Feat/add cron job (#178)

* feat: add lambda

* feat: add cron job entry point

* feat: deploy to lambda using github actions

---------

Co-authored-by: Eyo Chen <eyo.chen@amazingtalker.com>

.github/workflows/cd-lambda.yml

@@ -0,0 +1,61 @@
+name: Let's Deploy Cron Lambda
+
+on:
+  workflow_run:
+    workflows: ["Let's Go CI"]
+    types:
+      - completed
+    branches: [main]
+
+jobs:
+  deploy-lambda:
+    if: |
+      github.event.workflow_run.conclusion == 'success' &&
+      github.event.workflow_run.head_branch == 'main'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout Source
+        uses: actions/checkout@v4
+
+      - name: Get changed files
+        id: changed-files
+        uses: tj-actions/changed-files@v42
+
+      - name: Check if relevant files changed
+        id: check-changes
+        run: |
+          RELEVANT=false
+          for file in ${{ steps.changed-files.outputs.all_changed_files }}; do
+            if [[ $file == cmd/cron/* ]]; then
+              RELEVANT=true
+              break
+            fi
+          done
+          if [ "$RELEVANT" = "false" ]; then
+            echo "No relevant files changed, skipping deployment"
+            exit 78  # Special exit code that GitHub Actions recognizes as neutral
+          fi
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.22.x'
+
+      - name: Configure AWS Credentials
+        uses: aws-actions/configure-aws-credentials@v4
+        with:
+          aws-access-key-id: ${{ secrets.AWS_KEY }}
+          aws-secret-access-key: ${{ secrets.AWS_SECRET }}
+          aws-region: ${{ secrets.AWS_REGION }}
+
+      - name: Build Lambda Function
+        run: |
+          GOOS=linux GOARCH=amd64 go build -o bootstrap cmd/cron/main.go
+          zip go-lambda.zip bootstrap
+
+      - name: Deploy to Lambda
+        run: |
+          aws lambda update-function-code \
+            --function-name ${{ secrets.AWS_LAMBDA_FUNCTION_NAME }} \
+            --zip-file fileb://go-lambda.zip

cmd/cron/main.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/aws/aws-lambda-go/lambda"
+	adapter "github.com/eyo-chen/expense-tracker-go/internal/adapter"
+	"github.com/eyo-chen/expense-tracker-go/internal/usecase/monthlytrans"
+	"github.com/eyo-chen/expense-tracker-go/pkg/logger"
+	_ "github.com/go-sql-driver/mysql"
+)
+
+func main() {
+	lambda.Start(handleRequest)
+}
+
+func handleRequest(ctx context.Context) error {
+	logger.Register()
+
+	logger.Info("Connecting to database...")
+	mysqlDB, err := newMysqlDB()
+	if err != nil {
+		logger.Error("Unable to connect to mysql database", "error", err)
+		return err
+	}
+	defer mysqlDB.Close()
+
+	// Setup adapter and usecase
+	adapter := adapter.New(mysqlDB, nil, nil, nil, "")
+	monthlyTransUC := monthlytrans.New(adapter.MonthlyTrans, adapter.Transaction)
+
+	// Execute monthly transaction aggregation for previous month
+	previousMonth := time.Now().AddDate(0, -1, 0)
+	if err := monthlyTransUC.Create(ctx, previousMonth); err != nil {
+		logger.Error("Failed to create monthly transaction aggregation", "error", err)
+		return err
+	}
+
+	logger.Info("Successfully created monthly transaction aggregation", "month", previousMonth.Format(time.DateOnly))
+	return nil
+}
+
+func newMysqlDB() (*sql.DB, error) {
+	config := map[string]string{
+		"host":     os.Getenv("DB_HOST"),
+		"port":     os.Getenv("DB_PORT"),
+		"name":     os.Getenv("DB_NAME"),
+		"user":     os.Getenv("DB_USER"),
+		"password": os.Getenv("DB_PASSWORD"),
+	}
+
+	dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?parseTime=true", config["user"], config["password"], config["host"], config["port"], config["name"])
+	db, err := sql.Open("mysql", dsn)
+	if err != nil {
+		return nil, err
+	}
+
+	if err = db.Ping(); err != nil {
+		return nil, err
+	}
+
+	return db, nil
+}

go.mod

@@ -22,6 +22,7 @@ require (
 	github.com/Azure/go-ansiterm v0.0.0-20230124172434-306776ec8161 // indirect
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5 // indirect
+	github.com/aws/aws-lambda-go v1.47.0 // indirect
 	github.com/aws/aws-sdk-go-v2 v1.31.0 // indirect
 	github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.6.5 // indirect
 	github.com/aws/aws-sdk-go-v2/config v1.27.36 // indirect

go.sum

@@ -8,6 +8,8 @@ github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERo
 github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA8Ipt1oGCvU=
 github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5 h1:TngWCqHvy9oXAN6lEVMRuU21PR1EtLVZJmdB18Gu3Rw=
 github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5/go.mod h1:lmUJ/7eu/Q8D7ML55dXQrVaamCz2vxCfdQBasLZfHKk=
+github.com/aws/aws-lambda-go v1.47.0 h1:0H8s0vumYx/YKs4sE7YM0ktwL2eWse+kfopsRI1sXVI=
+github.com/aws/aws-lambda-go v1.47.0/go.mod h1:dpMpZgvWx5vuQJfBt0zqBha60q7Dd7RfgJv23DymV8A=
 github.com/aws/aws-sdk-go-v2 v1.30.5 h1:mWSRTwQAb0aLE17dSzztCVJWI9+cRMgqebndjwDyK0g=
 github.com/aws/aws-sdk-go-v2 v1.30.5/go.mod h1:CT+ZPWXbYrci8chcARI3OmI/qgd+f6WtuLOoaIA8PR0=
 github.com/aws/aws-sdk-go-v2 v1.31.0 h1:3V05LbxTSItI5kUqNwhJrrrY1BAXxXt0sN0l72QmG5U=