Truncate data from OpenGraph metadata (#10532)

* Truncate strings from OpenGraph metada

* remove unwanted opengraph fields, limit to 1 image

* test helper functions

* Add truncating test

* fix typo

* change test into not comparing for the pointer value

* truncate only once

* only shorten fields that were already present

* set maximum of 5 images

* fix original tests

* fix test

* limit to 5 images

* fix typo

* place functions below types, simplify function commentaries

* Rewrite how to empty opengraph's structure

app/post_metadata.go

@@ -379,6 +379,7 @@ func (a *App) getLinkMetadata(requestURL string, timestamp int64, isNewPost bool
 		// Parse the data
 		og, image, err = a.parseLinkMetadata(requestURL, body, contentType)
 	}
+	og = model.TruncateOpenGraph(og) // remove unwanted length of texts
 
 	// Write back to cache and database, even if there was an error and the results are nil
 	cacheLinkMetadata(requestURL, timestamp, og, image)

app/post_metadata_test.go

@@ -230,7 +230,7 @@ func TestPreparePostForClient(t *testing.T) {
 
 		clientPost := th.App.PreparePostForClient(post, false, false)
 
-		t.Run("pupulates emojis", func(t *testing.T) {
+		t.Run("populates emojis", func(t *testing.T) {
 			assert.ElementsMatch(t, []*model.Emoji{emoji1, emoji2, emoji3, emoji4}, clientPost.Metadata.Emojis, "should've populated post.Emojis")
 		})
 
@@ -331,26 +331,18 @@ func TestPreparePostForClient(t *testing.T) {
 		require.Nil(t, err)
 
 		clientPost := th.App.PreparePostForClient(post, false, false)
+		firstEmbed := clientPost.Metadata.Embeds[0]
+		ogData := firstEmbed.Data.(*opengraph.OpenGraph)
 
 		t.Run("populates embeds", func(t *testing.T) {
-			assert.ElementsMatch(t, []*model.PostEmbed{
-				{
-					Type: model.POST_EMBED_OPENGRAPH,
-					URL:  "https://github.com/hmhealey/test-files",
-					Data: &opengraph.OpenGraph{
-						Description: "Contribute to hmhealey/test-files development by creating an account on GitHub.",
-						SiteName:    "GitHub",
-						Title:       "hmhealey/test-files",
-						Type:        "object",
-						URL:         "https://github.com/hmhealey/test-files",
-						Images: []*opengraph.Image{
-							{
-								URL: "https://avatars1.githubusercontent.com/u/3277310?s=400&v=4",
-							},
-						},
-					},
-				},
-			}, clientPost.Metadata.Embeds)
+			assert.Equal(t, firstEmbed.Type, model.POST_EMBED_OPENGRAPH)
+			assert.Equal(t, firstEmbed.URL, "https://github.com/hmhealey/test-files")
+			assert.Equal(t, ogData.Description, "Contribute to hmhealey/test-files development by creating an account on GitHub.")
+			assert.Equal(t, ogData.SiteName, "GitHub")
+			assert.Equal(t, ogData.Title, "hmhealey/test-files")
+			assert.Equal(t, ogData.Type, "object")
+			assert.Equal(t, ogData.URL, "https://github.com/hmhealey/test-files")
+			assert.Equal(t, ogData.Images[0].URL, "https://avatars1.githubusercontent.com/u/3277310?s=400&v=4")
 		})
 
 		t.Run("populates image dimensions", func(t *testing.T) {