feat: add fromURL

README.md

@@ -118,6 +118,23 @@ You can also mix and match the parameter styles, however you like.
 {{/let}}
 ```
 
+##### `fromURL`
+
+Instead of the positional & named link parameters described above, you can also
+create a `Link` instance from a serialized URL.
+
+```hbs
+{{! someURL = "/blogs/tech/posts/dont-break-the-web" }}
+{{#let (link fromURL=this.someURL) as |l|}}
+  <a href={{l.url}} {{on "click" l.transitionTo}}>
+    Read the next great post.
+  </a>
+{{/let}}
+```
+
+`fromURL` is mutually exclusive with the other link parameters: `route`, `model`
+& `models`, `query`
+
 ### Parameters
 
 In addition to the parameters shown above, the `{{link}}` helper also accepts a
@@ -280,6 +297,25 @@ Query Params object.
 {{/link-to}}
 ```
 
+##### `@fromURL`
+
+Optional. Mutually exclusive with [`@route`](#route), [`@model`](#model) /
+[`@models`](#models), [`@query`](#query).
+
+**Example**
+
+```hbs
+<Link @fromURL="/blogs/tech/posts/dont-break-the-web" as |l|>
+  <a
+    href={{l.href}}
+    class={{if l.isActive "is-active"}}
+    {{on "click" l.transitionTo}}
+  >
+    Click me
+  </a>
+</Link>
+```
+
 ##### `@preventDefault`
 
 Optional. Default: `true`

addon/components/link/template.hbs

@@ -4,6 +4,7 @@
     models=@models
     model=@model
     query=@query
+    fromURL=@fromURL
     preventDefault=@preventDefault
   )
 ~}}

addon/helpers/link.ts

@@ -22,6 +22,14 @@ export interface LinkHelperNamedParams
    * Optional shortcut for `models={{array model}}`.
    */
   model?: RouteModel;
+
+  /**
+   * Instead of any of the other `LinkParams` used to construct a
+   * `LinkInstance`, you can also provide a serialized URL instead.
+   *
+   * This is mutually exclusive with any other `LinkParams`.
+   */
+  fromURL?: string;
 }
 
 export default class LinkHelper extends Helper {
@@ -47,6 +55,20 @@ export default class LinkHelper extends Helper {
       !('routeName' in named)
     );
 
+    if (named.fromURL) {
+      assert(
+        `When specifying a serialized 'fromURL' ('${named.fromURL}'), you can't provide any further 'LinkParams'.`,
+        !([
+          'route',
+          'models',
+          'model',
+          'query'
+        ] as (keyof LinkHelperNamedParams)[]).some(name => named[name])
+      );
+
+      return this.linkManager.getLinkPramsFromURL(named.fromURL);
+    }
+
     assert(
       `Either pass the target route name as a positional parameter ('${positional[0]}') or pass it as a named parameter ('${named.route}').`,
       !(positional[0] && named.route)

addon/services/link-manager.ts

@@ -1,5 +1,6 @@
 import { action } from '@ember/object';
 import { addListener, removeListener } from '@ember/object/events';
+import RouteInfo from '@ember/routing/-private/route-info';
 import Transition from '@ember/routing/-private/transition';
 import RouterService from '@ember/routing/router-service';
 import Service from '@ember/service';
@@ -8,6 +9,10 @@ import { tracked } from '@glimmer/tracking';
 
 import Link, { LinkParams, UILinkParams, UILink } from '../link';
 
+interface RouterServiceWithRecognize extends RouterService {
+  recognize(url: string): RouteInfo;
+}
+
 export default class LinkManagerService extends Service {
   @tracked
   private _currentTransitionStack?: Transition[];
@@ -16,7 +21,7 @@ export default class LinkManagerService extends Service {
    * The `RouterService` instance to be used by the generated `Link` instances.
    */
   @service('router')
-  readonly router!: RouterService;
+  readonly router!: RouterServiceWithRecognize;
 
   /**
    * Whether the router has been initialized.
@@ -50,6 +55,29 @@ export default class LinkManagerService extends Service {
     return new UILink(this, { ...linkParams, ...uiParams });
   }
 
+  /**
+   * Deserializes the `LinkParams` to be passed to `createLink` / `createUILink`
+   * from a URL.
+   *
+   * If the URL cannot be recognized by the router, an error is thrown.
+   */
+  getLinkPramsFromURL(url: string): LinkParams {
+    const routeInfo = this.router.recognize(url);
+    return LinkManagerService.getLinkParamsFromRouteInfo(routeInfo);
+  }
+
+  /**
+   * Converts a `RouteInfo` object into `LinkParams`.
+   */
+  static getLinkParamsFromRouteInfo(routeInfo: RouteInfo): LinkParams {
+    const models = routeInfo.paramNames.map(name => routeInfo.params[name]!);
+    return {
+      route: routeInfo.name,
+      query: routeInfo.queryParams,
+      models
+    };
+  }
+
   constructor(properties?: object) {
     super(properties);
 

tests/acceptance/link-test.ts

@@ -421,20 +421,19 @@ module('Acceptance | link', function(hooks) {
       );
   });
 
-  test('toString()', async function(this: TestContext, assert) {
+  test('fromURL', async function(this: TestContext, assert) {
     this.Router.map(function() {
-      this.route('foo');
-      this.route('bar');
+      this.route('foo', { path: 'foo/:id' });
     });
 
     this.owner.register(
       'template:application',
-      hbs`{{get (link "foo" query=(hash bar=(link "bar"))) "url"}}`
+      hbs`{{get (link fromURL="/foo/123?bar=qux") "url"}}`
     );
 
     await visit('/');
     assert.equal(currentURL(), '/');
 
-    assert.dom().hasText('/foo?bar=%2Fbar');
+    assert.dom().hasText('/foo/123?bar=qux');
   });
 });