Image upload code for making a Bluesky post.

atproto_image.js

                    // Provide a uint8array of image data and set MIME type.
                    // Bluesky only supports jpg and png at the moment.
                    const testUpload = await agent.uploadBlob(testPng, {encoding: "image/png"})
 
                    // The response contains a BlobRef object, which is what
                    // agent.post expects.
                    const result = await agent.post({
                        text: 'Post Text',
                        reply: {
                            parent: {
                                uri: notif.uri,
                                cid: notif.cid,
                            },
                            root: {
                              uri: notif.uri,
                              cid: notif.cid,
                            },
                        },
                        embed: {
                            images: [
                                {
                                    image: testUpload.data.blob,
                                    alt: "",
                                },
                            ],
                            $type: "app.bsky.embed.images",
                        },
                    });