feat(build): Add an integration test that runs on Travis

This test, after performing the usual Nixery build, loads the built
image into Docker, runs it, pulls an image from Nixery and runs that
image.

To make this work, there is some configuration on the Travis side.
Most importantly, the following environment variables have special
values:

* `GOOGLE_KEY`: This is set to a base64-encoded service account key to
  be used in the test.
* `GCS_SIGNING_PEM`: This is set to a base64-encoded signing key (in
  PEM) that is used for signing URLs.

Both of these are available to all branches in the Nixery repository.

1 files changed, 47 insertions, 2 deletions

diff --git a/tools/nixery/.travis.yml b/tools/nixery/.travis.yml
index 96f1ec0fc15b..950de21f70c6 100644
--- a/tools/nixery/.travis.yml
+++ b/tools/nixery/.travis.yml
@@ -1,6 +1,51 @@
 language: nix
+services:
+  - docker
 before_script:
-  - nix-env -iA nixpkgs.cachix
-  - cachix use nixery
+  - |
+    mkdir test-files
+    echo ${GOOGLE_KEY} | base64 -d > test-files/key.json
+    echo ${GCS_SIGNING_PEM} | base64 -d > test-files/gcs.pem
+    nix-env -iA nixpkgs.cachix -A nixpkgs.go
+    cachix use nixery
 script:
+  - test -z $(gofmt -l server/ build-image/)
   - nix-build | cachix push nixery
+
+  # This integration test makes sure that the container image built
+  # for Nixery itself runs fine in Docker, and that images pulled
+  # from it work in Docker.
+  #
+  # Output from the Nixery container is printed at the end of the
+  # test regardless of test status.
+  - IMG=$(docker load -q -i $(nix-build -A nixery-image) | awk '{ print $3 }')
+  - echo "Loaded Nixery image as ${IMG}"
+
+  - |
+    docker run -d -p 8080:8080 --name nixery \
+      -v ${PWD}/test-files:/var/nixery \
+      -e PORT=8080 \
+      -e BUCKET=nixery-layers \
+      -e GOOGLE_CLOUD_PROJECT=nixery \
+      -e GOOGLE_APPLICATION_CREDENTIALS=/var/nixery/key.json \
+      ${IMG}
+
+  # print all of the container's logs regardless of success
+  - |
+    function print_logs {
+      echo "Nixery container logs:"
+      docker logs nixery
+    }
+    trap print_logs EXIT
+
+  # Give the container ~20 seconds to come up
+  - |
+    attempts=0
+    echo -n "Waiting for Nixery to start ..."
+    until $(curl --fail --silent "http://localhost:8080/v2/"); do
+      [[ attempts -eq 30 ]] && echo "Nixery container failed to start!" && exit 1
+      ((attempts++))
+      echo -n "."
+      sleep 1
+    done
+  - docker run --rm localhost:8080/hello hello