Enum KafkaError 

#[non_exhaustive]
pub enum KafkaError {
    Connect(Box<dyn StdError + Send + Sync>),
    Publish(Box<dyn StdError + Send + Sync>),
    Subscribe(Box<dyn StdError + Send + Sync>),
    Consume(Box<dyn StdError + Send + Sync>),
    Closed {
        topic: String,
    },
    InvalidOptions(String),
    TransactionBusy {
        id: String,
    },
    NoTransaction {
        id: String,
    },
    SchemaRegistry(Box<dyn StdError + Send + Sync>),
    SchemaRegistryTimeout {
        request: String,
        timeout: Duration,
    },
    WireFormat(Box<dyn StdError + Send + Sync>),
}

Errors returned by KafkaBroker and the types it hands out.

Underlying rdkafka errors are boxed as sources so the client library does not leak into this crate’s public API surface.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Connect(Box<dyn StdError + Send + Sync>)

Creating a client failed or the cluster was unreachable during the connect probe.

Publish(Box<dyn StdError + Send + Sync>)

Publishing a message failed or the broker did not confirm its delivery.

Subscribe(Box<dyn StdError + Send + Sync>)

Creating a consumer or subscribing it to its topic failed.

Consume(Box<dyn StdError + Send + Sync>)

Receiving a delivery from an open consumer failed.

Closed

A handle aliasing the connection was used after the broker shut down.

The lifecycle ladder makes misuse through the owner’s handle a compile error: ConnectedBroker::shutdown consumes the connected broker. Publishers paired off it earlier, and subscriptions still open, keep aliasing the closed connection, so their operations report this instead of silently succeeding against a dead connection.

Fields

topic: String

The topic the operation targeted, or the transactional id of a transaction control call.

InvalidOptions(String)

The requested combination of options cannot be executed.

The message names the offending option and the remediation.

TransactionBusy

begin_transaction found a transaction already open on this publisher.

One producer runs one transaction at a time, so a second begin means two flows share one publisher; erroring beats silently merging their messages into one transaction. Concurrent transactional flows need distinct publishers - one per partition via TransactionalPartitions, or distinct explicit ids.

Fields

id: String

The transactional id of the publisher that already has an open transaction.

NoTransaction

commit or abort was called with no transaction open on this publisher.

Fields

id: String

The transactional id of the publisher the call was made on.

SchemaRegistry(Box<dyn StdError + Send + Sync>)

A Schema Registry request failed: unreachable registry, rejected credentials, an unknown schema id or subject, or a schema the registry refused.

SchemaRegistryTimeout

A Schema Registry request did not answer within the client’s request timeout.

A registry that accepts the connection and then goes silent is the case this separates from an outright failure: both edges resolve schemas on the async delivery path, so without a deadline one silent registry holds a delivery for as long as it stays silent. SchemaRegistry::request_timeout sets the deadline.

Fields

request: String

The registry path the request targeted, for example /schemas/ids/7.

timeout: Duration

The deadline that expired.

WireFormat(Box<dyn StdError + Send + Sync>)

A value could not be written to, or read from, its binary wire form.

This is the byte lanes’ own failure: the Avro or Protobuf encoder rejected the value, the payload is not the datum a schema describes, or a delivery does not carry the Confluent envelope the reader expected. It stays distinct from SchemaRegistry, which is the registry conversation failing - the fixed-schema lane reaches no registry at all, so folding the two would make every diagnostic point at a component that was never involved.

Trait Implementations

impl Debug for KafkaError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for KafkaError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for KafkaError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.