src/backend/gradio_rerun/rerun.py

"""gr.SimpleImage() component."""

from __future__ import annotations

from pathlib import Path
from typing import Any, Callable

from gradio_client import file
from gradio import processing_utils
from gradio.components.base import Component, StreamingOutput
from gradio.data_classes import GradioRootModel, FileData
from gradio.events import Events


class RerunData(GradioRootModel):
    """
    Data model for Rerun component is a list of data sources.

    `FileData` is used for data served from Gradio, while `str` is used for URLs Rerun will open from a remote server.
    """

    root: list[FileData | str]


class Rerun(Component, StreamingOutput):
    """
    Creates a Rerun viewer component that can be used to display the output of a Rerun stream.
    """

    EVENTS: list[Events] = []

    data_model = RerunData

    def __init__(
        self,
        value: list[Path | str] | Path | str | bytes | Callable | None = None,
        *,
        label: str | None = None,
        every: float | None = None,
        show_label: bool | None = None,
        container: bool = True,
        scale: int | None = None,
        min_width: int = 160,
        height: int | str = 640,
        visible: bool = True,
        streaming: bool = False,
        elem_id: str | None = None,
        elem_classes: list[str] | str | None = None,
        render: bool = True,
    ):
        """
        Parameters:
            value: Takes a singular or list of RRD resources. Each RRD can be a Path, a string containing a url, or a binary blob containing encoded RRD data. If callable, the function will be called whenever the app loads to set the initial value of the component.
            label: The label for this component. Appears above the component and is also used as the header if there are a table of examples for this component. If None and used in a `gr.Interface`, the label will be the name of the parameter this component is assigned to.
            every: If `value` is a callable, run the function 'every' number of seconds while the client connection is open. Has no effect otherwise. Queue must be enabled. The event can be accessed (e.g. to cancel it) via this component's .load_event attribute.
            show_label: if True, will display label.
            container: If True, will place the component in a container - providing some extra padding around the border.
            scale: relative size compared to adjacent Components. For example if Components A and B are in a Row, and A has scale=2, and B has scale=1, A will be twice as wide as B. Should be an integer. scale applies in Rows, and to top-level Components in Blocks where fill_height=True.
            min_width: minimum pixel width, will wrap if not sufficient screen space to satisfy this value. If a certain scale value results in this Component being narrower than min_width, the min_width parameter will be respected first.
            height: height of component in pixels. If a string is provided, will be interpreted as a CSS value. If None, will be set to 640px.
            visible: If False, component will be hidden.
            streaming: If True, the data should be incrementally yielded from the source as `bytes` returned by calling `.read()` on an `rr.binary_stream()`
            elem_id: An optional string that is assigned as the id of this component in the HTML DOM. Can be used for targeting CSS styles.
            elem_classes: An optional list of strings that are assigned as the classes of this component in the HTML DOM. Can be used for targeting CSS styles.
            render: If False, component will not render be rendered in the Blocks context. Should be used if the intention is to assign event listeners now but render the component later.
        """
        self.height = height
        self.streaming = streaming
        super().__init__(
            label=label,
            every=every,
            show_label=show_label,
            container=container,
            scale=scale,
            min_width=min_width,
            interactive=False,  # Rerun is an output-component only
            visible=visible,
            elem_id=elem_id,
            elem_classes=elem_classes,
            render=render,
            value=value,
        )

    def preprocess(self, payload: RerunData | None) -> RerunData | None:
        """
        This component does not accept input.

        Parameters:
            payload: A RerunData object.
        Returns:
            A RerunData object.
        """
        if payload is None:
            return None
        return payload

    def postprocess(
        self, value: list[Path | str] | Path | str | bytes
    ) -> RerunData | bytes:
        """
        Parameters:
            value: Expects
        Returns:
            A FileData object containing the image data.
        """
        if value is None:
            return RerunData(root=[])

        if isinstance(value, bytes):
            if self.streaming:
                return value
            file_path = processing_utils.save_bytes_to_cache(
                value, "rrd", cache_dir=self.GRADIO_CACHE
            )
            return RerunData(root=[FileData(path=file_path)])

        if not isinstance(value, list):
            value = [value]

        def is_url(input: Path | str) -> bool:
            if isinstance(input, Path):
                return False
            return input.startswith("http://") or input.startswith("https://")

        return RerunData(
            root=[
                FileData(
                    path=str(file),
                    orig_name=Path(file).name,
                    size=Path(file).stat().st_size,
                )
                if not is_url(file)
                else file
                for file in value
            ]
        )

    def stream_output(
        self, value, output_id: str, first_chunk: bool
    ) -> tuple[bytes | None, Any]:
        output_file = {
            "path": output_id,
            "is_stream": True,
        }
        if value is None:
            return None, output_file
        return value, output_file

    def check_streamable(self):
        return self.streaming

    def example_payload(self) -> Any:
        return []

    def example_value(self) -> Any:
        return [
            "https://app.rerun.io/version/0.16.0/examples/detect_and_track_objects.rrd",
            "https://app.rerun.io/version/0.16.0/examples/dna.rrd",
        ]