Keep every password, token and API key the vault's, never a setting (hq issue 342)

A setting outranked the vault: baserow, grafana, letta and unifi merged a layer's
password over the ${secret:...} in their runtime config, and the gitea,
home-assistant, icecast, influxdb, mailu and nextcloud clients read the settings
file before the vault's file. A secret in a setting cannot be rotated and is read
back by the settings verb.

The four files now keep their password protected, so the controller refuses a
setting of it. The six clients ignore a secret in the settings file and say so
once, by key and never with the value; icecast reads its admin password from the
vault's file. checks/secrets refuses a mergeable file whose secret a layer could
replace; searxng's nested server.secret_key is listed as known until the
controller protects a nested key.

modules/gitea/client.ts

@@ -138,6 +138,17 @@ 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 ${key} is ignored: it comes from the vault`);
+}
+
 export class GiteaClient {
   readonly baseUrl: string;
   private readonly tokens: TokenSource;
@@ -151,7 +162,8 @@ export class GiteaClient {
   /**
    * Build from the module's resolved environment. The URL comes from MESH_GITEA_URL (the mesh's own
    * name), falling back to the bare GITEA_URL and to the forge's loopback port. The token, in order:
-   * one configured in settings or the environment (MESH_GITEA_TOKEN / GITEA_TOKEN), which wins; else
+   * one configured in the environment (MESH_GITEA_TOKEN / GITEA_TOKEN), which wins — never a setting, which is
+   * ignored and said (hq issue 342); else
    * one the module mints for itself with the admin account the vault delivered and keeps in its own
    * state (token.ts; hq issue 100). Throws only when neither is possible, naming what is missing,
    * rather than hand back a client that fails on first use.
@@ -159,7 +171,8 @@ export class GiteaClient {
   static fromEnv(env: NodeJS.ProcessEnv = process.env): GiteaClient {
     const cfg = meshConfig(env.MESH_GITEA_CONFIG_FILE);
     const url = cfg.url ?? env.MESH_GITEA_URL ?? env.GITEA_URL ?? `http://127.0.0.1:${env.GITEA_PORT ?? "3000"}`;
-    const configured = cfg.token ?? env.MESH_GITEA_TOKEN ?? env.GITEA_TOKEN;
+    ignoreSecretSetting(cfg, "token");
+    const configured = env.MESH_GITEA_TOKEN ?? env.GITEA_TOKEN;
     if (configured) return new GiteaClient(url, new ConfiguredToken(configured));
     return new GiteaClient(url, MintedToken.fromEnv(url, env));
   }

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

@@ -0,0 +1,41 @@
+// A password, a token or an API key is the vault's, never a setting (novox/hq issue 342): a value for it in
+// the settings file the mesh merges is ignored, the vault's is used, and that is said once, by the key alone.
+// Run against the compiled module, the way the runtime loads it.
+
+import { test, mock } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+
+import { GiteaClient } from "../dist/client.js";
+import { ConfiguredToken, MintedToken } from "../dist/token.js";
+
+const SETTING = "one-a-setting-carried";
+const VAULT = "the-vault-made-this";
+
+function delivered(settings: Record<string, string>): Record<string, string> {
+  const dir = mkdtempSync(join(tmpdir(), "gitea-342-"));
+  writeFileSync(join(dir, "config.json"), JSON.stringify(settings));
+  writeFileSync(join(dir, "vault.secret"), VAULT + "\n");
+  return { dir, config: join(dir, "config.json"), vault: join(dir, "vault.secret") };
+}
+
+test("the vault's token is used, a setting of it 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 at = delivered({ token: SETTING });
+    const env = { MESH_GITEA_CONFIG_FILE: at.config, MESH_GITEA_URL: "http://127.0.0.1:1", MESH_GITEA_ADMIN_USER: "mesh-admin", MESH_GITEA_ADMIN_PASSWORD_FILE: at.vault, MESH_GITEA_STATE_DIR: at.dir };
+    const first = GiteaClient.fromEnv(env);
+    const second = GiteaClient.fromEnv(env);
+    // No token from the setting: the module mints its own with the vault's admin account.
+    assert.ok((first as any).tokens instanceof MintedToken);
+    assert.ok((second as any).tokens instanceof MintedToken);
+    assert.ok(!((first as any).tokens instanceof ConfiguredToken));
+    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();
+  }
+});