gin-lambda

running golang using gin framework in AWS Lambda & API Gateway

Sample code

see the main.go in master branch.

package main
import (
    "log"
    "net/http"
    "os"
    "github.com/apex/gateway"
    "github.com/gin-gonic/gin"
)
func helloHandler(c *gin.Context) {
    name := c.Param("name")
    c.String(http.StatusOK, "Hello %s", name)
}
func welcomeHandler(c *gin.Context) {
    c.String(http.StatusOK, "Hello World from Go")
}
func rootHandler(c *gin.Context) {
    c.JSON(http.StatusOK, gin.H{
        "text": "Welcome to gin lambda server.",
    })
}
func routerEngine() *gin.Engine {
    // set server mode
    gin.SetMode(gin.DebugMode)
    r := gin.New()
    // Global middleware
    r.Use(gin.Logger())
    r.Use(gin.Recovery())
    r.GET("/welcome", welcomeHandler)
    r.GET("/user/:name", helloHandler)
    r.GET("/", rootHandler)
    return r
}
func main() {
    addr := ":" + os.Getenv("PORT")
    log.Fatal(gateway.ListenAndServe(addr, routerEngine()))
}

Build and Upload

Build binary

$ GOOS=linux go build -o main .
$ zip deployment.zip main

Upload the deployment.zip to AWS Lambda using drone-lambda command.

$ AWS_ACCESS_KEY_ID=xxxx \ 
  AWS_SECRET_ACCESS_KEY=xxx \
  drone-lambda --region ap-southeast-1 \
  --function-name function_name \
  --zip-file deployment.zip

Output log:

{
  CodeSha256: "r/I7yg9tX9MWPsPH337Xk5MIF1dVgkDCFhOrmAYe7hc=",
  CodeSize: 4334079,
  Description: "",
  Environment: {
    Variables: {
      PORT: "8080"
    }
  },
  FunctionArn: "arn:aws:lambda:ap-southeast-1:xxxxxxx:function:gin:7",
  FunctionName: "gin",
  Handler: "main",
  LastModified: "2018-01-21T06:21:28.395+0000",
  MemorySize: 128,
  Role: "arn:aws:iam::xxxxxxx:role/service-role/test",
  Runtime: "go1.x",
  Timeout: 3,
  TracingConfig: {
    Mode: "PassThrough"
  },
  Version: "7",
  VpcConfig: {
    SecurityGroupIds: [],
    SubnetIds: []
  }
}

AWS Policy

Add the following AWS policy if you want to integrate with CI/CD tools like Jenkins, GitLab Ci or Drone.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:PutObject",
        "iam:ListRoles",
        "lambda:UpdateFunctionCode",
        "lambda:CreateFunction"
      ],
      "Resource": "*"
    }
  ]
}

Benchmark

Memory: 128 MB, Latencies: 6.091282008s

$ vegeta attack -rate=1024 -duration=10s -targets=target2.txt | tee results.bin | vegeta report
Requests      [total, rate]            10240, 1024.10
Duration      [total, attack, wait]    20.335101947s, 9.999018014s, 10.336083933s
Latencies     [mean, 50, 95, 99, max]  6.091282008s, 4.893951645s, 14.508009942s, 17.11847442s, 20.128384389s
Bytes In      [total, mean]            143360, 14.00
Bytes Out     [total, mean]            0, 0.00
Success       [ratio]                  100.00%
Status Codes  [code:count]             200:10240

Memory: 512 MB, Latencies: 1.491340336s

$ vegeta attack -rate=1024 -duration=10s -targets=target2.txt | tee results.bin | vegeta report
Requests      [total, rate]            10240, 1024.10
Duration      [total, attack, wait]    11.989730554s, 9.999012371s, 1.990718183s
Latencies     [mean, 50, 95, 99, max]  1.491340336s, 1.114643849s, 4.112241113s, 6.087949237s, 10.107294516s
Bytes In      [total, mean]            143360, 14.00
Bytes Out     [total, mean]            0, 0.00
Success       [ratio]                  100.00%
Status Codes  [code:count]             200:10240