Flipt OpenFeature Provider (Go)

Moved ⚠️

We have moved the Flipt OpenFeature Provider (Go) to the official OpenFeature Go Contrib repository. You can find the latest version of the Flipt OpenFeature Provider (Go) at: https://github.com/open-feature/go-sdk-contrib/tree/main/providers/flipt.

We will continue to maintain the Flipt OpenFeature Provider (Go) in the OpenFeature Go Contrib repository. Please open any issues or pull requests there.

In the future, we will be archiving this repository and eventually removing it.

Overview

This repository and package provides a Flipt OpenFeature Provider for interacting with the Flipt service backend using the OpenFeature Go SDK.

From the OpenFeature Specification:

Providers are the "translator" between the flag evaluation calls made in application code, and the flag management system that stores flags and in some cases evaluates flags.

Requirements

• Go 1.20+
• A running instance of Flipt

Breaking Changes

v0.2.0

Version v0.2.0 of this client correlates Boolean flag evaluations to Boolean flag types on the Flipt server. Upgrading to this version will require you to convert your flags that were using Boolean evaluation to the Boolean flag type on the Flipt server.

⚠️ Boolean flag evaluations were introduced in Flipt server (>= v.1.24.0).

v0.1.5

Version v0.1.5 of this client introduced a change to use a newer version of the Flipt API which requires use of the namespace parameter. This is to support the new namespace functionality added to Flipt v1.20.0.

This client uses the default namespace by default. If you are using a different namespace, you will need to set the namespace parameter when creating the provider:

provider := flipt.NewProvider(flipt.ForNamespace("my-namespace"))

⚠️ If you are running an older version of Flipt server (< v1.20.0), you should use a pre 0.1.5 version of this client.

Usage

Installation

go get go.flipt.io/flipt-openfeature-provider

Example

package main

import (
    "context"

    "go.flipt.io/flipt-openfeature-provider/pkg/provider/flipt"
    "github.com/open-feature/go-sdk/pkg/openfeature"
)


func main() {
    // http://localhost:8080 is the default Flipt address
    openfeature.SetProvider(flipt.NewProvider())

    client := openfeature.NewClient("my-app")
    value, err := client.BooleanValue(context.Background(), "v2_enabled", false, openfeature.EvaluationContext{
        TargetingKey: "[email protected]",
        Attributes: map[string]interface{}{
            "favorite_color": "blue",
        },
    })

    if err != nil {
        panic(err)
    }

    if value {
        // do something
    } else {
        // do something else
    }
}

Configuration

The Flipt provider allows you to communicate with Flipt over either HTTP(S) or GRPC, depending on the address provided.

HTTP(S)

provider := flipt.NewProvider(flipt.WithAddress("https://localhost:443"))

Unix Socket

provider := flipt.NewProvider(flipt.WithAddress("unix:///path/to/socket"))

GRPC

HTTP/2

type Token string

func (t Token) ClientToken() (string, error) {
    return t, nil
}

provider := flipt.NewProvider(
    flipt.WithAddress("grpc://localhost:9000"),
    flipt.WithCertificatePath("/path/to/cert.pem"), // optional
    flipt.WithClientProvider(Token("a-client-token")), // optional
)

Unix Socket

provider := flipt.NewProvider(
    flipt.WithAddress("unix:///path/to/socket"),
)