/// <summary>
/// Post the message msg to the slack channel implied by the webhook.
/// </summary>
/// <param name="log">Logger instance.</param>
/// <param name="msg"> Message to be posted.</param>
/// <returns>Status code: 0 = success.</returns>
public static async Task <int> PostSlackMessageAsync(ILogger log, string msg)
{
log.LogInformation("PostSlackMessageAsync: enter.");
var slackWebHook = await KeyVaultAccessor.GetInstance().GetSecretAsync("AzTwitterSarSlackHook");
HttpClient httpClient = new HttpClient();
httpClient.Timeout = TimeSpan.FromSeconds(30);
Uri mlFuncUri = new Uri(slackWebHook);
/* Setting the property link_names is required for the channel
* alert to work. Alternatively (not tried), see
* https://discuss.newrelic.com/t/sending-alerts-to-slack-with-channel-notification/35921/3 */
var payload = JsonConvert.SerializeObject(new { text = $"{msg}", link_names = "1" });
var httpContent = new StringContent(payload, Encoding.UTF8, "application/json");
HttpResponseMessage httpResponseMsg = await httpClient.PostAsync(mlFuncUri, httpContent);
if (httpResponseMsg.StatusCode == HttpStatusCode.OK &&
httpResponseMsg.Content != null)
{
var result = await httpResponseMsg.Content.ReadAsStringAsync();
log.LogInformation("PostSlackMessageAsync: response: " + result);
}
else
{
log.LogInformation($"PostSlackMessageAsync: posting to slack failed, response code: {httpResponseMsg.StatusCode}.");
}
log.LogInformation("PostSlackMessageAsync: exit.");
return(0);
}
public static async Task <MlResult> GetMlScore([ActivityTrigger] string tweet, ILogger log)
{
log.LogInformation("A_GetMlScore: Start.");
string mlUriString = await KeyVaultAccessor.GetInstance().GetSecretAsync("AzTwitterSarAiUri");
MlResult result = new MlResult
{
Score = 0,
Label = PublishLabel.NotAssigned,
MlVersion = ""
};
if (mlUriString is null)
{
log.LogError($"ML-inference link not configured.");
}
else
{
var payload = JsonConvert.SerializeObject(new { tweet = tweet });
var httpContent = new StringContent(payload, Encoding.UTF8, "application/json");
HttpClient httpClient = new HttpClient();
httpClient.Timeout = TimeSpan.FromSeconds(30);
Uri mlFuncUri = new Uri(mlUriString);
log.LogInformation($"Calling ML-inference.");
HttpResponseMessage httpResponseMsg = null;
try
{
httpResponseMsg = await httpClient.PostAsync(mlFuncUri, httpContent);
}
catch (Exception e)
{
log.LogError($"Getting ML score failed: {e.Message}");
}
if (httpResponseMsg != null &&
httpResponseMsg.StatusCode == HttpStatusCode.OK &&
httpResponseMsg.Content != null)
{
var responseContent = await httpResponseMsg.Content.ReadAsStringAsync();
ResponseData ml_result = JsonConvert.DeserializeObject <ResponseData>(responseContent);
result.Score = ml_result.Score;
result.Label = ml_result.Label == 1 ? PublishLabel.Positive : PublishLabel.Negative;
result.MlVersion = ml_result.Version;
}
}
log.LogInformation("A_GetMlScore: Done.");
return(result);
}
public static KeyVaultAccessor GetInstance()
{
// C# thread-safe singleton pattern from refactoring.guru
// This conditional is needed to prevent threads stumbling over the
// lock once the instance is ready.
if (_instance == null)
{
lock (_lock)
{
// The first thread to acquire the lock, reaches this
// conditional, goes inside and creates the Singleton
// instance. Once it leaves the lock block, a thread that
// might have been waiting for the lock release may then
// enter this section. But since the Singleton field is
// already initialized, the thread won't create a new
// object.
if (_instance == null)
{
_instance = new KeyVaultAccessor();
}
}
}
return(_instance);
}
public static async Task <List <TweetProcessingData> > GetTweets([ActivityTrigger] string lastTweetId, ILogger log)
{
log.LogInformation($"A_GetTweets: Getting new tweets after {lastTweetId}.");
KeyVaultAccessor kva = KeyVaultAccessor.GetInstance();
string apiKey = await kva.GetSecretAsync("TwitterApiKey"); // aka consumer key
string apiSecretKey = await kva.GetSecretAsync("TwitterApiSecretKey"); // aka consumer secret
string accessToken = await kva.GetSecretAsync("TwitterAccessToken");
string accessTokenSecret = await kva.GetSecretAsync("TwitterAccessTokenSecret");
string monitoredTwitterAccount = Environment.GetEnvironmentVariable("MonitoredTwitterAccount");
List <TweetProcessingData> tpds = new List <TweetProcessingData>(); // return value, empty list if Twitter connection failure
var userCredentials = Auth.SetUserCredentials(apiKey, apiSecretKey, accessToken, accessTokenSecret);
try
{
// This variable is not used later, but seems to leave an id for the library.
var authenticatedUser = User.GetAuthenticatedUser(userCredentials);
}
catch (AggregateException ae)
{
// Inserted try-catch after a seemingly intermittent exception that lead to
// the service stopping completely, 20210102, ca. 11 am.
log.LogWarning($"A_GetTweets: User authentication failure: {ae.Message}. Return no tweets and retry in next cycle.");
return(tpds);
}
// Note: The following does NOT get MaximumNumberOfResults tweets
// from after lastTweetId!!! Rather it gets the most recent
// tweets with the early limit defined by lastTweetId OR the
// defined maximum, whichever is more limiting!
// (Therefore, in order to test on past tweets, one may need
// to increase MaximumNumberOfResults considerably to get ALL
// tweets from the one targeted to the current one.
SearchTweetsParameters searchParameter = new SearchTweetsParameters($"from:{monitoredTwitterAccount}")
{
MaximumNumberOfResults = 15,
SinceId = long.Parse(lastTweetId)
};
IEnumerable <ITweet> tweets = null;
try
{
tweets = await SearchAsync.SearchTweets(searchParameter);
}
catch (Exception e)
{
// Inserted try-catch after a seemingly intermittent exception that lead to
// the service stopping completely, 20201213, ca. 7 am.
log.LogWarning($"A_GetTweets: SearchTweets failed with exception: {e.Message}");
}
if (tweets is null)
{
log.LogWarning($"A_GetTweets: Twitter connection failure. Return no tweets and retry in next cycle.");
return(tpds);
}
// Since the further processing can scramble the order again, we don't need to sort here.
foreach (var tweet in tweets)
{
// Copy the data that we need over to a serializable struct.
TweetProcessingData tpd = new TweetProcessingData();
tpd.IdStr = tweet.IdStr;
tpd.CreatedAt = tweet.CreatedAt;
tpd.FullText = tweet.FullText;
tpd.Hashtags = String.Join("|", tweet.Hashtags.Select(t => t.Text));
tpd.InReplyToStatusIdStr = tweet.InReplyToStatusIdStr;
tpd.Url = tweet.Url;
tpd.TextWithoutTags = TweetAnalysis.removeHashtagsFromText(tweet.FullText, tweet.Hashtags);
tpds.Add(tpd);
}
log.LogInformation($"A_GetTweets: Done, got {tweets.Count()} new tweets.");
return(tpds);
}
