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Q60: How Do You Test GraphQL APIs in Postman?

🧬Core Concept

How Do You Test GraphQL APIs in Postman?

Key Takeaways & Architecture Summary

✓Select GraphQL as the request body format inside the client.
✓Define structured GraphQL queries or mutations directly in the editor.
✓Send queries via POST to a single endpoint (/graphql) and assert schemas.

Direct Answer Summary

To test GraphQL APIs in Postman, you send an HTTP POST request to the central `/graphql` endpoint, selecting "GraphQL" as the body format. You define your query or mutation schema inside the editor, passing variables and verifying the response structures.

⚠️ Senior Engineering Warning (Red Flag)

Never think GraphQL APIs use distinct HTTP verbs like PUT or DELETE. GraphQL queries and mutations are always sent as HTTP POST requests to a single endpoint, relying on the query payload to define actions.

💡 STAR Architectural Explanation & Pro Tip

GraphQL returns a 200 OK status code even when internal queries encounter exceptions. Automated scripts must check the response body for the `errors` array to confirm success.

RestAssuredTest.java

Rest-Assured + Java

// Postman POST query payload representing GraphQL
// POST https://api.careerraah.com/graphql
query FetchJobProfile($jobId: ID!) {
  job(id: $jobId) {
    title
    company
    status
  }
}