krafka 0.9.1

A pure Rust, async-native Apache Kafka client
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287

use bytes::{Buf, BufMut};

use super::{VersionedDecode, VersionedEncode, non_nullable_string};
use crate::error::{ErrorCode, Result};
use crate::protocol::api::ApiKey;
use crate::protocol::primitives::{Decode, Encode, KafkaString, TaggedFields, TryEncode};
use crate::protocol::{check_compact_array_len, encode_compact_array_len};

// ============================================================================
// ListTransactions API (Key 66)
//
// v0 baseline. All versions use flexible encoding.
// v1 adds DurationFilter (KIP-994).
// ============================================================================

/// ListTransactions request.
#[derive(Debug, Clone)]
pub struct ListTransactionsRequest {
    /// Filter by transaction states (empty = all).
    pub state_filters: Vec<String>,
    /// Filter by producer IDs (empty = all).
    pub producer_id_filters: Vec<i64>,
    /// Filter by minimum duration in millis (v1+). `-1` for no filter.
    pub duration_filter: i64,
}

impl ListTransactionsRequest {
    /// Get the API key.
    pub fn api_key() -> ApiKey {
        ApiKey::ListTransactions
    }

    /// Create a request that lists all transactions.
    pub fn all() -> Self {
        Self {
            state_filters: Vec::new(),
            producer_id_filters: Vec::new(),
            duration_filter: -1,
        }
    }

    /// Encode for version 0 (flexible encoding).
    pub fn encode_v0(&self, buf: &mut impl BufMut) -> Result<()> {
        encode_compact_array_len(self.state_filters.len(), buf)?;
        for s in &self.state_filters {
            KafkaString::new(s).try_encode_compact(buf)?;
        }
        encode_compact_array_len(self.producer_id_filters.len(), buf)?;
        for &pid in &self.producer_id_filters {
            pid.encode(buf);
        }
        TaggedFields::default().try_encode(buf)?;
        Ok(())
    }

    /// Encode for version 1 (adds duration filter).
    pub fn encode_v1(&self, buf: &mut impl BufMut) -> Result<()> {
        encode_compact_array_len(self.state_filters.len(), buf)?;
        for s in &self.state_filters {
            KafkaString::new(s).try_encode_compact(buf)?;
        }
        encode_compact_array_len(self.producer_id_filters.len(), buf)?;
        for &pid in &self.producer_id_filters {
            pid.encode(buf);
        }
        self.duration_filter.encode(buf);
        TaggedFields::default().try_encode(buf)?;
        Ok(())
    }
}

impl VersionedEncode for ListTransactionsRequest {
    fn encode_versioned(&self, version: i16, buf: &mut impl BufMut) -> Result<()> {
        match version {
            0 => self.encode_v0(buf),
            1 => self.encode_v1(buf),
            _ => unsupported_encode!("ListTransactionsRequest", version),
        }
    }
}

// ── Response ─────────────────────────────────────────────────────────────

/// A transaction state entry from ListTransactions.
#[derive(Debug, Clone)]
pub struct ListTransactionsStateEntry {
    /// Transactional ID.
    pub transactional_id: String,
    /// Producer ID.
    pub producer_id: i64,
    /// Current transaction state.
    pub transaction_state: String,
}

/// ListTransactions response.
#[derive(Debug, Clone)]
pub struct ListTransactionsResponse {
    /// Throttle time in milliseconds.
    pub throttle_time_ms: i32,
    /// Top-level error code.
    pub error_code: ErrorCode,
    /// State filters that were not recognized by the coordinator.
    pub unknown_state_filters: Vec<String>,
    /// Transaction states.
    pub transaction_states: Vec<ListTransactionsStateEntry>,
}

impl ListTransactionsResponse {
    /// Decode from version 0–1 (both have the same response wire format).
    pub fn decode_v0(buf: &mut impl Buf) -> Result<Self> {
        let throttle_time_ms = i32::decode(buf)?;
        let error_code = ErrorCode::from_i16(i16::decode(buf)?);

        let unknown_count =
            check_compact_array_len(crate::util::varint::decode_unsigned_varint(buf)?)?;
        let mut unknown_state_filters = Vec::with_capacity(unknown_count);
        for _ in 0..unknown_count {
            unknown_state_filters.push(non_nullable_string(
                "unknown_state_filter",
                KafkaString::decode_compact(buf)?.0,
            )?);
        }

        let state_count =
            check_compact_array_len(crate::util::varint::decode_unsigned_varint(buf)?)?;
        let mut transaction_states = Vec::with_capacity(state_count);
        for _ in 0..state_count {
            let transactional_id =
                non_nullable_string("transactional_id", KafkaString::decode_compact(buf)?.0)?;
            let producer_id = i64::decode(buf)?;
            let transaction_state =
                non_nullable_string("transaction_state", KafkaString::decode_compact(buf)?.0)?;
            let _ = TaggedFields::decode(buf)?;
            transaction_states.push(ListTransactionsStateEntry {
                transactional_id,
                producer_id,
                transaction_state,
            });
        }
        let _ = TaggedFields::decode(buf)?;

        Ok(Self {
            throttle_time_ms,
            error_code,
            unknown_state_filters,
            transaction_states,
        })
    }
}

impl VersionedDecode for ListTransactionsResponse {
    fn decode_versioned(version: i16, buf: &mut impl Buf) -> Result<Self> {
        match version {
            0..=1 => Self::decode_v0(buf),
            _ => unsupported_decode!("ListTransactionsResponse", version),
        }
    }
}

#[cfg(test)]
#[allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
mod tests {
    use super::*;

    use bytes::BytesMut;

    fn put_compact_string(buf: &mut BytesMut, s: &str) {
        crate::util::varint::encode_unsigned_varint((s.len() + 1) as u32, buf);
        buf.put_slice(s.as_bytes());
    }

    fn put_empty_tagged_fields(buf: &mut BytesMut) {
        crate::util::varint::encode_unsigned_varint(0, buf);
    }

    fn put_compact_array_len(buf: &mut BytesMut, count: usize) {
        crate::util::varint::encode_unsigned_varint((count + 1) as u32, buf);
    }

    #[test]
    fn test_list_transactions_api_key() {
        assert_eq!(ListTransactionsRequest::api_key(), ApiKey::ListTransactions);
    }

    #[test]
    fn test_list_transactions_request_all() {
        let request = ListTransactionsRequest::all();
        assert!(request.state_filters.is_empty());
        assert!(request.producer_id_filters.is_empty());
        assert_eq!(request.duration_filter, -1);
    }

    #[test]
    fn test_list_transactions_request_encode_v0() {
        let request = ListTransactionsRequest {
            state_filters: vec!["Ongoing".to_string()],
            producer_id_filters: vec![1000],
            duration_filter: -1,
        };
        let mut buf = BytesMut::new();
        request.encode_v0(&mut buf).unwrap();
        assert!(!buf.is_empty());
    }

    #[test]
    fn test_list_transactions_request_encode_v1() {
        let request = ListTransactionsRequest {
            state_filters: Vec::new(),
            producer_id_filters: Vec::new(),
            duration_filter: 60_000,
        };
        let mut buf = BytesMut::new();
        request.encode_v1(&mut buf).unwrap();
        assert!(!buf.is_empty());
    }

    #[test]
    fn test_list_transactions_versioned_unsupported() {
        let request = ListTransactionsRequest::all();
        let mut buf = BytesMut::new();
        assert!(request.encode_versioned(2, &mut buf).is_err());
    }

    #[test]
    fn test_list_transactions_response_decode_v0() {
        let mut buf = BytesMut::new();
        buf.put_i32(0); // throttle_time_ms
        buf.put_i16(0); // error_code
        put_compact_array_len(&mut buf, 0); // unknown_state_filters
        put_compact_array_len(&mut buf, 2); // transaction_states
        // txn 1
        put_compact_string(&mut buf, "txn-1");
        buf.put_i64(1000); // producer_id
        put_compact_string(&mut buf, "Ongoing");
        put_empty_tagged_fields(&mut buf);
        // txn 2
        put_compact_string(&mut buf, "txn-2");
        buf.put_i64(2000); // producer_id
        put_compact_string(&mut buf, "PrepareCommit");
        put_empty_tagged_fields(&mut buf);
        put_empty_tagged_fields(&mut buf); // top-level

        let resp = ListTransactionsResponse::decode_v0(&mut buf.freeze()).unwrap();
        assert!(resp.error_code.is_ok());
        assert!(resp.unknown_state_filters.is_empty());
        assert_eq!(resp.transaction_states.len(), 2);
        assert_eq!(resp.transaction_states[0].transactional_id, "txn-1");
        assert_eq!(resp.transaction_states[0].producer_id, 1000);
        assert_eq!(resp.transaction_states[0].transaction_state, "Ongoing");
        assert_eq!(resp.transaction_states[1].transactional_id, "txn-2");
        assert_eq!(
            resp.transaction_states[1].transaction_state,
            "PrepareCommit"
        );
    }

    #[test]
    fn test_list_transactions_response_with_unknown_filters() {
        let mut buf = BytesMut::new();
        buf.put_i32(0); // throttle_time_ms
        buf.put_i16(0); // error_code
        put_compact_array_len(&mut buf, 1); // unknown_state_filters
        put_compact_string(&mut buf, "BadState");
        put_compact_array_len(&mut buf, 0); // empty transaction_states
        put_empty_tagged_fields(&mut buf);

        let resp = ListTransactionsResponse::decode_v0(&mut buf.freeze()).unwrap();
        assert_eq!(resp.unknown_state_filters, vec!["BadState"]);
        assert!(resp.transaction_states.is_empty());
    }

    #[test]
    fn test_list_transactions_versioned_decode_unsupported() {
        let buf = BytesMut::new();
        assert!(ListTransactionsResponse::decode_versioned(2, &mut buf.freeze()).is_err());
    }

    #[test]
    fn test_list_transactions_versioned_encode_dispatches() {
        let request = ListTransactionsRequest::all();
        for v in 0..=1 {
            let mut buf = BytesMut::new();
            request.encode_versioned(v, &mut buf).unwrap();
            assert!(!buf.is_empty(), "v{v} should produce non-empty output");
        }
    }
}