Docker multistage

Author: tzyian

README.md

@@ -1,8 +1,16 @@
 [![Review Assignment Due Date](https://classroom.github.com/assets/deadline-readme-button-22041afd0340ce965d47ae6ef1cefeee28c7c493a6346c4f15d667ab976d596c.svg)](https://classroom.github.com/a/bzPrOe11)
+
 # CS3219 Project (PeerPrep) - AY2425S1
+
 ## Group: G14
 
-### Note: 
-- You can choose to develop individual microservices within separate folders within this repository **OR** use individual repositories (all public) for each microservice. 
-- In the latter scenario, you should enable sub-modules on this GitHub classroom repository to manage the development/deployment **AND** add your mentor to the individual repositories as a collaborator. 
-- The teaching team should be given access to the repositories as we may require viewing the history of the repository in case of any disputes or disagreements. 
+### Note:
+
+- You can choose to develop individual microservices within separate folders within this repository **OR** use
+  individual repositories (all public) for each microservice.
+- In the latter scenario, you should enable sub-modules on this GitHub classroom repository to manage the
+  development/deployment **AND** add your mentor to the individual repositories as a collaborator.
+- The teaching team should be given access to the repositories as we may require viewing the history of the repository
+  in case of any disputes or disagreements.
+
+Run `docker compose up --build`

backend/Dockerfile

@@ -1,29 +1,95 @@
 # syntax=docker/dockerfile:1
 
-FROM golang:1.23
+# Comments are provided throughout this file to help you get started.
+# If you need more help, visit the Dockerfile reference guide at
+# https://docs.docker.com/go/dockerfile-reference/
 
-# Set destination for COPY
-WORKDIR /backend
+# Want to help us make this template better? Share your feedback here: https://forms.gle/ybq9Krt8jtBL3iCk7
 
-# Download Go modules
-# TODO: don't include the .env file in the COPY
-# TODO: multistage build
-COPY go.mod go.sum ./
-RUN go mod download
+################################################################################
+# Create a stage for building the application.
+ARG GO_VERSION=1.23
+FROM golang:${GO_VERSION} AS build
+WORKDIR /src
 
-# Copy the source code. Note the slash at the end, as explained in
-# https://docs.docker.com/reference/dockerfile/#copy
-COPY . .
+# Download dependencies as a separate step to take advantage of Docker's caching.
+# Leverage a cache mount to /go/pkg/mod/ to speed up subsequent builds.
+# Leverage bind mounts to go.sum and go.mod to avoid having to copy them into
+# the container.
+RUN --mount=type=cache,target=/go/pkg/mod/ \
+    --mount=type=bind,source=go.sum,target=go.sum \
+    --mount=type=bind,source=go.mod,target=go.mod \
+    go mod download -x
 
-# Build
-RUN CGO_ENABLED=0 GOOS=linux go build -o /backend/app
+# This is the architecture you're building for, which is passed in by the builder.
+# Placing it here allows the previous steps to be cached across architectures.
+ARG TARGETARCH=amd64
+
+# Build the application.
+# Leverage a cache mount to /go/pkg/mod/ to speed up subsequent builds.
+# Leverage a bind mount to the current directory to avoid having to copy the
+# source code into the container.
+RUN --mount=type=cache,target=/go/pkg/mod/ \
+    --mount=type=bind,target=. \
+    CGO_ENABLED=0 GOARCH=$TARGETARCH go build -o /bin/server .
+
+
+FROM build AS dev
+
+
+COPY --from=build /bin/server /bin/server
 
-# Optional:
-# To bind to a TCP port, runtime parameters must be supplied to the docker command.
-# But we can document in the Dockerfile what ports
-# the application is going to listen on by default.
-# https://docs.docker.com/reference/dockerfile/#expose
 EXPOSE 9090
 
 # Run
-CMD ["/backend/app"]
+CMD ["/bin/server"]
+
+
+################################################################################
+# Create a new stage for running the application that contains the minimal
+# runtime dependencies for the application. This often uses a different base
+# image from the build stage where the necessary files are copied from the build
+# stage.
+#
+# The example below uses the alpine image as the foundation for running the app.
+# By specifying the "latest" tag, it will also use whatever happens to be the
+# most recent version of that image when you build your Dockerfile. If
+# reproducability is important, consider using a versioned tag
+# (e.g., alpine:3.17.2) or SHA (e.g., alpine@sha256:c41ab5c992deb4fe7e5da09f67a8804a46bd0592bfdf0b1847dde0e0889d2bff).
+FROM alpine:latest AS final
+
+# Install any runtime dependencies that are needed to run your application.
+# Leverage a cache mount to /var/cache/apk/ to speed up subsequent builds.
+RUN --mount=type=cache,target=/var/cache/apk \
+    apk --update add \
+        ca-certificates \
+        tzdata \
+        && \
+        update-ca-certificates
+
+# Create a non-privileged user that the app will run under.
+# See https://docs.docker.com/go/dockerfile-user-best-practices/
+ARG UID=10001
+RUN adduser \
+    --disabled-password \
+    --gecos "" \
+    --home "/nonexistent" \
+    --shell "/sbin/nologin" \
+    --no-create-home \
+    --uid "${UID}" \
+    appuser
+USER appuser
+
+# Copy the executable from the "build" stage.
+COPY --from=build /bin/server /bin/
+
+# Expose the port that the application listens on.
+EXPOSE 9090
+
+
+ENV MONGODB_URI="mongodb+srv://nxtms3:[email protected]/?retryWrites=true&w=majority&appName=questions"
+ENV PORT=":9090"
+ENV CORS_ORIGIN="http://host.docker.internal:3000"
+
+# What the container should run when it is started.
+ENTRYPOINT [ "/bin/server" ]

backend/database/initialise_database.go

@@ -12,11 +12,12 @@ import (
 )
 
 func InitialiseDB() (*mongo.Client, error) {
-	// Load environment variables
-	err := godotenv.Load(".env")
 
-	if err != nil {
-		log.Fatal("Error loading environment variables: " + err.Error())
+	if os.Getenv("ENV") == "" {
+		err := godotenv.Load(".env")
+		if err != nil {
+			log.Fatal("Error loading environment variables: " + err.Error())
+		}
 	}
 
 	mongoURI := os.Getenv("MONGODB_URI")

backend/go.mod

@@ -2,8 +2,6 @@ module peerprep
 
 go 1.23
 
-require github.com/joho/godotenv v1.5.1 // indirect  -allows to load environment variables from a .env file instead of hardcoding them in the code
-
 require (
 	github.com/bytedance/sonic v1.11.6 // indirect
 	github.com/bytedance/sonic/loader v0.1.1 // indirect
@@ -46,6 +44,7 @@ require (
 
 require (
 	github.com/gin-contrib/cors v1.7.2
+	github.com/joho/godotenv v1.5.1
 	github.com/microcosm-cc/bluemonday v1.0.27
 )
 

backend/main.go

@@ -21,9 +21,12 @@ import (
 func main() {
 	//initialise logger file and directory if they do not exist
 
-	err := godotenv.Load(".env")
-	if err != nil {
-		log.Fatal("Error loading environment variables: " + err.Error())
+	// In Docker, the godotenv is not needed as the environment variables are set in the Dockerfile
+	if os.Getenv("ENV") == "" {
+		err := godotenv.Load(".env")
+		if err != nil {
+			log.Fatal("Error loading environment variables: " + err.Error())
+		}
 	}
 
 	ORIGIN := os.Getenv("CORS_ORIGIN")
@@ -39,19 +42,24 @@ func main() {
 
 	logDirectory := "./log"
 
-	if err := os.MkdirAll(logDirectory, 0755); err != nil {
-		logger.Log.Error("Failed to create log directory: " + err.Error())
-	}
-
-	logFile, err := os.OpenFile("./log/question_api.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
+	if os.Getenv("ENV") != "prod" {
+		if err := os.MkdirAll(logDirectory, 0755); err != nil {
+			logger.Log.Error("Failed to create log directory: " + err.Error())
+		}
+		logFile, err := os.OpenFile(
+			"./log/question_api.log",
+			os.O_CREATE|os.O_WRONLY|os.O_APPEND,
+			0666,
+		)
 
-	if err != nil {
-		logger.Log.Warn("Failed to log to file, using default stderr")
-	}
+		if err != nil {
+			logger.Log.Warn("Failed to log to file, using default stderr")
+		}
 
-	defer logFile.Close()
+		defer logFile.Close()
 
-	logger.Log.Out = logFile
+		logger.Log.Out = logFile
+	}
 
 	//initialise the database and handle errors
 	server, err := apidatabase.InitialiseDB()
@@ -63,7 +71,7 @@ func main() {
 	//create a new instance of the questionDB
 	questionDB := apidatabase.NewQuestionDB(server)
 
-	f, _ := os.Create("log/gin.log")
+	f, _ := os.Create("./log/gin.log")
 	gin.DefaultWriter = io.MultiWriter(f, os.Stdout)
 
 	router := gin.Default()

compose.yaml

@@ -1,49 +1,126 @@
+x-common-environment:
+  environment:
+    - ENV=${ENV:-dev}
+
 services:
-  peerprep:
-    build: peerprep
+  peerprep-dev:
+    #    profiles:
+    #      - [ dev ]
+    depends_on:
+      - user-service-dev
+      - backend-dev
+    build:
+      context: peerprep
+      target: dev
     env_file:
       - peerprep/.env
+    environment:
+      - ENV=${ENV:-dev}
+    volumes:
+      - ./peerprep:/frontend
     ports:
-      - "3000:3000"
-    extra_hosts:
-      - "host.docker.internal:host-gateway"
-
+      - "${PEERPREP_PORT:-3000}:3000"
+    #    extra_hosts:
+    #      - "host.docker.internal:host-gateway"
+    networks:
+      - backend
+      - user-service
+      ####### Dockerfile Node is distroless, no curl
+      #    healthcheck:
+      #      test: [ "CMD", "curl", "-f", "http://localhost:3000/" ]
+    restart: on-failure
     develop:
       watch:
         - action: sync
           path: peerprep
           target: /frontend
 
-  user-service:
-    build: user-service
-    volumes:
-      - /user-service/node_modules
+
+  user-service-dev:
+    #    profiles:
+    #      - [ dev ]
+    build:
+      context: user-service
+      target: dev
     env_file:
       - user-service/.env
-    extra_hosts:
-      - "host.docker.internal:host-gateway"
+    environment:
+      - ENV=${ENV:-PROD}
+    volumes:
+      - ./user-service:/user-service
     ports:
-      - "3001:3001"
+      - "${USER_SERVICE_PORT:-3001}:3001"
+    networks:
+      - user-service
+    #    extra_hosts:
+    #      - "host.docker.internal:host-gateway"
+    #    healthcheck:
+    #      test: [ "CMD", "curl", "-f", "http://localhost:3001/" ]
+    restart: on-failure
     develop:
       watch:
-        - action: rebuild
+        - action: sync
           path: user-service
           target: /user-service
 
+  #  user-service-prod:
+  #    extends:
+  #      service: user-service-dev
+  #    profiles:
+  #      - [ prod ]
+  #    environment:
+  #      - ENV=prod
+  #    build:
+  #      target: final
 
-  backend:
-    build: backend
+  backend-dev:
+    #    profiles:
+    #      - [ dev ]
+    build:
+      context: backend
+      target: dev
     env_file:
       - backend/.env
+    environment:
+      - ENV=${ENV:-dev}
+
+    volumes:
+      - logs:/log
+      - ./backend:/src
     ports:
-      - "9090:9090"
+      - "${BACKEND_PORT:-9090}:9090"
+    networks:
+      - backend
+    healthcheck:
+      test: [ "CMD", "curl", "-f", "http://localhost:9090/health" ]
+    restart: on-failure
     develop:
       watch:
         - action: rebuild
           path: backend
           target: backend/app
 
+
+#    backend-prod:
+#      extends:
+#        service: backend-prod
+#      profiles:
+#        - [ prod ]
+#      environment:
+#        - ENV=prod
+#      build:
+#        target: final
+
 #  mongo:
 #    image: "mongo:latest"
 #    ports:
-#      - "27017:27017"
+#      - "27017:27017"
+
+networks:
+  backend:
+    driver: bridge
+  user-service:
+    driver: bridge
+
+volumes:
+  logs: