HTML Shell
Experimental. This feature may change or be removed.
The shell is the single HTML file that fills the Custom Dashboard canvas. TagoIO hosts it for you (versioned storage). You do not host a public URL for the dashboard page itself.
There is no in-app HTML editor. Edit the file offline, then upload again.
First upload
Until a shell exists, the dashboard shows an empty state:
- Upload HTML to choose a local
.htmlfile. - A collapsible note with the postMessage snippet so you can wire
dashboard:readycorrectly.
After a successful upload, Admin loads the shell in an iframe and waits for your page to signal ready.
Gear menu (shell actions)
When the dashboard is a Custom Dashboard, the gear menu includes shell actions that Normal and Blueprint dashboards do not have:
| Action | What it does |
|---|---|
| Upload new HTML | Replace the current shell with another local file. |
| Download current HTML | Save the hosted shell as a local .html file for offline edit. |
Use download, edit locally, then upload new HTML as the normal edit loop.
Data is not configured in the gear menu. Your shell lists and runs saved queries over the postMessage SQL bridge.
Version restore
Dashboard version restore works for the shell. Restoring a version can return a previous HTML upload (or clear the shell if that version had none). After restore, Admin reloads the canvas to match what is stored.
Restore applies to the shell and other dashboard record fields through the same version tooling as other dashboard types.
API surface (shell)
Most authors stay in Admin. If you automate shell upload:
| Method | Path | Notes |
|---|---|---|
PUT | /dashboard/{id}/html | Body is raw HTML (Content-Type: text/html). Profile token required. |
GET | /dashboard/{id}/html | Returns the hosted shell. Auth via short-lived html_access (exp + sig) from dashboard info, or a token query parameter. |
Full request details live in the TagoIO API reference under dashboards.
Tips
- Ship a single file: inline CSS and JS, or load third-party assets from absolute HTTPS URLs your page is allowed to use.
- Post
dashboard:readyonly after listeners are registered so you do not miss the first host messages. See Authoring HTML. - Prefer download + re-upload over hand-editing production shells from memory.