Use num_enum to auto-generate reverse mappings for rd_kafka_resp_err_t

Signed-off-by: Ivan Gozali <[email protected]>

Author: igozali

examples/asynchronous_processing.rs

@@ -1,9 +1,9 @@
 use std::thread;
 use std::time::Duration;
 
-use clap::{App, Arg, value_t};
-use futures::{StreamExt, TryStreamExt};
+use clap::{value_t, App, Arg};
 use futures::stream::FuturesUnordered;
+use futures::{StreamExt, TryStreamExt};
 use log::info;
 
 use rdkafka::config::ClientConfig;

rdkafka-sys/Cargo.toml

@@ -12,6 +12,7 @@ categories = ["external-ffi-bindings"]
 edition = "2018"
 
 [dependencies]
+num_enum = "0.4.2"
 libc = "0.2.65"
 openssl-sys = { version = "0.9.48", optional = true }
 libz-sys = { version = "1.0", optional = true }

rdkafka-sys/src/bindings.rs

@@ -1,5 +1,6 @@
 /* automatically generated by rust-bindgen */
 
+use num_enum::TryFromPrimitive;
 type FILE = libc::FILE;
 type sockaddr = libc::sockaddr;
 
@@ -97,7 +98,7 @@ pub struct rd_kafka_topic_result_s {
 }
 pub type rd_kafka_topic_result_t = rd_kafka_topic_result_s;
 #[repr(i32)]
-#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, TryFromPrimitive)]
 pub enum rd_kafka_resp_err_t {
     RD_KAFKA_RESP_ERR__BEGIN = -200,
     RD_KAFKA_RESP_ERR__BAD_MSG = -199,

rdkafka-sys/src/helpers.rs

@@ -3,154 +3,6 @@ use crate::types::RDKafkaError::*;
 use crate::types::RDKafkaRespErr;
 use crate::types::RDKafkaRespErr::*;
 
-/// This is not great. For legacy reasons some usage of rd_kafka_resp_err_t is
-/// passed as an integer in some places. There seems to be no easy way in Rust to
-/// match this the other way around so we do it manually.
-pub fn primitive_to_rd_kafka_resp_err_t(error: i32) -> Option<RDKafkaRespErr> {
-    match error {
-        -200 => Some(RD_KAFKA_RESP_ERR__BEGIN),
-        -199 => Some(RD_KAFKA_RESP_ERR__BAD_MSG),
-        -198 => Some(RD_KAFKA_RESP_ERR__BAD_COMPRESSION),
-        -197 => Some(RD_KAFKA_RESP_ERR__DESTROY),
-        -196 => Some(RD_KAFKA_RESP_ERR__FAIL),
-        -195 => Some(RD_KAFKA_RESP_ERR__TRANSPORT),
-        -194 => Some(RD_KAFKA_RESP_ERR__CRIT_SYS_RESOURCE),
-        -193 => Some(RD_KAFKA_RESP_ERR__RESOLVE),
-        -192 => Some(RD_KAFKA_RESP_ERR__MSG_TIMED_OUT),
-        -191 => Some(RD_KAFKA_RESP_ERR__PARTITION_EOF),
-        -190 => Some(RD_KAFKA_RESP_ERR__UNKNOWN_PARTITION),
-        -189 => Some(RD_KAFKA_RESP_ERR__FS),
-        -188 => Some(RD_KAFKA_RESP_ERR__UNKNOWN_TOPIC),
-        -187 => Some(RD_KAFKA_RESP_ERR__ALL_BROKERS_DOWN),
-        -186 => Some(RD_KAFKA_RESP_ERR__INVALID_ARG),
-        -185 => Some(RD_KAFKA_RESP_ERR__TIMED_OUT),
-        -184 => Some(RD_KAFKA_RESP_ERR__QUEUE_FULL),
-        -183 => Some(RD_KAFKA_RESP_ERR__ISR_INSUFF),
-        -182 => Some(RD_KAFKA_RESP_ERR__NODE_UPDATE),
-        -181 => Some(RD_KAFKA_RESP_ERR__SSL),
-        -180 => Some(RD_KAFKA_RESP_ERR__WAIT_COORD),
-        -179 => Some(RD_KAFKA_RESP_ERR__UNKNOWN_GROUP),
-        -178 => Some(RD_KAFKA_RESP_ERR__IN_PROGRESS),
-        -177 => Some(RD_KAFKA_RESP_ERR__PREV_IN_PROGRESS),
-        -176 => Some(RD_KAFKA_RESP_ERR__EXISTING_SUBSCRIPTION),
-        -175 => Some(RD_KAFKA_RESP_ERR__ASSIGN_PARTITIONS),
-        -174 => Some(RD_KAFKA_RESP_ERR__REVOKE_PARTITIONS),
-        -173 => Some(RD_KAFKA_RESP_ERR__CONFLICT),
-        -172 => Some(RD_KAFKA_RESP_ERR__STATE),
-        -171 => Some(RD_KAFKA_RESP_ERR__UNKNOWN_PROTOCOL),
-        -170 => Some(RD_KAFKA_RESP_ERR__NOT_IMPLEMENTED),
-        -169 => Some(RD_KAFKA_RESP_ERR__AUTHENTICATION),
-        -168 => Some(RD_KAFKA_RESP_ERR__NO_OFFSET),
-        -167 => Some(RD_KAFKA_RESP_ERR__OUTDATED),
-        -166 => Some(RD_KAFKA_RESP_ERR__TIMED_OUT_QUEUE),
-        -165 => Some(RD_KAFKA_RESP_ERR__UNSUPPORTED_FEATURE),
-        -164 => Some(RD_KAFKA_RESP_ERR__WAIT_CACHE),
-        -163 => Some(RD_KAFKA_RESP_ERR__INTR),
-        -162 => Some(RD_KAFKA_RESP_ERR__KEY_SERIALIZATION),
-        -161 => Some(RD_KAFKA_RESP_ERR__VALUE_SERIALIZATION),
-        -160 => Some(RD_KAFKA_RESP_ERR__KEY_DESERIALIZATION),
-        -159 => Some(RD_KAFKA_RESP_ERR__VALUE_DESERIALIZATION),
-        -158 => Some(RD_KAFKA_RESP_ERR__PARTIAL),
-        -157 => Some(RD_KAFKA_RESP_ERR__READ_ONLY),
-        -156 => Some(RD_KAFKA_RESP_ERR__NOENT),
-        -155 => Some(RD_KAFKA_RESP_ERR__UNDERFLOW),
-        -154 => Some(RD_KAFKA_RESP_ERR__INVALID_TYPE),
-        -153 => Some(RD_KAFKA_RESP_ERR__RETRY),
-        -152 => Some(RD_KAFKA_RESP_ERR__PURGE_QUEUE),
-        -151 => Some(RD_KAFKA_RESP_ERR__PURGE_INFLIGHT),
-        -150 => Some(RD_KAFKA_RESP_ERR__FATAL),
-        -149 => Some(RD_KAFKA_RESP_ERR__INCONSISTENT),
-        -148 => Some(RD_KAFKA_RESP_ERR__GAPLESS_GUARANTEE),
-        -147 => Some(RD_KAFKA_RESP_ERR__MAX_POLL_EXCEEDED),
-        -100 => Some(RD_KAFKA_RESP_ERR__END),
-        -1 => Some(RD_KAFKA_RESP_ERR_UNKNOWN),
-        0 => Some(RD_KAFKA_RESP_ERR_NO_ERROR),
-        1 => Some(RD_KAFKA_RESP_ERR_OFFSET_OUT_OF_RANGE),
-        2 => Some(RD_KAFKA_RESP_ERR_INVALID_MSG),
-        3 => Some(RD_KAFKA_RESP_ERR_UNKNOWN_TOPIC_OR_PART),
-        4 => Some(RD_KAFKA_RESP_ERR_INVALID_MSG_SIZE),
-        5 => Some(RD_KAFKA_RESP_ERR_LEADER_NOT_AVAILABLE),
-        6 => Some(RD_KAFKA_RESP_ERR_NOT_LEADER_FOR_PARTITION),
-        7 => Some(RD_KAFKA_RESP_ERR_REQUEST_TIMED_OUT),
-        8 => Some(RD_KAFKA_RESP_ERR_BROKER_NOT_AVAILABLE),
-        9 => Some(RD_KAFKA_RESP_ERR_REPLICA_NOT_AVAILABLE),
-        10 => Some(RD_KAFKA_RESP_ERR_MSG_SIZE_TOO_LARGE),
-        11 => Some(RD_KAFKA_RESP_ERR_STALE_CTRL_EPOCH),
-        12 => Some(RD_KAFKA_RESP_ERR_OFFSET_METADATA_TOO_LARGE),
-        13 => Some(RD_KAFKA_RESP_ERR_NETWORK_EXCEPTION),
-        14 => Some(RD_KAFKA_RESP_ERR_GROUP_LOAD_IN_PROGRESS),
-        15 => Some(RD_KAFKA_RESP_ERR_GROUP_COORDINATOR_NOT_AVAILABLE),
-        16 => Some(RD_KAFKA_RESP_ERR_NOT_COORDINATOR_FOR_GROUP),
-        17 => Some(RD_KAFKA_RESP_ERR_TOPIC_EXCEPTION),
-        18 => Some(RD_KAFKA_RESP_ERR_RECORD_LIST_TOO_LARGE),
-        19 => Some(RD_KAFKA_RESP_ERR_NOT_ENOUGH_REPLICAS),
-        20 => Some(RD_KAFKA_RESP_ERR_NOT_ENOUGH_REPLICAS_AFTER_APPEND),
-        21 => Some(RD_KAFKA_RESP_ERR_INVALID_REQUIRED_ACKS),
-        22 => Some(RD_KAFKA_RESP_ERR_ILLEGAL_GENERATION),
-        23 => Some(RD_KAFKA_RESP_ERR_INCONSISTENT_GROUP_PROTOCOL),
-        24 => Some(RD_KAFKA_RESP_ERR_INVALID_GROUP_ID),
-        25 => Some(RD_KAFKA_RESP_ERR_UNKNOWN_MEMBER_ID),
-        26 => Some(RD_KAFKA_RESP_ERR_INVALID_SESSION_TIMEOUT),
-        27 => Some(RD_KAFKA_RESP_ERR_REBALANCE_IN_PROGRESS),
-        28 => Some(RD_KAFKA_RESP_ERR_INVALID_COMMIT_OFFSET_SIZE),
-        29 => Some(RD_KAFKA_RESP_ERR_TOPIC_AUTHORIZATION_FAILED),
-        30 => Some(RD_KAFKA_RESP_ERR_GROUP_AUTHORIZATION_FAILED),
-        31 => Some(RD_KAFKA_RESP_ERR_CLUSTER_AUTHORIZATION_FAILED),
-        32 => Some(RD_KAFKA_RESP_ERR_INVALID_TIMESTAMP),
-        33 => Some(RD_KAFKA_RESP_ERR_UNSUPPORTED_SASL_MECHANISM),
-        34 => Some(RD_KAFKA_RESP_ERR_ILLEGAL_SASL_STATE),
-        35 => Some(RD_KAFKA_RESP_ERR_UNSUPPORTED_VERSION),
-        36 => Some(RD_KAFKA_RESP_ERR_TOPIC_ALREADY_EXISTS),
-        37 => Some(RD_KAFKA_RESP_ERR_INVALID_PARTITIONS),
-        38 => Some(RD_KAFKA_RESP_ERR_INVALID_REPLICATION_FACTOR),
-        39 => Some(RD_KAFKA_RESP_ERR_INVALID_REPLICA_ASSIGNMENT),
-        40 => Some(RD_KAFKA_RESP_ERR_INVALID_CONFIG),
-        41 => Some(RD_KAFKA_RESP_ERR_NOT_CONTROLLER),
-        42 => Some(RD_KAFKA_RESP_ERR_INVALID_REQUEST),
-        43 => Some(RD_KAFKA_RESP_ERR_UNSUPPORTED_FOR_MESSAGE_FORMAT),
-        44 => Some(RD_KAFKA_RESP_ERR_POLICY_VIOLATION),
-        45 => Some(RD_KAFKA_RESP_ERR_OUT_OF_ORDER_SEQUENCE_NUMBER),
-        46 => Some(RD_KAFKA_RESP_ERR_DUPLICATE_SEQUENCE_NUMBER),
-        47 => Some(RD_KAFKA_RESP_ERR_INVALID_PRODUCER_EPOCH),
-        48 => Some(RD_KAFKA_RESP_ERR_INVALID_TXN_STATE),
-        49 => Some(RD_KAFKA_RESP_ERR_INVALID_PRODUCER_ID_MAPPING),
-        50 => Some(RD_KAFKA_RESP_ERR_INVALID_TRANSACTION_TIMEOUT),
-        51 => Some(RD_KAFKA_RESP_ERR_CONCURRENT_TRANSACTIONS),
-        52 => Some(RD_KAFKA_RESP_ERR_TRANSACTION_COORDINATOR_FENCED),
-        53 => Some(RD_KAFKA_RESP_ERR_TRANSACTIONAL_ID_AUTHORIZATION_FAILED),
-        54 => Some(RD_KAFKA_RESP_ERR_SECURITY_DISABLED),
-        55 => Some(RD_KAFKA_RESP_ERR_OPERATION_NOT_ATTEMPTED),
-        56 => Some(RD_KAFKA_RESP_ERR_KAFKA_STORAGE_ERROR),
-        57 => Some(RD_KAFKA_RESP_ERR_LOG_DIR_NOT_FOUND),
-        58 => Some(RD_KAFKA_RESP_ERR_SASL_AUTHENTICATION_FAILED),
-        59 => Some(RD_KAFKA_RESP_ERR_UNKNOWN_PRODUCER_ID),
-        60 => Some(RD_KAFKA_RESP_ERR_REASSIGNMENT_IN_PROGRESS),
-        61 => Some(RD_KAFKA_RESP_ERR_DELEGATION_TOKEN_AUTH_DISABLED),
-        62 => Some(RD_KAFKA_RESP_ERR_DELEGATION_TOKEN_NOT_FOUND),
-        63 => Some(RD_KAFKA_RESP_ERR_DELEGATION_TOKEN_OWNER_MISMATCH),
-        64 => Some(RD_KAFKA_RESP_ERR_DELEGATION_TOKEN_REQUEST_NOT_ALLOWED),
-        65 => Some(RD_KAFKA_RESP_ERR_DELEGATION_TOKEN_AUTHORIZATION_FAILED),
-        66 => Some(RD_KAFKA_RESP_ERR_DELEGATION_TOKEN_EXPIRED),
-        67 => Some(RD_KAFKA_RESP_ERR_INVALID_PRINCIPAL_TYPE),
-        68 => Some(RD_KAFKA_RESP_ERR_NON_EMPTY_GROUP),
-        69 => Some(RD_KAFKA_RESP_ERR_GROUP_ID_NOT_FOUND),
-        70 => Some(RD_KAFKA_RESP_ERR_FETCH_SESSION_ID_NOT_FOUND),
-        71 => Some(RD_KAFKA_RESP_ERR_INVALID_FETCH_SESSION_EPOCH),
-        72 => Some(RD_KAFKA_RESP_ERR_LISTENER_NOT_FOUND),
-        73 => Some(RD_KAFKA_RESP_ERR_TOPIC_DELETION_DISABLED),
-        74 => Some(RD_KAFKA_RESP_ERR_FENCED_LEADER_EPOCH),
-        75 => Some(RD_KAFKA_RESP_ERR_UNKNOWN_LEADER_EPOCH),
-        76 => Some(RD_KAFKA_RESP_ERR_UNSUPPORTED_COMPRESSION_TYPE),
-        77 => Some(RD_KAFKA_RESP_ERR_STALE_BROKER_EPOCH),
-        78 => Some(RD_KAFKA_RESP_ERR_OFFSET_NOT_AVAILABLE),
-        79 => Some(RD_KAFKA_RESP_ERR_MEMBER_ID_REQUIRED),
-        80 => Some(RD_KAFKA_RESP_ERR_PREFERRED_LEADER_NOT_AVAILABLE),
-        81 => Some(RD_KAFKA_RESP_ERR_GROUP_MAX_SIZE_REACHED),
-        // END ALL
-        _ => None,
-    }
-}
-
 pub fn rd_kafka_resp_err_t_to_rdkafka_error(err: RDKafkaRespErr) -> RDKafkaError {
     match err {
         RD_KAFKA_RESP_ERR__BEGIN => Begin,
@@ -298,18 +150,3 @@ pub fn rd_kafka_resp_err_t_to_rdkafka_error(err: RDKafkaRespErr) -> RDKafkaError
         RD_KAFKA_RESP_ERR_END_ALL => EndAll,
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_conversion() {
-        for error_code in -299..300 {
-            if let Some(resp_err) = primitive_to_rd_kafka_resp_err_t(error_code) {
-                let kafka_error = rd_kafka_resp_err_t_to_rdkafka_error(resp_err);
-                assert_eq!(error_code, kafka_error as i32);
-            }
-        }
-    }
-}

rdkafka-sys/src/types.rs

@@ -1,4 +1,6 @@
 //! This module contains type aliases for types defined in the auto-generated bindings.
+
+use std::convert::TryFrom;
 use std::ffi::CStr;
 use std::{error, fmt};
 
@@ -395,14 +397,14 @@ impl From<RDKafkaRespErr> for RDKafkaError {
 
 impl fmt::Display for RDKafkaError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        let description = match helpers::primitive_to_rd_kafka_resp_err_t(*self as i32) {
-            Some(err) => {
+        let description = match RDKafkaRespErr::try_from(*self as i32) {
+            Ok(err) => {
                 let cstr = unsafe { bindings::rd_kafka_err2str(err) };
                 unsafe { CStr::from_ptr(cstr) }
                     .to_string_lossy()
                     .into_owned()
             }
-            None => "Unknown error".to_owned(),
+            Err(_) => "Unknown error".to_owned(),
         };
 
         write!(f, "{:?} ({})", self, description)

rdkafka-sys/update-bindings.sh

@@ -14,6 +14,10 @@ bindgen \
     --whitelist-var "rd_kafka.*|RD_KAFKA_.*" \
     --no-recursive-whitelist \
     --blacklist-function "rd_kafka_conf_set_open_cb" \
+    --raw-line "use num_enum::TryFromPrimitive;" \
     --raw-line "type FILE = libc::FILE;" \
     --raw-line "type sockaddr = libc::sockaddr;" \
     librdkafka/src/rdkafka.h -o src/bindings.rs
+
+# Derive TryFromPrimitive for rd_kafka_resp_err_t.
+perl -i -p0e 's/#\[derive\((.*)\)\]\npub enum rd_kafka_resp_err_t/#\[derive($1, TryFromPrimitive)\]\npub enum rd_kafka_resp_err_t/s' src/bindings.rs

src/client.rs

@@ -1,5 +1,6 @@
 //! Common client functionalities.
 
+use std::convert::TryFrom;
 use std::ffi::{CStr, CString};
 use std::mem;
 use std::os::raw::c_char;
@@ -420,8 +421,7 @@ pub(crate) unsafe extern "C" fn native_error_cb<C: ClientContext>(
     reason: *const c_char,
     opaque: *mut c_void,
 ) {
-    let err = rdsys::primitive_to_rd_kafka_resp_err_t(err)
-        .expect("global error not an rd_kafka_resp_err_t");
+    let err = RDKafkaRespErr::try_from(err).expect("global error not an rd_kafka_resp_err_t");
     let error = KafkaError::Global(err.into());
     let reason = CStr::from_ptr(reason).to_string_lossy();