Add SetTransactionContext function

Author: xiongdi9456

stc.go

@@ -0,0 +1,31 @@
+package paypal
+
+import (
+	"context"
+	"fmt"
+)
+
+// SetTransactionContext
+// PayPal partners and merchants can Set transaction context to send additional data about a customer to PayPal before the customer transaction is processed.
+// PayPal uses this data to complete a pre-transaction risk management evaluation
+// Endpoint: PUT <endpoint>/v1/risk/transaction-contexts/<merchant_id>/<tracking_id>
+func (c *Client) SetTransactionContext(ctx context.Context, merchantID, orderID string, tcPayload interface{}) error {
+
+	if merchantID == "" || orderID == "" {
+		return fmt.Errorf("paypal: merchantID or orderID is empty")
+	}
+
+	url := fmt.Sprintf("%s%s%s", c.APIBase, "/v1/risk/transaction-contexts/", merchantID+"/"+orderID)
+
+	req, err := c.NewRequest(ctx, "PUT", url, tcPayload)
+
+	if err != nil {
+		return err
+	}
+
+	if err = c.SendWithAuth(req, nil); err != nil {
+		return err
+	}
+
+	return nil
+}