A Standard Library for Microservices

stdlib is a Standard Library for Microservices

We just launched our Developer Preview!

Use stdlib to build production-ready, auto-scaled, "server-less" microservices in minutes.

stdlib has three components:

1. A central registry for microservices
2. A distribution platform for hosting at scale
3. A development framework for package management and service creation

It is the fastest, easiest way to begin building microservices on your own or with a team, and currently supports Node.js 6.5.0. The distribution and hosting platform for execution of your services is built atop AWS Lambda ensuring both the scale and reliability you would expect for production-ready services.

Table of Contents

1. Getting Started
2. Creating Your First Service
3. Connecting Service Endpoints
4. Accessing Your Microservices From Other Applications
5. Accessing Your Microservices Over HTTP
6. Version Control and Package Management
7. Additional Functionality
8. Acknowledgements
9. Contact

Getting Started

To get started with stdlib, first make sure you have Node 6.x installed, available from the official Node.js website. Next install the stdlib CLI tools with:

$ npm install [email protected] -g

And you're now ready to start building!

Creating Your First Service

The first thing you'll want to do is create a workspace. Create a new directory you intend to build your services in and initialize the workspace.

$ mkdir stdlib-workspace
$ cd stdlib-workspace
$ stdlib init

You'll be asked for an e-mail address to log in to the stdlib registry, via the Polybit API server. If you don't yet have an account, you can create one from the command line. Note that you can skip account creation with stdlib init --no-login. You'll be unable to use the registry, but it's useful for creating workspaces when you don't have internet access.

Next, create your service:

$ stdlib create <service>

You'll be asked for a default function name, which is the entry point into your service (useful if you only want a single entry point). This will automatically generate a service project scaffold in stdlib-workspace/<username>/<service>.

Once created, enter the service directory:

$ cd your-username/your-service

In this directory, you'll see something like:

- f/
  - defaultFunction/
	  - function.json
		- index.js
- package.json
- env.json
- README.md

At this point, there's a "hello world" function that's been automatically created. stdlib comes paired with a simple f command for testing your functions locally and running them in the cloud. To test your function:

$ f .
> "hello world"

If we examine the f/defaultFunction/index.js file, we see the following:

module.exports = (params, callback) => {

  callback(null, 'hello world');

};

If necessary, we can pass some of these parameters to it (params.args and params.kwargs) using:

f . arg0 arg1 --kwarg0 "Hello World" --kwarg1 Goodbye

Though it won't change the function output as-is. params.args would be equal to ["arg0", "arg1"] and params.kwargs would be {"kwarg0":"Hello World","kwarg1":"Goodbye"}.

Pushing to the Cloud

To push your function to a development environment in the cloud...

$ stdlib up dev
$ f your-username/your-service@dev
> "hello world"

And to release it (when you're ready!)

$ stdlib release
$ f your-username/your-service
> "hello world"

You can check out your service on the web, and use it in applications at:

https://f.stdlib.com/your-username/your-service

That's it! You haven't written a line of code yet, and you have mastery over building a service, testing it in a development (staging) environment online, and releasing it for private (or public) consumption.

Note: You'll need to set "publish": true in the stdlib key of your package.json file to see your service appear in the public registry. It's set to false by default.

Another Note: Staging environments (like the one created with stdlib up dev) are mutable and can be replaced indefinitely. Releases (stdlib release) are immutable and can never be overwritten. However, any service can be torn down with stdlib down <environment> or stdlib down -r <version> (but releases can't be replaced once removed, to prevent mistakes and / or bad actors).

Connecting Service Endpoints

You'll notice that you can create more than one function per service. While you can structure your project however you'd like internally, it should also be noted that these functions have zero-latency access to each other. You can access them internally with the f package on NPM, which behaves similarly to the f command for testing. Use:

$ npm install f --save

In your main service directory to add it, and use it like so:

f/add/index.js

module.exports = (params, callback) => {

	return callback(null, params.args[1] + params.args[2]);

};

f/add-double/index.js

const f = require('f');

module.exports = (params, callback) => {

	return f('./add')(params.args[0], params.args[1], (err, result) => {

		callback(err, result * 2);

	});

};

In this case, calling f ./add 1 2 will return 3 and f ./add-double 1 2 will return 6. These map directly to individual service endpoints. Note that when chaining like this, a single service execution instance is being used so be careful about setting service timeouts appropriately.

Accessing Your Microservices From Other Applications

As mentioned in the previous section, you can use the f library that's available on GitHub and NPM to access your microservices from legacy Node.js applications and even the web browser. We'll have more SDKs coming out in the following months.

A legacy app would call a function with...

// Legacy code
var f = require('f');

f('username/[email protected]')('hello', 'world', {keyword: 'argument'}, function (err, result) {

	if (err) {
		// handle it
	}

	// do something with result

});

Which would speak to your microservice...

module.exports = (params, callback) => {

	params.args[0] === 'hello'; // true
	params.args[1] === 'world'; // true
	params.kwargs.keyword === 'argument'; // true

	callback(null, 'Done!');

};

Accessing Your Microservices Over HTTP

We definitely recommend using the browser-based version of f to make microservice calls as specified above, but you can also make HTTPS requests directly to the stdlib gateway. HTTP query parameters are mapped automatically to keyword arguments:

https://f.stdlib.com/username/[email protected]?name=Keith

Maps directly to:

module.exports = (params, callback) => {

	params.kwargs.name === 'Keith'; // true

	callback(null, 'Done!');

};

Note that you will not be able to pass in anything to the params.args parameter.

Version Control and Package Management

A quick note on version control - stdlib is not a replacement for normal git-based workflows, it is a supplement focused around service creation and execution.

You have unlimited access to any release (that hasn't been torn down) with stdlib pkg <serviceIdentifier> to download the tarball (.tgz) and stdlib get <serviceIdentifier> to automatically download and unpack the tarball to a working directory.

Tarballs (and package contents) are closed-source. Nobody but you (and potentially your teammates) has access to these. It's up to you whether or not you share the guts of your service with others on GitHub or NPM.

As mentioned above: releases are immutable and can not be overwritten (but can be removed, just not replaced afterwards) and development / staging environments are mutable, you can overwrite them as much as you'd like.

Additional Functionality

stdlib comes packed with a bunch of other goodies - if your service goes down for any reason (the service platform is acting up), use stdlib restart. Similarly, as we roll out updates to the platform the builds we're using on AWS Lambda may change. You can update your service to our latest build using stdlib rebuild. We may recommend this from time-to-time, so pay attention to e-mails and the community.

To see a full list of commands available for the CLI tools, type:

$ stdlib help

We've conveniently copy-and-pasted the output here for you to peruse;

create [service]
	-n                   No login - don't require an internet connection
	-w                   Write over - overwrite the current directory contents
	-x                   The default function name
	--function           The default function name
	--no-login           No login - don't require an internet connection
	--write-over         Write over - overwrite the current directory contents

	Creates a new (local) service

down [environment]
	-r                   Remove a release version (provide number)
	--release            Remove a release version (provide number)

	Removes stdlib package from registry and cloud environment

f:create [function name]
	-w                   Overwrite existing function
	--write-over         Overwrite existing function

	Creates a new function for a (local) service

get [environment]
	-f                   Force command if not in root directory
	-r                   Specify a release package
	-w                   Write over - overwrite the target directory contents
	--force              Force command if not in root directory
	--release            Specify a release package
	--write-over         Write over - overwrite the target directory contents

	Retrieves and extracts stdlib package

info [username | full service name]
	Retrieves information about a user or package

init [environment]
	-f                   Force command to overwrite existing workspace
	-n                   No login - don't require an internet connection
	--force              Force command to overwrite existing workspace
	--no-login           No login - don't require an internet connection

	Initializes stdlib workspace

login
	Logs in to stdlib in this directory

logout
	Logs out of stdlib in this workspace

pkg [full service name]
	-f                   Force command if not in root directory
	-o                   Output path for the .tgz package
	--force              Force command if not in root directory
	--output             Output path for the .tgz package

	Downloads stdlib tarball (.tgz)

rebuild [environment]
	-r                   Rebuild a release package
	--release            Rebuild a release package

	Rebuilds a service (useful for registry performance updates), alias of stdlib restart -b

register
	Registers a new stdlib user account

release
	Pushes release of stdlib package to registry and cloud (Alias of stdlib up -r)

restart [environment]
	-b                   Rebuild service fully
	-r                   Restart a release package
	--build              Rebuild service fully
	--release            Restart a release package

	Restarts a service (if necessary)

rollback
	Rolls back (removes) release of stdlib package

up [environment]
	-r                   Upload a release package
	--release            Upload a release package

	Pushes stdlib package to registry and cloud environment

That's it!

Yep, it's really that easy. To keep up-to-date on developments, please star us here on GitHub, and sign up a user account for the registry. You can read more about service hosting and keep track of official updates on the official stdlib website, stdlib.com.

Acknowledgements

stdlib is a product of and © 2016 Polybit Inc.

It wouldn't have been possible without a bunch of amazing people.

• Brian LeRoux gave us our first push and kickstarted us in this direction.

• Boris Mann threw his support in from day one when we first launched Nodal.

• TJ Holowaychuk has been consistently sharing great ideas about the server-less movement and his Apex Framework has certainly been an inspiration.

• The amazingly talented people and friends of AngelPad always pick us up when we're low and put us in our place when we need to get work done.

Contact

We'd love for you to pay attention to @Polybit and what we're building next! If you'd consider joining the team, shoot us an e-mail.

You can also follow me, the original author, on Twitter: @keithwhor.

Issues encouraged, PRs welcome, and we're happy to have you on board! Enjoy and happy building :)