Write a python web case, use compose choreography services. Examples comprising two containers, a python web container, a container is Redis database.
First constructed python web mirroring and containers:
(1) create composeapp directory.
[root@client /]# mkdir composeapp
[root@client /]# cd composeapp/
[root@client composeapp]# touch Dockerfile
(2) Write the python program
[root@client composeapp]# touch app.py
[root@client composeapp]# vi app.py
from flask import Flask
from redis import Redis
import os
app = Flask(__name__)
redis = Redis(host="redis", port=6379)
@app.route('/')
def hello():
redis.incr('hits')
return 'Hello Docker Book reader! I have been seen {0} times'.format(redis.get('hits'))
if __name__ == "__main__":
app.run(host="0.0.0.0", debug=True)
（3）. 创建python的依赖包描述文件
~ [root@client composeapp]# touch requirements.txt
[root@client composeapp]# vi requirements.txt
flask
redis
(4) Write the image file python web containers Dockerfile
[root@client composeapp]# vi Dockerfile
FROM python:2.7
MAINTAINER James Turnbull <[email protected]>
ENV REFRESHED_AT 2016-08-01
ADD . /composeapp
WORKDIR /composeapp
RUN pip install -r requirements.txt
(5) Construction of the mirror
[root@client composeapp]# sudo docker build -t jamtur01/composeapp .
[root@client composeapp]# sudo docker build -t jamtur01/composeapp .
Sending build context to Docker daemon 4.096 kB
Step 1 : FROM python:2.7
Trying to pull repository 192.168.200.11:5000/python ...
Pulling repository 192.168.200.11:5000/python
Error: image python not found
Trying to pull repository docker.io/library/python ...
2.7: Pulling from docker.io/library/python
75a822cd7888: Pull complete
57de64c72267: Pull complete
4306be1e8943: Pull complete
871436ab7225: Pull complete
37c937b0ca47: Pull complete
608a51124afe: Pull complete
086c59e7b25f: Pull complete
Digest: sha256:43b6a6df624798dd8889bde2c02a48a263faa1d72f0de9e134de84c4079ac365
Status: Downloaded newer image for docker.io/python:2.7
---> acf0d719f268
Step 2 : MAINTAINER James Turnbull <[email protected]>
---> Running in 19e30769bcd3
---> 6efea2b07fec
Removing intermediate container 19e30769bcd3
Step 3 : ENV REFRESHED_AT 2016-08-01
---> Running in 1c55d12d766b
---> fdf17727b383
Removing intermediate container 1c55d12d766b
Step 4 : ADD . /composeapp
---> 96618268b61c
Removing intermediate container cd7b0ed6e203
Step 5 : WORKDIR /composeapp
---> Running in 5f04f2e5adca
---> c504ecdffde0
Removing intermediate container 5f04f2e5adca
Step 6 : RUN pip install -r requirements.txt
---> Running in 7433546dcc5c
Collecting flask (from -r requirements.txt (line 1))
Downloading Flask-0.12-py2.py3-none-any.whl (82kB)
Collecting redis (from -r requirements.txt (line 2))
Downloading redis-2.10.5-py2.py3-none-any.whl (60kB)
Collecting itsdangerous>=0.21 (from flask->-r requirements.txt (line 1))
Downloading itsdangerous-0.24.tar.gz (46kB)
Collecting Jinja2>=2.4 (from flask->-r requirements.txt (line 1))
Downloading Jinja2-2.8-py2.py3-none-any.whl (263kB)
Collecting Werkzeug>=0.7 (from flask->-r requirements.txt (line 1))
Downloading Werkzeug-0.11.13-py2.py3-none-any.whl (308kB)
Collecting click>=2.0 (from flask->-r requirements.txt (line 1))
Downloading click-6.6-py2.py3-none-any.whl (71kB)
Collecting MarkupSafe (from Jinja2>=2.4->flask->-r requirements.txt (line 1))
Downloading MarkupSafe-0.23.tar.gz
Building wheels for collected packages: itsdangerous, MarkupSafe
Running setup.py bdist_wheel for itsdangerous: started
Running setup.py bdist_wheel for itsdangerous: finished with status 'done'
Stored in directory: /root/.cache/pip/wheels/fc/a8/66/24d655233c757e178d45dea2de22a04c6d92766abfb741129a
Running setup.py bdist_wheel for MarkupSafe: started
Running setup.py bdist_wheel for MarkupSafe: finished with status 'done'
Stored in directory: /root/.cache/pip/wheels/a3/fa/dc/0198eed9ad95489b8a4f45d14dd5d2aee3f8984e46862c5748
Successfully built itsdangerous MarkupSafe
Installing collected packages: itsdangerous, MarkupSafe, Jinja2, Werkzeug, click, flask, redis
Successfully installed Jinja2-2.8 MarkupSafe-0.23 Werkzeug-0.11.13 click-6.6 flask-0.12 itsdangerous-0.24 redis-2.10.5
---> e031fec32547
Removing intermediate container 7433546dcc5c
Successfully built e031fec32547
(6) to docker run run case:
[root@client composeapp]# sudo docker run -d -p 5000:5000 -v .:/composeapp --link redis:redis --name jamtur01/composeapp python app.py
Unable to find image 'python:latest' locally
Trying to pull repository 192.168.200.11:5000/python ...
Pulling repository 192.168.200.11:5000/python
Error: image python not found
Trying to pull repository docker.io/library/python ...
latest: Pulling from docker.io/library/python
75a822cd7888: Already exists
57de64c72267: Already exists
4306be1e8943: Already exists
871436ab7225: Already exists
37c937b0ca47: Already exists
2172fb7edb3a: Pull complete
dcec4e4061ab: Pull complete
Digest: sha256:1fa4d0110c7093fdb1306b4b290824a37169ca6a19f091b7227967647726169a
Status: Downloaded newer image for docker.io/python:latest
docker: Error response from daemon: Invalid container name (jamtur01/composeapp), only [a-zA-Z0-9][a-zA-Z0-9_.-] are allowed.
See '/usr/bin/docker-current run --help'.
(7) to docker-compose run case:
build Docker Compose yml file the following: docker-compose.yml file:
[root@server composeapp]# vi docker-compose.yml
web:
image: jamtur01/composeapp
command: python app.py
ports:
- "5000:5000"
volumes:
- .:/composeapp
links:
- redis
redis:
image: redis
切换到composeapp目录下，以compose的方式运行
[root@server composeapp]#
[root@server composeapp]# sudo docker-compose up
Pulling redis (redis:latest)...
Trying to pull repository 192.168.200.18:5000/redis ...
Pulling repository 192.168.200.18:5000/redis
Error: image redis not found
Trying to pull repository docker.io/library/redis ...
latest: Pulling from docker.io/library/redis
75a822cd7888: Already exists
e40c2fafe648: Pull complete
ce384d4aea4f: Pull complete
5e29dd684b84: Pull complete
29a3c975c335: Pull complete
a405554540f9: Pull complete
4b2454731fda: Pull complete
Digest: sha256:be03cb3b2e0d290c3d6670d1843b6036c1914663574bb624ffb62535344de5b4
Status: Downloaded newer image for docker.io/redis:latest
Creating composeapp_redis_1
Creating composeapp_web_1
Attaching to composeapp_redis_1, composeapp_web_1
redis_1 | 1:C 01 Jan 12:35:45.005 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
redis_1 | _._
redis_1 | _.-``__ ''-._
redis_1 | _.-`` `. `_. ''-._ Redis 3.2.6 (00000000/0) 64 bit
redis_1 | .-`` .-```. ```\/ _.,_ ''-._
redis_1 | ( ' , .-` | `, ) Running in standalone mode
redis_1 | |`-._`-...-` __...-.``-._|'` _.-'| Port: 6379
redis_1 | | `-._ `._ / _.-' | PID: 1
redis_1 | `-._ `-._ `-./ _.-' _.-'
redis_1 | |`-._`-._ `-.__.-' _.-'_.-'|
redis_1 | | `-._`-._ _.-'_.-' | http://redis.io
redis_1 | `-._ `-._`-.__.-'_.-' _.-'
redis_1 | |`-._`-._ `-.__.-' _.-'_.-'|
redis_1 | | `-._`-._ _.-'_.-' |
redis_1 | `-._ `-._`-.__.-'_.-' _.-'
redis_1 | `-._ `-.__.-' _.-'
redis_1 | `-._ _.-'
redis_1 | `-.__.-'
redis_1 |
redis_1 | 1:M 01 Jan 12:35:45.008 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
redis_1 | 1:M 01 Jan 12:35:45.008 # Server started, Redis version 3.2.6
redis_1 | 1:M 01 Jan 12:35:45.008 # WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.
redis_1 | 1:M 01 Jan 12:35:45.008 # WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled.
redis_1 | 1:M 01 Jan 12:35:45.008 * The server is now ready to accept connections on port 6379
web_1 | * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)
web_1 | * Restarting with stat
web_1 | * Debugger is active!
web_1 | * Debugger pin code: 457-652-386
web_1 | 192.168.0.51 - - [01/Jan/2017 12:37:42] "GET / HTTP/1.1" 200 -
web_1 | 192.168.0.51 - - [01/Jan/2017 12:37:42] "GET /favicon.ico HTTP/1.1" 404 -
Finally, to verify the effect on the following pages:
