* fn: agent MaxRequestSize limit Currently, LimitRequestBody() exists to install a http request body size in http/gin server. For production enviroments, this is expected to be used. However, in agents we may need to verify/enforce these size limits and to be able to assert in case of missing limits is valuable. With this change, operators can define an agent env variable to limit this in addition to installing Gin/Http handler. http.MaxBytesReader is superior in some cases as it sets http headers (Connection: close) to guard against subsequent requests. However, NewClampReadCloser() is superior in other cases, where it can cleanly return an API error for this case alone (http.MaxBytesReader() does not return a clean error type for overflow case, which makes it difficult to use it without peeking into its implementation.) For lb agent, upcoming changes rely on such limits enabled and using gin/http handler (http.MaxBytesReader) makes such checks/safety validations difficult. * fn: read/write clamp code adjustment In case of overflows, opt for simple implementation of a partial write followed by return error.
Quickstart | Tutorials | Docs | API | Operating | Flow | UI
Welcome
Fn is an event-driven, open source, Functions-as-a-Service (FaaS) compute platform that you can run anywhere. Some of its key features:
- Open Source
- Native Docker: use any Docker container as your Function
- Supports all languages
- Run anywhere
- Public, private and hybrid cloud
- Import Lambda functions and run them anywhere
- Easy to use for developers
- Easy to manage for operators
- Written in Go
- Simple yet powerful extensibility
The fastest way to experience Fn is to follow the quickstart below, or you can jump right to our full documentation, API Docs, or hit us up in our Slack Community!
Quickstart
Pre-requisites
- Docker 17.10.0-ce or later installed and running
- A Docker Hub account (Docker Hub) (or other Docker-compliant registry)
- Log Docker into your Docker Hub account:
docker login
Install CLI tool
The command line tool isn't required, but it sure makes things a lot easier. There are a few options to install it:
1. Homebrew - MacOS
If you're on a Mac and use Homebrew, this one is for you:
brew install fn
2. Shell script - Linux and MacOS
This one works on Linux and MacOS (partially on Windows):
curl -LSs https://raw.githubusercontent.com/fnproject/cli/master/install | sh
This will download a shell script and execute it. If the script asks for a password, that is because it invokes sudo.
3. Download the bin - Linux, MacOS and Windows
Head over to our releases and download it.
Run Fn Server
Now fire up an Fn server:
fn start
This will start Fn in single server mode, using an embedded database and message queue. You can find all the configuration options here. If you are on Windows, check here. If you are on a Linux system where the SELinux security policy is set to "Enforcing", such as Oracle Linux 7, check here.
Your First Function
Functions are small but powerful blocks of code that generally do one simple thing. Forget about monoliths when using functions, just focus on the task that you want the function to perform. Our CLI tool will help you get started super quickly.
Create hello world function:
fn init --runtime go hello
This will create a simple function in the directory hello, so let's cd into it:
cd hello
Feel free to check out the files it created or just keep going and look at it later.
# Set your Docker Hub username
export FN_REGISTRY=<DOCKERHUB_USERNAME>
# Run your function locally
fn run
# Deploy your functions to your local Fn server
fn deploy --app myapp --local
Now you can call your function:
curl http://localhost:8080/r/myapp/hello
# or:
fn call myapp /hello
Or in a browser: http://localhost:8080/r/myapp/hello
That's it! You just deployed your first function and called it. Try updating the function code in func.go then deploy it again to see the change.
Learn More
- With our Fn Getting Started Series, quickly create Fn Hello World applications in multiple languages. This is a great Fn place to start!
- Visit Fn tutorials for step by step guides to creating apps with Fn . These tutorials range from introductory to more advanced.
- See our full documentation
- View all of our examples
- View our YouTube Channel
- View our API Docs
- Check out our sub-projects: Flow, UI, FnLB
- For a full presentation with lots of content you can use in your own presentations, see The Fn Project Presentation Master
Get Help
- Ask your question on StackOverflow and tag it with
fn - Join our Slack Community
Get Involved
- Join our Slack Community
- Learn how to contribute
- See issues for issues you can help with
- Join us at one of our Fn Events or even speak at one!
