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README.md

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+# GoEnValue - a simple templates processor from environment variables.
+
+This tool very useful if you need to configure your containerised software.
+You can do it by passing environment variables into container on your Docker container start.
+
+How it works
+---
+You need to:
+ 1. create templates from your configuration files
+ 2. add in your entrypoint script state with execution of goenvalue
+ 3. build image with your software, templates and goenvalue
+ 4. run container with environment variables
+
+Example
+---
+**php.ini.tpl**
+```ini
+  ...
+  memory_limit = {{ .MEMORY_LIMIT }}
+  ...
+```
+
+**Dockerfile**
+```Dockerfile
+  FROM php:7
+  ENV PHP_MEMORY_LIMIT="64M"
+  COPY php.ini.tpl /etc/php/php.ini.tpl
+  COPY entrypoint.sh /entrypoint.sh
+  ...
+  ENTRYPOINT /entrypoint.sh
+```
+
+**entrypoint.sh**
+```bash
+  #!/bin/bash
+  goenvalue -p PHP -i /etc/php/php.ini.tpl
+  exec $@
+```
+
+Test it:
+```bash
+  $ docker run --rm -it -e PHP_MEMORY_LIMIT=128M my/php:7 php -i | grep memory_limit
+  memory_limit => 128M => 128M
+```