Leverage Docker Compose's .env file for environment variables

.dockerignore

@@ -1,2 +1,3 @@
 data
-output
+output
+.env

.env.example

@@ -0,0 +1,6 @@
+# Environment variables you define here are used for variable substitution in your Docker Compose file
+
+# The following keys are invalid and provided as an example only.
+# Please see the Managing Access Keys for IAM Users documentation (https://docs.aws.amazon.com).
+ODC_ACCESS_KEY=AKIAIOSFODNN7INVALID
+ODC_SECRET_KEY=wJalrXUtnFEMI/K7MDENG/bPxRfiCYINVALIDKEY

.gitignore

@@ -15,3 +15,4 @@ notebooks/.jupyter/
 notebooks/.local/
 notebooks/.bash_history
 notebooks/.python_history
+.env

README.md

@@ -29,3 +29,6 @@ You need to be logged in to the AWS Console deploy using this URL. Once logged i
 
 # IMPORTANT NOTES
 In your local environment, in order to be able to get data from S3, you need to ensure that the environment variables `ODC_ACCESS_KEY` and `ODC_SECRET_KEY` are set to something valid.
+
+##
+Environment variables can be set in a .env file for Docker Compose. You might use [.env.example](./.env.example) as a starting point.