frontend: change logic of when doc links are shown in search results

app/components/crate-row.hbs

@@ -61,12 +61,12 @@
     {{#if @crate.homepage}}
       <li><a href="{{@crate.homepage}}">Homepage</a></li>
     {{/if}}
-    {{#if @crate.documentation}}
-      <li><a href="{{@crate.documentation}}">Documentation</a></li>
+    {{#if @crate.documentationLink}}
+      <li><a href="{{@crate.documentationLink}}">Documentation</a></li>
     {{/if}}
     {{#if @crate.repository}}
       <li><a href="{{@crate.repository}}">Repository</a></li>
     {{/if}}
   </ul>
 
-</div>
+</div>

app/controllers/search.js

@@ -3,9 +3,10 @@
 import { inject as service } from '@ember/service';
 import { tracked } from '@glimmer/tracking';
 
-import { restartableTask } from 'ember-concurrency';
+import { all, restartableTask } from 'ember-concurrency';
 import { bool, reads } from 'macro-decorators';
 
+import { AjaxError } from '../utils/ajax';
 import { pagination } from '../utils/pagination';
 import { CATEGORY_PREFIX, processSearchQuery } from '../utils/search';
 
@@ -73,6 +74,22 @@
       ? { page, per_page, sort, q: query, all_keywords }
       : { page, per_page, sort, ...processSearchQuery(query) };
 
-    return await this.store.query('crate', searchOptions);
+    const crates = await this.store.query('crate', searchOptions);
+
+    // Prime the docs for the most recent versions of each crate.
+    const docTasks = [];
+    for (const crate of crates) {
+      docTasks.push(crate.loadDocsStatusTask.perform());
+    }
+    try {
+      await all(docTasks);
+    } catch (e) {
+      // report unexpected errors to Sentry and ignore `ajax()` errors
+      if (!didCancel(error) && !(error instanceof AjaxError)) {
+        this.sentry.captureException(error);
+      }
+    }
+
+    return crates;
   });
 }

app/models/crate.js

@@ -1,9 +1,12 @@
 import Model, { attr, hasMany } from '@ember-data/model';
 import { waitForPromise } from '@ember/test-waiters';
 
+import { task } from 'ember-concurrency';
 import { apiAction } from '@mainmatter/ember-api-actions';
 import { cached } from 'tracked-toolbox';
 
+import ajax from '../utils/ajax';
+
 export default class Crate extends Model {
   @attr name;
   @attr downloads;
@@ -42,6 +45,45 @@
     }
   }
 
+  get documentationLink() {
+    let crateDocsLink = this.documentation;
+
+    // if this is *not* a docs.rs link we'll return it directly
+    if (crateDocsLink && !crateDocsLink.startsWith('https://docs.rs/')) {
+      return crateDocsLink;
+    }
+
+    // if we know about a successful docs.rs build, we'll return a link to that
+    let { docsRsLink } = this;
+    if (docsRsLink) {
+      return docsRsLink;
+    }
+
+    // finally, we'll return the specified documentation link, whatever it is
+    if (crateDocsLink) {
+      return crateDocsLink;
+    }
+
+    return null;
+  }
+
+  loadDocsStatusTask = task(async () => {
+    if (!this.documentation) {
+      return await ajax(`https://docs.rs/crate/${this.name}/=${this.defaultVersion}/status.json`);
+    }
+  });
+
+  get hasDocsRsLink() {
+    let docsStatus = this.loadDocsStatusTask.lastSuccessful?.value;
+    return docsStatus?.doc_status === true;
+  }
+
+  get docsRsLink() {
+    if (this.hasDocsRsLink) {
+      return `https://docs.rs/${this.name}`;
+    }
+  }
+
   @cached get versionIdsBySemver() {
     let versions = this.versions.toArray() ?? [];
     return versions.sort(compareVersionBySemver).map(v => v.id);