pub trait ClientContext:
Send
+ Sync
+ 'static {
// Provided methods
fn enable_refresh_oauth_token(&self) -> bool { ... }
fn log(&self, level: RDKafkaLogLevel, fac: &str, log_message: &str) { ... }
fn stats(&self, statistics: Statistics) { ... }
fn stats_raw(&self, statistics: &[u8]) { ... }
fn error(&self, error: KafkaError, reason: &str) { ... }
fn rewrite_broker_addr(&self, addr: BrokerAddr) -> BrokerAddr { ... }
fn generate_oauth_token(
&self,
_oauthbearer_config: Option<&str>,
) -> Result<OAuthToken, Box<dyn Error>> { ... }
}
Expand description
Client-level context.
Each client (consumers and producers included) has a context object that can
be used to customize its behavior. Implementing ClientContext
enables the
customization of methods common to all clients, while ProducerContext
and ConsumerContext
are specific to producers and consumers. Refer to
the list of methods to see which callbacks can currently be overridden.
Important: implementations of ClientContext
must be thread safe, as
they might be shared between multiple threads.
Provided Methods§
Sourcefn enable_refresh_oauth_token(&self) -> bool
fn enable_refresh_oauth_token(&self) -> bool
Whether to periodically refresh the SASL OAUTHBEARER
token
by calling ClientContext::generate_oauth_token
.
If disabled, librdkafka’s default token refresh callback is used instead.
This parameter is only relevant when using the OAUTHBEARER
SASL
mechanism.
Sourcefn log(&self, level: RDKafkaLogLevel, fac: &str, log_message: &str)
fn log(&self, level: RDKafkaLogLevel, fac: &str, log_message: &str)
Receives log lines from librdkafka.
The default implementation forwards the log lines to the appropriate
log
crate macro. Consult the RDKafkaLogLevel
documentation for
details about the log level mapping.
Sourcefn stats(&self, statistics: Statistics)
fn stats(&self, statistics: Statistics)
Receives the decoded statistics of the librdkafka client. To enable, the
statistics.interval.ms
configuration parameter must be specified.
The default implementation logs the statistics at the info
log level.
Sourcefn stats_raw(&self, statistics: &[u8])
fn stats_raw(&self, statistics: &[u8])
Receives the JSON-encoded statistics of the librdkafka client. To
enable, the statistics.interval.ms
configuration parameter must be
specified.
The default implementation calls ClientContext::stats
with the
decoded statistics, logging an error if the decoding fails.
Sourcefn error(&self, error: KafkaError, reason: &str)
fn error(&self, error: KafkaError, reason: &str)
Receives global errors from the librdkafka client.
The default implementation logs the error at the error
log level.
Sourcefn rewrite_broker_addr(&self, addr: BrokerAddr) -> BrokerAddr
fn rewrite_broker_addr(&self, addr: BrokerAddr) -> BrokerAddr
Rewrites a broker address for DNS resolution.
This method is invoked before performing DNS resolution on a broker address. The returned address is used in place of the original address. It is useful to allow connecting to a Kafka cluster over a tunnel (e.g., SSH or AWS PrivateLink), where the broker addresses returned by the bootstrap server need to be rewritten to be routed through the tunnel.
The default implementation returns the address unchanged.
Sourcefn generate_oauth_token(
&self,
_oauthbearer_config: Option<&str>,
) -> Result<OAuthToken, Box<dyn Error>>
fn generate_oauth_token( &self, _oauthbearer_config: Option<&str>, ) -> Result<OAuthToken, Box<dyn Error>>
Generates an OAuth token from the provided configuration.
Override with an appropriate implementation when using the OAUTHBEARER
SASL authentication mechanism. For this method to be called, you must
also set ClientContext::enable_refresh_oauth_token
to true.
The fmt::Display
implementation of the returned error must not
generate a message with an embedded null character.
The default implementation always returns an error and is meant to be overridden.