/// <summary>
/// Initializes a new instance of the <see cref="EventHubConnection"/> class.
/// </summary>
///
/// <param name="connectionString">The connection string to use for connecting to the Event Hubs namespace; it is expected that the shared key properties are contained in this connection string, but not the Event Hub name.</param>
/// <param name="eventHubName">The name of the specific Event Hub to associate the connection with.</param>
/// <param name="connectionOptions">A set of options to apply when configuring the connection.</param>
///
/// <remarks>
/// If the connection string is copied from the Event Hub itself, it will contain the name of the desired Event Hub,
/// and can be used directly without passing the <paramref name="eventHubName" />. The name of the Event Hub should be
/// passed only once, either as part of the connection string or separately.
/// </remarks>
///
public EventHubConnection(string connectionString,
string eventHubName,
EventHubConnectionOptions connectionOptions)
{
Argument.AssertNotNullOrEmpty(connectionString, nameof(connectionString));
connectionOptions = connectionOptions?.Clone() ?? new EventHubConnectionOptions();
ValidateConnectionOptions(connectionOptions);
var connectionStringProperties = EventHubsConnectionStringProperties.Parse(connectionString);
connectionStringProperties.Validate(eventHubName, nameof(connectionString));
var fullyQualifiedNamespace = connectionStringProperties.FullyQualifiedNamespace;
if (string.IsNullOrEmpty(eventHubName))
{
eventHubName = connectionStringProperties.EventHubName;
}
SharedAccessSignature sharedAccessSignature;
if (string.IsNullOrEmpty(connectionStringProperties.SharedAccessSignature))
{
sharedAccessSignature = new SharedAccessSignature(
BuildConnectionAudience(connectionOptions.TransportType, fullyQualifiedNamespace, eventHubName),
connectionStringProperties.SharedAccessKeyName,
connectionStringProperties.SharedAccessKey);
}
else
{
sharedAccessSignature = new SharedAccessSignature(connectionStringProperties.SharedAccessSignature);
}
var sharedCredentials = new SharedAccessSignatureCredential(sharedAccessSignature);
var tokenCredentials = new EventHubTokenCredential(sharedCredentials, BuildConnectionAudience(connectionOptions.TransportType, fullyQualifiedNamespace, eventHubName));
FullyQualifiedNamespace = fullyQualifiedNamespace;
EventHubName = eventHubName;
Options = connectionOptions;
#pragma warning disable CA2214 // Do not call overridable methods in constructors. This internal method is virtual for testing purposes.
InnerClient = CreateTransportClient(fullyQualifiedNamespace, eventHubName, tokenCredentials, connectionOptions);
#pragma warning restore CA2214 // Do not call overridable methods in constructors.
}
/// <summary>
/// Parses the specified Event Hubs connection string into its component properties.
/// </summary>
///
/// <param name="connectionString">The connection string to parse.</param>
///
/// <returns>The component properties parsed from the connection string.</returns>
///
/// <exception cref="FormatException">The specified connection string was malformed and could not be parsed.</exception>
///
public static EventHubsConnectionStringProperties Parse(string connectionString)
{
Argument.AssertNotNullOrEmpty(connectionString, nameof(connectionString));
var parsedValues = new EventHubsConnectionStringProperties();
var tokenPositionModifier = (connectionString[0] == TokenValuePairDelimiter) ? 0 : 1;
var lastPosition = 0;
var currentPosition = 0;
int valueStart;
string slice;
string token;
string value;
while (currentPosition != -1)
{
// Slice the string into the next token/value pair.
currentPosition = connectionString.IndexOf(TokenValuePairDelimiter, lastPosition + 1);
if (currentPosition >= 0)
{
slice = connectionString.Substring(lastPosition, (currentPosition - lastPosition));
}
else
{
slice = connectionString.Substring(lastPosition);
}
// Break the token and value apart, if this is a legal pair.
valueStart = slice.IndexOf(TokenValueSeparator);
if (valueStart >= 0)
{
token = slice.Substring((1 - tokenPositionModifier), (valueStart - 1 + tokenPositionModifier));
value = slice.Substring(valueStart + 1);
// Guard against leading and trailing spaces, only trimming if there is a need.
if ((!string.IsNullOrEmpty(token)) && (char.IsWhiteSpace(token[0])) || char.IsWhiteSpace(token[token.Length - 1]))
{
token = token.Trim();
}
if ((!string.IsNullOrEmpty(value)) && (char.IsWhiteSpace(value[0]) || char.IsWhiteSpace(value[value.Length - 1])))
{
value = value.Trim();
}
// If there was no value for a key, then consider the connection string to
// be malformed.
if (string.IsNullOrEmpty(value))
{
throw new FormatException(Resources.InvalidConnectionString);
}
// Compare the token against the known connection string properties and capture the
// pair if they are a known attribute.
if (string.Compare(EndpointToken, token, StringComparison.OrdinalIgnoreCase) == 0)
{
var endpointBuilder = new UriBuilder(value)
{
Scheme = EventHubsEndpointScheme,
Port = -1
};
if ((string.Compare(endpointBuilder.Scheme, EventHubsEndpointSchemeName, StringComparison.OrdinalIgnoreCase) != 0) ||
(Uri.CheckHostName(endpointBuilder.Host) == UriHostNameType.Unknown))
{
throw new FormatException(Resources.InvalidConnectionString);
}
parsedValues.Endpoint = endpointBuilder.Uri;
}
else if (string.Compare(EventHubNameToken, token, StringComparison.OrdinalIgnoreCase) == 0)
{
parsedValues.EventHubName = value;
}
else if (string.Compare(SharedAccessKeyNameToken, token, StringComparison.OrdinalIgnoreCase) == 0)
{
parsedValues.SharedAccessKeyName = value;
}
else if (string.Compare(SharedAccessKeyValueToken, token, StringComparison.OrdinalIgnoreCase) == 0)
{
parsedValues.SharedAccessKey = value;
}
else if (string.Compare(SharedAccessSignatureToken, token, StringComparison.OrdinalIgnoreCase) == 0)
{
parsedValues.SharedAccessSignature = value;
}
}
else if ((slice.Length != 1) || (slice[0] != TokenValuePairDelimiter))
{
// This wasn't a legal pair and it is not simply a trailing delimiter; consider
// the connection string to be malformed.
throw new FormatException(Resources.InvalidConnectionString);
}
tokenPositionModifier = 0;
lastPosition = currentPosition;
}
return(parsedValues);
}