5 files changed, 244 insertions, 0 deletions
diff --git a/ops/gerrit-tvl/HttpModule.java b/ops/gerrit-tvl/HttpModule.java
new file mode 100644
index 000000000000..6d785c0817fc
--- /dev/null
+++ b/ops/gerrit-tvl/HttpModule.java
@@ -0,0 +1,14 @@
+package su.tvl.gerrit;
+
+import com.google.gerrit.extensions.registration.DynamicSet;
+import com.google.gerrit.extensions.webui.JavaScriptPlugin;
+import com.google.gerrit.extensions.webui.WebUiPlugin;
+import com.google.inject.servlet.ServletModule;
+
+public final class HttpModule extends ServletModule {
+
+  @Override
+  protected void configureServlets() {
+    DynamicSet.bind(binder(), WebUiPlugin.class).toInstance(new JavaScriptPlugin("tvl.js"));
+  }
+}
diff --git a/ops/gerrit-tvl/MANIFEST.MF b/ops/gerrit-tvl/MANIFEST.MF
new file mode 100644
index 000000000000..bfe4eedeb6ac
--- /dev/null
+++ b/ops/gerrit-tvl/MANIFEST.MF
@@ -0,0 +1,2 @@
+Gerrit-HttpModule: su.tvl.gerrit.HttpModule
+Gerrit-PluginName: tvl
diff --git a/ops/gerrit-tvl/README.md b/ops/gerrit-tvl/README.md
new file mode 100644
index 000000000000..1b88600f197f
--- /dev/null
+++ b/ops/gerrit-tvl/README.md
@@ -0,0 +1,6 @@
+# gerrit-tvl
+
+A Gerrit plugin that does TVL-specific things.
+
+You probably want to take inspiration from this rather than using it directly,
+as it has a variety of TVL-ish assumptions baked into it.
diff --git a/ops/gerrit-tvl/default.nix b/ops/gerrit-tvl/default.nix
new file mode 100644
index 000000000000..f3bec7a3a242
--- /dev/null
+++ b/ops/gerrit-tvl/default.nix
@@ -0,0 +1,33 @@
+{ depot, pkgs, lib, ... }:
+
+let
+  classPath = lib.concatStringsSep ":" [
+    "${depot.third_party.gerrit}/share/api/extension-api_deploy.jar"
+  ];
+in
+pkgs.stdenvNoCC.mkDerivation rec {
+  name = "${pname}-${version}.jar";
+  pname = "gerrit-tvl";
+  version = "0.0.1";
+
+  src = ./.;
+
+  nativeBuildInputs = with pkgs; [
+    jdk
+  ];
+
+  buildPhase = ''
+    mkdir $NIX_BUILD_TOP/build
+
+    # Build Java components.
+    export JAVAC="javac -cp ${classPath} -d $NIX_BUILD_TOP/build --release 11"
+    $JAVAC ./HttpModule.java
+
+    # Install static files.
+    cp -R static $NIX_BUILD_TOP/build/static
+  '';
+
+  installPhase = ''
+    jar --create --file $out --manifest $src/MANIFEST.MF -C $NIX_BUILD_TOP/build .
+  '';
+}
diff --git a/ops/gerrit-tvl/static/tvl.js b/ops/gerrit-tvl/static/tvl.js
new file mode 100644
index 000000000000..684636de3084
--- /dev/null
+++ b/ops/gerrit-tvl/static/tvl.js
@@ -0,0 +1,189 @@
+// vim: set noai ts=2 sw=2 et: */
+
+// This is a read-only Buildkite token: it was generated by lukegb@, and has
+// read_builds, read_build_logs, and read_pipelines permissions.
+const BUILDKITE_TOKEN = 'a150658fb61062e432f13a032962d70fa9352088';
+
+function encodeParams(p) {
+  const pieces = [];
+  for (let k of Object.getOwnPropertyNames(p)) {
+    pieces.push(`${encodeURIComponent(k)}=${encodeURIComponent(p[k])}`);
+  }
+  return pieces.join('&');
+}
+
+function formatDuration(from, to) {
+  const millisecondsTook = Math.floor(to.valueOf() - from.valueOf());
+  if (millisecondsTook < 2000) return `${millisecondsTook} ms`;
+  const secondsTook = Math.floor(millisecondsTook / 1000);
+  if (secondsTook < 100) return `${secondsTook} seconds`;
+  const minutesTook = Math.floor(secondsTook / 60);
+  if (minutesTook < 60) return `${minutesTook} minutes`;
+  const hoursTook = Math.floor(minutesTook / 60);
+  const minutesRemainder = minutesTook - (hoursTook * 60);
+  return `${hoursTook}hr ${minutesRemainder}min`;
+}
+
+// Maps the status of a Buildkite *job* to the statuses available for
+// a Gerrit check.
+//
+// Note that jobs can have statuses that, according to the Buildkite
+// documentation, are only available for builds, and maybe vice-versa.
+// To deal with this we simply cover all statuses for all types here.
+//
+// Buildkite job statuses: https://buildkite.com/docs/pipelines/notifications#job-states
+//
+// Gerrit check statuses: https://gerrit.googlesource.com/gerrit/+/v3.4.0/polygerrit-ui/app/api/checks.ts#167
+//
+// TODO(tazjin): Use SCHEDULED status once we have upgraded Gerrit
+// past 3.4
+function jobStateToCheckRunStatus(state) {
+  const status = {
+    // Statuses documented for both types
+    'blocked': 'RUNNABLE',
+    'canceled': 'COMPLETED',
+    'canceling': 'RUNNING',
+    'running': 'RUNNING',
+    'scheduled': 'RUNNABLE',
+    'skipped': 'COMPLETED',
+
+    // Statuses only documented for builds
+    'creating': 'RUNNABLE',
+    'failed': 'COMPLETED',
+    'not_run': 'COMPLETED',
+    'passed': 'COMPLETED',
+
+    // Statuses only documented for jobs
+    'accepted': 'RUNNABLE',
+    'assigned': 'RUNNABLE',
+    'blocked_failed': 'COMPLETED',
+    'broken': 'COMPLETED',
+    'finished': 'COMPLETED',
+    'limited': 'RUNNABLE',
+    'limiting': 'RUNNABLE',
+    'pending': 'RUNNABLE',
+    'timed_out': 'COMPLETED',
+    'timing_out': 'RUNNING',
+    'unblocked': 'RUNNABLE',
+    'unblocked_failed': 'COMPLETED',
+    'waiting': 'RUNNABLE',
+    'waiting_failed': 'COMPLETED',
+  }[state];
+
+  if (!status) {
+    console.log(`unknown Buildkite job state: ${state}`);
+  }
+
+  return status;
+}
+
+const tvlChecksProvider = {
+  async fetch(change) {
+    let {patchsetSha, repo} = change;
+
+    const experiments = window.ENABLED_EXPERIMENTS || [];
+    if (experiments.includes("UiFeature__tvl_check_debug")) {
+      patchsetSha = '76692104f58b849b1503a8d8a700298003fa7b5f';
+      repo = 'depot';
+    }
+
+    if (repo !== 'depot') {
+      // We only handle TVL's depot at the moment.
+      return {responseCode: 'OK'};
+    }
+
+    const params = {
+      commit: patchsetSha,
+    };
+    const url = `https://api.buildkite.com/v2/organizations/tvl/pipelines/depot/builds?${encodeParams(params)}`;
+    const resp = await fetch(url, {
+      headers: {
+        Authorization: `Bearer ${BUILDKITE_TOKEN}`,
+      },
+    });
+    const respJSON = await resp.json();
+
+    const runs = [];
+    for (let i = 0; i < respJSON.length; i++) {
+      const attempt = respJSON.length - i;
+      const build = respJSON[i];
+
+      for (let job of build.jobs) {
+        // Skip non-command jobs (e.g. waiting/grouping jobs)
+        if (job.type !== 'script') {
+          continue;
+        }
+
+        // Skip jobs marked as 'broken' (this means they were skipped
+        // intentionally)
+        if (job.state === 'broken') {
+          continue;
+        }
+
+        // TODO(lukegb): add the ability to retry these
+        const checkRun = {
+          patchset: parseInt(build.env.GERRIT_PATCHSET, 10),
+          attempt: attempt,
+          externalId: job.id,
+          checkName: job.name,
+          checkDescription: job.command,
+          checkLink: job.web_url,
+          status: jobStateToCheckRunStatus(job.state),
+          labelName: 'Verified',
+        };
+
+        if (job.scheduled_at) {
+          checkRun.scheduledTimestamp = new Date(job.scheduled_at);
+        }
+
+        if (job.started_at) {
+          checkRun.startedTimestamp = new Date(job.started_at);
+        }
+
+        if (job.finished_at) {
+          checkRun.finishedTimestamp = new Date(job.finished_at);
+        }
+
+        let statusDescription = job.state;
+        if (checkRun.startedTimestamp && checkRun.finishedTimestamp) {
+          statusDescription = `${statusDescription} in ${formatDuration(checkRun.startedTimestamp, checkRun.finishedTimestamp)}`;
+        } else if (checkRun.startedTimestamp) {
+          statusDescription = `${statusDescription} for ${formatDuration(checkRun.startedTimestamp, new Date())}`;
+        } else if (checkRun.scheduledTimestamp) {
+          statusDescription = `${statusDescription} for ${formatDuration(checkRun.scheduledTimestamp, new Date())}`;
+        }
+        checkRun.statusDescription = statusDescription;
+
+        if (['failed', 'timed_out'].includes(job.state)) {
+          const result = {
+            // TODO(lukegb): get the log as the message here (the Gerrit
+            // implementation doesn't yet seem to support newlines in message
+            // strings...)
+            links: [{
+              url: job.web_url,
+              tooltip: "Buildkite",
+              primary: true,
+              icon: 'EXTERNAL',
+            }],
+            category: 'ERROR',
+            summary: `${job.command} failed`,
+          };
+          checkRun.results = [result];
+        }
+
+        runs.push(checkRun);
+      }
+    }
+
+    return {
+      responseCode: 'OK',
+      runs: runs,
+    };
+  },
+};
+
+Gerrit.install(plugin => {
+  console.log('TVL plugin initialising');
+
+  plugin.checks().register(tvlChecksProvider);
+});