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BeginnerManual testing

API Testing for Manual QA

A practical course for manual testers who want to understand frontend and backend communication. Learn to read API contracts, design tests, use API tools, and investigate multiple API styles.

HTTP and RESTcurl and PostmanSwagger and OpenAPIAPI test designJSON and XMLSOAP, GraphQL and gRPCWebSocket testing
Learning outcomes

What you’ll be able to do.

01

Explain frontend, backend, client, server, API, and HTTP in plain words

02

Send authenticated REST and SOAP requests and interpret their responses

03

Design risk-based positive, negative, boundary, authorization, workflow, and retry tests

04

Use curl, Postman, Swagger, and protocol-specific tools to preserve reproducible evidence

05

Recognize GraphQL, gRPC, and WebSocket contracts and choose appropriate manual checks

Curriculum

12 focused modules.

48 lessons total
01Why API testing matters and what this course will teach youUnderstand why API testing matters in QA work. Preview the knowledge, practical skills, and outcomes that you will build.
  1. ↳Frontend, backend, and the journey of a clickLesson
  2. ↳What an API is and why teams use oneLesson
  3. ↳Clients, servers, and environmentsLesson
  4. ↳Your first API risk mapLesson
02HTTP without mysteryLearn the common language used by browsers and REST APIs.
  1. ↳URLs, paths, query parameters, and headersLesson
  2. ↳Requests, responses, and status codesLesson
  3. ↳GET, HEAD, and safe readingLesson
  4. ↳POST, PUT, PATCH, DELETE, and stateLesson
03Reading API dataBecome comfortable with the formats and contracts behind an API.
  1. ↳JSON: objects, arrays, values, and nullsLesson
  2. ↳Headers, content types, and negotiationLesson
  3. ↳Contracts, schemas, and breaking changesLesson
  4. ↳OpenAPI and Swagger as a mapLesson
04REST in practiceApply REST ideas without treating them as rigid magic.
  1. ↳Resources, representations, and RESTLesson
  2. ↳Filtering, sorting, search, and paginationLesson
  3. ↳Creating orders and Location headersLesson
  4. ↳Updates, deletes, and idempotencyLesson
05Tools a manual tester can trustUse approachable tools and preserve evidence others can reproduce.
  1. ↳curl: the small portable requestLesson
  2. ↳Postman: workspaces, collections, and variablesLesson
  3. ↳Importing OpenAPI and copying curlLesson
  4. ↳Evidence, logs, and a reproducible API bugLesson
06Authentication and security thinkingTest identity and access without turning the course into a security certification.
  1. ↳Authentication, authorization, and identityLesson
  2. ↳Bearer tokens, API keys, cookies, and Basic authLesson
  3. ↳Roles, ownership, and object-level accessLesson
  4. ↳Safe security tests for manual QALesson
07Designing strong API testsMove from endpoint checking to risk-based, connected test coverage.
  1. ↳Happy paths, rules, and boundariesLesson
  2. ↳Negative testing and error contractsLesson
  3. ↳State transitions and workflow testingLesson
  4. ↳Data integrity, concurrency, and retriesLesson
08The live REST challengeUse the qa.cafe temporary API to perform a complete exploratory session.
  1. ↳Start a private practice sessionLesson
  2. ↳Explore products and find contract gapsLesson
  3. ↳Build an order lifecycleLesson
  4. ↳Hunt the deliberate REST defectsLesson
09SOAP and XMLUnderstand an older but important enterprise API style.
  1. ↳XML: elements, attributes, namespaces, and validationLesson
  2. ↳SOAP envelopes, operations, and faultsLesson
  3. ↳WSDL and contract-first servicesLesson
  4. ↳Test the practice order SOAP serviceLesson
10GraphQLLearn how one endpoint can serve many query shapes.
  1. ↳GraphQL schema, queries, and fieldsLesson
  2. ↳Variables, mutations, and nested dataLesson
  3. ↳GraphQL errors, nullability, and partial successLesson
  4. ↳A GraphQL manual test charterLesson
11gRPCRecognize fast strongly typed service-to-service communication.
  1. ↳Protocol Buffers: messages, services, and methodsLesson
  2. ↳Unary and streaming RPCsLesson
  3. ↳gRPC status, metadata, and deadlinesLesson
  4. ↳Testing gRPC with grpcurl and GUI toolsLesson
12WebSockets and the final investigationTest long-lived communication and combine everything in a realistic capstone.
  1. ↳HTTP upgrade, connections, frames, and eventsLesson
  2. ↳WebSocket auth, reconnect, ordering, and heartbeatsLesson
  3. ↳Observe live order eventsLesson
  4. ↳Capstone: plan, execute, report, and reflectLesson
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