OpenTween/Api/BitlyApi.cs

   1 // OpenTween - Client of Twitter
   2 // Copyright (c) 2017 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
   3 // All rights reserved.
   4 //
   5 // This file is part of OpenTween.
   6 //
   7 // This program is free software; you can redistribute it and/or modify it
   8 // under the terms of the GNU General Public License as published by the Free
   9 // Software Foundation; either version 3 of the License, or (at your option)
  10 // any later version.
  11 //
  12 // This program is distributed in the hope that it will be useful, but
  13 // WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14 // or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  15 // for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License along
  18 // with this program. If not, see <http://www.gnu.org/licenses/>, or write to
  19 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
  20 // Boston, MA 02110-1301, USA.
  21
  22 using System;
  23 using System.Collections.Generic;
  24 using System.Linq;
  25 using System.Net.Http;
  26 using System.Net.Http.Headers;
  27 using System.Runtime.Serialization.Json;
  28 using System.Text;
  29 using System.Text.RegularExpressions;
  30 using System.Threading.Tasks;
  31 using System.Xml;
  32 using System.Xml.Linq;
  33 using OpenTween.Connection;
  34
  35 namespace OpenTween.Api
  36 {
  37     public class BitlyApi
  38     {
  39         public static readonly Uri ApiBase = new Uri("https://api-ssl.bitly.com/");
  40
  41         public string EndUserAccessToken { get; set; }
  42
  43         public string EndUserLoginName { get; set; }
  44         public string EndUserApiKey { get; set; }
  45
  46         private HttpClient http => this.localHttpClient ?? Networking.Http;
  47         private readonly HttpClient localHttpClient;
  48
  49         public BitlyApi()
  50             : this(null)
  51         {
  52         }
  53
  54         public BitlyApi(HttpClient http)
  55             => this.localHttpClient = http;
  56
  57         public async Task<Uri> ShortenAsync(Uri srcUri, string domain = null)
  58         {
  59             var query = new Dictionary<string, string>
  60             {
  61                 ["format"] = "txt",
  62                 ["longUrl"] = srcUri.OriginalString,
  63             };
  64
  65             if (!string.IsNullOrEmpty(domain))
  66                 query["domain"] = domain;
  67
  68             var uri = new Uri("/v3/shorten", UriKind.Relative);
  69             var responseText = await this.GetAsync(uri, query).ConfigureAwait(false);
  70
  71             if (!Regex.IsMatch(responseText, @"^https?://"))
  72                 throw new WebApiException("Failed to create URL.", responseText);
  73
  74             return new Uri(responseText.TrimEnd());
  75         }
  76
  77         public async Task<string> GetAsync(Uri endpoint, IEnumerable<KeyValuePair<string, string>> param)
  78         {
  79             var paramWithToken = param.Concat(this.CreateAccessTokenParams());
  80
  81             var requestUri = new Uri(new Uri(ApiBase, endpoint), "?" + MyCommon.BuildQueryString(paramWithToken));
  82
  83             using (var request = new HttpRequestMessage(HttpMethod.Get, requestUri))
  84             using (var response = await this.http.SendAsync(request).ConfigureAwait(false))
  85             {
  86                 return await response.Content.ReadAsStringAsync()
  87                     .ConfigureAwait(false);
  88             }
  89         }
  90
  91         public async Task<string> GetAccessTokenAsync(string username, string password)
  92         {
  93             var param = new Dictionary<string, string>
  94             {
  95                 ["grant_type"] = "password",
  96                 ["username"] = username,
  97                 ["password"] = password,
  98             };
  99
 100             var endpoint = new Uri(ApiBase, "/oauth/access_token");
 101
 102             using (var request = new HttpRequestMessage(HttpMethod.Post, endpoint))
 103             using (var postContent = new FormUrlEncodedContent(param))
 104             {
 105                 var authzParam = ApplicationSettings.BitlyClientId + ":" + ApplicationSettings.BitlyClientSecret;
 106                 request.Headers.Authorization = new AuthenticationHeaderValue("Basic", Convert.ToBase64String(Encoding.UTF8.GetBytes(authzParam)));
 107
 108                 request.Content = postContent;
 109
 110                 using (var response = await this.http.SendAsync(request).ConfigureAwait(false))
 111                 {
 112                     var responseBytes = await response.Content.ReadAsByteArrayAsync()
 113                         .ConfigureAwait(false);
 114
 115                     return this.ParseOAuthCredential(responseBytes);
 116                 }
 117             }
 118         }
 119
 120         private string ParseOAuthCredential(byte[] responseBytes)
 121         {
 122             using (var jsonReader = JsonReaderWriterFactory.CreateJsonReader(responseBytes, XmlDictionaryReaderQuotas.Max))
 123             {
 124                 var xElm = XElement.Load(jsonReader);
 125
 126                 var statusCode = xElm.Element("status_code")?.Value ?? "200";
 127                 if (statusCode != "200")
 128                 {
 129                     var statusText = xElm.Element("status_txt")?.Value;
 130                     throw new WebApiException(statusText ?? $"status_code = {statusCode}");
 131                 }
 132
 133                 var accessToken = xElm.Element("access_token")?.Value;
 134                 if (accessToken == null)
 135                     throw new WebApiException("Property `access_token` required");
 136
 137                 return accessToken;
 138             }
 139         }
 140
 141         private IEnumerable<KeyValuePair<string, string>> CreateAccessTokenParams()
 142         {
 143             if (string.IsNullOrEmpty(this.EndUserAccessToken))
 144             {
 145                 return new[]
 146                 {
 147                     new KeyValuePair<string, string>("login", this.EndUserLoginName),
 148                     new KeyValuePair<string, string>("apiKey", this.EndUserApiKey),
 149                 };
 150             }
 151
 152             return new[]
 153             {
 154                 new KeyValuePair<string, string>("access_token", this.EndUserAccessToken),
 155             };
 156         }
 157     }
 158 }