Enhance service configuration

.env

@@ -0,0 +1,3 @@
+BUCKET=sample_bucket
+PORT=55555
+DB_PATH=sample_db.db

Dockerfile

@@ -0,0 +1,14 @@
+FROM golang:1.21 AS builder
+
+WORKDIR /app
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . .
+RUN go build -o main .
+
+FROM alpine:latest
+
+WORKDIR /app
+COPY --from=builder /app/main .
+EXPOSE 8080
+CMD ["./main"]

README.md

@@ -37,8 +37,20 @@ The RESTful API is described in an OpenAPI 3.0 document found here: ([openapi.js
 Running
 =======
 
-```bash
-usage: ./rest-api-microservice-demo db_path [port] [db_bucket_name]
+**Native**
+```sh
+go run main.go
+```
+
+**Docker**
+```sh
+docker build -t rest-api-microservice-demo .
+docker run -p ${PORT}:${PORT} rest-api-microservice-demo
+```
+
+**Docker Compose**
+```sh
+docker-compose up --build
 ```
 
 Testing

docker-compose.yaml

@@ -0,0 +1,9 @@
+services:
+  go-service:
+    build: .
+    ports:
+      - "${PORT}:${PORT}"
+    environment:
+      - BUCKET=${BUCKET}
+      - PORT=${PORT}
+      - DB_PATH=${DB_PATH}

main.go

@@ -9,60 +9,40 @@ import (
 	"github.com/brandonto/rest-api-microservice-demo/db"
 )
 
-const defaultDbBucketName = "DetailedMessageBucket"
-const defaultPort = uint64(55555)
-
-func main() {
-	// Outputs usage if number of arguments are off
-	//
-	if len(os.Args) > 4 || len(os.Args) < 2 {
-		fmt.Println("usage: " + os.Args[0] + " db_path [port] [db_bucket_name]")
-		return
-	}
-
-	// First argument is the filepath of the database
-	//
-	dbFile := os.Args[1]
-
-	// Second (optional) argument is the the port number
-	//
-	port := defaultPort
-	if len(os.Args) > 2 {
-		// Some sanity check for the port argument before using
-		//
-		var err error
-		port, err = strconv.ParseUint(os.Args[2], 10, 64)
-		if err != nil {
-			fmt.Println("port argument must be an unsigned integer")
-			return
-		}
+const (
+	envDbBucketName = "BUCKET"
+	envPortName     = "PORT"
+	dbPathName      = "DB_PATH"
+)
 
-		if port < uint64(49152) || port > uint64(65535) {
-			fmt.Println("port argument must be a value between 49152–65535")
-			return
-		}
+func getConfig() core.Config {
+	envPort, cP := os.LookupEnv(envPortName)
+	bucket, cB := os.LookupEnv(envDbBucketName)
+	dbFile, cD := os.LookupEnv(dbPathName)
+	if !cP || !cB || !cD {
+		fmt.Errorf("enviroment variables: [%s, %s, %s] are required...", envDbBucketName, envPortName, dbPathName)
 	}
-
-	// Third (optional) argument is the the bucket name
-	//
-	dbBucketName := defaultDbBucketName
-	if len(os.Args) > 3 {
-		dbBucketName = os.Args[3]
+	port, err := strconv.ParseUint(envPort, 10, 64)
+	if err != nil {
+		fmt.Errorf("PORT environment variable must be an unsigned integer, value was: %s", envPort)
 	}
 
-	// Configure and run the application
-	//
-	dbCfg := db.Config{
-		FilePath:   dbFile,
-		BucketName: dbBucketName,
+	if port < uint64(49152) || port > uint64(65535) {
+		fmt.Errorf("PORT environment variable must be a value between 49152–65535, value was: %s", envPort)
 	}
 
 	coreCfg := core.Config{
-		DbCfg:        dbCfg,
+		DbCfg: db.Config{
+			FilePath:   dbFile,
+			BucketName: bucket,
+		},
 		Port:         port,
 		EnableLogger: true,
 		Standalone:   true,
 	}
+	return coreCfg
+}
 
-	core.Run(coreCfg)
+func main() {
+	core.Run(getConfig())
 }

swagger.yaml

@@ -0,0 +1,106 @@
+openapi: 3.0.3
+info:
+  title: REST API Microservice Demo
+  description: A simple REST API microservice.
+  version: 1.0.0
+servers:
+  - url: http://localhost:8080
+    description: Local server
+
+paths:
+  /messages:
+    get:
+      summary: Get all messages
+      operationId: getMessages
+      responses:
+        '200':
+          description: A list of messages
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Message'
+    post:
+      summary: Create a new message
+      operationId: createMessage
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/Message'
+      responses:
+        '201':
+          description: Message created
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/DetailedMessage'
+
+  /messages/{messageId}:
+    get:
+      summary: Get a message by ID
+      operationId: getMessageById
+      parameters:
+        - name: messageId
+          in: path
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: A message with metadata
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/DetailedMessage'
+        '404':
+          description: Message not found
+    delete:
+      summary: Delete a message by ID
+      operationId: deleteMessage
+      parameters:
+        - name: messageId
+          in: path
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '204':
+          description: Message deleted
+        '404':
+          description: Message not found
+
+components:
+  schemas:
+    Message:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        payload:
+          type: string
+      required:
+        - id
+        - payload
+
+    MessageMetadata:
+      type: object
+      properties:
+        palindrome:
+          type: boolean
+
+    DetailedMessage:
+      type: object
+      properties:
+        message:
+          $ref: '#/components/schemas/Message'
+        metadata:
+          $ref: '#/components/schemas/MessageMetadata'
+      required:
+        - message
+        - metadata