Theia Scale Tests

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This repository provides E2E integration tests for the Theia Cloud IDE. It uses Playwright to simulate real world usage of Online IDE's in large classroom settings.

Information

• Tests are written using Playwright
• Scaled tests run via the Playwright Artillery Framework or natively only using Playwright
• Make sure, that Sessions per User and max instanecs per App Definition is high enough set on the cluster!

Setup

• Setup Envionment Variables

  • Duplicate playwright.env.template and rename it to playwright.env (make sure this file is gitignored!)
  • Fill in the given variables as described in the file, notice:
    • Keycloak User and Password needs to have access to Theia (does not need to be the same Artemis User as of now)
    • Landing Page URL is the URL of the Theia Deployment to test against (this does not affect the Artemis Integration test, as the target deployment is set by Artemis)
    • The Artemis User needs to have enough priviliges to create a course and exercise on the given test server

• Get the latest Theia IDE image from here and run it. Put the corresponding URL into the env file

• Install dependencies and playwright browser

  pnpm install

  pnpm exec playwright install

Run Tests

• To run the functional tests on the deployed Theia instance, run:

  pnpm exec playwright test --project=functional

• To run tests locally using a Theia Instance on localhost, change the environment variable to the corresponding port and run the tests using:

  pnpm exec playwright test --project=local

• To run the load tests, run:

  NOTE: As load tests use a single account, pay attention that the session per user limit is min the amount of instances you want!

  pnpm exec playwright test --project=scale

  Set the amount of instances in the ENV file or pass it like this (ex. 100 instances):

  NUM_INSTANCE=100 pnpm exec playwright test --project=scale

  To run the tests using the Artillery.io framework, run:

  pnpm exec artillery run tests/ide/scalable/artillery/Artillery.ts

• To run the MCP tests, follow the README in the MCP folder

• To run the benchmark manually for one flavour, run:

  BENCH_TARGET_APP=java-17-no-ls BENCH_ARCH=external BENCH_MODE=warm BENCH_SCENARIO=simple-type-error pnpm exec playwright test tests/ide/benchmark/LSLatency.ui.benchmark.spec.ts --project=benchmark --headed --workers=1 --reporter=line --no-deps --retries=0

  Optional benchmark env vars:

  • BENCH_SCENARIO=simple-type-error Selects the benchmark scenario. Supported values are simple-type-error, import-semantic-error, and hover-context.
  • BENCH_HELPER_FILE=src/bench/BenchHelper.java Helper file path used by the semantic-import and hover scenarios.
  • BENCH_POST_ERROR_SETTLE_MS=2000 Adds a short delay after a squiggly/diagnostic appears before the benchmark continues with the next step. The latency itself is still measured at first appearance.
  • BENCH_HOVER_WARMUP_MS=45000 Adds a fixed warmup wait before hover measurements start so the language server can finish initial project setup.
  • BENCH_HOVER_RESOLVE_TIMEOUT_MS=15000 Hover measurements wait for real hover content up to this timeout. Loading... does not count as a result.

  Scenario notes:

  • simple-type-error Uses two imports and injects a local type mismatch (int = "x").
  • import-semantic-error Uses a project-local imported helper class and injects a semantic type mismatch based on the imported method result.
  • hover-context Uses the same imported helper class and measures how fast resolved Monaco hover content appears for three fixed tokens (ArrayList, BenchHelper, compute). A temporary Loading... tooltip is ignored.
  • The benchmark setup initializes a minimal Eclipse/JDT Java project in the workspace via terminal before creating the scenario files (.project, .classpath, .settings/org.eclipse.jdt.core.prefs).

• To improve resource metric freshness for the benchmark on theia-prod, temporarily lower the Prometheus kubelet cAdvisor scrape interval to 5s:

  kubectl --context theia-prod -n cattle-monitoring-system patch servicemonitor rancher-monitoring-kubelet --type='json' -p='[{"op":"add","path":"/spec/endpoints/1/interval","value":"5s"}]'

  Verify that Prometheus picked it up:

  kubectl --context theia-prod get --raw '/api/v1/namespaces/cattle-monitoring-system/services/http:rancher-monitoring-prometheus:9090/proxy/api/v1/status/config' | jq -r '.data.yaml' | sed -n '1598,1622p'

  Revert after the benchmark campaign:

  kubectl --context theia-prod -n cattle-monitoring-system patch servicemonitor rancher-monitoring-kubelet --type='json' -p='[{"op":"replace","path":"/spec/endpoints/1/interval","value":"15s"}]'

• To aggregate benchmark artifacts in test-data/benchmark, run:

  pnpm run bench:aggregate

• To run the benchmark with Prometheus-backed resource monitoring against a deployed namespace, run:

  bash scripts/run-benchmark.sh --context <kube-context> --namespace <namespace> --target-app java-17-no-ls --arch external --mode warm --scenario import-semantic-error --runs 1 --probes 5 --headed

  The resource collector reads container CPU and memory from Prometheus cAdvisor metrics and stores them in test-data/.../raw/resource-raw.csv.

  If the benchmark setup is hard to reproduce from this cleaned test-suite branch, compare against the development branch feature/benchmark-test3-ui-latency, which contains the original local benchmark campaign state and debugging history.

Project Identifier	Description	Status
local	Runs all functional tests on a local instance, provided by the URL in the env file.
functional	Runs all functional tests on the deployed instance, provided by the URL in the env file.
scale	Runs all scalability tests on the deployed instance, provided by the URL in the env file.
artillery	Runs the scalability test on the deployed instance, using the Artillery.io framework.
artemis	Runs the integration test with Artemis, either local or deployed depending on the URLs set in the env file.
*-setup	These are setup projects and not meant to be run on its own. Dependencies are already set.

Development

• Single User Playwright Tests are run using a Test Account for Keycloak, to change the Test User, change the environment variables in GitHub Secrets
  -> Settings -> Secrets and variables -> Actions -> Secrets -> Repository Secrets

• All functional tests (that can also be run on a local instance) have the following file format:

  *.functional.spec.ts
  

• All scalable tests (that can only be run on a scalable supported instance) have the following file format:

  *.scale.spec.ts
  

• Tests require to have a specific setup files run before them. These are normally already run by requirements of the playwright.config.ts

• The tests safe the URL for each instance in a text file under /test-data for debugging and to access them in the tests

• Tests are intended to run on the production environment (https://theia.artemis.cit.tum.de)

  • As tests include testing of all available programming languages: local images for each language can be found here: https://github.com/orgs/ls1intum/packages?repo_name=artemis-theia-blueprints

Info

This repository contains code from:

• Eclipse Theia: https://github.com/eclipse-theia/theia/tree/master/examples/playwright
• Artemis: https://github.com/ls1intum/Artemis/tree/develop/src/test/playwright
• MCP: https://github.com/modelcontextprotocol/quickstart-resources/tree/main/mcp-client-typescript