Longbridge OpenAPI SDK for Go

Longbridge provides an easy-to-use interface for invoking Longbridge OpenAPI.

Quickstart

With Go module support , simply add the following import

import "github.com/longbridge/openapi-go"

Authentication

Longbridge OpenAPI supports two authentication methods:

1. OAuth 2.0 (Recommended) — Bearer tokens, no HMAC; token is stored and refreshed automatically. See Config: Using OAuth 2.0.
2. Legacy API Key — App key, secret, and access token via environment variables. See Config: Using Legacy API Key.

If you use OAuth, register an OAuth client first to get your client_id:

curl -X POST https://openapi.longbridge.com/v1/oauth2/client/register \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My Application",
    "redirect_uris": ["http://localhost:60355/callback"],
    "grant_types": ["authorization_code", "refresh_token"]
  }'

Response:

{
  "client_id": "your-client-id-here",
  "name": "My Application",
  "redirect_uris": ["http://localhost:60355/callback"]
}

Save the client_id for use when building config (see Config section below).

Config

You can create a Config in two ways: with OAuth (recommended) or with legacy API key (environment variables). The examples in this README use OAuth.

Using OAuth 2.0 (Recommended)

Token storage: After the authorization flow, the SDK stores the access and refresh tokens under ~/.longbridge/openapi/tokens/<client_id> (or %USERPROFILE%\.longbridge\openapi\tokens\<client_id> on Windows). It loads and refreshes them automatically on later runs, so you typically authorize once per machine.

import (
    "context"
    "fmt"
    "log"

    "github.com/longbridge/openapi-go/config"
    "github.com/longbridge/openapi-go/oauth"
)

func main() {
    o := oauth.New("your-client-id").
        OnOpenURL(func(url string) {
            fmt.Println("Please visit:", url)
        })
    if err := o.Build(context.Background()); err != nil {
        log.Fatal(err)
    }

    cfg, err := config.New(config.WithOAuthClient(o))
    if err != nil {
        log.Fatal(err)
    }
    // Use cfg with quote.NewFromCfg(cfg), trade.NewFromCfg(cfg), http.NewFromCfg(cfg), etc.
}

Benefits: No shared secret; no per-request HMAC; token load/refresh/persist is automatic.

Using Legacy API Key (Environment Variables)

For backward compatibility you can use the traditional three keys. Load from env and Load from file (see below) only support Legacy API Key (app key, secret, access token); they do not support OAuth. Set env vars (or a .env file), then call config.New().

macOS / Linux

export LONGBRIDGE_APP_KEY="App Key get from user center"
export LONGBRIDGE_APP_SECRET="App Secret get from user center"
export LONGBRIDGE_ACCESS_TOKEN="Access Token get from user center"

Windows

setx LONGBRIDGE_APP_KEY "App Key get from user center"
setx LONGBRIDGE_APP_SECRET "App Secret get from user center"
setx LONGBRIDGE_ACCESS_TOKEN "Access Token get from user center"

c, err := config.New()
if err != nil {
    log.Fatal(err)
}
// Use c with NewFromCfg(c) for quote, trade, http.

All supported env vars are listed in Environment Variables.

Load From File (YAML, TOML)

Load from file (and load from env above) only supports Legacy API Key. For OAuth, use Using OAuth 2.0 (Recommended).

YAML Example

To load configuration from a YAML file, use the following code snippet:

conf, err := config.New(config.WithFilePath("./test.yaml"))

Here is an example of what the test.yaml file might look like:

longbridge:
  app_key: xxxxx
  app_secret: xxxxx 
  access_token: xxxxx 

TOML Example

Similarly, to load configuration from a TOML file, use this code snippet:

conf, err := config.New(config.WithFilePath("./test.toml"))

And here is an example of a test.toml file:

[longbridge]
app_key = "xxxxx"
app_secret = "xxxxx"
access_token = "xxxxx"

Init Config Manually

Config structure as follow:

type Config struct {
    HttpURL     string        `env:"LONGBRIDGE_HTTP_URL" yaml:"http_url" toml:"http_url"`
    HTTPTimeout time.Duration `env:"LONGBRIDGE_HTTP_TIMEOUT" yaml:"http_timeout" toml:"http_timeout"`
    AppKey      string        `env:"LONGBRIDGE_APP_KEY" yaml:"app_key" toml:"app_key"`
    AppSecret   string        `env:"LONGBRIDGE_APP_SECRET" yaml:"app_secret" toml:"app_secret"`
    AccessToken string        `env:"LONGBRIDGE_ACCESS_TOKEN" yaml:"access_token" toml:"access_token"`
    TradeUrl    string        `env:"LONGBRIDGE_TRADE_URL" yaml:"trade_url" toml:"trade_url"`
    QuoteUrl    string        `env:"LONGBRIDGE_QUOTE_URL" yaml:"quote_url" toml:"quote_url"`
    EnableOvernight bool          `env:"LONGBRIDGE_ENABLE_OVERNIGHT" yaml:"enable_overnight" toml:"enable_overnight"`
    Language    openapi.Language `env:"LONGBRIDGE_LANGUAGE" yaml:"language" toml:"language"`

    LogLevel string `env:"LONGBRIDGE_LOG_LEVEL" yaml:"log_level" toml:"log_level"`
    // Longbridge protocol config
    AuthTimeout    time.Duration `env:"LONGBRIDGE_AUTH_TIMEOUT" yaml:"auth_timeout" toml:"timeout"`
    Timeout        time.Duration `env:"LONGBRIDGE_TIMEOUT" yaml:"timeout" toml:"timeout"`
    WriteQueueSize int           `env:"LONGBRIDGE_WRITE_QUEUE_SIZE" yaml:"write_queue_size" toml:"write_queue_size"`
    ReadQueueSize  int           `env:"LONGBRIDGE_READ_QUEUE_SIZE" yaml:"read_queue_size" toml:"read_queue_size"`
    ReadBufferSize int           `env:"LONGBRIDGE_READ_BUFFER_SIZE" yaml:"read_buffer_size" toml:"read_buffer_size"`
    MinGzipSize    int           `env:"LONGBRIDGE_MIN_GZIP_SIZE" yaml:"min_gzip_size" toml:"min_gzip_size"`
    Region Region `env:"LONGBRIDGE_REGION" yaml:"region" toml:"region"`
}

set config field manually

c, err := config.New()
c.AppKey = "xxx"
c.AppSecret = "xxx"
c.AccessToken = "xxx"

Set Custom Logger

Our logger interface as follow:

type Logger interface {
    SetLevel(string)
    Info(msg string)
    Error(msg string)
    Warn(msg string)
    Debug(msg string)
    Infof(msg string, args ...interface{})
    Errorf(msg string, args ...interface{})
    Warnf(msg string, args ...interface{})
    Debugf(msg string, args ...interface{})
}

Your can use you own logger by imply the interface

c, err := config.New()

l := newOwnLogger()

c.SetLogger(l)

Use Custom *(net/http).Client

the default http client is initialized simply as follow:

cli := &http.Client{Timeout: opts.Timeout}

we only set timeout here, you can use you own *(net/http).Client.

c, err := config.New()

c.Client = &http.Client{
    Transport: ...
}

Quote API (Get Basic Information of Securities)

package main

import (
    "context"
    "fmt"
    "log"

    "github.com/longbridge/openapi-go/config"
    "github.com/longbridge/openapi-go/oauth"
    "github.com/longbridge/openapi-go/quote"
)

func main() {
    o := oauth.New("your-client-id").
        OnOpenURL(func(url string) {
            fmt.Println("Please visit:", url)
        })
    if err := o.Build(context.Background()); err != nil {
        log.Fatal(err)
    }
    cfg, err := config.New(config.WithOAuthClient(o))
    if err != nil {
        log.Fatal(err)
    }
    quoteContext, err := quote.NewFromCfg(cfg)
    if err != nil {
        log.Fatal(err)
    }
    defer quoteContext.Close()
    quotes, err := quoteContext.Quote(context.Background(), []string{"700.HK", "AAPL.US", "TSLA.US", "NFLX.US"})
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("quotes: %v", quotes)
}

Trade API (Submit Order)

package main

import (
    "context"
    "fmt"
    "log"

    "github.com/longbridge/openapi-go/config"
    "github.com/longbridge/openapi-go/oauth"
    "github.com/longbridge/openapi-go/trade"
    "github.com/shopspring/decimal"
)

func main() {
    o := oauth.New("your-client-id").
        OnOpenURL(func(url string) {
            fmt.Println("Please visit:", url)
        })
    if err := o.Build(context.Background()); err != nil {
        log.Fatal(err)
    }
    cfg, err := config.New(config.WithOAuthClient(o))
    if err != nil {
        log.Fatal(err)
    }
    tradeContext, err := trade.NewFromCfg(cfg)
    if err != nil {
        log.Fatal(err)
    }
    defer tradeContext.Close()
    order := &trade.SubmitOrder{
        Symbol:            "700.HK",
        OrderType:         trade.OrderTypeLO,
        Side:              trade.OrderSideBuy,
        SubmittedQuantity: 200,
        TimeInForce:       trade.TimeTypeDay,
        SubmittedPrice:    decimal.NewFromFloat(12),
    }
    orderId, err := tradeContext.SubmitOrder(context.Background(), order)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("orderId: %v\n", orderId)
}

Environment Variables

Support load env from .env file.

name	description	default value	example	optional
LONGBRIDGE_REGION	Set access region, if region equals cn, SDK will set httpUrl, quoteUrl, tradeUrl to China endpoints	-	cn	cn
LONGBRIDGE_HTTP_URL	Longbridge REST API URL	https://openapi.longbridge.com
LONGBRIDGE_APP_KEY	app key
LONGBRIDGE_APP_SECRET	app secret
LONGBRIDGE_ACCESS_TOKEN	access token
LONGBRIDGE_TRADE_URL	Longbridge protocol URL for trade context	wss://openapi-trade.longbridge.com
LONGBRIDGE_QUOTE_URL	Longbridge protocol URL for quote context	wss://openapi-quote.longbridge.com
LONGBRIDGE_LOG_LEVEL	log level	info
LONGBRIDGE_AUTH_TIMEOUT	Longbridge protocol authorize request timeout	10 second	10s
LONGBRIDGE_TIMEOUT	Longbridge protocol dial timeout	5 second	6s
LONGBRIDGE_WRITE_QUEUE_SIZE	Longbridge protocol write queue size	16
LONGBRIDGE_READ_QUEUE_SIZE	Longbridge protocol read queue size	16
LONGBRIDGE_READ_BUFFER_SIZE	Longbridge protocol read buffer size	4096
LONGBRIDGE_MIN_GZIP_SIZE	Longbridge protocol minimal gzip size	1024
LONGBRIDGE_ENABLE_OVERNIGHT	enable overnight quote subscription feature	false
LONGBRIDGE_LANGUAGE	set user language for some information.	-	en	en,zh-CN,zh-HK

License

Licensed under either of

• Apache License, Version 2.0,(LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT) at your option.