supplier+deploy/mainnet: optional OPENAI_API_KEY for DeepSeek (and other hosted OpenAI-compatible APIs)

Adds an optional OPENAI_API_KEY env var that supplier/src/openai.ts forwards as
`Authorization: Bearer <key>`. Empty/unset preserves the ChatMock behaviour
(no auth header). Unlocks pointing the openai backend at DeepSeek directly
(https://api.deepseek.com) — no local proxy needed.

New compose: deploy/mainnet/docker-compose.supplier-deepseek.yml (third mainnet
supplier, model deepseek-v4-pro, mp-suppliers-deepseek.vector.apexfusion.org).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

supplier/.env.example

@@ -42,6 +42,20 @@ PORT=8080
 # generous. Increase if you see ollama_timeout reasons in logs.
 OLLAMA_TIMEOUT_MS=120000
 
+# ─── Optional — OpenAI-compatible backend (LLM_BACKEND=openai) ────────────
+# Switch the chat job runner to POST /v1/chat/completions at OPENAI_BASE_URL
+# instead of Ollama. Used by the mainnet ChatMock-backed supplier and any
+# hosted OpenAI-compatible API (OpenAI, DeepSeek, etc.).
+# LLM_BACKEND=openai
+# OPENAI_BASE_URL=http://marketplace-mainnet-chatmock:8000  # or https://api.deepseek.com
+# OPENAI_TIMEOUT_MS=180000
+
+# OPENAI_API_KEY — optional bearer token. When set, the supplier forwards it
+# as `Authorization: Bearer <key>` on every /v1/chat/completions request.
+# Leave empty for endpoints that don't require auth (ChatMock, other local
+# proxies). REQUIRED for hosted APIs (DeepSeek, OpenAI). SECRET.
+# OPENAI_API_KEY=
+
 # ─── Optional (not in supplier/src/config.ts; consumed by index.ts boot) ──
 # Pre-derived public-key + pkh + bech32 address. M1-D will derive these from
 # SUPPLIER_PRIV_KEY_HEX automatically; until then index.ts reads them from

supplier/src/config.ts

@@ -65,6 +65,12 @@ export interface SupplierConfig {
   ollamaUrl: string;
   /** Empty string when capabilityKind="tts" or llmBackend="ollama". */
   openaiBaseUrl: string;
+  /**
+   * Bearer token forwarded as `Authorization: Bearer <key>` when llmBackend="openai".
+   * Empty string means no header is sent (correct for ChatMock and other localhost
+   * proxies). Required for hosted OpenAI-compatible APIs (DeepSeek, OpenAI, etc.).
+   */
+  openaiApiKey: string;
   /** Empty string when capabilityKind="chat". */
   piperUrl: string;
   advertRef: AdvertRef;
@@ -193,6 +199,8 @@ export function loadConfig(env: Record<string, string | undefined>): SupplierCon
     openaiTimeoutMs = Number(openaiTimeoutStr);
   }
 
+  const openaiApiKey = env.OPENAI_API_KEY ?? "";
+
   const piperTimeoutStr = env.PIPER_TIMEOUT_MS;
   let piperTimeoutMs = 120_000;
   if (piperTimeoutStr !== undefined && piperTimeoutStr !== "") {
@@ -212,6 +220,7 @@ export function loadConfig(env: Record<string, string | undefined>): SupplierCon
     ogmiosUrl,
     ollamaUrl,
     openaiBaseUrl,
+    openaiApiKey,
     piperUrl,
     advertRef,
     networkId,

supplier/src/jobRunner.ts

@@ -91,6 +91,7 @@ export async function runChatJob(params: RunChatJobParams): Promise<void> {
           model: advert.model,
           messages: requestBody.messages,
           timeoutMs: deps.config.openaiTimeoutMs,
+          apiKey: deps.config.openaiApiKey,
         });
       } else {
         inference = await ollama.callOllama({

supplier/src/openai.ts

@@ -33,6 +33,12 @@ export interface CallOpenAiParams {
   model: string;
   messages: ChatMessage[];
   timeoutMs: number;
+  /**
+   * Optional bearer token. When non-empty, an `authorization: Bearer <apiKey>`
+   * header is sent. Omit (or pass "") for endpoints that don't require auth,
+   * e.g. the ChatMock localhost proxy.
+   */
+  apiKey?: string;
 }
 
 export interface OpenAiResult {
@@ -62,10 +68,15 @@ function isAbortError(err: unknown): boolean {
 }
 
 export async function callOpenAi(params: CallOpenAiParams): Promise<OpenAiResult> {
-  const { baseUrl, model, messages, timeoutMs } = params;
+  const { baseUrl, model, messages, timeoutMs, apiKey } = params;
   const url = `${baseUrl}/v1/chat/completions`;
   const body = JSON.stringify({ model, messages, stream: false });
 
+  const headers: Record<string, string> = { "content-type": "application/json" };
+  if (apiKey) {
+    headers.authorization = `Bearer ${apiKey}`;
+  }
+
   const controller = new AbortController();
   const timer = setTimeout(() => controller.abort(), timeoutMs);
 
@@ -74,7 +85,7 @@ export async function callOpenAi(params: CallOpenAiParams): Promise<OpenAiResult
   try {
     response = await fetch(url, {
       method: "POST",
-      headers: { "content-type": "application/json" },
+      headers,
       body,
       signal: controller.signal,
     });