Running a Go application on AWS Lambda is easier than ever, once you figure out how to configure Lambda, API Gateway and 10 or other "serverless" services to support the Go functions.
This is a boilerplate app with all the AWS pieces configured correctly and explained in depth. See the docs folder for detailed guides about functions, tracing, security, automation and more with AWS and Go.
With this foundation you can skip over all the undifferentiated setup, and focus entirely on your Go code.
Functions-as-a-Service (FaaS) like AWS Lambda are one of the latest advances in cloud Infrastructure-as-a-Service (IaaS). Go is particularly well-suited to run in Lambda due to its speed, size and cross-compiler. Check out the Intro to Go Functions-as-a-Service and Lambda doc for more explanation.
For a long time, Go in Lambda was only possible through hacks -- execution shims, 3rd party frameworks and middleware, and little dev/prod parity. But in January 2018, AWS launched official Go support for Lambda and Go released v1.10 paving the clearest path yet for us Gophers.
This project demonstrates a simple and clean foundation for Go in Lambda. You can clone and deploy it with a few commands to get a feel for the stack. Or you can fork and rework it to turn it into your own web app.
It demonstrates:
| Component | Via | Config, Code |
|---|---|---|
| HTTP functions | Lambda, API Gateway | 💾 |
| Worker functions (one-off and periodic) | Lambda, Invoke API, CloudWatch Events | 💾 |
| Development, packaging and deployment | make, go, aws-sam-cli, CloudFormation | ⚙️ |
| Per-function environment and policies | Lambda, IAM | ⚙️ |
| Custom domains | CloudFront, ACM | ⚙️ |
| Static web content | S3, CloudFront, ACM | ⚙️ |
| Static web security with Google OAuth 2.0 | CloudFront, Lambda@Edge, SSM Parameters | 💾 |
| Function security with CORS and JWT | API Gateway, jwt-go | 💾 |
| Function traces and logs | CloudWatch Logs, X-Ray, AWS SDKs for Go | 💾 |
| Notifications | SNS | 💾 |
| Databases and encryption at rest | DynamoDB, KMS | 💾 |
| Testing with mock AWS clients | Go interfaces, aws-sdk-go | 💾 |
What's remarkable is how little work is required to get all functionality for our app. We don't need a framework, platform-as-a-service, or even any 3rd party software-as-a-service. And no, we don't need servers. By standing on the shoulders of Go and AWS, all the undifferentiated heavy lifting is managed for us.
We just need an expert CloudFormation config file and a simple Makefile, then we can focus entirely on writing Go functions.
This project uses :
Install the CLI tools and Docker CE
$ brew install awscli go node python@2 watchexec
$ pip2 install aws-sam-cli
$ open https://store.docker.com/search?type=edition&offering=communityWe may want to upgrade existing tools...
$ brew upgrade awscli go node python@2 watchexec
$ pip2 install --upgrade aws-sam-cliWe may want to double check the installed versions...
$ aws --version
aws-cli/1.16.20 Python/3.7.0 Darwin/17.7.0 botocore/1.12.10
$ sam --version
SAM CLI, version 0.6.0
$ docker version
Client:
Version: 18.06.1-ce
API version: 1.38
Go version: go1.10.3
Git commit: e68fc7a
Built: Tue Aug 21 17:21:31 2018
OS/Arch: darwin/amd64
Experimental: false
Server:
Engine:
Version: 18.06.1-ce
API version: 1.38 (minimum version 1.12)
Go version: go1.10.3
Git commit: e68fc7a
Built: Tue Aug 21 17:29:02 2018
OS/Arch: linux/amd64
Experimental: true
$ go version
go version go1.11.1 darwin/amd64
$ watchexec --version
watchexec 1.9.2We may also want to configure the AWS CLI with IAM keys to develop and deploy our application...
Follow the Creating an IAM User in Your AWS Account doc to create a IAM user with programmatic access. Call the user gofaas-admin and attach the "Administrator Access" policy for now.
Then configure the CLI. Here we are creating a new profile that we can switch to with export AWS_PROFILE=gofaas. This will help us isolate our experiments from other AWS work.
Configure an AWS profile with keys and switch to the profile:
$ aws configure --profile gofaas
AWS Access Key ID [None]: AKIA................
AWS Secret Access Key [None]: PQN4CWZXXbJEgnrom2fP0Z+z................
Default region name [None]: us-east-1
Default output format [None]: json
$ export AWS_PROFILE=gofaas
$ aws iam get-user
{
"User": {
"Path": "/",
"UserName": "gofaas-admin",
"UserId": "AIDAJA44LJEOECDPZ3S5U",
"Arn": "arn:aws:iam::572007530218:user/gofaas-admin",
"CreateDate": "2018-02-16T16:17:24Z"
}
}We start by getting and testing the github.com/nzoschke/gofaas.
$ git clone https://github.com/nzoschke/gofaas.git ~/dev/gofaas
$ cd ~/dev/gofaas
$ make test
go test -v ./...
go: finding github.com/aws/aws-xray-sdk-go v1.0.0-rc.8
go: finding github.com/aws/aws-lambda-go v1.6.0
go: finding github.com/aws/aws-sdk-go v1.15.49
...
=== RUN TestUserCreate
--- PASS: TestUserCreate (0.00s)
...
ok github.com/nzoschke/gofaas 0.014s
PASSThis gives us confidence in our Go environment.
We can then build the app and start a development server:
$ make dev
cd ./handlers/dashboard && GOOS=linux go build...
2018/02/25 08:03:12 Connected to Docker 1.35
2018/02/16 07:40:32 Fetching lambci/lambda:go1.x image for go1.x runtime...
Mounting handler (go1.x) at http://127.0.0.1:3000/users/{id} [DELETE]
Mounting handler (go1.x) at http://127.0.0.1:3000/users/{id} [PUT]
Mounting handler (go1.x) at http://127.0.0.1:3000/users/{id} [GET]
Mounting handler (go1.x) at http://127.0.0.1:3000/ [GET]
Mounting handler (go1.x) at http://127.0.0.1:3000/users [POST]Now we can access our HTTP functions on port 3000:
$ curl http://localhost:3000
<html><body><h1>gofaas dashboard</h1></body></html>We can also invoke a function directly:
$ echo '{}' | sam local invoke WorkerFunction
...
START RequestId: 36d6d40e-0d4b-168c-63d5-76b25f543d21 Version: $LATEST
2018/02/25 16:05:21 Worker Event: {SourceIP: TimeEnd:0001-01-01 00:00:00 +0000 UTC TimeStart:0001-01-01 00:00:00 +0000 UTC}
END RequestId: 36d6d40e-0d4b-168c-63d5-76b25f543d21
REPORT RequestId: 36d6d40e-0d4b-168c-63d5-76b25f543d21 Duration: 681.67 ms Billed Duration: 700 ms Memory Size: 128 MB Max Memory Used: 14 MB
Note: if you see No AWS credentials found. Missing credentials may lead to slow startup..., review aws configure list and your AWS_PROFILE env var.
This gives us confidence in our development environment.
Now we can package and deploy the app:
$ make deploy
make_bucket: pkgs-572007530218-us-east-1
Uploading to 59d2ea5b6bdf38fcbcf62236f4c26f21 3018471 / 3018471.0 (100.00%)
Waiting for changeset to be created
Waiting for stack create/update to complete
Successfully created/updated stack - gofaas
ApiUrl https://x19vpdk568.execute-api.us-east-1.amazonaws.com/ProdNow we can access our HTTP functions on AWS:
$ curl https://x19vpdk568.execute-api.us-east-1.amazonaws.com/Prod
<html><body><h1>gofaas dashboard</h1></body></html>We can also invoke a function directly:
$ aws lambda invoke --function-name gofaas-WorkerFunction --log-type Tail --output text --query 'LogResult' out.log | base64 -D
START RequestId: 0bb47628-1718-11e8-ad73-c58e72b8826c Version: $LATEST
2018/02/21 15:01:07 Worker Event: {SourceIP: TimeEnd:0001-01-01 00:00:00 +0000 UTC TimeStart:0001-01-01 00:00:00 +0000 UTC}
END RequestId: 0bb47628-1718-11e8-ad73-c58e72b8826c
REPORT RequestId: 0bb47628-1718-11e8-ad73-c58e72b8826c Duration: 11.11 ms Billed Duration: 100 ms Memory Size: 128 MB Max Memory Used: 41 MBLook at that speedy 11 ms duration! Go is faster than the minimum billing duration of 100 ms.
This gives us confidence in our production environment.
If we want to work on the worker or database functions locally, we need to give the functions environment variables with pointers to DynamoDB, KMS and S3. Open up env.json and set BUCKET, etc. with the ids of the resources we just created on deploy:
$ aws cloudformation describe-stack-resources --output text --stack-name gofaas \
--query 'StackResources[*].{Name:LogicalResourceId,Id:PhysicalResourceId,Type:ResourceType}' | \
grep 'Bucket\|Key\|UsersTable'
gofaas-bucket-aykdokk6aek8 Bucket AWS::S3::Bucket
8eb8e209-51fb-41fa-adfe-1ec401667df4 Key AWS::KMS::Key
gofaas-UsersTable-1CYAQH3HHHRGW UsersTable AWS::DynamoDB::TableWe can verify the app functionality by creating an isolated testing stack, testing all the endpoints, then deleting the stack. The ci.sh script automates this:
$ ./ci.sh
aws cloudformation package ...
aws cloudformation deploy ...
...
<title>My first gofaas/Vue app</title>
"username": "test"
{"ExecutedVersion":null,"FunctionError":null,"LogResult":null,"Payload":"","StatusCode":202}
...
✅ SUCCESS!Check out the docs folder where each component is explained in more detail.
Find a bug or see a way to improve the project? Open an issue.
Apache 2.0 © 2018 Noah Zoschke