Postman

Build, test, and automate APIs with Postman collections, environments, and Newman CLI.

Setup

If ~/postman/ doesn't exist, read setup.md silently and start naturally.

When to Use

User needs to test APIs, create Postman collections, manage environments, or run automated API tests with Newman.

Architecture

Data lives in ~/postman/. See memory-template.md for structure.

text

~/postman/
├── memory.md           # Projects, preferences, common patterns
├── collections/        # Postman collection JSON files
└── environments/       # Environment JSON files

Quick Reference

Topic	File
Setup	setup.md
Memory template	memory-template.md
Collection format	collections.md
Newman automation	newman.md

Core Rules

1. Collection Structure First

Before creating requests, define the collection structure:

• Folder hierarchy reflects API organization
• Use descriptive names: Users > Create User, not POST 1
• Group related endpoints logically

2. Environment Variables Always

Never hardcode values that change between environments:

json

{
  "key": "base_url",
  "value": "https://api.example.com",
  "enabled": true
}

Use {{base_url}} in requests. Environments: dev, staging, prod.

3. Pre-request Scripts for Auth

Handle authentication in pre-request scripts, not manually:

javascript

// Get token and set for collection
pm.sendRequest({
    url: pm.environment.get("auth_url"),
    method: 'POST',
    body: { mode: 'raw', raw: JSON.stringify({...}) }
}, (err, res) => {
    pm.environment.set("token", res.json().access_token);
});

4. Test Assertions Required

Every request needs at least basic assertions:

javascript

pm.test("Status 200", () => pm.response.to.have.status(200));
pm.test("Has data", () => pm.expect(pm.response.json()).to.have.property("data"));

5. Newman for CI/CD

Run collections headlessly with Newman:

bash

newman run collection.json -e environment.json --reporters cli,json

Exit code 0 = all tests passed. Integrate into CI pipelines.

Collection Format

Minimal Collection

json

{
  "info": {
    "name": "My API",
    "schema": "https://schema.getpostman.com/json/collection/v2.1.0/collection.json"
  },
  "item": [
    {
      "name": "Get Users",
      "request": {
        "method": "GET",
        "url": "{{base_url}}/users",
        "header": [
          { "key": "Authorization", "value": "Bearer {{token}}" }
        ]
      }
    }
  ]
}

With Tests

json

{
  "name": "Create User",
  "request": {
    "method": "POST",
    "url": "{{base_url}}/users",
    "body": {
      "mode": "raw",
      "raw": "{\"name\": \"{{$randomFullName}}\", \"email\": \"{{$randomEmail}}\"}",
      "options": { "raw": { "language": "json" } }
    }
  },
  "event": [
    {
      "listen": "test",
      "script": {
        "exec": [
          "pm.test('Created', () => pm.response.to.have.status(201));",
          "pm.test('Has ID', () => pm.expect(pm.response.json().id).to.exist);"
        ]
      }
    }
  ]
}

Environment Format

json

{
  "name": "Development",
  "values": [
    { "key": "base_url", "value": "http://localhost:3000", "enabled": true },
    { "key": "token", "value": "", "enabled": true }
  ]
}

Newman Commands

Task	Command
Basic run	newman run collection.json
With environment	newman run collection.json -e dev.json
Specific folder	newman run collection.json --folder "Users"
Iterations	newman run collection.json -n 10
Data file	newman run collection.json -d data.csv
HTML report	newman run collection.json -r htmlextra
Bail on fail	newman run collection.json --bail

Common Traps

• Hardcoded URLs → Tests break between environments. Always use {{base_url}}.
• No assertions → Tests "pass" but don't validate anything. Add status + body checks.
• Secrets in collection → Credentials leak. Use environment variables, gitignore env files.
• Sequential dependencies → Tests fail randomly. Use setNextRequest() explicitly or make tests independent.
• Missing Content-Type → POST/PUT fails silently. Always set Content-Type: application/json.

Dynamic Variables

Postman built-in variables for test data:

Variable	Example Output
{{$randomFullName}}	"Jane Doe"
{{$randomEmail}}	"[e-mail]"
{{$randomUUID}}	"550e8400-e29b-..."
{{$timestamp}}	1234567890
{{$randomInt}}	42

OpenAPI to Postman

Import OpenAPI/Swagger specs:

1. Export OpenAPI JSON/YAML
2. In Postman: Import > File > Select spec
3. Collection auto-generated with all endpoints

Or via CLI:

bash

npx openapi-to-postmanv2 -s openapi.yaml -o collection.json

Security & Privacy

Data that stays local:

• Collections and environments in ~/postman/
• Newman runs locally

This skill does NOT:

• Send collections to external services
• Store API credentials in memory.md

Related Skills

Install with clawhub install <slug> if user confirms:

• api — REST API consumption patterns
• json — JSON manipulation and validation
• ci-cd — Pipeline automation

Feedback

• If useful: clawhub star postman
• Stay updated: clawhub sync