Adapters API

@diazoma/adapters has feed adapters for the wall. Each one implements FeedAdapter and only fetches and parses. It never renders, and the cursors it returns are opaque strings.

Adapter	Reads	Cursor
`JsonFeedAdapter({ url, search?, filters?, fetch? })`	a feed of the spec: `{ items, next }`	the server’s `next`, verbatim
`WellKnownAdapter({ origin })`	`/.well-known/wall.json` (or `<link rel="wall-manifest">`). Builds a `JsonFeedAdapter` per feed and exposes `brand`, `policy`, filters and actions	`base64url(JSON { f: feed id, c: server cursor })`
`DomAdapter({ root?, mode? })`	the page itself: `[data-wall-item]`, then JSON-LD, then clusters of similar siblings	`base64url(JSON { u: next url })`, or `{ p: n }` for infinite scroll
`RssAdapter({ url })`	RSS 2.0 and Atom	none, unless the feed has `<atom:link rel="next">`
`RecipeAdapter({ recipe })`	a recipe from `@diazoma/recipe-schema`: a JSON API (JSONPath, no eval) or the DOM (CSS selectors)	`base64url(JSON { page })` or `{ u }`

import { WellKnownAdapter } from '@diazoma/adapters';

const adapter = await new WellKnownAdapter({ origin: location.origin }).ready();
new Wall({ mount, adapter, brand: adapter.brand });

WellKnownAdapter.capabilities() is synchronous, so call ready() before you pass the adapter to the wall.

Options worth knowing

DomAdapter mode: auto (the default), annotated, jsonld or heuristic. auto tries them in that order and stops at the first that finds items.
JsonFeedAdapter filters take { key, values, param? }. param is the query parameter, and defaults to key.
RssAdapter sizes is a function from an absolute image URL to smaller copies. See Image sizes.
Every adapter takes fetch (to replace the global one) and onWarning (to hear about dropped items).
RecipeAdapter source forces api or dom.

Invalid items are dropped and reported through onWarning. A manifest with "policy": "deny" makes page() reject with an AdapterError whose code is policy-denied.

The site’s view

Every adapter that reads a site description also passes on the site’s view: WellKnownAdapter from manifest.view, RecipeAdapter from recipe.view, and DomAdapter from the first <script type="application/json" data-wall-view> on the page. A panorama that is not an absolute http(s) URL is dropped.

WellKnownAdapter also sets login (from auth.login) and capabilities().links: the actions with mode: "deeplink".

Smaller images

Every adapter looks for smaller images when an item brings only image. See Image sizes.

Node entry: `@diazoma/adapters/node`

Adapters use the global DOMParser. In a browser that is built in. In Node, call installDom() from @diazoma/adapters/node first. It installs linkedom’s.

runFixtures(recipe, dir) replays each fixture of a recipe through RecipeAdapter with a fixture-backed fetch, and checks at least one item with id, link, image and aspect. The diazoma-recipe run <recipe.json> command does the same from a shell and exits 1 on a failure. See Recipes.

Browser bundle

dist/adapters.iife.js exposes window.DiazomaAdapters for pages without a bundler.