hicaosen/HTTP Assertion Patterns

HTTP Assertion Patterns for Postman Test Scripts

Provide assertion templates for verifying HTTP responses in Postman test scripts.

Pre-Request: Record Timestamp

Always record request start time for downstream trace/log queries:

pm.environment.set('requestStartTime', new Date().toISOString());
pm.environment.set('traceStartUs', Date.now() * 1000);

Core Assertion Patterns

Status Code

pm.test('[HTTP] Status is 200', function () {
    pm.response.to.have.status(200);
});

Response Body

var json = pm.response.json();
pm.test('[HTTP] Has required fields', function () {
    pm.expect(json).to.have.property('id');
    pm.expect(json.name).to.eql('expected value');
});

Array Response

pm.test('[HTTP] Response is non-empty array', function () {
    var json = pm.response.json();
    pm.expect(json).to.be.an('array').that.is.not.empty;
});

Response Headers

pm.test('[HTTP] Content-Type is JSON', function () {
    pm.expect(pm.response.headers.get('Content-Type')).to.include('application/json');
});

Variable Extraction

Extract values for downstream requests after assertions pass:

var json = pm.response.json();
pm.environment.set('createdId', json.id);
pm.environment.set('token', json.accessToken);

Standard HTTP Test Block

Use [HTTP] prefix in test names for consistent identification across three-layer output:

// 1. Status
pm.test('[HTTP] Status is 200', function () {
    pm.response.to.have.status(200);
});

// 2. Body structure
var json = pm.response.json();
pm.test('[HTTP] Has required fields', function () {
    pm.expect(json).to.have.property('id');
    pm.expect(json).to.have.property('name');
});

// 3. Extract for downstream
pm.environment.set('resourceId', json.id);

Naming Convention

Prefix all HTTP assertions with [HTTP] to distinguish from [TRACE] and [LOG] layers in test output.

Reference Files

For comprehensive assertion templates, consult:

• references/assertion-patterns.md — Complete patterns including schema validation, array checks, header assertions, pre-request scripts, and composite test blocks