Add build arg to Heroku Dockerfile

DarthSim · DarthSim · commit 6ce4201bb01d · 2019-06-18T20:49:26.000+06:00
diff --git a/heroku.yml b/heroku.yml
@@ -1,3 +1,5 @@
 build:
+  config:
+    IMGPROXY_TAG: latest
   docker:
     web: heroku/Dockerfile
diff --git a/heroku/Dockerfile b/heroku/Dockerfile
@@ -1,2 +1,4 @@
-FROM darthsim/imgproxy:latest
+ARG IMGPROXY_TAG=latest
+
+FROM darthsim/imgproxy:$IMGPROXY_TAG
 LABEL maintainer="Sergey Alexandrovich <darthsim@gmail.com>"
