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36 lines
1.1 KiB
36 lines
1.1 KiB
2 years ago
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# Lesson 6: Environment variables and configuration
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1. Change directory into `lesson06`.
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1. A popular way to provide configuration information to a docker container is
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via environment variables.
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1. Let's try it:
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$ docker build . -t demo
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$ docker run -it --rm --name fuzzle demo
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1. Does the output make sense?
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1. Let's pass in a value for the environment variable `HELLO_WORLD`:
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$ docker run -it --rm --name fuzzle -e HELLO_WORLD='Hello, world.' demo
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1. You can also pass in environment variables via a file:
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$ cat file.env
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# We define two environment variables (you CAN comment!)
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HELLO_WORLD="Hello, world."
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ENV_VAR2="another environment variable"
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$ docker run -it --rm --name fuzzle --env-file=file.env demo
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1. If your Docker application does not have many configuration options
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configuring via environment variables is a good method. However, if the
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application has complicated or extnesive configuration this may not be
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feasible.
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1. Don't forget to clean up:
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$ docker rmi demo:latest (removes the image demo:latest)
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