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

use bytes::{Buf, BufMut};

use super::{VersionedDecode, VersionedEncode, non_nullable_string};
use crate::error::{ErrorCode, Result};
use crate::protocol::primitives::{Decode, Encode, KafkaString, TaggedFields, TryEncode};
use crate::protocol::{
    array_len_i32, check_compact_array_len, check_decode_array_len, encode_compact_array_len,
};

// ============================================================================
// DeleteGroups API (Key 42)
// ============================================================================

/// DeleteGroups request (API Key 42).
#[derive(Debug, Clone)]
pub struct DeleteGroupsRequest {
    /// Group names to delete.
    pub group_names: Vec<String>,
}

impl DeleteGroupsRequest {
    /// Create a new request.
    pub fn new(group_names: Vec<String>) -> Self {
        Self { group_names }
    }

    /// Encode for version 0–1 (non-flexible).
    pub fn encode_v0(&self, buf: &mut impl BufMut) -> Result<()> {
        array_len_i32(self.group_names.len())?.encode(buf);
        for name in &self.group_names {
            KafkaString::new(name).try_encode(buf)?;
        }
        Ok(())
    }

    /// Encode for version 2 (flexible encoding).
    pub fn encode_v2(&self, buf: &mut impl BufMut) -> Result<()> {
        encode_compact_array_len(self.group_names.len(), buf)?;
        for name in &self.group_names {
            KafkaString::new(name).try_encode_compact(buf)?;
        }
        TaggedFields::default().try_encode(buf)?;
        Ok(())
    }
}

/// DeleteGroups response (API Key 42).
#[derive(Debug, Clone)]
pub struct DeleteGroupsResponse {
    /// Throttle time in milliseconds.
    pub throttle_time_ms: i32,
    /// Deletion results.
    pub results: Vec<DeletableGroupResult>,
}

/// Result for a single group deletion.
#[derive(Debug, Clone)]
pub struct DeletableGroupResult {
    /// Group ID.
    pub group_id: String,
    /// Error code.
    pub error_code: ErrorCode,
}

impl DeleteGroupsResponse {
    /// Decode from version 0–1 (non-flexible).
    pub fn decode_v0(buf: &mut impl Buf) -> Result<Self> {
        let throttle_time_ms = i32::decode(buf)?;
        let result_count = check_decode_array_len(i32::decode(buf)?)?;
        let mut results = Vec::with_capacity(result_count);

        for _ in 0..result_count {
            let group_id = non_nullable_string("group_id", KafkaString::decode(buf)?.0)?;
            let error_code = ErrorCode::from_i16(i16::decode(buf)?);
            results.push(DeletableGroupResult {
                group_id,
                error_code,
            });
        }

        Ok(Self {
            throttle_time_ms,
            results,
        })
    }

    /// Decode from version 2 (flexible encoding).
    pub fn decode_v2(buf: &mut impl Buf) -> Result<Self> {
        let throttle_time_ms = i32::decode(buf)?;
        let result_count =
            check_compact_array_len(crate::util::varint::decode_unsigned_varint(buf)?)?;
        let mut results = Vec::with_capacity(result_count);

        for _ in 0..result_count {
            let group_id = non_nullable_string("group_id", KafkaString::decode_compact(buf)?.0)?;
            let error_code = ErrorCode::from_i16(i16::decode(buf)?);
            let _ = TaggedFields::decode(buf)?;
            results.push(DeletableGroupResult {
                group_id,
                error_code,
            });
        }

        let _ = TaggedFields::decode(buf)?;

        Ok(Self {
            throttle_time_ms,
            results,
        })
    }
}

impl VersionedEncode for DeleteGroupsRequest {
    fn encode_versioned(&self, version: i16, buf: &mut impl BufMut) -> Result<()> {
        match version {
            0 | 1 => self.encode_v0(buf)?,
            2 => self.encode_v2(buf)?,
            _ => return unsupported_encode!("DeleteGroupsRequest", version),
        }
        Ok(())
    }
}

impl VersionedDecode for DeleteGroupsResponse {
    fn decode_versioned(version: i16, buf: &mut impl Buf) -> Result<Self> {
        match version {
            0 | 1 => Self::decode_v0(buf),
            2 => Self::decode_v2(buf),
            _ => unsupported_decode!("DeleteGroupsResponse", version),
        }
    }
}

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

    use crate::util::varint;
    use bytes::BytesMut;

    /// Helper: encode a compact string into `buf`.
    fn put_compact_string(buf: &mut BytesMut, s: Option<&str>) {
        match s {
            Some(val) => {
                buf.put_u8((val.len() + 1) as u8);
                buf.put_slice(val.as_bytes());
            }
            None => buf.put_u8(0),
        }
    }

    /// Helper: write empty tagged fields (varint 0).
    fn put_tagged_fields(buf: &mut BytesMut) {
        buf.put_u8(0);
    }

    #[test]
    fn test_delete_groups_request_encode_v0_round_trip() {
        let req = DeleteGroupsRequest::new(vec!["g1".to_string(), "g2".to_string()]);
        let mut buf = BytesMut::new();
        req.encode_v0(&mut buf).unwrap();

        let mut cur = &buf[..];
        assert_eq!(cur.get_i32(), 2); // 2 groups
        assert_eq!(cur.get_i16(), 2);
        let mut g = vec![0u8; 2];
        cur.copy_to_slice(&mut g);
        assert_eq!(g, b"g1");
        assert_eq!(cur.get_i16(), 2);
        cur.copy_to_slice(&mut g);
        assert_eq!(g, b"g2");
        assert!(cur.is_empty());
    }

    #[test]
    fn test_delete_groups_request_encode_v2_flexible() {
        let req = DeleteGroupsRequest::new(vec!["grp".to_string()]);
        let mut buf = BytesMut::new();
        req.encode_v2(&mut buf).unwrap();

        let mut cur = &buf[..];
        let arr = varint::decode_unsigned_varint(&mut cur).unwrap();
        assert_eq!(arr, 2); // 1 + 1
        let name_v = varint::decode_unsigned_varint(&mut cur).unwrap();
        assert_eq!(name_v, 4); // len("grp") + 1
        let mut g = vec![0u8; 3];
        cur.copy_to_slice(&mut g);
        assert_eq!(g, b"grp");
        assert_eq!(cur.get_u8(), 0); // tagged fields
        assert!(cur.is_empty());
    }

    #[test]
    fn test_delete_groups_response_decode_v0() {
        let mut buf = BytesMut::new();
        buf.put_i32(20); // throttle_time_ms
        buf.put_i32(2); // 2 results
        buf.put_i16(3);
        buf.put_slice(b"ga1");
        buf.put_i16(0); // NONE
        buf.put_i16(2);
        buf.put_slice(b"gb");
        buf.put_i16(69); // NON_EMPTY_GROUP

        let resp = DeleteGroupsResponse::decode_v0(&mut buf.freeze()).unwrap();
        assert_eq!(resp.throttle_time_ms, 20);
        assert_eq!(resp.results.len(), 2);
        assert_eq!(resp.results[0].group_id, "ga1");
        assert!(resp.results[0].error_code.is_ok());
        assert_eq!(resp.results[1].group_id, "gb");
        assert!(!resp.results[1].error_code.is_ok());
    }

    #[test]
    fn test_delete_groups_response_decode_v2_flexible() {
        let mut buf = BytesMut::new();
        buf.put_i32(0); // throttle_time_ms
        varint::encode_unsigned_varint(2, &mut buf); // 1 result
        put_compact_string(&mut buf, Some("mygroup"));
        buf.put_i16(0); // NONE
        put_tagged_fields(&mut buf); // result tagged fields
        put_tagged_fields(&mut buf); // top-level tagged fields

        let resp = DeleteGroupsResponse::decode_v2(&mut buf.freeze()).unwrap();
        assert_eq!(resp.results.len(), 1);
        assert_eq!(resp.results[0].group_id, "mygroup");
        assert!(resp.results[0].error_code.is_ok());
    }
}