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readme.md

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+# nginx-envsubst
+
+A simple docker image for configuring nginx with environment variables.
+
+## Usage
+This image does not ship with a default configuration.
+To get started place your nginx config in `/etc/nginx/nginx.conf`
+and your normal server configurations in `/etc/nginx/sites-enabled/`.
+
+Every configuration file in `/etc/nginx/sites-available/` will get
+passed to `envsubst` and written to `/etc/nginx/sites-enabled/`.
+
+To specify which variables to substitute place a file
+`/environment_variables.txt` in the docker container with all variables
+which should be passed to envsubst.
+
+## Minimal Example
+
+```sh
+docker run \
+    -v "$PWD/nginx.conf":/etc/nginx/nginx.conf \
+    -v "$PWD/server.conf":/etc/nginx/sites-available/server.conf \
+    -v "$PWD/index.html":/var/www/html/index.html \
+    -e DOMAIN_NAME=localhost -p 80:80 \
+    redxef/nginx-envsubst:latest
+```