Checkout.com Golang SDK

Getting started

Version 1.0.0 is here!

We improved the initialization of SDK making it easier to understand the available options.
Now NAS accounts are the default instance for the SDK and ABC structure was moved to a previous prefixes.

Module installer

Make sure your project is using Go Modules:

go get github.com/checkout/checkout-sdk-go@{version}

Then import the library into your code:

import "github.com/checkout/checkout-sdk-go"

🚀 Please check in GitHub releases for all the versions available.

📖 Checkout our official documentation.

• Official Docs (Default)
• Official Docs (Previous)

📚 Check out our official API documentation guide, where you can also find more usage examples.

• API Reference (Default)
• API Reference (Previous)

How to use the SDK

This SDK can be used with two different pair of API keys provided by Checkout. However, using different API keys imply using specific API features.
Please find in the table below the types of keys that can be used within this SDK.

Account System	Public Key (example)	Secret Key (example)
Default	pk_pkhpdtvabcf7hdgpwnbhw7r2uic	sk_m73dzypy7cf3gf5d2xr4k7sxo4e
Previous	pk_g650ff27-7c42-4ce1-ae90-5691a188ee7b	sk_gk3517a8-3z01-45fq-b4bd-4282384b0a64

Note: sandbox keys have a sbox_ or test_ identifier, for Default and Previous accounts respectively.

If you don't have your own API keys, you can sign up for a test account here.

PLEASE NEVER SHARE OR PUBLISH YOUR CHECKOUT CREDENTIALS.

Default

Default keys client instantiation can be done as follows:

import (
    "github.com/checkout/checkout-sdk-go"
    "github.com/checkout/checkout-sdk-go/configuration"
)

api, err := checkout.Builder().
                     StaticKeys().
                     WithEnvironment(configuration.Sandbox()).
                     WithSecretKey("secret_key").
                     WithPublicKey("public_key"). // optional, only required for operations related with tokens
                     Build()

Default OAuth

The SDK supports client credentials OAuth, when initialized as follows:

import (
    "github.com/checkout/checkout-sdk-go"
    "github.com/checkout/checkout-sdk-go/configuration"
)

api, err := checkout.Builder().
                     OAuth().
                     WithAuthorizationUri("https://access.sandbox.checkout.com/connect/token"). // optional, custom authorization URI
                     WithClientCredentials("client_id", "client_secret").
                     WithEnvironment(configuration.Sandbox()).
                     WithScopes(getOAuthScopes()).
                     Build()

Previous

If your pair of keys matches the previous system type, this is how the SDK should be used:

import (
    "github.com/checkout/checkout-sdk-go"
    "github.com/checkout/checkout-sdk-go/configuration"
)

api, err := checkout.Builder().
                     Previous().
                     WithEnvironment(configuration.Sandbox()).
                     WithSecretKey("secret_key").
                     WithPublicKey("public_key"). // optional, only required for operations related with tokens
                     Build()

Then just get any client, and start making requests:

import (
    "github.com/checkout/checkout-sdk-go/payments"
    "github.com/checkout/checkout-sdk-go/payments/nas"
)

request := nas.PaymentRequest{}
response, err := api.Payments.RequestPayment(request)

Error Handling

All the API responses that do not fall in the 2** status codes will return a errors.CheckoutApiError. The error encapsulates the StatusCode, Status and a the ErrorDetails, if available.

Custom Http Client

Go SDK supports your own configuration for http client using http.Client from the standard library. You can pass it through when instantiating the SDK as follows:

import (
    "net/http"
    
    "github.com/checkout/checkout-sdk-go"
    "github.com/checkout/checkout-sdk-go/configuration"
)

httpClient := http.Client{
    Timeout: time.Duration(20) * time.Millisecond,
}

api, err := checkout.Builder().
                     StaticKeys().
                     WithEnvironment(configuration.Sandbox()).
                     WithHttpClient(&httpClient).
                     WithSecretKey("secret_key")).
                     WithPublicKey("public_key")). // optional, only required for operations related with tokens
                     Build()

Logging

The SDK supports custom Log provider. You can provide your log configuration via SDK initialization. By default, the SDK uses the log package from the standard library.

import (
    "log"	
	
    "github.com/checkout/checkout-sdk-go"
    "github.com/checkout/checkout-sdk-go/configuration"
)

logger := log.New(os.Stderr, "checkout-sdk-go - ", log.LstdFlags)

api, err := checkout.Builder().
                     StaticKeys().
                     WithEnvironment(configuration.Sandbox()).
                     WithSecretKey("secret_key")).
                     WithPublicKey("public_key")). // optional, only required for operations related with tokens
                     WithLogger(logger) // your own custom configuration
                     Build()

Custom Environment

In case that you want to use an integrator or mock server, you can specify your own URI configuration as follows:

import (
    "github.com/checkout/checkout-sdk-go"
    "github.com/checkout/checkout-sdk-go/configuration"
)

environment := configuration.NewEnvironment(
	"https://the.base.uri/", // the uri for all CKO operations 
	"https://the.oauth.uri/connect/token", // the uri used for OAUTH authorization, only required for OAuth operations 
	"https://the.files.uri/", // the uri used for Files operations, only required for Accounts module 
	"https://the.transfers.uri/", // the uri used for Transfer operations, only required for Transfers module 
	"https://the.balances.uri/", // the uri used for Balances operations, only required for Balances module false 
)

api, err := checkout.Builder().
                     StaticKeys().
                     WithEnvironment(environment).
                     WithSecretKey("secret_key")).
                     WithPublicKey("public_key")). // optional, only required for operations related with tokens
                     Build()

Building from source

Once you check out the code from GitHub, the project can be built using:

go mod tidy

go build

The execution of integration tests require the following environment variables set in your system:

• For default account systems (NAS): CHECKOUT_DEFAULT_PUBLIC_KEY & CHECKOUT_DEFAULT_SECRET_KEY
• For default account systems (OAuth): CHECKOUT_DEFAULT_OAUTH_CLIENT_ID & CHECKOUT_DEFAULT_OAUTH_CLIENT_SECRET
• For Previous account systems (ABC): CHECKOUT_PREVIOUS_PUBLIC_KEY & CHECKOUT_PREVIOUS_SECRET_KEY

Telemetry

Request telementry is enabled by default in the Go SDK. Request latency is included in the telemetry data. Recording the request latency allows Checkout.com to continuously monitor and imporove the merchant experience.

Request telemetry can be disabled by opting out during checkout_sdk_builder builder step:

api := checkout.Builder().
    Previous().
    WithSecretKey("CHECKOUT_PREVIOUS_SECRET_KEY").
    WithEnvironment(configuration.Sandbox()).
    WithEnableTelemetry(false).
    Build()

Code of Conduct

Please refer to Code of Conduct

Licensing

MIT