kafrust_protocol/api/
metadata.rs

1use crate::codec::{Decoder, Encoder};
2use crate::error::Result;
3use crate::header::RequestHeader;
4
5pub const API_KEY: i16 = 3;
6
7#[derive(Debug, Clone, PartialEq, Eq)]
8pub struct MetadataRequestV1 {
9    pub correlation_id: i32,
10    pub client_id: Option<String>,
11    pub topics: Option<Vec<String>>,
12}
13
14impl MetadataRequestV1 {
15    pub fn encode(&self) -> Result<Vec<u8>> {
16        let mut encoder = Encoder::new();
17        RequestHeader {
18            api_key: API_KEY,
19            api_version: 1,
20            correlation_id: self.correlation_id,
21            client_id: self.client_id.clone(),
22        }
23        .encode_v1(&mut encoder)?;
24        encoder.write_array(self.topics.as_deref(), |encoder, topic| {
25            encoder.write_string(topic)
26        })?;
27        Ok(encoder.into_bytes())
28    }
29}
30
31#[derive(Debug, Clone, PartialEq, Eq)]
32pub struct BrokerMetadata {
33    pub node_id: i32,
34    pub host: String,
35    pub port: i32,
36    pub rack: Option<String>,
37}
38
39impl BrokerMetadata {
40    fn decode(decoder: &mut Decoder<'_>) -> Result<Self> {
41        Ok(Self {
42            node_id: decoder.read_i32()?,
43            host: decoder.read_string()?,
44            port: decoder.read_i32()?,
45            rack: decoder.read_nullable_string()?,
46        })
47    }
48}
49
50#[derive(Debug, Clone, PartialEq, Eq)]
51pub struct PartitionMetadata {
52    pub error_code: i16,
53    pub partition_index: i32,
54    pub leader_id: i32,
55    pub replica_nodes: Vec<i32>,
56    pub isr_nodes: Vec<i32>,
57}
58
59impl PartitionMetadata {
60    fn decode(decoder: &mut Decoder<'_>) -> Result<Self> {
61        Ok(Self {
62            error_code: decoder.read_i16()?,
63            partition_index: decoder.read_i32()?,
64            leader_id: decoder.read_i32()?,
65            replica_nodes: decoder
66                .read_array("replica nodes", |decoder| decoder.read_i32())?
67                .unwrap_or_default(),
68            isr_nodes: decoder
69                .read_array("isr nodes", |decoder| decoder.read_i32())?
70                .unwrap_or_default(),
71        })
72    }
73}
74
75#[derive(Debug, Clone, PartialEq, Eq)]
76pub struct TopicMetadata {
77    pub error_code: i16,
78    pub name: String,
79    pub is_internal: bool,
80    pub partitions: Vec<PartitionMetadata>,
81}
82
83impl TopicMetadata {
84    fn decode(decoder: &mut Decoder<'_>) -> Result<Self> {
85        Ok(Self {
86            error_code: decoder.read_i16()?,
87            name: decoder.read_string()?,
88            is_internal: decoder.read_bool()?,
89            partitions: decoder
90                .read_array("partitions", PartitionMetadata::decode)?
91                .unwrap_or_default(),
92        })
93    }
94}
95
96#[derive(Debug, Clone, PartialEq, Eq)]
97pub struct MetadataResponseV1 {
98    pub brokers: Vec<BrokerMetadata>,
99    pub controller_id: i32,
100    pub topics: Vec<TopicMetadata>,
101}
102
103impl MetadataResponseV1 {
104    pub fn decode_body(decoder: &mut Decoder<'_>) -> Result<Self> {
105        Ok(Self {
106            brokers: decoder
107                .read_array("brokers", BrokerMetadata::decode)?
108                .unwrap_or_default(),
109            controller_id: decoder.read_i32()?,
110            topics: decoder
111                .read_array("topics", TopicMetadata::decode)?
112                .unwrap_or_default(),
113        })
114    }
115}
116
117#[cfg(test)]
118#[allow(clippy::unwrap_used)]
119mod tests {
120    use super::{MetadataRequestV1, MetadataResponseV1, API_KEY};
121    use crate::codec::Decoder;
122
123    #[test]
124    fn encodes_metadata_request_v1_for_topics() {
125        let request = MetadataRequestV1 {
126            correlation_id: 9,
127            client_id: Some("kafrust".to_owned()),
128            topics: Some(vec!["orders".to_owned()]),
129        };
130
131        assert_eq!(
132            request.encode().unwrap(),
133            [
134                0, 3, // api key
135                0, 1, // api version
136                0, 0, 0, 9, // correlation id
137                0, 7, b'k', b'a', b'f', b'r', b'u', b's', b't', // client id
138                0, 0, 0, 1, // topics count
139                0, 6, b'o', b'r', b'd', b'e', b'r', b's', // topic name
140            ]
141        );
142        assert_eq!(API_KEY, 3);
143    }
144
145    #[test]
146    fn encodes_metadata_request_v1_for_all_topics() {
147        let request = MetadataRequestV1 {
148            correlation_id: 9,
149            client_id: None,
150            topics: None,
151        };
152
153        assert_eq!(
154            request.encode().unwrap(),
155            [
156                0, 3, // api key
157                0, 1, // api version
158                0, 0, 0, 9, // correlation id
159                0xff, 0xff, // null client id
160                0xff, 0xff, 0xff, 0xff, // null topics array
161            ]
162        );
163    }
164
165    #[test]
166    fn decodes_metadata_response_v1() {
167        let bytes = [
168            0, 0, 0, 1, // brokers count
169            0, 0, 0, 1, // node id
170            0, 9, b'l', b'o', b'c', b'a', b'l', b'h', b'o', b's', b't', // host
171            0, 0, 35, 132, // port 9092
172            0xff, 0xff, // null rack
173            0, 0, 0, 1, // controller id
174            0, 0, 0, 1, // topics count
175            0, 0, // topic error code
176            0, 6, b'o', b'r', b'd', b'e', b'r', b's', // topic name
177            0,    // is internal false
178            0, 0, 0, 1, // partition count
179            0, 0, // partition error code
180            0, 0, 0, 0, // partition index
181            0, 0, 0, 1, // leader id
182            0, 0, 0, 1, // replica count
183            0, 0, 0, 1, // replica node
184            0, 0, 0, 1, // isr count
185            0, 0, 0, 1, // isr node
186        ];
187
188        let mut decoder = Decoder::new(&bytes);
189        let response = MetadataResponseV1::decode_body(&mut decoder).unwrap();
190
191        assert_eq!(response.controller_id, 1);
192        assert_eq!(response.brokers.len(), 1);
193        assert_eq!(response.brokers[0].host, "localhost");
194        assert_eq!(response.brokers[0].port, 9092);
195        assert_eq!(response.topics.len(), 1);
196        assert_eq!(response.topics[0].name, "orders");
197        assert_eq!(response.topics[0].partitions[0].leader_id, 1);
198        assert_eq!(response.topics[0].partitions[0].replica_nodes, vec![1]);
199        assert_eq!(response.topics[0].partitions[0].isr_nodes, vec![1]);
200        assert!(decoder.is_empty());
201    }
202}
kafrust_protocol/api/metadata.rs

kafrust_protocol/api/
metadata.rs
