[circle] only attempt integration tests if we have a gce key

This will make fork PRs run successfully (but not run the integration
tests).

circle.yml

@@ -29,21 +29,35 @@ dependencies:
     - sudo apt-get install bc
     - pip install requests
     - curl https://sdk.cloud.google.com | bash
-    - bin/setup-circleci-secrets "$SECRET_PASSWORD"
+    - if [[ -n "$SECRET_PASSWORD" ]]; then
+        bin/setup-circleci-secrets "$SECRET_PASSWORD" ;
+        echo "Secrets Installed!" ;
+      fi
     - mkdir -p $(dirname $SRCDIR)
     - cp -r $(pwd)/ $SRCDIR
 
 test:
   override:
     - docker run -v /var/run/docker.sock:/run/docker.sock -v /home/ubuntu:/home/go weaveworks/weave-build:
         parallel: true
-    - cd $SRCDIR/test; ./gce.sh setup:
-        parallel: true
-    - cd $SRCDIR/test; . ./gce.sh hosts; ./setup.sh:
-        parallel: true
-    - cd $SRCDIR/test; . ./gce.sh hosts; ./run_all.sh:
+    - ? >
+        if [[ -e "/tmp/gce_private_key.json" ]]; then
+          cd $SRCDIR/integration;
+          ./gce.sh setup;
+          . ./gce.sh hosts;
+          ./setup.sh;
+          ./run_all.sh
+        else
+          echo "No GCE Credentials. Skipping integration tests..."
+        fi
+      :
         parallel: true
         timeout: 300
   post:
-    - cd $SRCDIR/test; ./gce.sh destroy:
+    - ? >
+        if [[ -e "/tmp/gce_private_key.json" ]]; then
+          cd $SRCDIR/integration;
+          ./gce.sh destroy;
+        fi
+      :
         parallel: true