title: GOOGLE_APPLICATION_CREDENTIALS and GOOGLE_CLOUD_PROJECT setup in prod
body: <p>Like to know what is the best practice to store or reference these GOOGLE_APPLICATION_CREDENTIALS and GOOGLE_CLOUD_PROJECT in prod?</p>
  <pre><code>export GOOGLE_APPLICATION_CREDENTIALS=&quot;~/Download/key.json&quot;
  export GOOGLE_CLOUD_PROJECT=`gcloud config get-value project
  </code></pre>
  <p>as in dev these are likely to be in .zshrc so when running:</p>
  <pre><code>poetry run python3 samples/snippets/quickstart/pub.py $PROJECT hello_topic
  </code></pre>
  <p>to publish message is fine and we can see messages inside console portal, however:</p>
  <pre><code>poetry run pytest samples/snippets/quickstart/quickstart_test.py
  </code></pre>
  <p>ERROR samples/snippets/quickstart/quickstart_test.py::test_pub - google.api_core.exceptions.PermissionDenied: 403 User not authorized to perform this...</p>
  <p>.zshrc have already set:</p>
  <pre><code>export GOOGLE_APPLICATION_CREDENTIALS=&quot;$HOME/Documents/python-pubsub/key.json&quot;
  
  export GOOGLE_CLOUD_PROJECT=`gcloud config get-value project`
  </code></pre>
  <p>source .zshrc</p>