feat(docker): split docker-compose UI and gateway into separate services

[yassin-berriai]

Summary

Resolves LIT-2815

The monolithic litellm service in docker-compose.yml served both the LLM API and the admin UI from a single container. This PR splits it into two independent services:

• gateway — FastAPI/uvicorn API proxy (port 4000), built from gateway/Dockerfile
• ui — nginx/Next.js admin dashboard (port 3000), built from ui/Dockerfile

The gateway uses depends_on: db: condition: service_healthy so it waits for Postgres to pass pg_isready before starting (avoids connection-refused on cold boot).

Changes

File	Change
docker-compose.yml	Replace litellm service with ui + gateway; gateway waits for db health
prometheus.yml	Update scrape target: litellm:4000 → gateway:4000
ui/litellm-dashboard/build_ui.sh	Atomic rm+mv instead of rm -rf * + cp
tests/test_litellm/test_docker_compose.py	17 new static checks (see test matrix below)

Test Matrix

Scenario	Expected	Result
ui service exists	present in services dict	✅
gateway service exists	present in services dict	✅
Legacy litellm service is gone	absent from services dict	✅
ui builds from ui/Dockerfile	build.dockerfile == "ui/Dockerfile"	✅
gateway builds from gateway/Dockerfile	build.dockerfile == "gateway/Dockerfile"	✅
ui exposes port 3000	exact "3000:3000" in ports	✅
gateway exposes port 4000	exact "4000:4000" in ports	✅
gateway has DATABASE_URL env var	key present in environment	✅
gateway has STORE_MODEL_IN_DB env var	key present in environment	✅
gateway health check configured	healthcheck.test non-empty	✅
ui health check configured	healthcheck.test non-empty	✅
gateway depends on db with service_healthy	dict form with condition: service_healthy	✅
db service exists	present in services dict	✅
db health check configured	healthcheck.test non-empty	✅
prometheus service exists	present in services dict	✅
Named volume postgres_data is declared	key present in top-level volumes dict	✅
prometheus.yml scrapes gateway:4000	target contains "gateway"	✅
prometheus.yml does not reference litellm:4000	old target absent	✅

All 17 tests pass (uv run pytest tests/test_litellm/test_docker_compose.py -v).

Migration note

Users who have a local prometheus.yml pointing at litellm:4000 should update the target to gateway:4000. The documentation PR (BerriAI/litellm-docs#210) updates the quick-start guide accordingly.

https://claude.ai/code/session_01LoB2H4kqJM5cFS98gV8GPY

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[yassin-berriai]

@greptileai

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Generated by Claude Code

[greptile-apps]

Greptile Summary

This PR splits the monolithic litellm Docker service into two independent services — gateway (FastAPI/uvicorn on port 4000) and ui (nginx/Next.js on port 3000) — and updates prometheus.yml to scrape the renamed gateway service. Both services get their own Dockerfiles, healthchecks, and the gateway now properly waits for Postgres readiness via condition: service_healthy.

• docker-compose.yml: litellm service removed; gateway uses depends_on: db: condition: service_healthy and carries over all existing environment variables and healthcheck config; ui is a new nginx-served frontend service with its own healthcheck.
• tests/test_litellm/test_docker_compose.py: 17 new static checks verify service presence, build config, exact port mappings, env vars, healthchecks, and Prometheus target; port assertions use exact string equality.
• build_ui.sh: rm -rf dir && mv out dir replaces the old multi-step copy, making the output handoff atomic.

Confidence Score: 5/5

Safe to merge — the changes are confined to Docker/infra config and a new static test file, with no modifications to application logic.

All application code is untouched. The docker-compose split is clean, the service_healthy dependency is correctly wired, and the new tests use exact port-equality assertions. The only gap is a minor one in the test's else branch for depends_on, which has no effect on the current configuration.

No files require special attention; the minor test-coverage gap in test_gateway_depends_on_db is low risk.

Important Files Changed

Filename	Overview
docker-compose.yml	Splits monolithic litellm service into ui (nginx/Next.js, port 3000) and gateway (FastAPI, port 4000); gateway now uses condition: service_healthy for depends_on: db, and both services have healthchecks configured.
prometheus.yml	One-line update: scrape target changed from litellm:4000 to gateway:4000 to match the renamed service.
tests/test_litellm/test_docker_compose.py	New static-analysis test file with 17 checks; port assertions now use exact equality; test_gateway_depends_on_db verifies service_healthy in the dict branch but the else branch skips that check, leaving a small coverage gap.
ui/litellm-dashboard/build_ui.sh	Replaced rm -rf dir/* && cp -r out/* dir && rm -rf out with the cleaner rm -rf dir && mv out dir, making the build output replacement atomic and resilient to a missing destination directory.

_{Reviews (2): Last reviewed commit: "fix(docker): address Greptile review and..." | Re-trigger Greptile}

[yassin-berriai]

Addressed both items from the 4/5 review:

1. depends_on readiness — switched gateway from the list form to condition: service_healthy, so it won't start until pg_isready passes on the db container.
2. Port-test exactness — replaced substring matching with exact "3000:3000" / "4000:4000" string equality; also extended test_gateway_depends_on_db to assert the service_healthy condition.

Also restored uv.lock to its pre-test-run state (the previous commit had dropped the [options] exclude-newer section because local uv couldn't parse the relative "3 days" duration, breaking uv lock --check and uv sync --frozen in CI).

@greptileai

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Generated by Claude Code