README.md

Install Fn

Fn is a lightweight Docker-based serverless functions platform you can run on your laptop, server, or cloud. In this installation tutorial we'll walk through installing Fn.

Setting up a working Fn installation involves these three simple steps:

• Ensure you have the necessary prerequisites
• Download the fn command line interface (CLI) utility
• Run fn start command which will download the Fn server docker image and start the Fn server

Before you Begin

Before we can install Fn you'll need:

1. A computer running Linux or MacOS. If you have a Windows machine the easiest thing to do is install VirtualBox and run a free Linux virtual machine.
2. Docker 17.05 (or higher) needs to be installed and running.

As you make your way through this tutorial, look out for this icon. Whenever you see it, it's time for you to perform an action.

Download and Install the fn CLI

From a terminal type the following:

curl -LSs https://raw.githubusercontent.com/fnproject/cli/master/install | sh

Once installed you'll see the fn CLI version printed out. You should see something similar to the following displayed (although likely with a later version number):

fn version 0.4.87

        ______
       / ____/___
      / /_  / __ \
     / __/ / / / /
    /_/   /_/ /_/`
    

Start the Fn Server

The final install step is to start the Fn server. Since Fn runs on Docker it'll need to be up and running too.

To start the Fn server you use the fn CLI. Run the fn start command. This will download the Fn server docker image and start the Fn Server on port 8080 by default. Note that this process runs in the foreground so that it's easy to stop with Ctrl-C:

fn start

If the Fn Server starts up successfully, you should see output similar to:

...
time="2018-05-10T11:32:49Z" level=info msg="available cpu" availCPU=2000 totalCPU=2000
time="2018-05-10T11:32:49Z" level=info msg="sync and async cpu reservations" cpuAsync=1600 cpuAsyncHWMark=1280 cpuSync=400

        ______
       / ____/___
      / /_  / __ \
     / __/ / / / /
    /_/   /_/ /_/
        v0.3.439

time="2018-05-10T11:32:49Z" level=info msg="Fn serving on `:8080`" type=full

Note: The Fn server creates a temporary data directory it uses to store metadata. If you want to retain this data after a restart, make sure you start Fn server in the same directory.

If you have some other process running on port 8080, fn start will fail with the following error:

docker: Error response from daemon: driver failed programming external connectivity on endpoint fnserver (d9478f85df4ef97d23d618c2318c243f1e8b65d69ca2547d889d80b148c5be09): Error starting userland proxy: Bind for 0.0.0.0:8080 failed: port is already allocated.
2018/05/10 16:49:25 error: processed finished with error exit status 125

In this case you can stop the other process and run fn start again. Alternatively, you can start Fn server on a different port.

Start the Fn Server on a Different Port

Fn Server starts on port 8080 by default. To use a different port use the --port or the -p option. For example

fn start -p 8081

When using a non-default port, you must point the fn CLI to the new port using the FN_API_URL environment variable:

export FN_API_URL=http://127.0.0.1:8081

Alternatively, you can also set the api_url using Fn contexts.

Test the Install

Let's verify everthing is up and running correctly.

Open a new terminal and run the following:

fn version

You should see the version of the fn CLI (client) and server displayed (your version will likely differ):

Client version:  0.4.87
Server version:  0.3.439

Note: If the server version is "?" then the fn CLI cannot reach the Fn server.
If this happens it's likely you have something else running on port 8080 or you started the server on a different port but forgot to set the FN_API_URL.

Learn More

Congratulations! You've installed Fn and started up an Fn server. Now you are ready to create your first function for one of the supported languages. You can start with:

• Go
• Java
• Node.js
• Ruby

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