Docker production overrides (#5)

* Add production overrides

* Add config stub

* Stop building after dev stage for dev override

* Fixup ports for production build

* Add entrypoint script to write relevant env vars to file

Author: ivan-c

.env.default

@@ -7,3 +7,6 @@ COMPOSE_PROJECT_NAME=
 
 # docker-compose development overrides; uncomment to enable
 # COMPOSE_FILE=docker-compose.yaml:docker-compose.dev.yaml
+
+# docker-compose production overrides; uncomment to enable
+# COMPOSE_FILE=docker-compose.yaml:docker-compose.prod.yaml

Dockerfile

@@ -1,5 +1,5 @@
 # TODO update to newer version: Active LTS or Current
-FROM node:14
+FROM node:14 as dev
 
 # cache hack (very fragile): initially only copy list of project dependencies
 COPY --chown=node:node package.json package-lock.json /opt/node/
@@ -18,3 +18,17 @@ WORKDIR /opt/node/app
 
 EXPOSE 3000
 CMD ["npm", "start"]
+
+
+FROM dev as node-prod
+ENV NODE_ENV=production
+RUN npm run build
+
+
+FROM nginx as prod
+COPY docker-entrypoint-override.sh /usr/bin/docker-entrypoint-override.sh
+# write environment variables to config file and start
+ENTRYPOINT ["/usr/bin/docker-entrypoint-override.sh", "/docker-entrypoint.sh"]
+CMD ["nginx","-g","daemon off;"]
+
+COPY --from=node-prod /opt/node/app/build /usr/share/nginx/html

docker-compose.dev.yaml

@@ -3,6 +3,9 @@
 version: "3.4"
 services:
   frontend:
+    build:
+      # stop building Dockerfile after dev stage
+      target: dev
     volumes:
       # mount code directory into container to allow hot-reloading
       - ./:/opt/node/app

docker-compose.prod.yaml

@@ -0,0 +1,12 @@
+# docker-compose production overrides
+---
+version: "3.4"
+services:
+  frontend:
+    build:
+      target: prod
+    environment:
+      NODE_ENV: production
+    ports:
+      # map container port 80 to $FRONTEND_EXTERNAL_PORT (port 3000 by default) on localhost (127.0.0.1)
+      - 127.0.0.1:${FRONTEND_EXTERNAL_PORT:-3000}:80

docker-entrypoint-override.sh

@@ -0,0 +1,40 @@
+#!/bin/sh
+set -eu
+
+repo_path="$(cd "$(dirname "$0")" && pwd)"
+cmdname="$(basename "$0")"
+
+usage() {
+    cat << USAGE >&2
+Usage:
+    $cmdname command
+
+    Docker entrypoint script
+    Wrapper script that executes docker-related tasks before running given command
+
+USAGE
+    exit 1
+}
+
+if [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
+    usage
+    exit 0
+fi
+
+
+write_env_to_json() {
+    # write project-specific environment variables to app config file
+    local json_file="$1"
+
+    # only write environment variables frontend will read (beginning with "REACT_" or "VUE_")
+    local json_contents="{$(printenv | grep -e REACT_ -e VUE_ | sed 's/^\|$/"/g' | sed 's|=|":"|' | paste -sd, -)}"
+    echo "$json_contents" > "$json_file"
+}
+
+
+write_env_to_json /usr/share/nginx/html/env.json
+
+
+echo $cmdname complete
+echo executing given command $@
+exec "$@"