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
use std::sync::Arc;

use arrow::{array::ArrayData, pyarrow::ToPyArrow};
use dora_node_api::{
    dora_core::message::{ArrowTypeInfo, BufferOffset},
    merged::MergedEvent,
    Data, Event, Metadata, MetadataParameters,
};
use eyre::{Context, Result};
use pyo3::{
    exceptions::PyLookupError,
    prelude::*,
    types::{PyBytes, PyDict},
};

#[pyclass]
pub struct PyEvent {
    event: MergedEvent<PyObject>,
    data: Option<Arc<Data>>,
}

#[pymethods]
impl PyEvent {
    pub fn __getitem__(&self, key: &str, py: Python<'_>) -> PyResult<Option<PyObject>> {
        if key == "kind" {
            let kind = match &self.event {
                MergedEvent::Dora(_) => "dora",
                MergedEvent::External(_) => "external",
            };
            return Ok(Some(kind.to_object(py)));
        }
        match &self.event {
            MergedEvent::Dora(event) => {
                let value = match key {
                    "type" => Some(Self::ty(event).to_object(py)),
                    "id" => Self::id(event).map(|v| v.to_object(py)),
                    "data" => self.data(py),
                    "value" => self.value(py)?,
                    "metadata" => Self::metadata(event, py),
                    "error" => Self::error(event).map(|v| v.to_object(py)),
                    other => {
                        return Err(PyLookupError::new_err(format!(
                            "event has no property `{other}`"
                        )))
                    }
                };
                Ok(value)
            }
            MergedEvent::External(event) => event.call_method1(py, "__getitem__", (key,)).map(Some),
        }
    }

    pub fn inner(&mut self) -> Option<&PyObject> {
        match &self.event {
            MergedEvent::Dora(_) => None,
            MergedEvent::External(event) => Some(event),
        }
    }
}

impl PyEvent {
    fn ty(event: &Event) -> &str {
        match event {
            Event::Stop => "STOP",
            Event::Input { .. } => "INPUT",
            Event::InputClosed { .. } => "INPUT_CLOSED",
            Event::Error(_) => "ERROR",
            _other => "UNKNOWN",
        }
    }

    fn id(event: &Event) -> Option<&str> {
        match event {
            Event::Input { id, .. } => Some(id),
            Event::InputClosed { id } => Some(id),
            _ => None,
        }
    }

    /// Returns the payload of an input event as a `PyBytes` object (if any).
    fn data(&self, py: Python<'_>) -> Option<PyObject> {
        self.data.as_ref().map(|data| PyBytes::new(py, data).into())
    }

    /// Returns the payload of an input event as an arrow array (if any).
    fn value(&self, py: Python<'_>) -> PyResult<Option<PyObject>> {
        match (&self.event, &self.data) {
            (MergedEvent::Dora(Event::Input { metadata, .. }), Some(data)) => {
                let array = data
                    .clone()
                    .into_arrow_array(&metadata.type_info)
                    .context("Could not create arrow array")?;
                // TODO: Does this call leak data?
                let array_data = array.to_pyarrow(py)?;
                Ok(Some(array_data))
            }
            _ => Ok(None),
        }
    }

    fn metadata(event: &Event, py: Python<'_>) -> Option<PyObject> {
        match event {
            Event::Input { metadata, .. } => Some(metadata_to_pydict(metadata, py).to_object(py)),
            _ => None,
        }
    }

    fn error(event: &Event) -> Option<&str> {
        match event {
            Event::Error(error) => Some(error),
            _other => None,
        }
    }
}

impl From<Event> for PyEvent {
    fn from(event: Event) -> Self {
        Self::from(MergedEvent::Dora(event))
    }
}

impl From<MergedEvent<PyObject>> for PyEvent {
    fn from(mut event: MergedEvent<PyObject>) -> Self {
        let data = if let MergedEvent::Dora(Event::Input { data, .. }) = &mut event {
            data.take().map(Arc::new)
        } else {
            None
        };
        Self { event, data }
    }
}

pub fn pydict_to_metadata(dict: Option<&PyDict>) -> Result<MetadataParameters> {
    let mut default_metadata = MetadataParameters::default();
    if let Some(metadata) = dict {
        for (key, value) in metadata.iter() {
            match key.extract::<&str>().context("Parsing metadata keys")? {
                "watermark" => {
                    default_metadata.watermark =
                        value.extract().context("parsing watermark failed")?;
                }
                "deadline" => {
                    default_metadata.deadline =
                        value.extract().context("parsing deadline failed")?;
                }
                "open_telemetry_context" => {
                    let otel_context: &str = value
                        .extract()
                        .context("parsing open telemetry context failed")?;
                    default_metadata.open_telemetry_context = otel_context.to_string();
                }
                _ => (),
            }
        }
    }
    Ok(default_metadata)
}

pub fn metadata_to_pydict<'a>(metadata: &'a Metadata, py: Python<'a>) -> &'a PyDict {
    let dict = PyDict::new(py);
    dict.set_item(
        "open_telemetry_context",
        &metadata.parameters.open_telemetry_context,
    )
    .wrap_err("could not make metadata a python dictionary item")
    .unwrap();
    dict
}

pub fn copy_array_into_sample(
    target_buffer: &mut [u8],
    arrow_array: &ArrayData,
) -> eyre::Result<ArrowTypeInfo> {
    let mut next_offset = 0;
    copy_array_into_sample_inner(target_buffer, &mut next_offset, arrow_array)
}

fn copy_array_into_sample_inner(
    target_buffer: &mut [u8],
    next_offset: &mut usize,
    arrow_array: &ArrayData,
) -> eyre::Result<ArrowTypeInfo> {
    let mut buffer_offsets = Vec::new();
    for buffer in arrow_array.buffers().iter() {
        let len = buffer.len();
        assert!(
            target_buffer[*next_offset..].len() >= len,
            "target buffer too small (total_len: {}, offset: {}, required_len: {len})",
            target_buffer.len(),
            *next_offset,
        );
        target_buffer[*next_offset..][..len].copy_from_slice(buffer.as_slice());
        buffer_offsets.push(BufferOffset {
            offset: *next_offset,
            len,
        });
        *next_offset += len;
    }

    let mut child_data = Vec::new();
    for child in arrow_array.child_data() {
        let child_type_info = copy_array_into_sample_inner(target_buffer, next_offset, child)?;
        child_data.push(child_type_info);
    }

    Ok(ArrowTypeInfo {
        data_type: arrow_array.data_type().clone(),
        len: arrow_array.len(),
        null_count: arrow_array.null_count(),
        validity: arrow_array.nulls().map(|b| b.validity().to_owned()),
        offset: arrow_array.offset(),
        buffer_offsets,
        child_data,
    })
}

pub fn required_data_size(array: &ArrayData) -> usize {
    let mut size = 0;
    for buffer in array.buffers() {
        size += buffer.len();
    }
    for child in array.child_data() {
        size += required_data_size(child);
    }
    size
}