dora-message 0.5.0

`dora` goal is to be a low latency, composable, and distributed data flow.
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

use std::collections::BTreeMap;

use arrow_schema::DataType;
use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
pub struct Metadata {
    metadata_version: u16,
    timestamp: uhlc::Timestamp,
    pub type_info: ArrowTypeInfo,
    pub parameters: MetadataParameters,
}

impl Metadata {
    pub fn new(timestamp: uhlc::Timestamp, type_info: ArrowTypeInfo) -> Self {
        Self::from_parameters(timestamp, type_info, Default::default())
    }

    pub fn from_parameters(
        timestamp: uhlc::Timestamp,
        type_info: ArrowTypeInfo,
        parameters: MetadataParameters,
    ) -> Self {
        Self {
            metadata_version: 0,
            timestamp,
            parameters,
            type_info,
        }
    }

    pub fn timestamp(&self) -> uhlc::Timestamp {
        self.timestamp
    }

    pub fn open_telemetry_context(&self) -> String {
        if let Some(Parameter::String(otel)) = self.parameters.get("open_telemetry_context") {
            otel.to_string()
        } else {
            "".to_string()
        }
    }
}

pub type MetadataParameters = BTreeMap<String, Parameter>;

#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct ArrowTypeInfo {
    pub data_type: DataType,
    pub len: usize,
    pub null_count: usize,
    pub validity: Option<Vec<u8>>,
    pub offset: usize,
    pub buffer_offsets: Vec<BufferOffset>,
    pub child_data: Vec<ArrowTypeInfo>,
}

#[derive(Debug, PartialEq, Clone, Serialize, Deserialize)]
pub enum Parameter {
    Bool(bool),
    Integer(i64),
    String(String),
    ListInt(Vec<i64>),
    Float(f64),
    ListFloat(Vec<f64>),
    ListString(Vec<String>),
}

#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct BufferOffset {
    pub offset: usize,
    pub len: usize,
}