API Testing,
Engineered.

const override = {
  expectedStatus: 200,

  // Every item in data.items must satisfy all rules
  assertEach: {
    path: "data.items", minCount: 1, maxCount: 100,
    rules: {
      "id":       { type: "number", gt: 0 },
      "name":     { type: "string", minLen: 1 },
      "price":    { type: "number", gte: 0 },
      "category": { type: "string" },
      "active":   { eq: true, soft: true }, // warn only
    }
  },

  // All IDs must be unique
  assertUnique: { path: "data.items", by: "id" },

  // Items sorted by price ascending
  assertOrder: {
    path: "data.items", by: "price",
    direction: "asc", type: "number"
  },
};

// pre-request.js
const override = {
  auth: {
    enabled: true, type: "oauth2cc",
    oauth2cc: {
      tokenUrl:     "https://auth.example.com/token",
      clientId:     "{{oauth_client_id}}",
      clientSecret: "{{oauth_client_secret}}",
      scope:        "orders:write",
    }
  },
  envRequired: ["oauth_client_id", "oauth_client_secret"],
};

// post-request.js
const override = {
  expectedStatus: 201,
  retryOnStatus: { statuses: [503, 429], maxRetries: 3 },
  assertShape: {
    "order.id":     "number",
    "order.status": "string",
    "error":        "absent",
  },
  varsToSave: {
    orderId: { path: "order.id", scope: "collection", name: "lastOrderId" }
  }
};

// pre-request.js — auto-generate pm.variables
const override = {
  randomData: {
    "email":   "random.email",       // → {{email}}
    "userId":  "random.int:1:9999",  // → {{userId}}
    "orderId": "random.uuid",        // → {{orderId}}
  },
};

// OR: newman run -d users.csv — iteration data
// Use {{iter.email}}, {{iter.name}} in URL / Body
// Access in scripts:  ctx.iteration.data.email

// post-request.js — conditional assertion
const override = {
  assertions: {
    "data.token": {
      exists: true,
      when: "ctx.response.code === 200"
    },
  },
  logLevel: "minimal", // one line per request
};

# .github/workflows/api-tests.yml
name: API Tests
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: npm install -g newman
      - run: |
          newman run collection.json \
            -e environments/prod.json \
            --reporter-json-export results.json
      - run: node scripts/summary.js results.json
      - run: node scripts/ci-to-junit.js results.json junit.xml
      - run: |
          # Detect regressions vs last baseline
          node scripts/compare.js baseline.json results.json