write-e2e-cumulocity-cypress-test

Write and verify e2e Cypress tests for Cumulocity

You are writing deterministic Cypress test code (no cy.prompt()), validating it yourself in a loop until it passes. A test is not done until you have run it headlessly and seen it green.

Workflow at a glance:

1. Preflight — verify .env, dev server, tenant/base-URL match, device ID.
2. Discover — walk the flow in a live browser (selectors, requests, response shapes), then confirm the backend contract in the Angular service source.
3. Write — standard suite skeleton, intercept every relevant request before visiting, assert via stable selectors.
4. Verify — run headless in a loop, diagnose from the request trace, fix, repeat; full suite once when green.
5. Finish — delete run logs, report pass/fail counts, fold new lessons back into this skill.

This skill is project-agnostic. Placeholders in angle brackets (<feature>, <Tab label>, …) must be replaced with names discovered in the repo you are working in — never invent them.

Phase 0 — Preflight: verify the environment before writing anything

Run these checks first. Every minute spent here saves a failed-run iteration later.

1. Learn the project's env contract. Read cypress.config.ts (and cypress/support/e2e.ts) to see which .env/environment keys the project reads and how they map into Cypress. Typical keys: C8Y_TENANT, C8Y_BASEURL, C8Y_USERNAME, C8Y_PASSWORD, C8Y_SHELL_TARGET, plus project-specific ones for the dev-server URL and a test device ID. Key names in .env often differ from what specs read via Cypress.env(...) — the config file is the authority on that mapping.

   Verify .env exists and contains the required keys. Check key names only (cut -d= -f1 .env) — never print values. .env values are not exported to your shell; to use one in a command, extract it into a variable first:

   CYURL=$(grep '^<DEV_SERVER_URL_KEY>=' .env | cut -d= -f2- | tr -d '\r')
   

2. Dev server is up: curl -s -o /dev/null -w "%{http_code}" "$CYURL/apps/<C8Y_SHELL_TARGET value>/index.html" must return 200. If not, ask the user to start it (usually npm run start); do not start it yourself unless asked.

3. Tenant ID matches the base URL. This is a frequent silent breaker: .env files get copied between environments. Verify with the public endpoint:

   curl -s "$C8Y_BASEURL/tenant/loginOptions"
   

   The self links reveal the real tenant ID (e.g. https://t12345.…). If it differs from C8Y_TENANT, fix .env. Symptom of a mismatch: login fails with HTTP 400 "A tenant is required in context!".

4. Device ID exists (only if the test needs a device context):

   curl -s -o /dev/null -w "%{http_code}" -u "$C8Y_USERNAME:$C8Y_PASSWORD" "$C8Y_BASEURL/inventory/managedObjects/<device id>"
   

   On 404, find a real one: GET /inventory/managedObjects?fragmentType=c8y_IsDevice&pageSize=3 and update .env.

5. Dependencies are pre-installed (cumulocity-cypress, and ideally cypress-terminal-report for request traces). Do not install anything new without asking.