feat(contrib/frontend/gerrit): design a simple status & check frontend for Gerrit

It uses imaginary APIs for now, but it's OK.

This has showed up a bunch of generalizations we will need in our own
API.

Signed-off-by: Raito Bezarius <masterancpp@gmail.com>

contrib/checks-ofborg.js

@@ -0,0 +1,88 @@
+/* Inspired from the Lix setup.
+ * Inspired from the Buildbot setup.
+ *
+ * Designed for OfBorg custom checks & server API.
+ * Original-Author: puckipedia
+ */
+Gerrit.install((plugin) => {
+  const serverInfo = plugin.serverInfo();
+  const { statcheck_base_uri, enabled_projects } = serverInfo.plugin;
+  const configuration = {
+    baseUri: statcheck_base_uri,
+    // TODO: use directly ofborg API for this.
+    supportedProjects: enabled_projects,
+  };
+
+  function makeStatcheckUri(suffix) {
+    return `${configuration.baseUri}/${suffix}`;
+  }
+
+  let checksProvider;
+  checksProvider = {
+    async fetch({ repo, patchsetSha, changeNumber, patchsetNumber }, runBefore = false) {
+      if (!configuration.supportedProjects.includes(repo)) {
+        return { responseCode: 'OK' };
+      }
+
+      let num = changeNumber.toString(10);
+
+      // Iterate over all check runs.
+      let checksFetch = await fetch(makeStatcheckUri(`changes/${num}/versions/${patchsetNumber}/checks`), { credentials: 'include' });
+      if (checksFetch.status === 400) {
+        if ((await checksFetch.json()).error === 'invalid origin' && !runBefore) {
+          return await checksProvider.fetch({ repo, patchsetSha, changeNumber, patchsetNumber }, true);
+        }
+
+        return { responseCode: 'OK' }
+      } else if (checksFetch.status === 403) {
+        console.warn(`Failed to fetch change '${changeNumber}' for authorization reasons, automatic login is still a WIP.`);
+        return { responseCode: 'NOT_LOGGED_IN', loginCallback() {
+        } };
+      }
+
+      let checks = await checksFetch.json();
+      if (checks.length === 0) {
+        return { responseCode: 'OK' };
+      }
+
+      let runs = [];
+      let links = [];
+
+      for (let check of checks) {
+        let checkrun = {
+          attempt: check.id,
+          checkName: check.name,
+          externalId: check.id,
+          status: check.status,
+          checkLink: null, // TODO: have a proper and nice web URI
+          labelName: 'Verified', // TODO: generalize what label a check affects.
+          results: [],
+          links: [], // TODO: have a proper web uri
+        };
+
+        if (check.started_at !== null) {
+          checkrun.startedTimestamp = new Date(check.started_at * 1000);
+        }
+
+        if (check.completed_at !== null) {
+          checkrun.finishedTimestamp = new Date(check.completed_at * 1000);
+        }
+
+        if (check.results !== null) {
+          checkrun.results = [
+            {
+              category: "SUCCESS",
+              summary: check.summary
+            }
+          ];
+        }
+
+        runs.push(checkrun);
+      }
+
+      return { responseCode: 'OK', runs, links };
+    }
+  };
+
+  plugin.checks().register(checksProvider);
+});