8 months ago
I've a backend service (fastAPI) that I've verified is up and running.INFO: Started server process [1]
INFO: Waiting for application startup.
INFO: Application startup complete.
INFO: Uvicorn running on http://0.0.0.0:8000 (Press CTRL+C to quit)
From my frontend (next.js), I would like to call this API. However, I'm getting this error:Starting optimization process with http://label-hpo.railway.internal:8000/optimize
Error starting optimization: TypeError: fetch failed
at node:internal/deps/undici/undici:12618:11
at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
at async l (/app/.next/server/app/api/optimize/route.js:1:1167)
at async /app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/compiled/next-server/app-route.runtime.prod.js:6:36938
at async eC.execute (/app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/compiled/next-server/app-route.runtime.prod.js:6:27552)
at async eC.handle (/app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/compiled/next-server/app-route.runtime.prod.js:6:38272)
at async doRender (/app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/server/base-server.js:1345:42)
at async cacheEntry.responseCache.get.routeKind (/app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/server/base-server.js:1567:28)
at async NextNodeServer.renderToResponseWithComponentsImpl (/app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/server/base-server.js:1475:28)
at async NextNodeServer.renderPageComponent (/app/node_modules/.pnpm/next@14.2.13_@opentelemetry+api@1.9.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/next/dist/server/base-server.js:1901:24) {
cause: Error: connect ECONNREFUSED fd12:cf85:406c::e5:807b:e99b:8000
at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1555:16)
at TCPConnectWrap.callbackTrampoline (node:internal/async_hooks:128:17) {
errno: -111,
code: 'ECONNREFUSED',
syscall: 'connect',
address: 'fd12:cf85:406c::e5:807b:e99b',
port: 8000
}
}
A few things I've tried:
- Confirmed that the fastAPI app can connect to frontend on local when calling http://localhost:8000
- Tried calling by backend via label-hpo.railway.internal and label-hpo
What should I do to enable the connection between these two services in the same project?
2 Replies
8 months ago
Your fastapi app needs to listen on IPv6 since the private network is IPv6 only, this is done by binding to ::
Please note that uvicorn doesn't support dual stack binding (IPv6 & IPv4) so while binding to :: will allow it to work across the private network, you will lose the ability to access it publicly, if you need both, please use hypercorn instead.
Status changed to Solved brody • 8 months ago