Make grafana prefer the vault's password, and let the secrets list only shrink (hq issue 342)

grafana's client logged in with a token setting ahead of the vault's admin password,
and its runtime config let a layer set token. The token setting is now ignored and
said, token is protected, and the vault's password comes first.

checks/secrets/known could gain a line hiding a newly unprotected key. merge-check.sh
now judges it against the trunk's copy at the merge base, and refuses an added line.

modules/grafana/client.ts

@@ -44,6 +44,17 @@ function meshConfig(file?: string): Record<string, string> {
   catch { return {}; }
 }
 
+/**
+ * A password, token or API key is the vault's, never a setting (novox/hq issue 342): a value for one of
+ * them in the settings file is ignored, and that is said once — by its key, never with its value.
+ */
+const saidIgnored = new Set<string>();
+function ignoreSecretSetting(cfg: Record<string, unknown>, key: string): void {
+  if (cfg[key] === undefined || saidIgnored.has(key)) return;
+  saidIgnored.add(key);
+  console.error(`the setting ${key} is ignored: it comes from the vault`);
+}
+
 export class GrafanaClient {
   readonly baseUrl: string;
   private readonly authHeader: string;
@@ -54,21 +65,24 @@ export class GrafanaClient {
   }
 
   /**
-   * Build from the module's resolved environment. Auth is a service-account/API token
-   * (MESH_GRAFANA_TOKEN, sent as Bearer) when present, else HTTP basic with the admin password the
-   * module keeps as its own secret (MESH_GRAFANA_PASSWORD, user MESH_GRAFANA_USER, default admin).
-   * Throws when neither is configured — the module then contributes nothing rather than failing.
+   * Build from the module's resolved environment. Auth is HTTP basic with the vault's admin password,
+   * which the runtime config carries as `password` (kept protected, so no setting replaces it) or
+   * MESH_GRAFANA_PASSWORD (user MESH_GRAFANA_USER, default admin); else a service-account/API token from
+   * the environment (MESH_GRAFANA_TOKEN, sent as Bearer). A `token` in the settings file is never used: a
+   * credential is the vault's, never a setting (hq issue 342). Throws when neither is configured — the
+   * module then contributes nothing rather than failing.
    */
   static fromEnv(env: NodeJS.ProcessEnv = process.env): GrafanaClient {
     const cfg = meshConfig(env.MESH_GRAFANA_CONFIG_FILE);
     const url = cfg.url ?? env.MESH_GRAFANA_URL ?? `http://127.0.0.1:${env.GRAFANA_PORT ?? "3000"}`;
-    const token = cfg.token ?? env.MESH_GRAFANA_TOKEN;
-    if (token) return new GrafanaClient(url, `Bearer ${token}`);
+    ignoreSecretSetting(cfg, "token");
     const password = cfg.password ?? env.MESH_GRAFANA_PASSWORD;
     if (password) {
       const user = cfg.user ?? env.MESH_GRAFANA_USER ?? "admin";
       return new GrafanaClient(url, `Basic ${Buffer.from(`${user}:${password}`).toString("base64")}`);
     }
+    const token = env.MESH_GRAFANA_TOKEN;
+    if (token) return new GrafanaClient(url, `Bearer ${token}`);
     throw new Error("no Grafana auth — set MESH_GRAFANA_TOKEN or MESH_GRAFANA_PASSWORD");
   }
 

modules/grafana/module.json

@@ -142,7 +142,7 @@
       "mode": "0600",
       "content": "{\n  \"user\": \"admin\",\n  \"password\": \"${secret:admin}\"\n}\n",
       "merge": "json",
-      "protected": ["password"]
+      "protected": ["password", "token"]
     }
   ],
   "requires": [

modules/grafana/test/secret-setting.test.ts

@@ -0,0 +1,40 @@
+// A password, a token or an API key is the vault's, never a setting (novox/hq issue 342): grafana logs in
+// with the vault's admin password, a `token` in the settings file is ignored, and that is said once, by the
+// key alone. The runtime config keeps both keys protected, so the controller refuses a layer setting either.
+
+import { test, mock } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, readFileSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+
+import { GrafanaClient } from "../dist/client.js";
+
+const SETTING = "one-a-setting-carried";
+const VAULT = "the-vault-made-this";
+
+test("the vault's admin password is used, a token setting is ignored and said once, without its value", () => {
+  const said: string[] = [];
+  const err = mock.method(console, "error", (...args: unknown[]) => { said.push(args.join(" ")); });
+  try {
+    const dir = mkdtempSync(join(tmpdir(), "grafana-342-"));
+    // What the runtime config holds once the vault filled it, with a token a layer carried beside it.
+    writeFileSync(join(dir, "config.json"), JSON.stringify({ user: "admin", password: VAULT, token: SETTING }));
+    const env = { MESH_GRAFANA_CONFIG_FILE: join(dir, "config.json") };
+    const basic = "Basic " + Buffer.from(`admin:${VAULT}`).toString("base64");
+    assert.equal((GrafanaClient.fromEnv(env) as any).authHeader, basic);
+    assert.equal((GrafanaClient.fromEnv(env) as any).authHeader, basic);
+    assert.deepEqual(said, ["the setting token is ignored: it comes from the vault"]);
+    assert.ok(!said.join("\n").includes(SETTING), "the setting's value is never said");
+  } finally {
+    err.mock.restore();
+  }
+});
+
+test("the runtime config keeps password and token protected", () => {
+  const manifest = JSON.parse(readFileSync(new URL("../module.json", import.meta.url), "utf8")) as {
+    resources: { id: string; protected?: string[] }[];
+  };
+  const runtime = manifest.resources.find((r) => r.id === "runtime-config");
+  assert.deepEqual(runtime?.protected, ["password", "token"]);
+});