• Stars
    star
    646
  • Rank 69,672 (Top 2 %)
  • Language
    Go
  • License
    Apache License 2.0
  • Created over 6 years ago
  • Updated 3 months ago

Reviews

There are no reviews yet. Be the first to send feedback to the community and the maintainers!

Repository Details

Skycfg is an extension library for the Starlark language that adds support for constructing Protocol Buffer messages.

Skycfg

Skycfg is an extension library for the Starlark language that adds support for constructing Protocol Buffer messages. It was developed by Stripe to simplify configuration of Kubernetes services, Envoy routes, Terraform resources, and other complex configuration data.

At present, only the Go implementation of Starlark is supported.

API Documentation Test Status Test Coverage

Getting Started

The entry point to Skycfg is the skycfg.Load() function, which reads a configuration file from local disk. As the implementation stabilizes we expect to expand the public API surface so that Skycfg can be combined with other Starlark extensions.

Lets start with a simple main function that prints out every Protobuf message created by the config file hello.sky:

package main

import (
    "context"
    "fmt"
    "github.com/stripe/skycfg"
    _ "github.com/golang/protobuf/ptypes/wrappers"
)

func main() {
    ctx := context.Background()
    config, err := skycfg.Load(ctx, "hello.sky")
    if err != nil { panic(err) }
    messages, err := config.Main(ctx)
    if err != nil { panic(err) }
    for _, msg := range messages {
        fmt.Printf("%s\n", msg.String())
    }
}
# hello.sky
pb = proto.package("google.protobuf")

def main(ctx):
  return [pb.StringValue(value = "Hello, world!")]

Now we can build a small test driver and see what values are returned:

$ go get github.com/stripe/skycfg
$ go build -o test-skycfg
$ ./test-skycfg
value:"Hello, world!"
$

Success!

For more in-depth examples covering specific topics, see the _examples/ directory:

Why use Skycfg?

Compared to bare YAML or TOML, the Python-like syntax of Skycfg might not seem like a win. Why would we want configuration files with all those quotes and colons and braces?

There are four important benefits to using Skycfg over YAML:

Type Safety

Protobuf has a statically-typed data model, which means the type of every field is known to Skycfg when it's building your configuration. There is no risk of accidentally assigning a string to a number, a struct to a different struct, or forgetting to quote a YAML value.

pb = proto.package("google.protobuf")

def main(ctx):
  return [pb.StringValue(value = 123)]
$ ./test-skycfg
panic: TypeError: value 123 (type `int') can't be assigned to type `string'.

Functions

As in standard Python, you can define helper functions to reduce duplicated typing and share logic.

pb = proto.package("google.protobuf")

def greet(lang):
  greeting = {
    "en": "Hello, world!",
    "fr": "Bonjour, monde!",
  }[lang]
  return pb.StringValue(value = greeting)

def main(ctx):
  return [greet("en"), greet("fr")]
$ ./test-skycfg
value:"Hello world!"
value:"Bonjour, monde!"

Modules

Starlark supports importing modules from other files, which you can use to share common code between configurations. By default the paths to load are resolved on the local filesystem, but you can also override the load() handler to support syntaxes such as Bazel-style target labels.

Modules can protect service owners from complex Kubernetes logic:

load("//config/common/kubernetes.sky", "kubernetes")

def my_service(ctx):
  return kubernetes.pod(
      name = "my-namespace/my-service",
      containers = [
          kubernetes.container(name = "main", image = "index.docker.io/hello-world"),
      ]
  )

When combined with VCS hooks like GitHub CODEOWNERS, you can use modules to provide an API surface for third-party tools deployed in your infrastructure:

load("//config/common/constants.sky",  "CLUSTERS")
load("//config/production/k8s_dashboard/v1.10.0/main.sky",
     "kubernetes_dashboard")

def main(ctx):
  return [
    kubernetes_dashboard(ctx, cluster = CLUSTERS['ord1']),
    kubernetes_dashboard(ctx, cluster = CLUSTERS['ord1-canary']),
  ]

Context Variables

Skycfg supports limited dynamic behavior through the use of context variables, which let the Go caller pass arbitrary key:value pairs in the ctx parameter.

func main() {
    // ...
    messages, err := config.Main(ctx, skycfg.WithVars(starlark.StringDict{
      "revision": starlark.String("master/12345"),
    }))
pb = proto.package("google.protobuf")

def main(ctx):
  print("ctx.vars:", ctx.vars)
  return []
$ ./test-skycfg
[hello.sky:4] ctx.vars: {"revision": "master/12345"}

Contributing

We welcome contributions from the community. For small simple changes, go ahead and open a pull request. Larger changes should start out in the issue tracker, so we can make sure they fit into the roadmap. Changes to the Starlark language itself (such as new primitive types or syntax) should be applied to https://github.com/google/starlark-go.

Stability

Skycfg depends on internal details of the go-protobuf generated code, and as such may need to be updated to work with future versions of go-protobuf. We will release Skycfg v1.0 after all dependencies on go-protobuf implementation details have been fixed, which will be after the "api-v2" branch lands in a stable release of go-protobuf.

Our existing public APIs are expected to be stable even before the v1.0 release. Symbols that will change before v1.0 are hidden from the public docs and named Unstable*.

Known issues

gogo/protobuf support

Skycfg has dropped support for gogo/protobuf, an alternative protobuf go code generator, when upgrading to using the go-protobuf v2 api. For using gogo support, see [email protected] (Skycfg prior to switching to v2).

More Repositories

1

stripe-node

Node.js library for the Stripe API.
TypeScript
3,874
star
2

stripe-php

PHP library for the Stripe API.
PHP
3,736
star
3

stripe-go

Go library for the Stripe API.
Go
2,144
star
4

stripe-ios

Stripe iOS SDK
Swift
2,110
star
5

stripe-ruby

Ruby library for the Stripe API.
Ruby
1,952
star
6

react-stripe-js

React components for Stripe.js and Stripe Elements
TypeScript
1,757
star
7

veneur

A distributed, fault-tolerant pipeline for observability data
Go
1,734
star
8

stripe-python

Python library for the Stripe API.
Python
1,669
star
9

stripe-cli

A command-line tool for Stripe
Go
1,609
star
10

stripe-mock

stripe-mock is a mock HTTP server that responds like the real Stripe API. It can be used instead of Stripe's testmode to make test suites integrating with Stripe faster and less brittle.
Go
1,374
star
11

stripe-dotnet

Stripe.net is a sync/async .NET 4.6.1+ client, and a portable class library for stripe.com.
C#
1,362
star
12

stripe-android

Stripe Android SDK
Kotlin
1,277
star
13

stripe-react-native

React Native library for Stripe.
TypeScript
1,272
star
14

smokescreen

A simple HTTP proxy that fogs over naughty URLs
Go
1,081
star
15

elements-examples

Stripe Elements examples.
HTML
996
star
16

stripe-java

Java library for the Stripe API.
Java
818
star
17

stripe-connect-rocketrides

Sample on-demand platform built on Stripe: Connect onboarding for pilots, iOS app for passengers to request rides.
Swift
634
star
18

stripe-js

Loading wrapper for Stripe.js
TypeScript
625
star
19

poncho

Easily create REST APIs
Ruby
516
star
20

rainier

Bayesian inference in Scala.
Scala
433
star
21

openapi

An OpenAPI specification for the Stripe API.
391
star
22

pg-schema-diff

Go library for diffing Postgres schemas and generating SQL migrations
Go
364
star
23

stripe-billing-typographic

⚡️Typographic is a webfont service (and demo) built with Stripe Billing.
JavaScript
216
star
24

subprocess

A port of Python's subprocess module to Ruby
Ruby
208
star
25

carbon-removal-source-materials

Source materials supporting Stripe Climate carbon removal purchases (http://stripe.com/climate)
190
star
26

stripe-apps

Stripe Apps lets you embed custom user experiences directly in the Stripe Dashboard and orchestrate the Stripe API.
TypeScript
148
star
27

dagon

Tools for rewriting and optimizing DAGs (directed-acyclic graphs) in Scala
Scala
148
star
28

bonsai

Beautiful trees, without the landscaping.
Scala
141
star
29

ios-dashboard-ui

[DEPRECATED] UI components from the Stripe Dashboard iOS app
Swift
138
star
30

vscode-stripe

Stripe for Visual Studio Code
TypeScript
123
star
31

stripe.github.io

A landing page for Stripe's GitHub organization
HTML
117
star
32

stripe-terminal-react-native

React Native SDK for Stripe Terminal
TypeScript
108
star
33

example-mobile-backend

A simple, easy-to-deploy backend that you can use to demo our example mobile apps.
Ruby
106
star
34

stripe-terminal-ios

Stripe Terminal iOS SDK
Objective-C
102
star
35

stripe-demo-connect-roastery-saas-platform

Roastery demo SaaS platform using Stripe Connect
JavaScript
94
star
36

stripe-terminal-android

Stripe Terminal Android SDK
Java
93
star
37

example-terminal-backend

A simple, easy-to-deploy backend that you can use to run the Stripe Terminal example apps
Ruby
88
star
38

stripe-terminal-js-demo

Demo app for the Stripe Terminal JS SDK
JavaScript
82
star
39

stripe-postman

Postman collection for Stripe's API
77
star
40

unilog

A logger for use with daemontools.
Go
77
star
41

goforit

A feature flags client library for Go
Go
70
star
42

stripe-connect-custom-rocketdeliveries

Sample on-demand platform built on Stripe Connect: Custom Accounts and Connect Onboarding for deliveries. https://rocketdeliveries.io
JavaScript
69
star
43

tracer-objc

Generic record & playback framework for Objective-C
Objective-C
52
star
44

mobile-viewport-control

Dynamically control the mobile viewport
JavaScript
48
star
45

log4j-remediation-tools

Tools for remediating the recent log4j2 RCE vulnerability (CVE-2021-44228)
Go
41
star
46

terminal-js

Loading wrapper for the Terminal JS SDK
TypeScript
34
star
47

stripe-connect-furever-demo

Code sample demo built on Stripe Connect embedded components.
TypeScript
34
star
48

stripe-identity-react-native

React Native library for Stripe Identity
TypeScript
33
star
49

stripe-reachability

A bash script to test access to the Stripe API
Shell
32
star
50

krl

OpenSSH Key Revocation List support for Go
Go
30
star
51

stripe-magento2-releases

27
star
52

react-connect-js

React components for Connect.js and Connect embedded components
TypeScript
22
star
53

connect-js

Loading wrapper for Connect.js
TypeScript
21
star
54

stripe-mirakl-connector

Official Stripe Mirakl Connector
PHP
13
star
55

salesforce-connector-examples

Stripe Salesforce Connector examples
Apex
12
star
56

checkout-sales-demo

Sales demo of Stripe Checkout with different locales around the world.
HTML
12
star
57

stripe-ios-spm

Swift Package Manager mirror for the Stripe iOS SDK. See http://github.com/stripe/stripe-ios for details.
12
star
58

.github

Stripe uses the Contributor Covenant Code of Conduct for our open-source community.
8
star
59

homebrew-stripe-mock

Homebrew tap for stripestub
Ruby
7
star
60

scoop-stripe-cli

7
star
61

homebrew-stripe-cli

Ruby
7
star
62

stripe-sfcc-b2c-connector

JavaScript
7
star
63

stripe-commercetools-connect-app

TypeScript
5
star
64

ssf-ruby

A Ruby client for the Sensor Sensibility Format
Ruby
5
star
65

terminal-connector-releases

Release binaries for Stripe Terminal connectors
3
star
66

open-banking-v2-docs

Open banking docs for V2 APIs
CSS
2
star
67

vscode-endsmart

vscode extension to smartly add `end` keywords
TypeScript
1
star