| 25 | |
| 26 | // Mock BlockRun API server |
| 27 | async function startMockServer(): Promise<{ port: number; close: () => Promise<void> }> { |
| 28 | const server = createServer(async (req: IncomingMessage, res: ServerResponse) => { |
| 29 | const chunks: Buffer[] = []; |
| 30 | for await (const chunk of req) { |
| 31 | chunks.push(Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk)); |
| 32 | } |
| 33 | const body = Buffer.concat(chunks).toString(); |
| 34 | |
| 35 | try { |
| 36 | const parsed = JSON.parse(body) as { model?: string; messages?: Array<{ content: string }> }; |
| 37 | const model = parsed.model || "unknown"; |
| 38 | modelCalls.push(model); |
| 39 | |
| 40 | console.log(` [MockAPI] Request for model: ${model}`); |
| 41 | |
| 42 | // Simulate a slow model (per-model timeout test) |
| 43 | if (slowModels.includes(model) && slowModelDelayMs > 0) { |
| 44 | await new Promise((resolve) => setTimeout(resolve, slowModelDelayMs)); |
| 45 | } |
| 46 | |
| 47 | // Simulate 429 rate-limit on first call, succeed on retry (stepped backoff test) |
| 48 | if (rateLimitOnceModels.has(model)) { |
| 49 | const attempts = rateLimitAttempts.get(model) ?? 0; |
| 50 | rateLimitAttempts.set(model, attempts + 1); |
| 51 | if (attempts === 0) { |
| 52 | res.writeHead(429, { "Content-Type": "application/json" }); |
| 53 | res.end( |
| 54 | JSON.stringify({ |
| 55 | error: { message: "Rate limit exceeded", type: "rate_limited" }, |
| 56 | }), |
| 57 | ); |
| 58 | return; |
| 59 | } |
| 60 | // Second call succeeds — fall through to normal success path |
| 61 | } |
| 62 | |
| 63 | // Simulate an invalid explicit model name that should be surfaced to the caller |
| 64 | // instead of being silently converted into a free-model success. |
| 65 | if (model.startsWith("invalid/")) { |
| 66 | res.writeHead(400, { "Content-Type": "application/json" }); |
| 67 | res.end( |
| 68 | JSON.stringify({ |
| 69 | error: { |
| 70 | message: `Unknown model: ${model}. Available models: moonshot/kimi-k2.6, moonshot/kimi-k2.5, nvidia/gpt-oss-120b`, |
| 71 | type: "provider_error", |
| 72 | }, |
| 73 | }), |
| 74 | ); |
| 75 | return; |
| 76 | } |
| 77 | |
| 78 | // Simulate provider error for models in failModels list (or all models) |
| 79 | if (failAllModels || failModels.includes(model)) { |
| 80 | console.log(` [MockAPI] Simulating billing error for ${model}`); |
| 81 | res.writeHead(400, { "Content-Type": "application/json" }); |
| 82 | res.end( |
| 83 | JSON.stringify({ |
| 84 | error: { |