Deploying with Docker (SymfonyTN)

Docker, l'une des technologies les plus en vogue ces derniers temps, permet de créer des conteneurs logiciels. Retour sur mon utilisation pour le développement mais également pour la production, avec en ligne de mire : une architecture micro-services, quelques principes 12 Factors et un déploiement en (presque) "zero-downtime".

Online slides: http://slides.williamdurand.fr/deploying-with-docker/
Sources: https://github.com/willdurand-slides/deploying-with-docker

Transcript

1. Deploying with William Durand ‑ April 17th, 2015
2. Docker In A Nutshell
3. Containers A container is an operating‑system level virtualization method that provides a completely isolated environment, simulating a closed system running on a single host. chroot, OpenVZ, Jail, LXC, etc.
4. Containers vs VMs
5. Docker Developed by Docker.inc (formerly DotCloud) Open platform for developing, shipping, and running applications Use as execution driver libcontainer
6. Docker's Architecture Host Container 1 Container 2 Container 3 Container ... Docker Client docker pull docker run docker ... Docker Index Docker Daemon
7. Try It!
8. The Plan Simple solution to deploy my application Idempotent and reliable process No need for rollbacks Targetting zero downtime Single host
9. Methodology
10. Twelve Factors One codebase tracked in revision control, many deploys Store config in the environment Keep development, staging, and production as similar as possible 12factor.net
11. Infrastructure
12. Services Reverse proxy: (+ ) Backend: + + application Sessions are stored into Database (MySQL) Hipache Redis Nginx HHVM memcached
13. Overall Architecture
14. Application's fig.yml web: build: . # No support for `env-file` yet... # See: https://github.com/docker/fig/pull/665 environment: - SYMFONY_ENV=dev - SYMFONY_DEBUG=1 - SYMFONY__MEMCACHED_HOST=memcached - SYMFONY__MEMCACHED_PORT=11211 - SYMFONY__SESSION_MEMCACHED_PREFIX=session - SYMFONY__SESSION_MEMCACHED_EXPIRE=604800 links: - memcached - database
15. Data Only Containers Data, logs, etc. MUST live in data only containers: # fig.yml redis: image: redis volumes_from: - dataredis dataredis: image: busybox volumes: - /data Wanna backup? ė docker run --rm \ --volumes-from dataredis \ -v $(pwd):/backup \ busybox \ tar cvf /backup/dataredis.tgz /data
16. Application's Dockerfile FROM debian:wheezy MAINTAINER William Durand <will@drnd.me> ENV DEBIAN_FRONTEND noninteractive # Let APT know about HHVM repo... RUN apt-get update -y RUN apt-get install -y nginx hhvm supervisor # Configure Nginx, HHVM, Supervisor here... ADD . /app WORKDIR /app EXPOSE 80 CMD [ "/usr/bin/supervisord" ]
17. DNS example.org w www.example.org Configured at the DNS level. Faster than making this redirection using the load balancer.
18. SSL Hipache listens on ports 80 and 443. Patched version of Hipache to redirect HTTP traffic to HTTPS. Sort of SSL offloading. ® willdurand/docker‑hipache
19. Deploy
20. 1. Build Artifact git archive --format tar --prefix myapp/ <SHA> | (cd /tmp && tar xf -) Protip: use a Docker container to run : build tools cd /tmp/myapp docker run --rm -v `pwd`:/srv buildtools composer install docker run --rm -v `pwd`:/srv buildtools bundle install docker run --rm -v `pwd`:/srv buildtools bower install rm <USELESS/TEMP FILES>
21. 2. Build Container (From Artifact) docker build -t myapp:latest .
22. 3. Push It docker push q Or whatever that makes the image available on the production server.
23. 4. Retrieve Running Containers RUNNING_CIDS=$(docker ps | grep web | cut -d ' ' -f 1)
24. 5. Run The New Container fig run -d --no-deps --rm web † Booting the container may take a few seconds, wait.
25. 6. Register It As Backend IP=$(docker inspect --format='{{ .NetworkSettings.IPAddress }}' <CID>) fig run --rm rediscli rpush frontend:www.example.com "http://$IP:80" # fig.yml rediscli: image: redis entrypoint: [ redis-cli, -h, redis ] links: - redis
26. 7. Unregister Previous Backends For each container id CID in $RUNNING_CIDS, do: IP=$(docker inspect --format='{{ .NetworkSettings.IPAddress }}' <CID>) fig run --rm rediscli lrem frontend:www.example.com 0 "http://$IP:80" † New backend is up and serves requests. However, previous backends may still process requests. Wait.
27. 8. Stop Previous Containers For each container id CID in $RUNNING_CIDS, do: docker stop <CID>
28. 9. Tag A Release (And Profit!)
29. Database Migrations
30. This Is My Vision Use (or ) to write your migration scripts Put you migration scripts under version control Test your migration scripts Applying your migration scripts should be done asynchronously (i.e. not tied to a deployment) This is tricky (i.e. not easy) You need a plan! Phinx Flyway
31. Adding A New Column/Table 1. Prepare your migration before modifying your code 2. Apply your migration 3. Update your code
32. Modifying A Column Type 1. Create a new column with the new type as a migration 2. Apply your migration 3. Create a migration to populate the new column 4. Apply your second migration 5. Update your code to use this new column (your code should deal with both columns) 6. Rename the first column as "deprecated", and the new one using the original name 7. Remove hacks introduced in 5
33. Renaming A Column/Table 1. Create a new column or table with the new name rather than "renaming" it 2. Apply your migration 3. Update your code to use the new column/table but keep using the former 4. Create a migration to populate the new column/table 5. Apply your migration 6. Update your code to use the new column/table 7. Rename the former column/table as "deprecated" 8. Remove hacks introduced in 3
34. Deleting A Column/Table Rename it rather than deleting it. Wait for a maintenance party to delete *_deprecated columns and/or tables. Protip: when marking a column/table as deprecated, add the date too: _deprecated_2015_01_01.
35. Making Changes On The Data Avoid it as long as you can, but sometimes, there are no other alternatives. This implies a maintenance mode: be careful! 1. Put your service in maintenance mode 2. Apply your changes 3. Put your service back online
36. Benchmarking
37. Like , but better! Apache Bench ® tarekziade/boom
38. 1. Run boom boom https://www.example.org/ -n 2000 -c 50 Server Software: nginx/1.2.1 Running GET https://www.example.org/ Running 2000 times per 50 workers. [====================================================>.] 99% Done -------- Results -------- Successful calls 2000 Total time 137.1827 s Average 6.7114 s Fastest 2.3701 s Slowest 9.4738 s Amplitude 7.1037 s -------- Status codes -------- Code 200 2000 times.
39. 2. Deploy fab deploy --hide=running,stdout,stderr ---> Deploying branch "awesome-feature" ---> Building artifact ---> Artifact id is: "build-8fe47fc" ---> Pushing artifact to the server ---> Building container ---> Finding running containers ---> Starting new container ---> Waiting while container is booting ---> Registering new backend to Hipache ---> Unregistering the previous backends from Hipache ---> Waiting before stopping the previous backends Done. q I use . Fabric
40. 3. Monitor Elasticsearch, Logstash, Kibana + Logstash Forwarder (lumberjack) ® willdurand/docker‑elk ® willdurand/docker‑logstash‑forwarder
42. Testing
44. wercker.yml box: wercker-labs/docker build: steps: - script: name: install Fig code: | curl -L https://.../fig-`uname -s`-`uname -m` > fig ; chmod +x fig sudo mv fig /usr/local/bin/fig - ...
45. 1. Build Artifact - script: name: build artifact code: | FAB_DIST_DIR="$WERCKER_OUTPUT_DIR" \ bin/fabric build:commit="$WERCKER_GIT_COMMIT"
46. 2. Build a Docker Image - script: name: build image code: | cd "$WERCKER_OUTPUT_DIR/build-$WERCKER_GIT_COMMIT" fig -f "$WERCKER_SOURCE_DIR/fig.yml.dist" build web
47. 3. Run a Container - script: name: run container code: | cd "$WERCKER_OUTPUT_DIR/build-$WERCKER_GIT_COMMIT" fig -f "$WERCKER_SOURCE_DIR/fig.yml.dist" run -d web sleep 20
48. 4. Run Tests \o/ - script: name: run test suite code: | export IP=$(docker inspect --format='{{ .NetworkSettings.IPAddress }}'\ "$(docker ps -q | head -n 1)") echo "IP address is: $IP" | tee "$WERCKER_REPORT_MESSAGE_FILE" bin/test
49. Smoke Testing require "httparty" describe "The web server" do before(:all) do ip = ENV["IP"] or 'localhost' @response = HTTParty.get( "http://#{ip}:80", :basic_auth => { :username => "privatedemo", :password => "please" } ) end it "should return a 200 status code" do @response.code.should == 200 end end + = 쁥 RSpec httparty
51. Thank You. Questions? ¾ ® ¬ williamdurand.fr github.com/willdurand twitter.com/couac
52. Bonus
53. Fig & Environments Keep development, staging, and production as similar as possible X. Dev/prod parity — 12 Factors # fig.yml.dist web: # In PRODUCTION, the line below MUST be COMMENTED: build: . # In PRODUCTION, the line below must be UNCOMMENTED: # image: myapp # ...