brokeyourbike/clearbank-api-client-go

package clearbank

import (
    "context"
    "fmt"
    "net/http"
    "strings"

    "github.com/google/uuid"
)

type FxClient interface {
    InitiateFxOrder(context.Context, FXPayload) error
    RequestFxQuote(ctx context.Context, payload FXQuotePayload) (data FXQuoteResponse, err error)
    ExecuteFxQuote(ctx context.Context, payload FXPayload) error
}

type FXAttestation string

const (
    FXAttestationSameOwner      FXAttestation = "Y"
    FXAttestationDifferentOwner FXAttestation = "N"
)

type FXAccount struct {
    Owner string `json:"owner"`
    IBAN  string `json:"iban"`
}

type FXTradeInformationMargin struct {
    Amount  float64   `json:"amount"`
    Account FXAccount `json:"account"`
}

type FXTradeInformation struct {
    ValueDate string `json:"valueDate,omitempty"`
    Details   struct {
        InstructedAmount float64   `json:"instructedAmount"`
        FixedSide        FixedSide `json:"fixedSide"`
        SellCurrency     string    `json:"sellCurrency"`
        BuyCurrency      string    `json:"buyCurrency"`
    } `json:"details"`
    Margin                  *FXTradeInformationMargin `json:"margin,omitempty"`
    EndToEndID              string                    `json:"endToEndId"`
    UnstructuredInformation string                    `json:"unstructuredInformation,omitempty"`
}

type FXPayload struct {
    QuoteID             *uuid.UUID `json:"quoteId,omitempty"`
    CustomerInformation struct {
        SellAccount FXAccount     `json:"sellAccount"`
        BuyAccount  FXAccount     `json:"buyAccount"`
        Attestation FXAttestation `json:"attestation"`
    } `json:"customerInformation"`
    MarginAccount    *FXAccount          `json:"marginAccount,omitempty"`
    TradeInformation *FXTradeInformation `json:"tradeInformation,omitempty"`
}

func (c *client) InitiateFxOrder(ctx context.Context, payload FXPayload) error {
    req, err := c.newRequest(ctx, http.MethodPost, "/fx/v1/order", payload)
    if err != nil {
        return fmt.Errorf("failed to create request: %w", err)
    }

    req.ExpectStatus(http.StatusAccepted)
    return c.do(ctx, req)
}

type QuoteFixedSide string

const (
    QuoteFixedSideBuy  QuoteFixedSide = "Buy"
    QuoteFixedSideSell QuoteFixedSide = "Sell"
)

type FXQuotePayload struct {
    SellCurrency     string         `json:"SellCurrency"`
    BuyCurrency      string         `json:"BuyCurrency"`
    InstructedAmount float64        `json:"InstructedAmount"`
    FixedSide        QuoteFixedSide `json:"FixedSide"`
    ValueDate        string         `json:"ValueDate"`
    Margin           *float64       `json:"Margin,omitempty"`
}

type FXQuoteResponse struct {
    QuoteID      uuid.UUID `json:"QuoteId"`
    ValueDate    string    `json:"ValueDate"`
    CurrencyPair string    `json:"CurrencyPair"`
    ExchangeRate float64   `json:"ExchangeRate"`
    SellCurrency string    `json:"SellCurrency"`
    SellAmount   float64   `json:"SellAmount"`
    BuyCurrency  string    `json:"BuyCurrency"`
    BuyAmount    float64   `json:"BuyAmount"`
    CreatedAt    Time      `json:"CreatedAt"`
    ExpiresAt    Time      `json:"ExpiresAt"`
    QuoteRequest struct {
        ValueDate        string  `json:"ValueDate"`
        InstructedAmount float64 `json:"InstructedAmount"`
        FixedSide        string  `json:"FixedSide"`
        SellCurrency     string  `json:"SellCurrency"`
        BuyCurrency      string  `json:"BuyCurrency"`
    } `json:"QuoteRequest"`
}

func (q FXQuoteResponse) GetRate() float64 {
    if strings.HasPrefix(q.CurrencyPair, q.SellCurrency) {
        return q.ExchangeRate
    }
    return 1 / q.ExchangeRate
}

func (c *client) RequestFxQuote(ctx context.Context, payload FXQuotePayload) (data FXQuoteResponse, err error) {
    req, err := c.newRequest(ctx, http.MethodPost, "/fx/v1/quote", payload)
    if err != nil {
        return data, fmt.Errorf("failed to create request: %w", err)
    }

    req.ExpectStatus(http.StatusOK)
    req.DecodeTo(&data)
    return data, c.do(ctx, req)
}

func (c *client) ExecuteFxQuote(ctx context.Context, payload FXPayload) (err error) {
    req, err := c.newRequest(ctx, http.MethodPost, "/fx/v1/executeQuote", payload)
    if err != nil {
        return fmt.Errorf("failed to create request: %w", err)
    }

    req.ExpectStatus(http.StatusAccepted)
    return c.do(ctx, req)
}