GraphQL New Added 10 September 2026

Apollo Server: POST body missing, invalid Content-Type

Apollo Server 4 does not parse request bodies itself, so the Express integration needs express.json() mounted before it. The other half of the cases is a client or proxy that sends no content type header, since anything other than application/json or application/graphql-response+json is refused.

Quick fix

Read the commands before running them. Anything that restarts a service, deletes data or changes permissions should be tried on a non-production system first.

Quick fix

// Order matters: body parsing has to be mounted first
import express from "express";
import { expressMiddleware } from "@apollo/server/express4";

const app = express();
await server.start();
app.use("/graphql", express.json(), expressMiddleware(server));

# Reproduce it and look at the headers being sent
curl -i https://api.example.com/graphql \
  -H 'content-type: application/json' \
  -d '{"query":"{ __typename }"}'

# A 400 with this message and no content-type in the request means a proxy
# stripped it, or the client sent form data
curl -i -X POST https://api.example.com/graphql -d 'query={ __typename }'

// Health checks that POST an empty body will log this constantly:
// point them at a GET route instead

How to diagnose GraphQL errors

GraphQL returns HTTP 200 with an errors array far more often than it returns a non-2xx status, so clients that only check the status code silently ignore failures. Errors split into validation (the query does not match the schema, always fixable from the schema), authorisation (per-field resolvers rejecting), and performance guards (depth and complexity limits) which exist to protect the server from expensive queries.

If the quick fix above does not resolve it, work through these steps. They apply to this whole class of error, not just to this one message, which is usually what saves the time.

Always inspect the errors array, not just the HTTP status. Each entry carries a path that points at the exact field that failed.
Validate the query against the schema locally before sending it. GraphQL IDEs and graphql-codegen catch every validation error at build time.
For N+1 problems, enable resolver tracing or SQL logging and count queries per request. A DataLoader that batches by key is the standard fix.
When you hit a depth or complexity limit, restructure the query rather than raising the limit. The limit is usually protecting the database from an unbounded traversal.
Check whether the error is from the gateway or the subgraph in a federated setup; the two have separate schemas and separate authorisation.

Tools worth reaching for

GraphiQL / Apollo Sandbox
graphql-codegen
Apollo tracing
DataLoader

Authoritative references

Primary documentation for this error, worth reading before applying any fix in production.

apollographql.com

Related GraphQL errors

See all 13 GraphQL errors →

Browse other categories

Something missing or wrong?

This entry is maintained by hand. If the fix is out of date, incomplete, or you have a better one, email a correction and it will be reviewed.