n8n Instagram & Facebook Auto-Posting, Driven by a Google Sheet

The queue is just a Sheet, on purpose

The VideoQueue tab has seven columns: video_key, title, video_url, fb_caption, ig_caption, status, published_at. No dashboard, no separate app — anyone who can edit a spreadsheet can queue up a week of content. The Code node's whole job is to grab the rows with status == 'ready' and take the first one, so the order in the sheet is the order it posts.

Matching by video_key, not row number

Early on I matched updates by row position, and it went wrong the first time someone (me) reordered rows while a run was in flight. Now every match — reading which row is next, writing back that it published — goes through video_key, a stable string I set once per video. Row position drifts. Keys don't.

The part that actually needs the Graph API

Facebook Page posting is a straightforward POST /{'{page-id}'}/videos with a file_url and a description. Instagram is a two-step dance: first POST /{'{ig-id}'}/media with media_type: REELS, the video URL, and a caption, which hands back a creation_id — then a second call, POST /{'{ig-id}'}/media_publish, to actually publish it. In between, I wait 45 seconds flat rather than polling the container's processing status. That's an honest shortcut: it works fine for short 15-20 second clips, but a longer video would need real status polling instead of a fixed wait — I just haven't needed it yet for what I'm posting.

The gotcha nobody mentions: video hosting

Both Graph API endpoints fetch the video by URL server-side — there's no simple direct-binary-upload path through this flow. So the video needs to already be sitting somewhere with a real public HTTPS URL before either request goes out. I didn't stand up a separate video host for this: the finished MP4s just get copied into the same nginx docroot that already serves the rest of the site, so they're immediately reachable at a normal URL. One less moving part.

Closing the loop

Once both platforms confirm, a Merge node combines the results, the Sheet row flips to published with a timestamp, and a Telegram message tells me it happened — or, more usefully, tells me when one side succeeded and the other didn't.