progress on embedr

bskyweb/cmd/embedr/handlers.go

@@ -0,0 +1,223 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+
+	appbsky "github.com/bluesky-social/indigo/api/bsky"
+	"github.com/bluesky-social/indigo/atproto/syntax"
+
+	"github.com/labstack/echo/v4"
+)
+
+var ErrPostNotFound = errors.New("post not found")
+var ErrPostNotPublic = errors.New("post is not publicly accessible")
+
+func (srv *Server) getBlueskyPost(ctx context.Context, did syntax.DID, rkey syntax.RecordKey) (*appbsky.FeedDefs_PostView, error) {
+
+	// requires two fetches: first fetch profile
+	pv, err := appbsky.ActorGetProfile(ctx, srv.xrpcc, did.String())
+	if err != nil {
+		log.Warnf("failed to fetch profile for: %s\t%v", did, err)
+		// TODO: detect 404, specifically?
+		return nil, ErrPostNotFound
+	}
+	for _, label := range pv.Labels {
+		if label.Src == pv.Did && label.Val == "!no-unauthenticated" {
+			return nil, ErrPostNotPublic
+		}
+	}
+
+	// then fetch the post thread (with extra context)
+	uri := fmt.Sprintf("at://%s/app.bsky.feed.post/%s", did, rkey)
+	tpv, err := appbsky.FeedGetPostThread(ctx, srv.xrpcc, 1, 0, uri)
+	if err != nil {
+		log.Warnf("failed to fetch post: %s\t%v", uri, err)
+		// TODO: detect 404, specifically?
+		return nil, ErrPostNotFound
+	}
+
+	if tpv.Thread.FeedDefs_BlockedPost != nil {
+		return nil, ErrPostNotPublic
+	} else if tpv.Thread.FeedDefs_ThreadViewPost.Post == nil {
+		return nil, ErrPostNotFound
+	}
+	return tpv.Thread.FeedDefs_ThreadViewPost.Post, nil
+}
+
+func (srv *Server) WebHome(c echo.Context) error {
+	return c.Render(http.StatusOK, "home.html", nil)
+}
+
+type OEmbedResponse struct {
+	Type         string `json:"type"`
+	Version      string `json:"version"`
+	AuthorName   string `json:"author_name,omitempty"`
+	AuthorURL    string `json:"author_url,omitempty"`
+	ProviderName string `json:"provider_url,omitempty"`
+	CacheAge     int    `json:"cache_age,omitempty"`
+	Width        int    `json:"width,omitempty"`
+	Height       *int   `json:"height,omitempty"`
+	HTML         string `json:"html,omitempty"`
+}
+
+func (srv *Server) parseBlueskyURL(ctx context.Context, raw string) (*syntax.ATURI, error) {
+
+	if raw == "" {
+		return nil, fmt.Errorf("empty url")
+	}
+
+	// first try simple AT-URI
+	uri, err := syntax.ParseATURI(raw)
+	if nil == err {
+		return &uri, nil
+	}
+
+	// then try bsky.app post URL
+	u, err := url.Parse(raw)
+	if err != nil {
+		return nil, err
+	}
+	if u.Hostname() != "bsky.app" {
+		return nil, fmt.Errorf("only bsky.app URLs currently supported")
+	}
+	pathParts := strings.Split(u.Path, "/") // NOTE: pathParts[0] will be empty string
+	if len(pathParts) != 5 || pathParts[1] != "profile" || pathParts[3] != "post" {
+		return nil, fmt.Errorf("only bsky.app post URLs currently supported")
+	}
+	atid, err := syntax.ParseAtIdentifier(pathParts[2])
+	if err != nil {
+		return nil, err
+	}
+	rkey, err := syntax.ParseRecordKey(pathParts[4])
+	if err != nil {
+		return nil, err
+	}
+	var did syntax.DID
+	if atid.IsHandle() {
+		ident, err := srv.dir.Lookup(ctx, *atid)
+		if err != nil {
+			return nil, err
+		}
+		did = ident.DID
+	} else {
+		did, err = atid.AsDID()
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// TODO: don't really need to re-parse here, if we had test coverage
+	aturi, err := syntax.ParseATURI(fmt.Sprintf("at://%s/app.bsky.feed.post/%s", did, rkey))
+	if err != nil {
+		return nil, err
+	} else {
+		return &aturi, nil
+	}
+}
+
+func (srv *Server) postEmbedHTML(post *appbsky.FeedDefs_PostView) string {
+	aturi, err := syntax.ParseATURI(post.Uri)
+	if err != nil {
+		log.Error("bad AT-URI in reponse", "aturi", aturi)
+	}
+	// TODO: could add language, maybe other fiels here?
+	// XXX: should actually use html/template for this render
+	return fmt.Sprintf(
+		"<iframe src=\"%s\" class=\"bluesky-post-embed\" data-aturi=\"%s\" data-record-cid=\"%s\"></iframe><script src=\"%s\" async=\"async\"></script>",
+		fmt.Sprintf("https://embed.bsky.app/embed/%s/app.bsky.feed.post/%s", post.Author.Did, aturi.RecordKey()),
+		post.Uri,
+		post.Cid,
+		"https://embed.bsky.app/iframe-resize.js",
+	)
+}
+
+func (srv *Server) WebOEmbed(c echo.Context) error {
+	formatParam := c.QueryParam("format")
+	if formatParam != "" && formatParam != "json" {
+		return c.String(http.StatusNotImplemented, "Unsupported oEmbed format: "+formatParam)
+	}
+
+	width := 550
+	maxWidthParam := c.QueryParam("maxwidth")
+	if maxWidthParam != "" {
+		maxWidthInt, err := strconv.Atoi(maxWidthParam)
+		if err != nil || maxWidthInt < 220 || maxWidthInt > 550 {
+			return c.String(http.StatusBadRequest, "Invalid maxwidth (expected integer between 220 and 550)")
+		}
+		width = maxWidthInt
+	}
+	// NOTE: maxheight ignored
+
+	aturi, err := srv.parseBlueskyURL(c.Request().Context(), c.QueryParam("url"))
+	if err != nil {
+		return c.String(http.StatusBadRequest, fmt.Sprintf("Expected 'url' to be bsky.app URL or AT-URI: %v", err))
+	}
+	if aturi.Collection() != syntax.NSID("app.bsky.feed.post") {
+		return c.String(http.StatusNotImplemented, "Only posts (app.bsky.feed.post records) can be embedded currently")
+	}
+	did, err := aturi.Authority().AsDID()
+	if err != nil {
+		return err
+	}
+
+	post, err := srv.getBlueskyPost(c.Request().Context(), did, aturi.RecordKey())
+	if err == ErrPostNotFound {
+		return c.String(http.StatusNotFound, fmt.Sprintf("%v", err))
+	} else if err == ErrPostNotPublic {
+		return c.String(http.StatusForbidden, fmt.Sprintf("%v", err))
+	} else if err != nil {
+		return c.String(http.StatusInternalServerError, fmt.Sprintf("%v", err))
+	}
+
+	data := OEmbedResponse{
+		Type:         "rich",
+		Version:      "1.0",
+		AuthorName:   "@" + post.Author.Handle,
+		AuthorURL:    fmt.Sprintf("https://bsky.app/profile/%s", post.Author.Handle),
+		ProviderName: "Bluesky Social",
+		CacheAge:     86400,
+		Width:        width,
+		Height:       nil,
+		HTML:         srv.postEmbedHTML(post),
+	}
+	if post.Author.DisplayName != nil {
+		data.AuthorName = fmt.Sprintf("%s (@%s)", *post.Author.DisplayName, post.Author.Handle)
+	}
+	return c.JSON(http.StatusOK, data)
+}
+
+func (srv *Server) WebPostEmbed(c echo.Context) error {
+	ctx := c.Request().Context()
+
+	// sanity check arguments. don't 4xx, just let app handle if not expected format
+	rkeyParam := c.QueryParam("rkey")
+	rkey, err := syntax.ParseRecordKey(rkeyParam)
+	if err != nil {
+		return c.String(http.StatusBadRequest, fmt.Sprintf("Invalid RecordKey: %v", err))
+	}
+	didParam := c.QueryParam("did")
+	did, err := syntax.ParseDID(didParam)
+	if err != nil {
+		return c.String(http.StatusBadRequest, fmt.Sprintf("Invalid DID: %v", err))
+	}
+
+	postView, err := srv.getBlueskyPost(ctx, did, rkey)
+	if err == ErrPostNotFound {
+		return c.String(http.StatusNotFound, fmt.Sprintf("%v", err))
+	} else if err == ErrPostNotPublic {
+		return c.String(http.StatusForbidden, fmt.Sprintf("%v", err))
+	} else if err != nil {
+		return c.String(http.StatusInternalServerError, fmt.Sprintf("%v", err))
+	}
+
+	data := map[string]interface{}{
+		"post": postView,
+	}
+	return c.Render(http.StatusOK, "postEmbed.html", data)
+}

bskyweb/cmd/embedr/server.go

@@ -13,8 +13,7 @@ import (
 	"syscall"
 	"time"
 
-	appbsky "github.com/bluesky-social/indigo/api/bsky"
+	"github.com/bluesky-social/indigo/atproto/identity"
-	"github.com/bluesky-social/indigo/atproto/syntax"
 	"github.com/bluesky-social/indigo/util/cliutil"
 	"github.com/bluesky-social/indigo/xrpc"
 	"github.com/bluesky-social/social-app/bskyweb"
@@ -30,6 +29,7 @@ type Server struct {
 	echo  *echo.Echo
 	httpd *http.Server
 	xrpcc *xrpc.Client
+	dir   identity.Directory
 }
 
 func serve(cctx *cli.Context) error {
@@ -71,6 +71,7 @@ func serve(cctx *cli.Context) error {
 	server := &Server{
 		echo:  e,
 		xrpcc: xrpcc,
+		dir:   identity.DefaultDirectory(),
 	}
 
 	// Create the HTTP server.
@@ -140,7 +141,7 @@ func serve(cctx *cli.Context) error {
 			log.Debugf("serving static file from the local file system")
 			return http.FS(os.DirFS("static"))
 		}
-		fsys, err := fs.Sub(bskyweb.StaticFS, "static")
+		fsys, err := fs.Sub(bskyweb.EmbedrStaticFS, "static")
 		if err != nil {
 			log.Fatal(err)
 		}
@@ -172,6 +173,7 @@ func serve(cctx *cli.Context) error {
 
 	// actual routes
 	e.GET("/", server.WebHome)
+	e.GET("/iframe-resize.js", echo.WrapHandler(staticHandler))
 	e.GET("/embed.js", echo.WrapHandler(staticHandler))
 	e.GET("/oembed", server.WebOEmbed)
 	e.GET("/embed/:did/app.bsky.feed.post/:rkey", server.WebPostEmbed)
@@ -232,85 +234,3 @@ func (srv *Server) errorHandler(err error, c echo.Context) {
 	}
 	c.Render(code, "error.html", data)
 }
-
-func (srv *Server) WebHome(c echo.Context) error {
-	data := map[string]interface{}{}
-	return c.Render(http.StatusOK, "home.html", data)
-}
-
-func (srv *Server) WebOEmbed(c echo.Context) error {
-	data := map[string]interface{}{}
-	return c.Render(http.StatusOK, "oembed.html", data)
-}
-
-func (srv *Server) WebPostEmbed(c echo.Context) error {
-	ctx := c.Request().Context()
-	data := map[string]interface{}{}
-
-	// sanity check arguments. don't 4xx, just let app handle if not expected format
-	rkeyParam := c.Param("rkey")
-	rkey, err := syntax.ParseRecordKey(rkeyParam)
-	if err != nil {
-		return c.Render(http.StatusOK, "postEmbed.html", data)
-	}
-	didParam := c.Param("did")
-	did, err := syntax.ParseDID(didParam)
-	if err != nil {
-		return c.Render(http.StatusOK, "postEmbed.html", data)
-	}
-
-	// requires two fetches: first fetch profile (!)
-	pv, err := appbsky.ActorGetProfile(ctx, srv.xrpcc, did.String())
-	if err != nil {
-		log.Warnf("failed to fetch profile for: %s\t%v", did, err)
-		return c.Render(http.StatusOK, "postEmbed.html", data)
-	}
-	unauthedViewingOkay := true
-	for _, label := range pv.Labels {
-		if label.Src == pv.Did && label.Val == "!no-unauthenticated" {
-			unauthedViewingOkay = false
-		}
-	}
-
-	if !unauthedViewingOkay {
-		return c.Render(http.StatusOK, "postEmbed.html", data)
-	}
-	data["did"] = did.String()
-
-	// then fetch the post thread (with extra context)
-	uri := fmt.Sprintf("at://%s/app.bsky.feed.post/%s", did, rkey)
-	tpv, err := appbsky.FeedGetPostThread(ctx, srv.xrpcc, 1, 0, uri)
-	if err != nil {
-		log.Warnf("failed to fetch post: %s\t%v", uri, err)
-		return c.Render(http.StatusOK, "postEmbed.html", data)
-	}
-	req := c.Request()
-	postView := tpv.Thread.FeedDefs_ThreadViewPost.Post
-	data["postView"] = postView
-	data["requestURI"] = fmt.Sprintf("https://%s%s", req.Host, req.URL.Path)
-	if postView.Embed != nil {
-		if postView.Embed.EmbedImages_View != nil {
-			var thumbUrls []string
-			for i := range postView.Embed.EmbedImages_View.Images {
-				thumbUrls = append(thumbUrls, postView.Embed.EmbedImages_View.Images[i].Thumb)
-			}
-			data["imgThumbUrls"] = thumbUrls
-		} else if postView.Embed.EmbedRecordWithMedia_View != nil && postView.Embed.EmbedRecordWithMedia_View.Media != nil && postView.Embed.EmbedRecordWithMedia_View.Media.EmbedImages_View != nil {
-			var thumbUrls []string
-			for i := range postView.Embed.EmbedRecordWithMedia_View.Media.EmbedImages_View.Images {
-				thumbUrls = append(thumbUrls, postView.Embed.EmbedRecordWithMedia_View.Media.EmbedImages_View.Images[i].Thumb)
-			}
-			data["imgThumbUrls"] = thumbUrls
-		}
-	}
-
-	if postView.Record != nil {
-		postRecord, ok := postView.Record.Val.(*appbsky.FeedPost)
-		if ok {
-			_ = postRecord
-			data["postText"] = "" // XXX
-		}
-	}
-
-	return c.Render(http.StatusOK, "postEmbed.html", data)
-}

bskyweb/embedr-static/iframe-resize.js

@@ -0,0 +1 @@
+/* script to resize embed ifame would go here? */

bskyweb/embedr-templates/home.html

@@ -1 +1,8 @@
-embed homepage: could redirect to bsky.app, or show a "create embed" widget
+<html>
+<head>
+</head>
+<body>
+	<h1>embed.bsky.app homepage</h1>
+	<p>could redirect to bsky.app? or show a "create embed" widget?
+</body>
+</html>

bskyweb/static.go

@@ -4,3 +4,6 @@ import "embed"
 
 //go:embed static/*
 var StaticFS embed.FS
+
+//go:embed embedr-static/*
+var EmbedrStaticFS embed.FS