paypal/auth.go

package paypalsdk

import (
	"bytes"
	"errors"
	"fmt"
	"net/http"
	"net/url"
	"strings"
)

// GetAuthorizationCodeURL returns URL where we need to redirect user
// After signin in PayPal get authorization_code on redirectURI
func (c *Client) GetAuthorizationCodeURL(redirectURI string, scopes []string) (string, error) {
	if redirectURI == "" {
		return "", errors.New("redirectURI cannot be empty")
	}

	if len(scopes) == 0 {
		scopes = []string{"profile", "email"}
	}

	return strings.Replace(c.APIBase, "api.", "", -1) + "/webapps/auth/protocol/openidconnect/v1/authorize?client_id=" +
		c.ClientID + "&response_type=code&scope=" + strings.Join(scopes, "+") +
		"&redirect_uri=" + redirectURI, nil
}

// GetAccessToken returns struct of TokenResponse
// Client must to get an authorization code before
// redirectURI must match with redirectURI sent to GetAuthorizationCodeURL
func (c *Client) GetAccessToken(authorizationCode string, redirectURI string) (*TokenResponse, error) {
	if authorizationCode == "" {
		return &TokenResponse{}, errors.New("authorizationCode cannot be empty")
	}
	if redirectURI == "" {
		return &TokenResponse{}, errors.New("redirectURI cannot be empty")
	}

	buf := bytes.NewBuffer([]byte("grant_type=authorization_code&code=" + url.QueryEscape(authorizationCode) + "&redirect_uri=" + url.QueryEscape(redirectURI)))
	req, err := http.NewRequest("POST", fmt.Sprintf("%s%s", c.APIBase, "/v1/identity/openidconnect/tokenservice"), buf)
	if err != nil {
		return &TokenResponse{}, err
	}

	req.SetBasicAuth(c.ClientID, c.Secret)
	req.Header.Set("Content-type", "application/x-www-form-urlencoded")

	t := TokenResponse{}
	err = c.Send(req, &t)

	// Set Token fur current Client
	if t.Token != "" {
		c.Token = &t
	}

	return &t, err
}