Rename api package to http

1 files changed, 274 insertions, 0 deletions

diff --git a/srv/src/http/posts.go b/srv/src/http/posts.go
new file mode 100644
index 0000000..fd583ea
--- /dev/null
+++ b/srv/src/http/posts.go
@@ -0,0 +1,274 @@
+package http
+
+import (
+	"errors"
+	"fmt"
+	"html/template"
+	"net/http"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/gomarkdown/markdown"
+	"github.com/gomarkdown/markdown/html"
+	"github.com/gomarkdown/markdown/parser"
+	"github.com/mediocregopher/blog.mediocregopher.com/srv/http/apiutil"
+	"github.com/mediocregopher/blog.mediocregopher.com/srv/post"
+)
+
+type postTplPayload struct {
+	post.StoredPost
+	SeriesPrevious, SeriesNext *post.StoredPost
+	Body                       template.HTML
+}
+
+func (a *api) postToPostTplPayload(storedPost post.StoredPost) (postTplPayload, error) {
+	parserExt := parser.CommonExtensions | parser.AutoHeadingIDs
+	parser := parser.NewWithExtensions(parserExt)
+
+	htmlFlags := html.CommonFlags | html.HrefTargetBlank
+	htmlRenderer := html.NewRenderer(html.RendererOptions{Flags: htmlFlags})
+
+	renderedBody := markdown.ToHTML([]byte(storedPost.Body), parser, htmlRenderer)
+
+	tplPayload := postTplPayload{
+		StoredPost: storedPost,
+		Body:       template.HTML(renderedBody),
+	}
+
+	if series := storedPost.Series; series != "" {
+
+		seriesPosts, err := a.params.PostStore.GetBySeries(series)
+		if err != nil {
+			return postTplPayload{}, fmt.Errorf(
+				"fetching posts for series %q: %w", series, err,
+			)
+		}
+
+		var foundThis bool
+
+		for i := range seriesPosts {
+
+			seriesPost := seriesPosts[i]
+
+			if seriesPost.ID == storedPost.ID {
+				foundThis = true
+				continue
+			}
+
+			if !foundThis {
+				tplPayload.SeriesPrevious = &seriesPost
+				continue
+			}
+
+			tplPayload.SeriesNext = &seriesPost
+			break
+		}
+	}
+
+	return tplPayload, nil
+}
+
+func (a *api) renderPostHandler() http.Handler {
+
+	tpl := a.mustParseBasedTpl("post.html")
+	renderIndexHandler := a.renderPostsIndexHandler()
+
+	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+
+		id := strings.TrimSuffix(filepath.Base(r.URL.Path), ".html")
+
+		if id == "/" {
+			renderIndexHandler.ServeHTTP(rw, r)
+			return
+		}
+
+		storedPost, err := a.params.PostStore.GetByID(id)
+
+		if errors.Is(err, post.ErrPostNotFound) {
+			http.Error(rw, "Post not found", 404)
+			return
+		} else if err != nil {
+			apiutil.InternalServerError(
+				rw, r, fmt.Errorf("fetching post with id %q: %w", id, err),
+			)
+			return
+		}
+
+		tplPayload, err := a.postToPostTplPayload(storedPost)
+
+		if err != nil {
+			apiutil.InternalServerError(
+				rw, r, fmt.Errorf(
+					"generating template payload for post with id %q: %w",
+					id, err,
+				),
+			)
+			return
+		}
+
+		executeTemplate(rw, r, tpl, tplPayload)
+	})
+}
+
+func (a *api) renderPostsIndexHandler() http.Handler {
+
+	tpl := a.mustParseBasedTpl("posts.html")
+	const pageCount = 20
+
+	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+
+		page, err := apiutil.StrToInt(r.FormValue("p"), 0)
+		if err != nil {
+			apiutil.BadRequest(
+				rw, r, fmt.Errorf("invalid page number: %w", err),
+			)
+			return
+		}
+
+		posts, hasMore, err := a.params.PostStore.WithOrderDesc().Get(page, pageCount)
+		if err != nil {
+			apiutil.InternalServerError(
+				rw, r, fmt.Errorf("fetching page %d of posts: %w", page, err),
+			)
+			return
+		}
+
+		tplPayload := struct {
+			Posts              []post.StoredPost
+			PrevPage, NextPage int
+		}{
+			Posts:    posts,
+			PrevPage: -1,
+			NextPage: -1,
+		}
+
+		if page > 0 {
+			tplPayload.PrevPage = page - 1
+		}
+
+		if hasMore {
+			tplPayload.NextPage = page + 1
+		}
+
+		executeTemplate(rw, r, tpl, tplPayload)
+	})
+}
+
+func (a *api) editPostHandler() http.Handler {
+
+	tpl := a.mustParseBasedTpl("edit-post.html")
+
+	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+
+		id := filepath.Base(r.URL.Path)
+
+		var storedPost post.StoredPost
+
+		if id != "/" {
+
+			var err error
+			storedPost, err = a.params.PostStore.GetByID(id)
+
+			if errors.Is(err, post.ErrPostNotFound) {
+				http.Error(rw, "Post not found", 404)
+				return
+			} else if err != nil {
+				apiutil.InternalServerError(
+					rw, r, fmt.Errorf("fetching post with id %q: %w", id, err),
+				)
+				return
+			}
+		}
+
+		executeTemplate(rw, r, tpl, storedPost)
+	})
+}
+
+func postFromPostReq(r *http.Request) post.Post {
+
+	p := post.Post{
+		ID:          r.PostFormValue("id"),
+		Title:       r.PostFormValue("title"),
+		Description: r.PostFormValue("description"),
+		Tags:        strings.Fields(r.PostFormValue("tags")),
+		Series:      r.PostFormValue("series"),
+	}
+
+	p.Body = strings.TrimSpace(r.PostFormValue("body"))
+	// textareas encode newlines as CRLF for historical reasons
+	p.Body = strings.ReplaceAll(p.Body, "\r\n", "\n")
+
+	return p
+}
+
+func (a *api) postPostHandler() http.Handler {
+
+	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+
+		p := postFromPostReq(r)
+
+		if err := a.params.PostStore.Set(p, time.Now()); err != nil {
+			apiutil.InternalServerError(
+				rw, r, fmt.Errorf("storing post with id %q: %w", p.ID, err),
+			)
+			return
+		}
+
+		redirectPath := fmt.Sprintf("posts/%s?method=edit", p.ID)
+
+		a.executeRedirectTpl(rw, r, redirectPath)
+	})
+}
+
+func (a *api) deletePostHandler() http.Handler {
+
+	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+
+		id := filepath.Base(r.URL.Path)
+
+		if id == "/" {
+			apiutil.BadRequest(rw, r, errors.New("id is required"))
+			return
+		}
+
+		err := a.params.PostStore.Delete(id)
+
+		if errors.Is(err, post.ErrPostNotFound) {
+			http.Error(rw, "Post not found", 404)
+			return
+		} else if err != nil {
+			apiutil.InternalServerError(
+				rw, r, fmt.Errorf("deleting post with id %q: %w", id, err),
+			)
+			return
+		}
+
+		a.executeRedirectTpl(rw, r, "posts/")
+
+	})
+}
+
+func (a *api) previewPostHandler() http.Handler {
+
+	tpl := a.mustParseBasedTpl("post.html")
+
+	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+
+		storedPost := post.StoredPost{
+			Post:        postFromPostReq(r),
+			PublishedAt: time.Now(),
+		}
+
+		tplPayload, err := a.postToPostTplPayload(storedPost)
+
+		if err != nil {
+			apiutil.InternalServerError(
+				rw, r, fmt.Errorf("generating template payload: %w", err),
+			)
+			return
+		}
+
+		executeTemplate(rw, r, tpl, tplPayload)
+	})
+}