test: Add elm-format + elm-make job to ci

This runs elm-format and elm-make inside a docker container which servs
the Elm environment.

Related to issue #671

.travis.yml

@@ -1,8 +1,16 @@
 sudo: false
 language: go
 
+services:
+  - docker
+
 go:
 - 1.7.3
 
+before_install:
+- docker build -t elm-env ui/.
+
 script:
 - make
+- docker run --rm -t -v "$(pwd):/app" -w /app/ui/app elm-env elm-format --validate src/
+- docker run --rm -t -v "$(pwd):/app" -w /app/ui/app elm-env elm-make --yes src/Main.elm --output /dev/null

ui/Dockerfile

@@ -0,0 +1,11 @@
+FROM node:latest
+
+ENV ELM_FORMAT_VERSION 0.6.0-alpha
+ENV ELM_VERSION 0.18
+
+RUN npm install -g elm@0.18.0
+
+RUN wget https://github.com/avh4/elm-format/releases/download/${ELM_FORMAT_VERSION}/elm-format-${ELM_VERSION}-${ELM_FORMAT_VERSION}-linux-x64.tgz -O "elm-format"  && \
+    tar -xvzf elm-format && \
+    mv elm-format /usr/local/bin/elm-format && \
+    chmod +x /usr/local/bin/elm-format

ui/app/src/Silences/Decoders.elm

@@ -37,10 +37,9 @@ silence =
         |: (field "createdBy" Json.string)
         -- Remove this maybe once the api either disallows empty comments on
         -- creation, or returns an empty string.
-        |:
-            ((Json.maybe (field "comment" Json.string))
+        |: ((Json.maybe (field "comment" Json.string))
                 |> Json.andThen (\x -> Json.succeed <| Maybe.withDefault "" x)
-            )
+           )
         |: (field "startsAt" iso8601Time)
         |: (field "endsAt" iso8601Time)
         |: (field "updatedAt" iso8601Time)

ui/app/src/Views/SilenceForm/Types.elm

@@ -33,9 +33,15 @@ toSilence { createdBy, comment, startsAt, endsAt, matchers } =
             , createdBy = createdBy
             , startsAt = parsedStartsAt
             , endsAt = parsedEndsAt
-            , silencedAlertGroups = Success [] {- ignored -}
-            , updatedAt = 0 {- ignored -}
-            , id = "" {- ignored -}
+
+            {- ignored -}
+            , silencedAlertGroups = Success []
+
+            {- ignored -}
+            , updatedAt = 0
+
+            {- ignored -}
+            , id = ""
             }
         )
         (timeFromString startsAt)