Dockerizing Django projects

Transcript

1. Dockerizing Django projects Roberto Rosario robertorosario.com

2. Who am I? robertorosario.com me@robertorosario.com Roberto Rosario

3. None

4. What is Docker?

5. Docker provides an integrated technology suite that enables development and

   IT operations teams to build, ship, and run distributed applications anywhere.

6. In human now.

7. Containers.

8. Lightweight virtualization. ie: No video hardware emulation.

9. Some devops now hate me.

10. Deploy everywhere.

11. Easy scalability.

12. Even auto scaling.

13. Deploying Django: Old school.

14. None
15. None
16. None
17. None
18. None
19. None

20. Deployed! Congratulations!

21. Your users have now quadrupled!

22. None
23. None

24. Server are old, let’s go virtual!

25. None
26. None
27. None

28. Different technology, same problem.

29. None
30. None
31. None
32. None

33. Django and Docker?

34. Configuration files.

35. First steps.

36. None
37. None

38. Classes Instances

39. More devops hate me now.

40. None

41. Dockerfile

42. An entire OS for just a part of the Django

    project?

43. Not to worry.

44. None
45. None

46. Your Django project

47. Your Django project

48. Your Django project image Your Django project

49. Base image = Base class Your image = Subclass

50. Pretty much every devops hate me at this point.

51. One size doesn’t fit all.

52. Monolithic

53. App Workers Web server

54. docker run --name postgres -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e POSTGRES_PASSWORD=mysecretpassword

    -v /var/lib/postgresql/data -d postgres docker run --name redis -d redis docker run --name mayan-edms -p 80:80 --link postgres:postgres --link redis:redis -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e POSTGRES_PASSWORD=mysecretpassword -v /usr/local/lib/python2.7/dist- packages/mayan/media -d mayanedms/monolithic

55. • Single download • Low entry barrier • Easiest to

    maintain • Big size download • Not good for scaling • Same VM/Server problem

56. Split

57. App Workers Web server

58. Split ~ Frontend + Backend

59. • Scale individually • Smaller download • Best approach for

    production • Harder to setup • Need documentation • Several DockerFiles

60. Mixed

61. Role Frontend Backend

62. None

63. • Single download • Can reuse configuration file templates •

    Single core repo • Bigger size download

64. Lean

65. Lean = Split without any 3rd party

66. App Workers Web server

67. • Smallest download • Hardest to configure • Might not

    scale best • Might violate port export concept

68. Django + uWSGI NGINX

69. Django + uWSGI NGINX TCP Port uwsgi_pass 127.0.0.1:3031; socket =

    127.0.0.1:3031

70. Django + uWSGI NGINX socket = /tmp/uwsgi.sock uwsgi_pass unix:///tmp/uwsgi.sock; ?

71. Django + uWSGI NGINX socket = /tmp/uwsgi.sock uwsgi_pass unix:///tmp/uwsgi.sock; Volume?

72. • Need to include NGINX config

73. $ docker run --name some-nginx -v /some/nginx.conf:/etc/nginx/nginx.conf:ro -d nginx

74. environment: - NGINX_HOST=foobar.com - NGINX_PORT=80 command: /bin/bash -c "envsubst <

    /etc/nginx/conf.d/mysite.template > /etc/nginx/conf. d/default.conf && nginx -g 'daemon off;'"

75. Last approach

76. Kitchen sink

77. App Workers Database Web server Broker

78. • Single download • Lowest entry barrier • Biggest size

    download • Terrible for scaling • Same VM/Server problem • Support 3rd party software
79. None

80. Educational purposes only

81. Don’t use in production

82. EVER!

83. Kitchen sink will freeze your servers

84. Devops don’t like frozen servers

85. None

86. Don’t turn your devops into Gordon Ramsay

87. Post init actions

88. migrate & collectstatic

89. None
90. None
91. None
92. None

93. Service synchronization

94. $ docker run --name postgres -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e

    POSTGRES_PASSWORD=mysecretpassword -v /var/lib/postgresql/data -d postgres $ docker run --name redis -d redis $ docker run --name mayan-edms -p 80:80 --link postgres:postgres --link redis:redis -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e POSTGRES_PASSWORD=mysecretpassword -v /usr/local/lib/python2.7/dist- packages/mayan/media -d mayanedms/monolithic

95. Database connection error.

96. None

97. $ docker run --name postgres -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e

    POSTGRES_PASSWORD=mysecretpassword -v /var/lib/postgresql/data -d postgres $ docker run --name redis -d redis $ docker run --name mayan-edms -p 80:80 --link postgres:postgres --link redis:redis -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e POSTGRES_PASSWORD=mysecretpassword -v /usr/local/lib/python2.7/dist- packages/mayan/media -d mayanedms/monolithic

98. $ docker run --name postgres -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e

    POSTGRES_PASSWORD=mysecretpassword -v /var/lib/postgresql/data -d postgres $ docker run --name redis -d redis $ docker run --name mayan-edms -p 80:80 --link postgres:postgres --link redis:redis -e POSTGRES_DB=mayan -e POSTGRES_USER=mayan -e POSTGRES_PASSWORD=mysecretpassword -v /usr/local/lib/python2.7/dist- packages/mayan/media -d mayanedms/monolithic until nc -z $POSTGRES_PORT_5432_TCP_ADDR $POSTGRES_PORT_5432_TCP_PORT; do echo "$(date) - waiting for postgres..." sleep 1 done

99. Service synchronization doesn’t belong in configuration files.

100. until nc -z $POSTGRES_PORT_5432_TCP_ADDR $POSTGRES_PORT_5432_TCP_PORT; do echo "$(date) - waiting

     for postgres..." sleep 1 done until nc -z $RABBITMQ_PORT_5672_TCP_ADDR $RABBITMQ_PORT_5672_TCP_PORT; do echo "$(date) - waiting for rabbitmq..." sleep 1 done

101. More problems.

102. • Not foolproof • Mute services • nc is not

     universal • API URL paths?

103. Solutions?

104. None

105. $ docker run -d --name mycontainer some-image-or-other $ docker run

     --link mycontainer:mycontainer aanand/wait waiting for TCP connection to 172.17.0.105:5432......ok

106. Interesting, but...

107. None

108. An entire container to run nc.

109. Cool solution, wrong problem.

110. None
111. None

112. It’s the container manager’s responsibility.

113. None
114. None

115. Kubernetes approach

116. None

117. Port, path, initial delay & timeout!

118. None
119. None

120. Docker upstream native approach needed

121. None
122. None

123. Templating

124. Docker images are static. Less reusable.

125. None

126. Docker containers are configured with environment variables.

127. None

128. uWSGI support environment variables. NGINX doesn’t.

129. Docker upstream native approach needed

130. None
131. None

132. “Thank you for using Docker” “But your fix is in

     another repository”
133. None

134. Options?

135. None

136. And then there is genius

137. None
138. None

139. Bonus

140. None

141. Can help with logs too

142. None

143. Demo time

144. Lessons learned?

145. None
146. None
147. None
148. None
149. None

150. Thank you!