jackett: its config dir is placed, and its tools find their own key

The manifest named /services/jackett/config and /var/lib/mesh/jackett/config.json — host
paths ADR 0112 takes out of definitions. The config dir is now a pathless directory
(${dir:config}) and the runtime's config and route binding live in a placed state dir, as
searxng does.

The image is pinned to v0.24.2627-ls34, the digest ace runs today; the old pin
(v0.24.2517-ls16) was older than the running version.

The runtime reached jackett at a fixed 127.0.0.1:9117; it now uses ${port:9117}, the
machine port the mesh actually assigned.

The tools never loaded: the client needed an API key nobody set. Like sonarr/radarr read
config.xml, it now reads APIKey from Jackett's own ServerConfig.json (the config dir is
already mounted read-only), so no secret goes into an assignment. jackett_indexers called
/api/v2.0/indexers, which is the web UI's endpoint and answers an API key with a redirect;
it now reads the Torznab t=indexers feed, and treats Torznab's 200-with-<error> as a
failure.

Verified: catalogue key tests (MESH_CATALOGUE set, not skipped); a throwaway container of
the pinned image on a fresh 0700 1000:1000 config dir serves its UI; the client discovers
the key from the generated ServerConfig.json, lists 617 indexers through the Torznab feed,
searches via /results, and a wrong key is refused; client.ts typechecks under --strict.

modules/jackett/client.ts

@@ -2,7 +2,8 @@
 // an indexer proxy: it normalises many torrent trackers behind one Torznab surface. This client
 // talks its /api/v2.0 REST API, and only jackett's tools import it.
 
-import { readFileSync } from "node:fs";
+import { existsSync, readFileSync } from "node:fs";
+import { join } from "node:path";
 
 export interface JackettIndexer {
   id: string;
@@ -43,18 +44,36 @@ export class JackettClient {
 
   /**
    * Build from the module's resolved environment. Jackett's REST API is keyed, so both the URL and
-   * the key must be present — without them there is nothing to talk to, so this throws and the
-   * module contributes no tools rather than failing half-configured.
+   * the key must be present. The key is read from the settings-merged config or MESH_JACKETT_API_KEY,
+   * or, failing those, discovered from Jackett's own ServerConfig.json under MESH_JACKETT_CONFIG_DIR
+   * — the file Jackett writes it to, as sonarr/radarr read theirs from config.xml — so a running
+   * server needs no key configured by hand and no secret has to be put in an assignment. Without a
+   * URL or key there is nothing to talk to, so this throws and the module contributes no tools
+   * rather than failing half-configured.
    */
   static fromEnv(env: NodeJS.ProcessEnv = process.env): JackettClient {
     const cfg = meshConfig(env.MESH_JACKETT_CONFIG_FILE);
     const url = cfg.url ?? env.MESH_JACKETT_URL;
-    const apiKey = cfg.apiKey ?? env.MESH_JACKETT_API_KEY;
+    const apiKey = cfg.apiKey ?? env.MESH_JACKETT_API_KEY
+      ?? JackettClient.detectApiKey(env.MESH_JACKETT_CONFIG_DIR ?? "/config");
     if (!url) throw new Error("no Jackett URL — set MESH_JACKETT_URL");
-    if (!apiKey) throw new Error("no Jackett API key — set MESH_JACKETT_API_KEY");
+    if (!apiKey) throw new Error("no Jackett API key — set MESH_JACKETT_API_KEY or make the config dir readable");
     return new JackettClient(url, apiKey);
   }
 
+  /** Discover the API key from Jackett's ServerConfig.json (the linuxserver image keeps it at
+   *  <config>/Jackett/ServerConfig.json), falling back to null. */
+  static detectApiKey(configDir: string): string | null {
+    for (const file of [join(configDir, "Jackett", "ServerConfig.json"), join(configDir, "ServerConfig.json")]) {
+      if (!existsSync(file)) continue;
+      try {
+        const key = (JSON.parse(readFileSync(file, "utf8")) as { APIKey?: unknown }).APIKey;
+        if (typeof key === "string" && key) return key;
+      } catch { /* unreadable or mid-write: try the next, then give up */ }
+    }
+    return null;
+  }
+
   private async get(path: string, params: Record<string, string> = {}): Promise<any> {
     const url = new URL(`${this.baseUrl}${path}`);
     url.searchParams.set("apikey", this.apiKey);
@@ -64,18 +83,36 @@ export class JackettClient {
     return res.json();
   }
 
-  /** The configured indexers Jackett proxies. `configured=false` also lists the ones not set up. */
+  /**
+   * The configured indexers Jackett proxies. `configured=false` also lists the ones not set up.
+   * Read from the Torznab `t=indexers` feed, not /api/v2.0/indexers: that one is the web UI's and
+   * wants a login cookie (it answers an API-key request with a redirect), while the Torznab feed is
+   * what the key is for. The feed carries no last error, so `lastError` stays unset.
+   */
   async getIndexers(configuredOnly = true): Promise<JackettIndexer[]> {
-    const raw = await this.get("/api/v2.0/indexers", { configured: configuredOnly ? "true" : "false" });
-    const list = Array.isArray(raw) ? raw : [];
-    return list.map((i: any) => ({
-      id: i.id,
-      name: i.name,
-      type: i.type,
-      configured: i.configured ?? false,
-      siteLink: i.site_link,
-      lastError: i.last_error || undefined,
-    }));
+    const url = new URL(`${this.baseUrl}/api/v2.0/indexers/all/results/torznab/api`);
+    url.searchParams.set("apikey", this.apiKey);
+    url.searchParams.set("t", "indexers");
+    url.searchParams.set("configured", configuredOnly ? "true" : "false");
+    const res = await fetch(url.toString(), { headers: { Accept: "application/xml" } });
+    if (!res.ok) throw new Error(`Jackett API torznab t=indexers: ${res.status} ${await res.text()}`);
+    const xml = await res.text();
+    // Torznab reports failures (a wrong key among them) as 200 with an <error> body.
+    const err = xml.match(/<error code="(\d+)" description="([^"]*)"/);
+    if (err) throw new Error(`Jackett API torznab t=indexers: error ${err[1]} ${err[2]}`);
+    const text = (block: string, tag: string) =>
+      block.match(new RegExp(`<${tag}>([^<]*)</${tag}>`))?.[1];
+    const out: JackettIndexer[] = [];
+    for (const m of xml.matchAll(/<indexer id="([^"]+)" configured="([^"]+)">([\s\S]*?)<\/indexer>/g)) {
+      out.push({
+        id: m[1],
+        name: text(m[3], "title") ?? m[1],
+        type: text(m[3], "type") ?? "unknown",
+        configured: m[2] === "true",
+        siteLink: text(m[3], "link"),
+      });
+    }
+    return out;
   }
 
   /**

modules/jackett/module.json

@@ -10,7 +10,7 @@
       "port": 9117,
       "protocol": "tcp",
       "from": "mesh",
-      "why": "the indexer proxy"
+      "why": "the indexer proxy: its web UI, and the Torznab feeds the *arr apps search through"
     }
   ],
   "resources": [
@@ -20,10 +20,15 @@
       "path": "/var/lib/mesh/jackett",
       "mode": "0700"
     },
+    {
+      "id": "state",
+      "type": "directory",
+      "mode": "0700",
+      "place": "."
+    },
     {
       "id": "config",
       "type": "directory",
-      "path": "/services/jackett/config",
       "mode": "0700",
       "owner": "1000:1000"
     },
@@ -31,7 +36,7 @@
       "id": "server",
       "type": "container",
       "name": "jackett",
-      "image": "lscr.io/linuxserver/jackett@sha256:fd72d42b731ebf750b5de9711127251cf3b3f609419c32083ea8b3b3ee840b77",
+      "image": "lscr.io/linuxserver/jackett@sha256:7b19f4f6ac33d855ca9226600ecbd096ee678f66da28b13a7c09980b035ff583",
       "env": {
         "PUID": "1000",
         "PGID": "1000",
@@ -41,13 +46,13 @@
         "9117"
       ],
       "volumes": [
-        "/services/jackett/config:/config"
+        "${dir:config}:/config"
       ]
     },
     {
       "id": "runtime-config",
       "type": "file",
-      "path": "/var/lib/mesh/jackett/config.json",
+      "path": "${dir:state}/config.json",
       "mode": "0600",
       "content": "{}\n",
       "merge": "json"
@@ -59,12 +64,12 @@
       "network": "host",
       "volumes": [
         "/var/lib/mesh/jackett/broker:/run/secrets/broker:ro",
-        "/var/lib/mesh/jackett/config.json:/run/config/config.json:ro",
-        "/services/jackett/config:/var/lib/jackett/config:ro"
+        "${dir:state}/config.json:/run/config/config.json:ro",
+        "${dir:config}:/var/lib/jackett/config:ro"
       ],
       "env": {
         "MESH_BROKER_FILE": "/run/secrets/broker",
-        "MESH_JACKETT_URL": "http://127.0.0.1:9117",
+        "MESH_JACKETT_URL": "http://127.0.0.1:${port:9117}",
         "MESH_JACKETT_CONFIG_FILE": "/run/config/config.json",
         "MESH_JACKETT_CONFIG_DIR": "/var/lib/jackett/config"
       },
@@ -87,7 +92,7 @@
     }
   },
   "binds": {
-    "route": "/var/lib/mesh/jackett/route.json"
+    "route": "${dir:state}/route.json"
   },
   "build": {
     "on": [

modules/jackett/tools/index.ts

@@ -9,7 +9,7 @@ export function getJackettTools(jackett: JackettClient): ToolDefinition[] {
   return [
     {
       name: "jackett_indexers",
-      description: "List the indexers Jackett proxies, with their type and any last error.",
+      description: "List the indexers Jackett proxies, with their type and site.",
       input: { all: { type: "boolean", description: "include indexers not yet configured (default false)" } },
       run: async (args) => {
         const indexers = await jackett.getIndexers(!args.all);