The extension does a few things:
- Parses webpages you visit for schema.org entities, and provides that data to Arcs.
- Allows webpages to specify manifests that are loaded into your Arcs instance.
- Provides an entry point to Arcs.
The extension reads out schema.org-compatible data from web pages that are open when you activate the extension (by opening a new tab, activating the browser action, or manually). When you accept suggestions that contain those stores, they are synchronized to a public firebase.
Eventually, the sync will be to your private data store (perhaps firebase, but other options will be available).
Please be aware of this limitation as you think about what sites to visit while using this extension. A best practice until these limitations are removed is to use this in a non-primary profile or a secondary browser.
Load the extension as an 'unpacked extension' at chrome://extensions.
As mentioned above, Arcs consumes metadata from the browser in the background at Arcs extensions startup and when a new page loads.
The extension is visible in two places:
- A browser action (an icon to the right of the address bar). Clicking this will read additional data from the current page (like the address) into the Arcs context and will open Arcs in a popup.
- Opening a new tab will open Arcs.
Custom actions may be visible on some pages that you visit. Try the index-with-arcs in the arcs-custom-events repository.
Manifests can be embedded into web pages, allowing sites to extend Arcs with additional custom functionality or data types. This is done via a link element as in this example:
<link rel="arcs-manifest" type="text/x-arcs-manifest"
href="arcs/custom.manifest">
This will load the manifest as arcs/custom.manifest into Arcs instances that
are triggered from the browser (either via the popup or new tab).
Unit tests can be run in browser by opening index.test.html or on the command
line (from arcs) with tools/install && npm test.
For manual testing, there are a few scenarios that should reliably work after enabling the extension.
- Visit a page with embedded data. Products
such as Google Cardboard
is an easy option. Verify that:
- The 'arc' logo appears on the Browser Action.
- Clicking on the Browser Action includes your sample data (in my case, Google Cardboard) in a recipe. For a product, try the "Buy products" recipe. If too many things appear, go full-screen and disable any extra recipes.
- Open the New Tab, and verify it has access to the information from all tabs. Open another product (such as LG Watch and verify that shows up in the arc.
- Visit a page with an embedded manifest like index-with-arcs. Verify that the custom actions appear.
The extension automatically tags [Product] with #shortlist, and all other stores with #browserContext.
Nothing is ever complete.
- Tags are how we differentiate between stores. Once firebase supports it, put additional tags on all stores created by the extension (as many as possible - the more information in tags, the better matches we'll be able to find).
- De-duplicate data - some pages embed entities multiple times, and reloads can cause the same information to be in the store many times. Keep track of what we've sent and only send new entities.