Publish image automatically (#205)

* Build docker image for every commit

In order to make sure that we don't introduce any issue on PRs.

* Publish docker images automatically

From now on, every merge will update the `nightly` docker tag and tagged
jobs will create a docker tag with the same name of the git tag and also
update the `latest` docker tag.

* Build the image from source instead

To allow us to replay the build of a revision as many times as we want
and prevent possible version inconsistencies.

* Expose default port by default

Which allows the command "serve" to be used via docker too.

* Validate docker image on CI

Author: lcobucci

.circleci/config.yml

@@ -42,6 +42,23 @@ jobs:
             - image: circleci/node:8
         <<: *shared
 
+    build-image:
+        machine: true
+        steps:
+            - checkout
+            - run: docker run --rm -i hadolint/hadolint < Dockerfile
+            - run: docker build -t speccy:$CIRCLE_SHA1 .
+
+    push-image:
+        machine: true
+        steps:
+            - checkout
+            - run: docker build -t speccy:$CIRCLE_SHA1 .
+            - run: docker login -u $DOCKER_LOGIN -p $DOCKER_PASSWORD
+            - run: docker tag speccy:$CIRCLE_SHA1 wework/speccy:nightly
+            - run: if [ "$CIRCLE_TAG" != "" ]; then docker tag speccy:$CIRCLE_SHA1 wework/speccy:latest; fi;
+            - run: if [ "$CIRCLE_TAG" != "" ]; then docker tag speccy:$CIRCLE_SHA1 wework/speccy:$CIRCLE_TAG; fi;
+
 workflows:
     version: 2
     commit:
@@ -50,3 +67,14 @@ workflows:
             - node-10
             - node-9
             - node-8
+            - build-image
+
+    deploy:
+        jobs:
+            - push-image:
+                filters:
+                    branches:
+                        only: master
+                    tags:
+                        only: /.*/
+

.dockerignore

@@ -0,0 +1,12 @@
+/.circleci
+/.git
+/.github
+/*.md
+/Dockerfile
+/docs
+/.dockerignore
+/.editorconfig
+/.eslintrc.json
+/.gitignore
+/test
+

Dockerfile

@@ -1,11 +1,25 @@
+FROM node:11.1-alpine as builder
+
+WORKDIR /opt/speccy
+
+COPY . /opt/speccy/
+
+ENV NODE_ENV=production
+
+# Ignore version locking to avoid undesired breaks due to changes in upstream
+# hadolint ignore=DL3018
+RUN apk add --no-cache git \
+    && npm install
+
 FROM node:11.1-alpine
 
-RUN apk add --no-cache --virtual .build_deps git \
-    && npm install --global speccy \
-    && apk del .build_deps
+COPY --from=builder /opt/speccy/ /opt/speccy/
+
+RUN ln -s /opt/speccy/speccy.js /usr/local/bin/speccy
 
 WORKDIR /project
 
+EXPOSE 5000
 ENTRYPOINT ["speccy"]
 CMD ["-h"]