pull config from AppConfig if APP_ID is not empty

Dockerfile

@@ -55,6 +55,9 @@ COPY tests /data/tests
 RUN cp $SSP_PATH/modules/sildisco/sspoverrides/www_saml2_idp/SSOService.php $SSP_PATH/www/saml2/idp/
 RUN chmod a+x /data/run.sh /data/run-tests.sh
 
+ADD https://github.com/silinternational/config-shim/releases/latest/download/config-shim.gz config-shim.gz
+RUN gzip -d config-shim.gz && chmod 755 config-shim && mv config-shim /usr/local/bin
+
 EXPOSE 80
 ENTRYPOINT ["/usr/local/bin/s3-expand"]
 CMD ["/data/run.sh"]

README.md

@@ -11,6 +11,26 @@ must be installed.
 
 [Vagrant](https://www.vagrantup.com) for Windows users.
 
+## Configuration
+By default, configuration is read from environment variables. These are documented
+in the `local.env.dist` file. Optionally, you can define configuration in AWS AppConfig.
+To do this, set the following environment variables to point to the configuration in
+AWS:
+
+* `AWS_REGION` - the AWS region in use
+* `APP_ID` - the application ID or name
+* `CONFIG_ID` - the configuration profile ID or name
+* `ENV_ID` - the environment ID or name
+
+In addition, the AWS API requires authentication. It is best to use an access role
+such as an [ECS Task Role](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task-iam-roles.html).
+If that is not an option, you can specify an access token using the `AWS_ACCESS_KEY_ID` and
+`AWS_SECRET_ACCESS_KEY` variables.
+
+The content of the configuration profile takes the form of a typical .env file, using
+`#` for comments and `=` for variable assignment. Any variables read from AppConfig
+will overwrite variables set in the execution environment.
+
 ## Local testing
 
 1. `cp local.env.dist local.env` within project root and make adjustments as needed.

dockerbuild/run.sh

@@ -17,7 +17,11 @@ cd /data
 cat /etc/*release | grep PRETTY
 php -v | head -n 1
 
-apache2ctl -k start -D FOREGROUND
+if [[ -z "${APP_ID}" ]]; then
+  apache2ctl -k start -D FOREGROUND
+else
+  config-shim --app $APP_ID --config $CONFIG_ID --env $ENV_ID apache2ctl -k start -D FOREGROUND
+fi
 
 # endless loop with a wait is needed for the trap to work
 while true

local.env.dist

@@ -17,6 +17,22 @@ HUB_MODE=false
 IDPDISCO_LAYOUT=
 ENABLE_DEBUG=
 
+
+# === AWS AppConfig (optional) ===
+
+# The AWS region in use
+#AWS_REGION=
+
+# The AppConfig Application ID (or name)
+#APP_ID=
+
+# The AppConfig Configuration Profile ID (or name)
+#CONFIG_ID=
+
+# The AppConfig Environment ID (or name)
+#ENV_ID=
+
+
 # LOGGING_LEVEL default is NOTICE, or may be one of: ERR, WARNING, NOTICE, INFO, DEBUG
 LOGGING_LEVEL=