Update postgres-service.yml

.github/workflows/postgres-service.yml

@@ -12,6 +12,8 @@ jobs:
   container-job:
     runs-on: ubuntu-latest
     
+    # runs all of the steps inside the specified continer rather than on the VM host.  
+    # Because of this the network configuration changes from host based network to a container network.
     container:
       image:  node:10.16-jessie
 
@@ -34,11 +36,13 @@ jobs:
     - run: node client.js
       working-directory: ./postgres
       env:
-        # use postgres for the host here because we have specified a contaienr for the job.
+        # use postgres for the host here because we have specified a container for the job.
         # If we were running the job on the VM this would be localhost
         POSTGRES_HOST: postgres
         POSTGRES_PORT: ${{ job.services.postgres.ports[5432] }}
 
+# Runs all steps on the VM
+# The service containers will use host port binding instead of container networking so you access them via localhost rather than the service name
   vm-job:
     runs-on: ubuntu-latest
 
@@ -62,7 +66,7 @@ jobs:
     - run: node client.js
       working-directory: ./postgres
       env:
-        # use postgres for the host here because we have specified a contaienr for the job.
-        # If we were running the job on the VM this would be localhost
+        # use localhost for the host here because we have specified a container for the job.
+        # If we were running the job on the VM this would be postgres
         POSTGRES_HOST: localhost
         POSTGRES_PORT: ${{ job.services.postgres.ports[5432] }} # get randomly assigned published port