如何在推特上引发新事件，以便客户可以收到事件通知？
How to Raise new event on twitter so that clients can receive notification of the event?
我正在使用 LINQ to Twitter 4.1.0 检索推文，搜索特定的标签 eg.#abc。现在，只要有人在我的帐户中使用相同的标签 eg.#abc 发推文，我就会收到通知。谁能建议我怎么做？
如果您使用的是 REST API，您可以执行定期运行的搜索查询，使用 SinceID/MaxID 确保您不会搜索你已经看过的推文。它是这样工作的：
static async Task DoPagedSearchAsync(TwitterContext twitterCtx)
{
const int MaxSearchEntriesToReturn = 100;
string searchTerm = "twitter";
// oldest id you already have for this search term
ulong sinceID = 1;
// used after the first query to track current session
ulong maxID;
var combinedSearchResults = new List<Status>();
List<Status> searchResponse =
await
(from search in twitterCtx.Search
where search.Type == SearchType.Search &&
search.Query == searchTerm &&
search.Count == MaxSearchEntriesToReturn &&
search.SinceID == sinceID
select search.Statuses)
.SingleOrDefaultAsync();
combinedSearchResults.AddRange(searchResponse);
ulong previousMaxID = ulong.MaxValue;
do
{
// one less than the newest id you've just queried
maxID = searchResponse.Min(status => status.StatusID) - 1;
Debug.Assert(maxID < previousMaxID);
previousMaxID = maxID;
searchResponse =
await
(from search in twitterCtx.Search
where search.Type == SearchType.Search &&
search.Query == searchTerm &&
search.Count == MaxSearchEntriesToReturn &&
search.MaxID == maxID &&
search.SinceID == sinceID
select search.Statuses)
.SingleOrDefaultAsync();
combinedSearchResults.AddRange(searchResponse);
} while (searchResponse.Any());
combinedSearchResults.ForEach(tweet =>
Console.WriteLine(
"\n User: {0} ({1})\n Tweet: {2}",
tweet.User.ScreenNameResponse,
tweet.User.UserIDResponse,
tweet.Text));
}
在此示例中，SinceID 设置为 1 以获取自 Twitter 开始以来的所有推文。但是，您应该将其作为参数传递，之前保留了先前查询中最旧的推文 ID。
由于您没有 post 任何显示您想要的代码，我假设您在 REST API 上使用某种形式的轮询，与示例相差不大多于。但是，您也可以使用流式传输 API，其中 returns 在发布推文后几秒钟内匹配推文。下面是使用 Filter 流的示例：
static async Task DoFilterStreamAsync(TwitterContext twitterCtx)
{
Console.WriteLine("\nStreamed Content: \n");
int count = 0;
var cancelTokenSrc = new CancellationTokenSource();
try
{
await
(from strm in twitterCtx.Streaming
.WithCancellation(cancelTokenSrc.Token)
where strm.Type == StreamingType.Filter &&
strm.Track == "twitter"
select strm)
.StartAsync(async strm =>
{
await HandleStreamResponse(strm);
if (count++ >= 5)
cancelTokenSrc.Cancel();
});
}
catch (IOException ex)
{
// Twitter might have closed the stream,
// which they do sometimes. You should
// restart the stream, but be sure to
// read Twitter documentation on stream
// back-off strategies to prevent your
// app from being blocked.
Console.WriteLine(ex.ToString());
}
catch (OperationCanceledException)
{
Console.WriteLine("Stream cancelled.");
}
}
HandleStreamResponse() 是您要编写的处理通知的方法。我的建议是你使用消息队列或其他东西，这样你就不会在你使用的术语流行或获得高流量时阻止流。请快速处理消息。
如果你更喜欢响应式编程，你可以这样做：
static async Task DoRxObservableStreamAsync(TwitterContext twitterCtx)
{
Console.WriteLine("\nStreamed Content: \n");
int count = 0;
var cancelTokenSrc = new CancellationTokenSource();
try
{
var observable =
await
(from strm in twitterCtx.Streaming
.WithCancellation(cancelTokenSrc.Token)
where strm.Type == StreamingType.Filter &&
strm.Track == "twitter"
select strm)
.ToObservableAsync();
observable.Subscribe(
async strm =>
{
await HandleStreamResponse(strm);
if (count++ >= 5)
cancelTokenSrc.Cancel();
},
ex => Console.WriteLine(ex.ToString()),
() => Console.WriteLine("Completed"));
}
catch (OperationCanceledException)
{
Console.WriteLine("Stream cancelled.");
}
}
在回调和反应场景中，监控 steam 以查看它是否已关闭（例如 OperationCancelledException）。然后你必须创建一个全新的流实例到 re-start。如果发生这种情况，请跟踪您最后看到的 TweetID 并使用 REST API 搜索从那时到新流开始之间的所有推文。
更新
在每个demo中，都有一个HandleStreamResponse方法，也就是async。您可以下载 demo source code 并逐步了解它的工作原理。本质上，StreamContent 类型有一个 EntityType 属性 告诉响应是什么类型。由于源代码中的演示使用不同类型的流，因此 switch 语句说明了所有可能的消息类型。但是，在 Search 流的情况下，唯一的响应将是 StreamEntityType.Status，这将简化您的代码，因为您可以消除其他情况。知道类型后，您可以使用 as 运算符对 Entity 属性 进行转换，例如 var status = strm.Entity as Status，然后查询 status 变量属性你需要的信息。
static async Task<int> HandleStreamResponse(StreamContent strm)
{
switch (strm.EntityType)
{
case StreamEntityType.Control:
var control = strm.Entity as Control;
Console.WriteLine("Control URI: {0}", control.URL);
break;
case StreamEntityType.Delete:
var delete = strm.Entity as Delete;
Console.WriteLine("Delete - User ID: {0}, Status ID: {1}", delete.UserID, delete.StatusID);
break;
case StreamEntityType.DirectMessage:
var dm = strm.Entity as DirectMessage;
Console.WriteLine("Direct Message - Sender: {0}, Text: {1}", dm.Sender, dm.Text);
break;
case StreamEntityType.Disconnect:
var disconnect = strm.Entity as Disconnect;
Console.WriteLine("Disconnect - {0}", disconnect.Reason);
break;
case StreamEntityType.Event:
var evt = strm.Entity as Event;
Console.WriteLine("Event - Event Name: {0}", evt.EventName);
break;
case StreamEntityType.ForUser:
var user = strm.Entity as ForUser;
Console.WriteLine("For User - User ID: {0}, # Friends: {1}", user.UserID, user.Friends.Count);
break;
case StreamEntityType.FriendsList:
var friends = strm.Entity as FriendsList;
Console.WriteLine("Friends List - # Friends: {0}", friends.Friends.Count);
break;
case StreamEntityType.GeoScrub:
var scrub = strm.Entity as GeoScrub;
Console.WriteLine("GeoScrub - User ID: {0}, Up to Status ID: {1}", scrub.UserID, scrub.UpToStatusID);
break;
case StreamEntityType.Limit:
var limit = strm.Entity as Limit;
Console.WriteLine("Limit - Track: {0}", limit.Track);
break;
case StreamEntityType.Stall:
var stall = strm.Entity as Stall;
Console.WriteLine("Stall - Code: {0}, Message: {1}, % Full: {2}", stall.Code, stall.Message, stall.PercentFull);
break;
case StreamEntityType.Status:
var status = strm.Entity as Status;
Console.WriteLine("Status - @{0}: {1}", status.User.ScreenNameResponse, status.Text);
break;
case StreamEntityType.StatusWithheld:
var statusWithheld = strm.Entity as StatusWithheld;
Console.WriteLine("Status Withheld - Status ID: {0}, # Countries: {1}", statusWithheld.StatusID, statusWithheld.WithheldInCountries.Count);
break;
case StreamEntityType.TooManyFollows:
var follows = strm.Entity as TooManyFollows;
Console.WriteLine("Too Many Follows - Message: {0}", follows.Message);
break;
case StreamEntityType.UserWithheld:
var userWithheld = strm.Entity as UserWithheld;
Console.WriteLine("User Withheld - User ID: {0}, # Countries: {1}", userWithheld.UserID, userWithheld.WithheldInCountries.Count);
break;
case StreamEntityType.ParseError:
var unparsedJson = strm.Entity as string;
Console.WriteLine("Parse Error - {0}", unparsedJson);
break;
case StreamEntityType.Unknown:
default:
Console.WriteLine("Unknown - " + strm.Content + "\n");
break;
}
return await Task.FromResult(0);
}
我正在使用 LINQ to Twitter 4.1.0 检索推文，搜索特定的标签 eg.#abc。现在，只要有人在我的帐户中使用相同的标签 eg.#abc 发推文，我就会收到通知。谁能建议我怎么做？
如果您使用的是 REST API，您可以执行定期运行的搜索查询，使用 SinceID/MaxID 确保您不会搜索你已经看过的推文。它是这样工作的：
static async Task DoPagedSearchAsync(TwitterContext twitterCtx)
{
const int MaxSearchEntriesToReturn = 100;
string searchTerm = "twitter";
// oldest id you already have for this search term
ulong sinceID = 1;
// used after the first query to track current session
ulong maxID;
var combinedSearchResults = new List<Status>();
List<Status> searchResponse =
await
(from search in twitterCtx.Search
where search.Type == SearchType.Search &&
search.Query == searchTerm &&
search.Count == MaxSearchEntriesToReturn &&
search.SinceID == sinceID
select search.Statuses)
.SingleOrDefaultAsync();
combinedSearchResults.AddRange(searchResponse);
ulong previousMaxID = ulong.MaxValue;
do
{
// one less than the newest id you've just queried
maxID = searchResponse.Min(status => status.StatusID) - 1;
Debug.Assert(maxID < previousMaxID);
previousMaxID = maxID;
searchResponse =
await
(from search in twitterCtx.Search
where search.Type == SearchType.Search &&
search.Query == searchTerm &&
search.Count == MaxSearchEntriesToReturn &&
search.MaxID == maxID &&
search.SinceID == sinceID
select search.Statuses)
.SingleOrDefaultAsync();
combinedSearchResults.AddRange(searchResponse);
} while (searchResponse.Any());
combinedSearchResults.ForEach(tweet =>
Console.WriteLine(
"\n User: {0} ({1})\n Tweet: {2}",
tweet.User.ScreenNameResponse,
tweet.User.UserIDResponse,
tweet.Text));
}
在此示例中，SinceID 设置为 1 以获取自 Twitter 开始以来的所有推文。但是，您应该将其作为参数传递，之前保留了先前查询中最旧的推文 ID。
由于您没有 post 任何显示您想要的代码，我假设您在 REST API 上使用某种形式的轮询，与示例相差不大多于。但是，您也可以使用流式传输 API，其中 returns 在发布推文后几秒钟内匹配推文。下面是使用 Filter 流的示例：
static async Task DoFilterStreamAsync(TwitterContext twitterCtx)
{
Console.WriteLine("\nStreamed Content: \n");
int count = 0;
var cancelTokenSrc = new CancellationTokenSource();
try
{
await
(from strm in twitterCtx.Streaming
.WithCancellation(cancelTokenSrc.Token)
where strm.Type == StreamingType.Filter &&
strm.Track == "twitter"
select strm)
.StartAsync(async strm =>
{
await HandleStreamResponse(strm);
if (count++ >= 5)
cancelTokenSrc.Cancel();
});
}
catch (IOException ex)
{
// Twitter might have closed the stream,
// which they do sometimes. You should
// restart the stream, but be sure to
// read Twitter documentation on stream
// back-off strategies to prevent your
// app from being blocked.
Console.WriteLine(ex.ToString());
}
catch (OperationCanceledException)
{
Console.WriteLine("Stream cancelled.");
}
}
HandleStreamResponse() 是您要编写的处理通知的方法。我的建议是你使用消息队列或其他东西，这样你就不会在你使用的术语流行或获得高流量时阻止流。请快速处理消息。
如果你更喜欢响应式编程，你可以这样做：
static async Task DoRxObservableStreamAsync(TwitterContext twitterCtx)
{
Console.WriteLine("\nStreamed Content: \n");
int count = 0;
var cancelTokenSrc = new CancellationTokenSource();
try
{
var observable =
await
(from strm in twitterCtx.Streaming
.WithCancellation(cancelTokenSrc.Token)
where strm.Type == StreamingType.Filter &&
strm.Track == "twitter"
select strm)
.ToObservableAsync();
observable.Subscribe(
async strm =>
{
await HandleStreamResponse(strm);
if (count++ >= 5)
cancelTokenSrc.Cancel();
},
ex => Console.WriteLine(ex.ToString()),
() => Console.WriteLine("Completed"));
}
catch (OperationCanceledException)
{
Console.WriteLine("Stream cancelled.");
}
}
在回调和反应场景中，监控 steam 以查看它是否已关闭（例如 OperationCancelledException）。然后你必须创建一个全新的流实例到 re-start。如果发生这种情况，请跟踪您最后看到的 TweetID 并使用 REST API 搜索从那时到新流开始之间的所有推文。
更新
在每个demo中，都有一个HandleStreamResponse方法，也就是async。您可以下载 demo source code 并逐步了解它的工作原理。本质上，StreamContent 类型有一个 EntityType 属性 告诉响应是什么类型。由于源代码中的演示使用不同类型的流，因此 switch 语句说明了所有可能的消息类型。但是，在 Search 流的情况下，唯一的响应将是 StreamEntityType.Status，这将简化您的代码，因为您可以消除其他情况。知道类型后，您可以使用 as 运算符对 Entity 属性 进行转换，例如 var status = strm.Entity as Status，然后查询 status 变量属性你需要的信息。
static async Task<int> HandleStreamResponse(StreamContent strm)
{
switch (strm.EntityType)
{
case StreamEntityType.Control:
var control = strm.Entity as Control;
Console.WriteLine("Control URI: {0}", control.URL);
break;
case StreamEntityType.Delete:
var delete = strm.Entity as Delete;
Console.WriteLine("Delete - User ID: {0}, Status ID: {1}", delete.UserID, delete.StatusID);
break;
case StreamEntityType.DirectMessage:
var dm = strm.Entity as DirectMessage;
Console.WriteLine("Direct Message - Sender: {0}, Text: {1}", dm.Sender, dm.Text);
break;
case StreamEntityType.Disconnect:
var disconnect = strm.Entity as Disconnect;
Console.WriteLine("Disconnect - {0}", disconnect.Reason);
break;
case StreamEntityType.Event:
var evt = strm.Entity as Event;
Console.WriteLine("Event - Event Name: {0}", evt.EventName);
break;
case StreamEntityType.ForUser:
var user = strm.Entity as ForUser;
Console.WriteLine("For User - User ID: {0}, # Friends: {1}", user.UserID, user.Friends.Count);
break;
case StreamEntityType.FriendsList:
var friends = strm.Entity as FriendsList;
Console.WriteLine("Friends List - # Friends: {0}", friends.Friends.Count);
break;
case StreamEntityType.GeoScrub:
var scrub = strm.Entity as GeoScrub;
Console.WriteLine("GeoScrub - User ID: {0}, Up to Status ID: {1}", scrub.UserID, scrub.UpToStatusID);
break;
case StreamEntityType.Limit:
var limit = strm.Entity as Limit;
Console.WriteLine("Limit - Track: {0}", limit.Track);
break;
case StreamEntityType.Stall:
var stall = strm.Entity as Stall;
Console.WriteLine("Stall - Code: {0}, Message: {1}, % Full: {2}", stall.Code, stall.Message, stall.PercentFull);
break;
case StreamEntityType.Status:
var status = strm.Entity as Status;
Console.WriteLine("Status - @{0}: {1}", status.User.ScreenNameResponse, status.Text);
break;
case StreamEntityType.StatusWithheld:
var statusWithheld = strm.Entity as StatusWithheld;
Console.WriteLine("Status Withheld - Status ID: {0}, # Countries: {1}", statusWithheld.StatusID, statusWithheld.WithheldInCountries.Count);
break;
case StreamEntityType.TooManyFollows:
var follows = strm.Entity as TooManyFollows;
Console.WriteLine("Too Many Follows - Message: {0}", follows.Message);
break;
case StreamEntityType.UserWithheld:
var userWithheld = strm.Entity as UserWithheld;
Console.WriteLine("User Withheld - User ID: {0}, # Countries: {1}", userWithheld.UserID, userWithheld.WithheldInCountries.Count);
break;
case StreamEntityType.ParseError:
var unparsedJson = strm.Entity as string;
Console.WriteLine("Parse Error - {0}", unparsedJson);
break;
case StreamEntityType.Unknown:
default:
Console.WriteLine("Unknown - " + strm.Content + "\n");
break;
}
return await Task.FromResult(0);
}