private async Task PublishWithRetryAsync <T>(string source, string subject, T cloudEvent, WorkflowEventSubscription destination)
{
try
{
await Retriable.RetryAsync(() => this.PublishAsync(source, subject, cloudEvent, destination)).ConfigureAwait(false);
}
catch (Exception ex)
{
// In this "v1" solution to event publishing, we don't want exceptions to propagate outside the
// publisher because we don't want failure in event publishing to break anything.
this.logger.LogError(
ex,
"Unexpected exception when trying to a CloudEvent with source '{source}', '{subject}' and destinationUrl '{destinationUrl}' with authentication resource '{msiAuthenticationResource}'.",
source,
subject,
destination?.ExternalUrl,
destination?.MsiAuthenticationResource);
}
}
private async Task PublishAsync <T>(string source, string subject, T cloudEvent, WorkflowEventSubscription destination)
{
this.logger.LogDebug(
"Initialising event publish request for subject '{subject}' and source '{source}' to external URL '{externalUrl}'",
subject,
source,
destination.ExternalUrl);
var request = new HttpRequestMessage(HttpMethod.Post, destination.ExternalUrl);
if (destination.AuthenticateWithManagedServiceIdentity)
{
AccessTokenDetail tokenDetails = await this.serviceIdentityTokenSource.GetAccessTokenAsync(
new AccessTokenRequest(new[] { $"{destination.MsiAuthenticationResource}/.default" }))
.ConfigureAwait(false);
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", tokenDetails.AccessToken);
}
request.Content = new StringContent(
JsonConvert.SerializeObject(cloudEvent, this.serializerSettingsProvider.Instance),
Encoding.UTF8,
"application/cloudevents");
HttpResponseMessage httpResponse = await this.httpClient.SendAsync(request).ConfigureAwait(false);
if (!httpResponse.IsSuccessStatusCode)
{
throw new CloudEventPublisherException(
subject,
source,
destination.ExternalUrl,
httpResponse.StatusCode,
httpResponse.ReasonPhrase);
}
}
