/
TwitterDataProvider.cs
849 lines (719 loc) · 32.5 KB
/
TwitterDataProvider.cs
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// ******************************************************************
// Copyright (c) Microsoft. All rights reserved.
// This code is licensed under the MIT License (MIT).
// THE CODE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH
// THE CODE OR THE USE OR OTHER DEALINGS IN THE CODE.
// ******************************************************************
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Runtime.InteropServices.WindowsRuntime;
using System.Threading.Tasks;
using Microsoft.Toolkit.Services.Exceptions;
using Newtonsoft.Json;
using Windows.Security.Authentication.Web;
using Windows.Security.Credentials;
using Windows.Security.Cryptography;
using Windows.Security.Cryptography.Core;
using Windows.Storage;
using Windows.Storage.Streams;
namespace Microsoft.Toolkit.Uwp.Services.Twitter
{
/// <summary>
/// Data Provider for connecting to Twitter service.
/// </summary>
public class TwitterDataProvider : Toolkit.Services.DataProviderBase<TwitterDataConfig, Toolkit.Parsers.SchemaBase>
{
/// <summary>
/// Base Url for service.
/// </summary>
private const string BaseUrl = "https://api.twitter.com/1.1";
private const string OAuthBaseUrl = "https://api.twitter.com/oauth";
private const string PublishUrl = "https://upload.twitter.com/1.1";
private const string UserStreamUrl = "https://userstream.twitter.com/1.1";
private static HttpClient _client;
/// <summary>
/// Base Url for service.
/// </summary>
private readonly TwitterOAuthTokens _tokens;
/// <summary>
/// Password vault used to store access tokens
/// </summary>
private readonly PasswordVault _vault;
private TwitterOAuthRequest _streamRequest;
/// <summary>
/// Gets or sets logged in user information.
/// </summary>
public string UserScreenName { get; set; }
/// <summary>
/// Gets a value indicating whether the provider is already logged in
/// </summary>
public bool LoggedIn { get; private set; }
/// <summary>
/// Initializes a new instance of the <see cref="TwitterDataProvider"/> class.
/// Constructor.
/// </summary>
/// <param name="tokens">OAuth tokens for request.</param>
public TwitterDataProvider(TwitterOAuthTokens tokens)
{
_tokens = tokens;
_vault = new PasswordVault();
if (_client == null)
{
HttpClientHandler handler = new HttpClientHandler();
handler.AutomaticDecompression = DecompressionMethods.GZip;
_client = new HttpClient(handler);
}
}
/// <summary>
/// Retrieve user data.
/// </summary>
/// <param name="screenName">User screen name or null for current logged user</param>
/// <returns>Returns user data.</returns>
public async Task<TwitterUser> GetUserAsync(string screenName = null)
{
string rawResult = null;
try
{
var userScreenName = screenName ?? UserScreenName;
var uri = new Uri($"{BaseUrl}/users/show.json?screen_name={userScreenName}");
TwitterOAuthRequest request = new TwitterOAuthRequest();
rawResult = await request.ExecuteGetAsync(uri, _tokens);
return JsonConvert.DeserializeObject<TwitterUser>(rawResult);
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if (response.StatusCode == HttpStatusCode.NotFound)
{
throw new UserNotFoundException(screenName);
}
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
catch
{
if (!string.IsNullOrEmpty(rawResult))
{
var errors = JsonConvert.DeserializeObject<TwitterErrors>(rawResult);
throw new TwitterException { Errors = errors };
}
throw;
}
}
/// <summary>
/// Retrieve user timeline data with specific parser.
/// </summary>
/// <typeparam name="TSchema">Strong type for results.</typeparam>
/// <param name="screenName">User screen name.</param>
/// <param name="maxRecords">Upper record limit.</param>
/// <param name="parser">Specific results parser.</param>
/// <returns>Returns strongly typed list of results.</returns>
public async Task<IEnumerable<TSchema>> GetUserTimeLineAsync<TSchema>(string screenName, int maxRecords, Toolkit.Parsers.IParser<TSchema> parser)
where TSchema : Toolkit.Parsers.SchemaBase
{
string rawResult = null;
try
{
var uri = new Uri($"{BaseUrl}/statuses/user_timeline.json?screen_name={screenName}&count={maxRecords}&include_rts=1");
TwitterOAuthRequest request = new TwitterOAuthRequest();
rawResult = await request.ExecuteGetAsync(uri, _tokens);
var result = parser.Parse(rawResult);
return result
.Take(maxRecords)
.ToList();
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if (response.StatusCode == HttpStatusCode.NotFound)
{
throw new UserNotFoundException(screenName);
}
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
catch
{
if (!string.IsNullOrEmpty(rawResult))
{
var errors = JsonConvert.DeserializeObject<TwitterErrors>(rawResult);
throw new TwitterException { Errors = errors };
}
throw;
}
}
/// <summary>
/// Search for specific hash tag with specific parser.
/// </summary>
/// <typeparam name="TSchema">Strong type for results.</typeparam>
/// <param name="hashTag">Hash tag.</param>
/// <param name="maxRecords">Upper record limit.</param>
/// <param name="parser">Specific results parser.</param>
/// <returns>Returns strongly typed list of results.</returns>
public async Task<IEnumerable<TSchema>> SearchAsync<TSchema>(string hashTag, int maxRecords, Toolkit.Parsers.IParser<TSchema> parser)
where TSchema : Toolkit.Parsers.SchemaBase
{
try
{
var uri = new Uri($"{BaseUrl}/search/tweets.json?q={Uri.EscapeDataString(hashTag)}&count={maxRecords}");
TwitterOAuthRequest request = new TwitterOAuthRequest();
var rawResult = await request.ExecuteGetAsync(uri, _tokens);
var result = parser.Parse(rawResult);
return result
.Take(maxRecords)
.ToList();
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
}
private PasswordCredential PasswordCredential
{
get
{
// Password vault remains when app is uninstalled so checking the local settings value
if (ApplicationData.Current.LocalSettings.Values["TwitterScreenName"] == null)
{
return null;
}
var passwordCredentials = _vault.RetrieveAll();
var temp = passwordCredentials.FirstOrDefault(c => c.Resource == "TwitterAccessToken");
if (temp == null)
{
return null;
}
return _vault.Retrieve(temp.Resource, temp.UserName);
}
}
/// <summary>
/// Log user in to Twitter.
/// </summary>
/// <returns>Boolean indicating login success.</returns>
public async Task<bool> LoginAsync()
{
var twitterCredentials = PasswordCredential;
if (twitterCredentials != null)
{
_tokens.AccessToken = twitterCredentials.UserName;
_tokens.AccessTokenSecret = twitterCredentials.Password;
UserScreenName = ApplicationData.Current.LocalSettings.Values["TwitterScreenName"].ToString();
LoggedIn = true;
return true;
}
if (await InitializeRequestAccessTokensAsync(_tokens.CallbackUri) == false)
{
LoggedIn = false;
return false;
}
string requestToken = _tokens.RequestToken;
string twitterUrl = $"{OAuthBaseUrl}/authorize?oauth_token={requestToken}";
Uri startUri = new Uri(twitterUrl);
Uri endUri = new Uri(_tokens.CallbackUri);
var result = await WebAuthenticationBroker.AuthenticateAsync(WebAuthenticationOptions.None, startUri, endUri);
switch (result.ResponseStatus)
{
case WebAuthenticationStatus.Success:
LoggedIn = true;
return await ExchangeRequestTokenForAccessTokenAsync(result.ResponseData);
case WebAuthenticationStatus.ErrorHttp:
Debug.WriteLine("WAB failed, message={0}", result.ResponseErrorDetail.ToString());
LoggedIn = false;
return false;
case WebAuthenticationStatus.UserCancel:
Debug.WriteLine("WAB user aborted.");
LoggedIn = false;
return false;
}
LoggedIn = false;
return false;
}
/// <summary>
/// Log user out of Twitter.
/// </summary>
public void Logout()
{
var twitterCredentials = PasswordCredential;
if (twitterCredentials != null)
{
_vault.Remove(twitterCredentials);
ApplicationData.Current.LocalSettings.Values["TwitterScreenName"] = null;
UserScreenName = null;
}
LoggedIn = false;
}
/// <summary>
/// Tweets a status update.
/// </summary>
/// <param name="tweet">Tweet text.</param>
/// <param name="pictures">Pictures to attach to the tweet (up to 4).</param>
/// <returns>Success or failure.</returns>
public async Task<bool> TweetStatusAsync(string tweet, params IRandomAccessStream[] pictures)
{
return await TweetStatusAsync(new TwitterStatus { Message = tweet }, pictures);
}
/// <summary>
/// Tweets a status update.
/// </summary>
/// <param name="status">Tweet text.</param>
/// <param name="pictures">Pictures to attach to the tweet (up to 4).</param>
/// <returns>Success or failure.</returns>
public async Task<bool> TweetStatusAsync(TwitterStatus status, params IRandomAccessStream[] pictures)
{
try
{
var mediaIds = string.Empty;
if (pictures != null && pictures.Length > 0)
{
var ids = new List<string>();
foreach (var picture in pictures)
{
ids.Add(await UploadPictureAsync(picture));
}
mediaIds = "&media_ids=" + string.Join(",", ids);
}
var uri = new Uri($"{BaseUrl}/statuses/update.json?{status.RequestParameters}{mediaIds}");
TwitterOAuthRequest request = new TwitterOAuthRequest();
await request.ExecutePostAsync(uri, _tokens);
return true;
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
}
/// <summary>
/// Open a connection to user streams service (Events, DirectMessages...).
/// </summary>
/// <param name="parser">Specific stream's result parser.</param>
/// <param name="callback">Method invoked each time a result occurs.</param>
/// <returns>Awaitable task.</returns>
public Task StartUserStreamAsync(TwitterUserStreamParser parser, TwitterStreamCallbacks.TwitterStreamCallback callback)
{
try
{
var uri = new Uri($"{UserStreamUrl}/user.json?replies=all");
_streamRequest = new TwitterOAuthRequest();
return _streamRequest.ExecuteGetStreamAsync(uri, _tokens, rawResult => callback(parser.Parse(rawResult)));
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
}
/// <summary>
/// Stop user's stream
/// </summary>
public void StopStream()
{
_streamRequest?.Abort();
_streamRequest = null;
}
/// <summary>
/// Publish a picture to Twitter user's medias.
/// </summary>
/// <param name="stream">Picture stream.</param>
/// <returns>Media ID</returns>
public async Task<string> UploadPictureAsync(IRandomAccessStream stream)
{
var uri = new Uri($"{PublishUrl}/media/upload.json");
// Get picture data
var fileBytes = new byte[stream.Size];
await stream.ReadAsync(fileBytes.AsBuffer(), (uint)stream.Size, InputStreamOptions.None);
stream.Seek(0);
string boundary = DateTime.Now.Ticks.ToString("x");
TwitterOAuthRequest request = new TwitterOAuthRequest();
return await request.ExecutePostMultipartAsync(uri, _tokens, boundary, fileBytes);
}
/// <summary>
/// Returns parser implementation for specified configuration.
/// </summary>
/// <param name="config">Query configuration.</param>
/// <returns>Strongly typed parser.</returns>
protected override Toolkit.Parsers.IParser<Toolkit.Parsers.SchemaBase> GetDefaultParser(TwitterDataConfig config)
{
if (config == null)
{
throw new ConfigNullException();
}
switch (config.QueryType)
{
case TwitterQueryType.Search:
return new TwitterSearchParser();
case TwitterQueryType.Home:
case TwitterQueryType.User:
case TwitterQueryType.Custom:
return new TwitterParser<Toolkit.Parsers.SchemaBase>();
default:
return new TwitterParser<Toolkit.Parsers.SchemaBase>();
}
}
/// <summary>
/// Wrapper around REST API for making data request.
/// </summary>
/// <typeparam name="TSchema">Schema to use</typeparam>
/// <param name="config">Query configuration.</param>
/// <param name="maxRecords">Upper limit for records returned.</param>
/// <param name="pageIndex">The zero-based index of the page that corresponds to the items to retrieve.</param>
/// <param name="parser">IParser implementation for interpreting results.</param>
/// <returns>Strongly typed list of results.</returns>
protected override async Task<IEnumerable<TSchema>> GetDataAsync<TSchema>(TwitterDataConfig config, int maxRecords, int pageIndex, Toolkit.Parsers.IParser<TSchema> parser)
{
IEnumerable<TSchema> items;
switch (config.QueryType)
{
case TwitterQueryType.User:
items = await GetUserTimeLineAsync(config.Query, maxRecords, parser);
break;
case TwitterQueryType.Search:
items = await SearchAsync(config.Query, maxRecords, parser);
break;
case TwitterQueryType.Custom:
items = await GetCustomSearch(config.Query, parser);
break;
case TwitterQueryType.Home:
default:
items = await GetHomeTimeLineAsync(maxRecords, parser);
break;
}
return items;
}
/// <summary>
/// Check validity of configuration.
/// </summary>
/// <param name="config">Query configuration.</param>
protected override void ValidateConfig(TwitterDataConfig config)
{
if (config?.Query == null && config?.QueryType != TwitterQueryType.Home)
{
throw new ConfigParameterNullException(nameof(config.Query));
}
if (_tokens == null)
{
throw new ConfigParameterNullException(nameof(_tokens));
}
if (string.IsNullOrEmpty(_tokens.ConsumerKey))
{
throw new OAuthKeysNotPresentException(nameof(_tokens.ConsumerKey));
}
if (string.IsNullOrEmpty(_tokens.ConsumerSecret))
{
throw new OAuthKeysNotPresentException(nameof(_tokens.ConsumerSecret));
}
}
/// <summary>
/// Extract requested token from the REST API response string.
/// </summary>
/// <param name="getResponse">REST API response string.</param>
/// <param name="tokenType">Token type to retrieve.</param>
/// <returns>Required token.</returns>
private static string ExtractTokenFromResponse(string getResponse, TwitterOAuthTokenType tokenType)
{
string requestOrAccessToken = null;
string requestOrAccessTokenSecret = null;
string oauthVerifier = null;
string oauthCallbackConfirmed = null;
string screenName = null;
string[] keyValPairs = getResponse.Split('&');
for (int i = 0; i < keyValPairs.Length; i++)
{
string[] splits = keyValPairs[i].Split('=');
switch (splits[0])
{
case "screen_name":
screenName = splits[1];
break;
case "oauth_token":
requestOrAccessToken = splits[1];
break;
case "oauth_token_secret":
requestOrAccessTokenSecret = splits[1];
break;
case "oauth_callback_confirmed":
oauthCallbackConfirmed = splits[1];
break;
case "oauth_verifier":
oauthVerifier = splits[1];
break;
}
}
switch (tokenType)
{
case TwitterOAuthTokenType.OAuthRequestOrAccessToken:
return requestOrAccessToken;
case TwitterOAuthTokenType.OAuthRequestOrAccessTokenSecret:
return requestOrAccessTokenSecret;
case TwitterOAuthTokenType.OAuthVerifier:
return oauthVerifier;
case TwitterOAuthTokenType.ScreenName:
return screenName;
case TwitterOAuthTokenType.OAuthCallbackConfirmed:
return oauthCallbackConfirmed;
}
return string.Empty;
}
/// <summary>
/// Get home time line data.
/// </summary>
/// <typeparam name="TSchema">Strong typed result.</typeparam>
/// <param name="maxRecords">Upper record limit.</param>
/// <param name="parser">Specific result parser.</param>
/// <returns>Return strong typed list of results.</returns>
private async Task<IEnumerable<TSchema>> GetHomeTimeLineAsync<TSchema>(int maxRecords, Toolkit.Parsers.IParser<TSchema> parser)
where TSchema : Toolkit.Parsers.SchemaBase
{
try
{
var uri = new Uri($"{BaseUrl}/statuses/home_timeline.json?count={maxRecords}");
TwitterOAuthRequest request = new TwitterOAuthRequest();
var rawResult = await request.ExecuteGetAsync(uri, _tokens);
return parser.Parse(rawResult);
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
}
private async Task<IEnumerable<TSchema>> GetCustomSearch<TSchema>(string query, Toolkit.Parsers.IParser<TSchema> parser)
where TSchema : Toolkit.Parsers.SchemaBase
{
try
{
var uri = new Uri($"{BaseUrl}/{query}");
TwitterOAuthRequest request = new TwitterOAuthRequest();
var rawResult = await request.ExecuteGetAsync(uri, _tokens);
return parser.Parse(rawResult);
}
catch (WebException wex)
{
HttpWebResponse response = wex.Response as HttpWebResponse;
if (response != null)
{
if ((int)response.StatusCode == 429)
{
throw new TooManyRequestsException();
}
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
throw new OAuthKeysRevokedException();
}
}
throw;
}
}
/// <summary>
/// Package up token request.
/// </summary>
/// <param name="twitterCallbackUrl">Callback Uri.</param>
/// <returns>Success or failure.</returns>
private async Task<bool> InitializeRequestAccessTokensAsync(string twitterCallbackUrl)
{
var twitterUrl = $"{OAuthBaseUrl}/request_token";
string nonce = GetNonce();
string timeStamp = GetTimeStamp();
string sigBaseStringParams = GetSignatureBaseStringParams(_tokens.ConsumerKey, nonce, timeStamp, "oauth_callback=" + Uri.EscapeDataString(twitterCallbackUrl));
string sigBaseString = "GET&" + Uri.EscapeDataString(twitterUrl) + "&" + Uri.EscapeDataString(sigBaseStringParams);
string signature = GetSignature(sigBaseString, _tokens.ConsumerSecret);
twitterUrl += "?" + sigBaseStringParams + "&oauth_signature=" + Uri.EscapeDataString(signature);
string getResponse;
using (var request = new HttpRequestMessage(HttpMethod.Get, new Uri(twitterUrl)))
{
using (var response = await _client.SendAsync(request).ConfigureAwait(false))
{
var data = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
if (response.IsSuccessStatusCode)
{
getResponse = data;
}
else
{
Debug.WriteLine("HttpHelper call failed trying to retrieve Twitter Request Tokens. Message: {0}", data);
return false;
}
}
}
var callbackConfirmed = ExtractTokenFromResponse(getResponse, TwitterOAuthTokenType.OAuthCallbackConfirmed);
if (Convert.ToBoolean(callbackConfirmed) != true)
{
return false;
}
_tokens.RequestToken = ExtractTokenFromResponse(getResponse, TwitterOAuthTokenType.OAuthRequestOrAccessToken);
_tokens.RequestTokenSecret = ExtractTokenFromResponse(getResponse, TwitterOAuthTokenType.OAuthRequestOrAccessTokenSecret);
return true;
}
/// <summary>
/// Build signature base string.
/// </summary>
/// <param name="consumerKey">Consumer Key.</param>
/// <param name="nonce">Nonce.</param>
/// <param name="timeStamp">Timestamp.</param>
/// <param name="additionalParameters">Any additional parameter name/values that need appending to base string.</param>
/// <returns>Signature base string.</returns>
private string GetSignatureBaseStringParams(string consumerKey, string nonce, string timeStamp, string additionalParameters = "")
{
string sigBaseStringParams = additionalParameters;
sigBaseStringParams += "&" + "oauth_consumer_key=" + consumerKey;
sigBaseStringParams += "&" + "oauth_nonce=" + nonce;
sigBaseStringParams += "&" + "oauth_signature_method=HMAC-SHA1";
sigBaseStringParams += "&" + "oauth_timestamp=" + timeStamp;
sigBaseStringParams += "&" + "oauth_version=1.0";
return sigBaseStringParams;
}
/// <summary>
/// Extract and initialize access tokens.
/// </summary>
/// <param name="webAuthResultResponseData">WAB data containing appropriate tokens.</param>
/// <returns>Success or failure.</returns>
private async Task<bool> ExchangeRequestTokenForAccessTokenAsync(string webAuthResultResponseData)
{
string responseData = webAuthResultResponseData.Substring(webAuthResultResponseData.IndexOf("oauth_token"));
string requestToken = ExtractTokenFromResponse(responseData, TwitterOAuthTokenType.OAuthRequestOrAccessToken);
// Ensure requestToken matches accessToken per Twitter documentation.
if (requestToken != _tokens.RequestToken)
{
return false;
}
string oAuthVerifier = ExtractTokenFromResponse(responseData, TwitterOAuthTokenType.OAuthVerifier);
string twitterUrl = $"{OAuthBaseUrl}/access_token";
string timeStamp = GetTimeStamp();
string nonce = GetNonce();
string sigBaseStringParams = GetSignatureBaseStringParams(_tokens.ConsumerKey, nonce, timeStamp, "oauth_token=" + requestToken);
string sigBaseString = "POST&";
sigBaseString += Uri.EscapeDataString(twitterUrl) + "&" + Uri.EscapeDataString(sigBaseStringParams);
string signature = GetSignature(sigBaseString, _tokens.ConsumerSecret);
string data = null;
string authorizationHeaderParams = "oauth_consumer_key=\"" + _tokens.ConsumerKey + "\", oauth_nonce=\"" + nonce + "\", oauth_signature_method=\"HMAC-SHA1\", oauth_signature=\"" + Uri.EscapeDataString(signature) + "\", oauth_timestamp=\"" + timeStamp + "\", oauth_token=\"" + Uri.EscapeDataString(requestToken) + "\", oauth_verifier=\"" + Uri.EscapeUriString(oAuthVerifier) + "\" , oauth_version=\"1.0\"";
using (var request = new HttpRequestMessage(HttpMethod.Post, new Uri(twitterUrl)))
{
request.Headers.Authorization = new AuthenticationHeaderValue("OAuth", authorizationHeaderParams);
using (var response = await _client.SendAsync(request).ConfigureAwait(false))
{
data = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
}
}
var screenName = ExtractTokenFromResponse(data, TwitterOAuthTokenType.ScreenName);
var accessToken = ExtractTokenFromResponse(data, TwitterOAuthTokenType.OAuthRequestOrAccessToken);
var accessTokenSecret = ExtractTokenFromResponse(data, TwitterOAuthTokenType.OAuthRequestOrAccessTokenSecret);
UserScreenName = screenName;
_tokens.AccessToken = accessToken;
_tokens.AccessTokenSecret = accessTokenSecret;
var passwordCredential = new PasswordCredential("TwitterAccessToken", accessToken, accessTokenSecret);
ApplicationData.Current.LocalSettings.Values["TwitterScreenName"] = screenName;
_vault.Add(passwordCredential);
return true;
}
/// <summary>
/// Generate nonce.
/// </summary>
/// <returns>Nonce.</returns>
private string GetNonce()
{
Random rand = new Random();
int nonce = rand.Next(1000000000);
return nonce.ToString();
}
/// <summary>
/// Generate timestamp.
/// </summary>
/// <returns>Timestamp.</returns>
private string GetTimeStamp()
{
TimeSpan sinceEpoch = DateTime.UtcNow - new DateTime(1970, 1, 1);
return Math.Round(sinceEpoch.TotalSeconds).ToString();
}
/// <summary>
/// Generate request signature.
/// </summary>
/// <param name="sigBaseString">Base string.</param>
/// <param name="consumerSecretKey">Consumer secret key.</param>
/// <returns>Signature.</returns>
private string GetSignature(string sigBaseString, string consumerSecretKey)
{
IBuffer keyMaterial = CryptographicBuffer.ConvertStringToBinary(consumerSecretKey + "&", BinaryStringEncoding.Utf8);
MacAlgorithmProvider hmacSha1Provider = MacAlgorithmProvider.OpenAlgorithm("HMAC_SHA1");
CryptographicKey macKey = hmacSha1Provider.CreateKey(keyMaterial);
IBuffer dataToBeSigned = CryptographicBuffer.ConvertStringToBinary(sigBaseString, BinaryStringEncoding.Utf8);
IBuffer signatureBuffer = CryptographicEngine.Sign(macKey, dataToBeSigned);
string signature = CryptographicBuffer.EncodeToBase64String(signatureBuffer);
return signature;
}
}
}