From 14aed763559d0ae5037a8e265fac3e5e00ebedd5 Mon Sep 17 00:00:00 2001 From: Andrew Adel Date: Sat, 16 May 2026 19:35:47 +0300 Subject: [PATCH] Add cds-test-architect docs and license Introduce a new cds-test-architect skill under skills/cds-test-architect. Adds SKILL.md (guidance, setup, patterns, anti-patterns, and checklist for writing cds.test() unit/integration tests) and EXAMPLES.md (six runnable test templates: OData CRUD, custom actions, programmatic service, PATCH/DELETE, error responses, and log capture). Also adds an Apache-2.0 LICENSE file (copyright 2026 Andrew Saba). --- skills/cds-test-architect/EXAMPLES.md | 224 ++++++++++++++++++++++++++ skills/cds-test-architect/LICENSE | 201 +++++++++++++++++++++++ skills/cds-test-architect/SKILL.md | 183 +++++++++++++++++++++ 3 files changed, 608 insertions(+) create mode 100644 skills/cds-test-architect/EXAMPLES.md create mode 100644 skills/cds-test-architect/LICENSE create mode 100644 skills/cds-test-architect/SKILL.md diff --git a/skills/cds-test-architect/EXAMPLES.md b/skills/cds-test-architect/EXAMPLES.md new file mode 100644 index 00000000..175e33de --- /dev/null +++ b/skills/cds-test-architect/EXAMPLES.md @@ -0,0 +1,224 @@ +# Examples — CDS Backend Tests + +Six runnable templates. Adapt the entity, service, and field names; keep the structure. + +## 1. OData CRUD + +Happy-path read + create against `srv/services/pay/payroll-loans.cds`. Asserts the OData layer is wired and audit fields are populated by the service. + +```js +// test/pay/payroll-loans.test.js +const cds = require('@sap/cds') +const { GET, POST, expect, data } = cds.test(__dirname + '/../..') + +describe('PayrollLoans — OData CRUD', () => { + beforeEach(() => data.reset()) + + it('lists loans for an authenticated user', async () => { + const { data: body, status } = await GET('/odata/v4/payroll-loans/Loans', { + auth: { username: 'alice' }, + }) + expect(status).to.equal(200) + expect(body.value).to.be.an('array') // we don't pin row count — fixtures drift + }) + + it('creates a loan and stamps audit fields', async () => { + const { data: created, status } = await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-001', principal: 1000, currency: 'EGP' }, + { auth: { username: 'alice' } }, + ) + expect(status).to.equal(201) + // assert only what this test is about — the createdBy stamp + expect(created).to.containSubset({ createdBy: 'alice', principal: 1000 }) + }) +}) +``` + +## 2. Custom action + +Bound action with auth gating. Two users, one allowed, one denied — asserts the role check, not the action body. + +```js +// test/pay/payroll-cycle-approvals.test.js +const cds = require('@sap/cds') +const { POST, expect, data } = cds.test(__dirname + '/../..') + +describe('PayrollCycleApprovals — approveApproval action', () => { + beforeEach(() => data.reset()) + + it('admin can approve a pending approval', async () => { + const { status, data: body } = await POST( + `/odata/v4/payroll-cycle-approvals/Approvals()/PayrollCycleApprovalService.approveApproval`, + {}, + { auth: { username: 'alice' } }, + ) + expect(body).to.containSubset({ status: 'APPROVED' }) // payload first + expect(status).to.equal(200) // status second + }) + + it('viewer is rejected with 403', async () => { + const res = await POST( + `/odata/v4/payroll-cycle-approvals/Approvals()/PayrollCycleApprovalService.approveApproval`, + {}, + { auth: { username: 'bob' }, validateStatus: () => true }, // don't throw on 4xx + ) + expect(res.status).to.equal(403) + }) +}) +``` + +`validateStatus: () => true` is the escape hatch for asserting error responses — without it `cds.test` throws before the `expect` is reached. + +## 3. Programmatic service + +No HTTP — talk to the service through `cds.connect.to`. Best for verifying handler logic that has no external surface (e.g. an internal event handler). + +```js +// test/core/employee-records-service.test.js +const cds = require('@sap/cds') +const { expect, data } = cds.test(__dirname + '/../..') + +describe('EmployeeRecordsService — programmatic', () => { + let EmployeeRecords + beforeAll(async () => { // beforeAll, not before() — works across runners + EmployeeRecords = await cds.connect.to('EmployeeRecordsService') + }) + beforeEach(() => data.reset()) + + it('returns records keyed by personIdExternal, never userId', async () => { + const { Employees } = EmployeeRecords.entities + const rows = await SELECT.from(Employees).limit(1) + expect(rows[0]).to.have.property('personIdExternal') // SF PK rule from CLAUDE.md + expect(rows[0]).to.not.have.property('userId') // userId is audit-only + }) +}) +``` + +Programmatic tests skip the protocol layer, so they're faster and surface handler errors directly. Reach for them when the OData round-trip adds nothing to the assertion. + +## 4. PATCH and DELETE + +PATCH an entity and assert the `modifiedBy` stamp; DELETE and assert the record is gone. + +```js +// test/pay/payroll-loans.test.js (extend the same file as example 1) +const cds = require('@sap/cds') +const { GET, POST, PATCH, DELETE, expect, data } = cds.test(__dirname + '/../..') + +describe('PayrollLoans — updates and deletes', () => { + beforeEach(() => data.reset()) + + it('patches a loan principal and stamps modifiedBy', async () => { + // create first so we have a stable ID within this test + const { data: created } = await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-002', principal: 500, currency: 'EGP' }, + { auth: { username: 'alice' } }, + ) + const id = created.ID + + const { data: patched, status } = await PATCH( + `/odata/v4/payroll-loans/Loans(${id})`, + { principal: 750 }, + { auth: { username: 'alice' } }, + ) + expect(patched).to.containSubset({ principal: 750, modifiedBy: 'alice' }) + expect(status).to.equal(200) + }) + + it('deletes a loan and returns 204', async () => { + const { data: created } = await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-003', principal: 200, currency: 'EGP' }, + { auth: { username: 'alice' } }, + ) + const id = created.ID + + const { status } = await DELETE( + `/odata/v4/payroll-loans/Loans(${id})`, + { auth: { username: 'alice' } }, + ) + expect(status).to.equal(204) + + // confirm the record is gone + const { data: body } = await GET( + `/odata/v4/payroll-loans/Loans(${id})`, + { auth: { username: 'alice' }, validateStatus: () => true }, + ) + expect(body).to.containSubset({ error: { code: '404' } }) + }) +}) +``` + +## 5. Error response (4xx) + +Assert validation errors, business-rule rejections, and auth failures. Use `validateStatus: () => true` so `cds.test` does not throw. Assert `error.code`, not `error.message` — codes are stable contract; messages are translated. + +```js +// test/pay/payroll-loans.test.js +const cds = require('@sap/cds') +const { POST, expect, data } = cds.test(__dirname + '/../..') + +describe('PayrollLoans — validation errors', () => { + beforeEach(() => data.reset()) + + it('rejects a negative principal with 400 and a stable error code', async () => { + const res = await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-001', principal: -1, currency: 'EGP' }, + { auth: { username: 'alice' }, validateStatus: () => true }, + ) + // payload first — tells you *why* on failure + expect(res.data).to.containSubset({ error: { code: 'INVALID_PRINCIPAL' } }) + expect(res.status).to.equal(400) + }) + + it('rejects unauthenticated requests with 401', async () => { + const res = await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-001', principal: 100, currency: 'EGP' }, + { validateStatus: () => true }, // no auth + ) + expect(res.status).to.equal(401) + }) +}) +``` + +## 6. Log capture + +Assert that a handler emits specific warnings or info entries (via `req.warn`, `req.info`) without needing a separate DB assertion. Useful for verifying business rules that warn but do not reject. + +```js +// test/pay/payroll-loans.test.js +const cds = require('@sap/cds') +const { POST, expect, data } = cds.test(__dirname + '/../..') + +describe('PayrollLoans — ceiling warning', () => { + let log + beforeAll(() => { log = cds.test.log() }) + afterAll(() => log.release()) // restore normal output after the suite + beforeEach(() => { log.clear(); return data.reset() }) + + it('warns when loan principal exceeds the ceiling', async () => { + await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-001', principal: 999999, currency: 'EGP' }, + { auth: { username: 'alice' } }, + ) + // check log output contains the warning code emitted by the handler + expect(log.output).to.contain('CEILING_EXCEEDED') + }) + + it('does not warn for a normal loan', async () => { + await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-002', principal: 500, currency: 'EGP' }, + { auth: { username: 'alice' } }, + ) + expect(log.output).to.not.contain('CEILING_EXCEEDED') + }) +}) +``` + +`log.output` is a plain string of all stdout/stderr since the last `log.clear()`. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright 2026 Andrew Saba + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. diff --git a/skills/cds-test-architect/SKILL.md b/skills/cds-test-architect/SKILL.md new file mode 100644 index 00000000..bc008cf8 --- /dev/null +++ b/skills/cds-test-architect/SKILL.md @@ -0,0 +1,183 @@ +--- +name: cds-test-architect +description: Unit and integration testing for the CAP backend using cds.test() from Capire. Use when the user asks for backend tests, writes a *.test.js under test/, mentions cds.test, @cap-js/cds-test, supertest-style HTTP tests for OData/actions, or wants a regression test for a CAP handler, action, or payroll/core/platform service. +--- + +# Unit Testing the CDS Backend + +## When this fires + +Triggered for code under `srv/services/**` (pay, core, platform) and `srv/handlers/**`. **Not** for Playwright UI tests under `app-core/e2e/` or `app-pay/e2e/` — those have their own runners. Always co-locate backend tests under `test//.test.js`, mirroring `srv/services//.cds`. Tests must never live under `srv/` — that directory ships to deployments. + +## Philosophy + +Test through public interfaces — OData endpoints or `cds.connect.to()` — never by reaching into handler internals or stubbing `cds.db`. Capire's mantra applies: *"The more you mock, the less you test the real thing."* A test that breaks on a rename without behavior change is a bad test. + +Real Postgres, real `cds.test()` bootstrap, real handlers. Reset DB state between tests, don't fake it. + +## First-run setup (once per repo) + +Before adding the first test, run this checklist. Stop and ask the user before editing `package.json`. + +- [ ] Install the test helper: `npm i -D @cap-js/cds-test` +- [ ] Add to [package.json](../../../package.json) `scripts`: `"test": "cds test"` +- [ ] Add mocked users under `cds.requires.auth` (test + development profiles): + ```json + "auth": { + "[development]": { "kind": "mocked" }, + "[test]": { + "kind": "mocked", + "users": { + "alice": { "roles": ["admin", "payroll.approver"] }, + "bob": { "roles": ["viewer"] } + } + } + } + ``` +- [ ] Create `test/` at repo root (sibling of `srv/`, `db/`, `app-core/`). +- [ ] Confirm Postgres test DB is reachable on the active profile — the skill does **not** auto-configure a `pg-test` profile. +- [ ] Add `CDS_TEST_ENV_CHECK=y` to your test environment (`.env.test` or the `test` script in `package.json`). This causes `cds.test` to error if `cds.env` is accessed before `cds.test()` runs, which prevents plugins from loading from the wrong folder. + +## Canonical test file + +Every backend test file follows this shape: + +```js +const cds = require('@sap/cds') +const { GET, POST, expect, data } = cds.test(__dirname + '/../..') + +describe(' — ', () => { + beforeEach(() => data.reset()) + + it('lists for an authenticated user', async () => { + const { data: body, status } = await GET('/odata/v4//', { + auth: { username: 'alice' }, + }) + expect(status).to.equal(200) + expect(body.value).to.containSubset([{ /* essential fields only */ }]) + }) +}) +``` + +`cds.test()` is called **once at file scope** — never inside `describe` or `beforeAll`. The path argument anchors `cds.root` at the repo so the same `db/` and `srv/services/` are picked up. + +### Selective service boot + +When a test file covers exactly one service, pass the service name to avoid booting unrelated services and reduce startup time: + +```js +const { GET, POST, expect, data } = cds.test('serve', 'PayrollLoansService').in(__dirname + '/../..') +``` + +Use `.in()` fluently after the service name so `cds.root` is still anchored correctly. + +## File-wide defaults + +Use the `defaults` object to set auth, headers, or `validateStatus` once for the whole file instead of repeating them on every request. Per-request options override `defaults`. + +```js +const { GET, POST, expect, data, defaults } = cds.test(__dirname + '/../..') +defaults.auth = { username: 'alice' } // all requests run as alice unless overridden + +// override for the one test that needs a different user +const res = await GET('/odata/v4/payroll-loans/Loans', { auth: { username: 'bob' } }) +``` + +Supported `defaults` keys: `auth`, `headers`, `baseURL`, `validateStatus`. + +## Error responses (4xx / 5xx) + +`cds.test` throws by default when a response has a 4xx or 5xx status, so a bare `await POST(...)` will throw before you can assert the body. Use `validateStatus: () => true` to receive the error response instead of throwing: + +```js +const res = await POST( + '/odata/v4/payroll-loans/Loans', + { principal: -1 }, + { auth: { username: 'alice' }, validateStatus: () => true }, +) +// assert payload first — it tells you why the error happened +expect(res.data).to.containSubset({ error: { code: 'INVALID_PRINCIPAL' } }) +expect(res.status).to.equal(400) +``` + +Always assert `error.code`, never `error.message` — messages are translated and can change; codes are stable contract. + +## Log capture + +Use `cds.test.log()` to assert that handlers emit specific warnings or info messages (e.g. `req.warn`, `req.info`, structured audit entries) without writing a separate DB assertion. + +```js +describe('PayrollLoansService — ceiling warning', () => { + let log + beforeAll(() => { log = cds.test.log() }) + afterAll(() => log.release()) + beforeEach(() => { log.clear(); return data.reset() }) + + it('warns when loan exceeds ceiling', async () => { + await POST( + '/odata/v4/payroll-loans/Loans', + { personIdExternal: 'EXT-001', principal: 999999, currency: 'EGP' }, + { auth: { username: 'alice' } }, + ) + expect(log.output).to.contain('CEILING_EXCEEDED') + }) +}) +``` + +`log.output` is a plain string of everything written to stdout/stderr since the last `log.clear()`. `log.release()` stops capturing and restores normal output. + +## `data.reset()` semantics + +`data.reset()` drops and re-deploys the full database schema, then re-seeds from `db/data/` CSV fixtures. Every test therefore starts from a known, identical baseline. Call it in `beforeEach` — not `afterEach` — so failures leave the DB in the broken state for debugging. + +If a test creates records it needs to reference by ID (e.g. a seeded approval for an action test), seed those IDs in your CSV fixtures under `db/data/` rather than creating them inside the test — fixture IDs are stable across resets; `POST`-created IDs are not. + +## Test patterns + +| Pattern | When | Example | +| --- | --- | --- | +| OData CRUD (GET/POST) | Validating a service entity is reachable and obeys auth | See [EXAMPLES.md](EXAMPLES.md#1-odata-crud) | +| OData update/delete (PATCH/DELETE) | Testing write handlers, cascade deletes, optimistic lock | See [EXAMPLES.md](EXAMPLES.md#4-patch-and-delete) | +| Custom action | Testing bound/unbound actions like `approveApproval`, `runPayrollCycle` | See [EXAMPLES.md](EXAMPLES.md#2-custom-action) | +| Error response (4xx) | Asserting validation, auth rejection, or business-rule errors | See [EXAMPLES.md](EXAMPLES.md#5-error-response) | +| Programmatic service | Driving a service without HTTP — best for handler unit logic | See [EXAMPLES.md](EXAMPLES.md#3-programmatic-service) | +| Log capture | Asserting `req.warn` / `req.info` emitted by a handler | See [EXAMPLES.md](EXAMPLES.md#6-log-capture) | + +## Anti-patterns + +- **Do not** mock `cds.db`, `srv/handlers/**/lib/*`, the SF client, or `bullmq` queues. If you need to skip a side effect, use a feature flag in the handler, not a test mock. +- **Do not** call `cds.test()` more than once per file — it boots a server and leaks state. +- **Do not** use `process.chdir()`; if you need a different root, use `cds.test.in(__dirname)`. +- **Do not** use `deep.equal` on full responses — IDs and `createdAt`/`modifiedAt` will fight you. Use `containSubset` and assert only the fields the test is *about*. +- **Do not** assert HTTP status before payload — when a 500 comes back, the payload tells you why; the status alone hides the bug. +- **Do not** assert `error.message` — assert `error.code`. Messages are translated and unstable; codes are contract. +- **Do not** assert 4xx/5xx responses without `validateStatus: () => true` — `cds.test` throws on error responses by default, so the assertion is never reached. +- **Do not** use `personIdExternal` and `userId` interchangeably — per [CLAUDE.md](../../../CLAUDE.md), `personIdExternal` is the FK; `userId` is audit-only and unstable across rehires. +- **Do not** put tests under `srv/`, `db/`, or `app-*/`. +- **Do not** use `before()` (Mocha-only) — use `beforeAll()` which works across runners. + +## Checklist per test + +- [ ] File at `test//.test.js`, mirroring `srv/services//.cds` +- [ ] `cds.test()` called once at file scope +- [ ] `data.reset()` (or explicit fixture) in `beforeEach` +- [ ] Auth via `auth: { username }` against a user defined in the `[test]` mocked profile +- [ ] `validateStatus: () => true` on any request expected to return 4xx/5xx +- [ ] Asserts observable behavior — OData response, service API return value, or audit-log row — never handler internals +- [ ] Uses `containSubset`, not `deep.equal`, for response bodies +- [ ] Asserts `error.code`, not `error.message`, for error cases +- [ ] No mocks for `cds.db`, SF client, or queues + +## Verification + +`npm test` invokes `cds test`, which runs Node's built-in `--test`. The boot-time schema-drift warner in [srv/server.js](../../../srv/server.js) is gated on `NODE_ENV !== 'test'`, so test boots stay quiet. + +To smoke-test a new test file: + +``` +npm test -- test/pay/payroll-loans.test.js +``` + +If the test fails with `ECONNREFUSED` on Postgres, the test DB is not reachable — fix the profile, not the test. + +If the test fails with `cds.env loaded before cds.test()`, ensure `cds.test()` is the first `cds` call in the file and that no top-level module import triggers `cds.env` as a side effect.