I am using google apps script for a project that automatically posts to Bluesky. It is correctly logging in and getting access. It is correctly creating posts. I have added in functionality to create replies by adding the reply block to the post, with the correct root and parent tags. And I have it posting images correctly (most of the time; I still have issues recognizing when an image is too large, but that’s a different problem). Because all of that works, I will not include any of that code here.

Now I am trying to add in functionality to correctly indicate facets, like mentions, links, and hashtags. Specifically, I’m look at hashtags right now. I suspect if I can get this to work, I can get links and mentions to work as well. However, despite multiple attempts, I’m not getting it to correctly format the hashtag.

I have logic in my script that recognizes that there is a hashtag present. It then sends both the post text and the hashtag text (substring of the post) to a function that is supposed to be returning the starting and ending indices of the hashtag text, so that I can include that in the facet block. Because Bluesky works in UTF-8 and apps script UTF-16, that function does some conversion, to get the UTF-8 indices. I suspect that function could be where some of my problem is, but I’m not sure.

function getUtf8Indices(text, substring) {
  // 1. Convert the UTF-16 string to a byte array using UTF-8 encoding
  var byteArray = Utilities.newBlob(text, 'text/plain; charset=UTF-8').getBytes();

  // 2. Find the starting byte index of the substring
  var byteStartIndex = byteArray.indexOf(Utilities.newBlob(substring, 'text/plain; charset=UTF-8').getBytes()[0]);

  // 3. Calculate the ending byte index
  var byteEndIndex = byteStartIndex + Utilities.newBlob(substring, 'text/plain; charset=UTF-8').getBytes().length - 1; 

  return { byteStart: byteStartIndex, byteEnd: byteEndIndex };
}

That function is called within my block to create the post initially. Here is the section specific to the facet / hashtag process.

if(iRow[7] != "" && iRow[7] != null) {  //is there a hashtag value?
    var indeces = getUtf8Indices(iRow[3], iRow[7])  //pass the whole post & the hashtag value (substring of the post text) to get the start / end indices of the substring
    this.facets = [
      {
        index: {
          byteStart: indeces.byteStart,
          byteEnd: indeces.byteEnd,
        },
        features: [{
          $type: 'app.bsky.richtext.facet#tag',
          tag: iRow[7].replace(/^#/, ''),
        }]
      }
    ]
  }

It does return the indices, and when I Log the characters at the start / end indices, it does identify the start / end of the hashtag string. But then when the post is created on Bluesky, it’s not formatted as a hashtag (string shaded blue), but just as plain text.

I suspect a couple different options.

• I could be missing something really obvious; a typo that I’m just overlooking for example. Or maybe I’m not sending the correct substring (I’ve done it both with and without the ‘#’ as part of the substring, and that doesn’t seem to make a difference).
• Or it could be something in the getUtf8Indices() function. Full disclosure, I didn’t write that function, but copied it from somewhere, so it’s entirely possible that isn’t actually doing what I need it to do.
• Or it could be something else entirely.

I’ve tried a bunch of different things, and nothing has worked. Any suggestions or guidance would be great.