpubPosts := posts.GetAllPostList(false, false, "created_at DESC")
-		posts.AppendPosts(unpubPosts)
-	}
-	ctx.JSON(NewAPISuccessResponse(posts))
-	limitPublished, convErr := strconv.ParseBool(limitPublished)
-	if convErr != nil {
-		handleErr(ctx, 500, convErr)
-		return
-	}
-	err := posts.GetAllPostList(false, true, "published_at DESC")
-	if err != nil {
-		handleErr(ctx, 404, err)
-		return
+// APIPostsHandler gets an array of posts of length <= limit, starting at offset.
+// To paginate through posts, increment offset by limit until the length of the
+// post array in the response is less than limit.
+func APIPostsHandler(offset, limit int) golf.HandlerFunc {
+	// offset, limit args are default values
+	return func(ctx *golf.Context) {
+		var posts []*model.Post
+		var err error
+		err = ctx.Request.ParseForm()
+		if err != nil {
+			ctx.SendStatus(http.StatusInternalServerError)
+			ctx.JSON(APIResponseBodyJSON{Status: NewErrorStatusJSON(err.Error())})
+			return
+		}
+		if q, _ := ctx.Query("offset"); q != "" {
+			offset, err = strconv.Atoi(q)
+		}
+		if err != nil {
+			ctx.SendStatus(http.StatusBadRequest)
+			ctx.JSON(APIResponseBodyJSON{Status: NewErrorStatusJSON(err.Error())})
+			return
+		}
+		if q, _ := ctx.Query("limit"); q != "" {
+			limit, err = strconv.Atoi(q)
+		}
+		if err != nil {
+			ctx.SendStatus(http.StatusBadRequest)
+			ctx.JSON(APIResponseBodyJSON{Status: NewErrorStatusJSON(err.Error())})
+			return
+		}
+		published, _ := ctx.Query("published")
+		switch published {
+		case "true":
+			posts, err = model.GetPublishedPosts(offset, limit)
+		case "false":
+			posts, err = model.GetUnpublishedPosts(offset, limit)
+		default:
+			posts, err = model.GetAllPosts(offset, limit)
+		}
+		if err != nil {
+			ctx.SendStatus(http.StatusInternalServerError)
+			ctx.JSON(APIResponseBodyJSON{Status: NewErrorStatusJSON(err.Error())})
+			return
+		}
+		ctx.JSON(NewAPISuccessResponse(posts))
 	}
-	ctx.JSON(NewAPISuccessResponse(posts))
 }
 
 // APIPostCommentsHandler gets the comments on the given post.

app/model/comment.go

@@ -168,7 +168,6 @@ func buildCommentTree(p *Comment, c *Comment, level int) {
 func DeleteComment(id int64) error {
 	writeDB, err := db.Begin()
 	if err != nil {
-		writeDB
 		writeDB.Rollback()
 		return err
 	}

app/model/post.go

@@ -19,6 +19,7 @@ const stmtGetPostBySlug = `SELECT * FROM posts WHERE slug = ?`
 const stmtGetPostsByTag = `SELECT * FROM posts WHERE %s id IN ( SELECT post_id FROM posts_tags WHERE tag_id = ? ) ORDER BY published_at DESC LIMIT ? OFFSET ?`
 const stmtGetAllPostsByTag = `SELECT * FROM posts WHERE id IN ( SELECT post_id FROM posts_tags WHERE tag_id = ?) ORDER BY published_at DESC `
 const stmtGetPostsCountByTag = "SELECT count(*) FROM posts, posts_tags WHERE posts_tags.post_id = posts.id AND posts.published AND posts_tags.tag_id = ?"
+const stmtGetPostsOffsetLimit = `SELECT * FROM posts WHERE published = ? LIMIT ?, ?`
 const stmtInsertPostTag = `INSERT INTO posts_tags (id, post_id, tag_id) VALUES (?, ?, ?)`
 const stmtDeletePostTagsByPostId = `DELETE FROM posts_tags WHERE post_id = ?`
 const stmtNumberOfPosts = "SELECT count(*) FROM posts WHERE %s"
@@ -422,3 +423,28 @@ func getSafeOrderByStmt(orderBy string) string {
 	}
 	return "published_at DESC"
 }
+
+func GetPublishedPosts(offset, limit int) (Posts, error) {
+	var posts Posts
+	err := meddler.QueryAll(db, &posts, stmtGetPostsOffsetLimit, 1, offset, limit)
+	return posts, err
+}
+
+func GetUnpublishedPosts(offset, limit int) (Posts, error) {
+	var posts Posts
+	err := meddler.QueryAll(db, &posts, stmtGetPostsOffsetLimit, 0,  offset, limit)
+	return posts, err
+}
+
+func GetAllPosts(offset, limit int) ([]*Post, error) {
+	pubPosts, err := GetPublishedPosts(offset, limit)
+	if err != nil {
+		return nil, err
+	}
+	unpubPosts, err := GetUnpublishedPosts(offset, limit)
+	if err != nil {
+		return nil, err
+	}
+	posts := append(pubPosts, unpubPosts...)
+	return posts, nil
+}

app/model/post_test.go

@@ -155,17 +155,9 @@ func TestPost(t *testing.T) {
 				So(err, ShouldBeNil)
 			})
 
-			Convey("Get all published posts list", func() {
+			Convey("Get all posts list", func() {
 				posts := new(Posts)
-				err := posts.GetAllPostList(false, true, "created_at")
-
-				So(posts, ShouldHaveLength, 1)
-				So(err, ShouldBeNil)
-			})
-
-			Convey("Get all unpublished posts list", func() {
-				posts := new(Posts)
-				err := posts.GetAllPostList(false, true, "created_at")
+				err := posts.GetAllPostList(false, false, "created_at")
 
 				So(posts, ShouldHaveLength, 1)
 				So(err, ShouldBeNil)