Fingerprint frame layer previews

sample_data/boston_floods/ingest_mbta.py

@@ -6,6 +6,7 @@
 import requests
 
 from uvdat.core.models import NetworkNode, VectorData, VectorFeature
+from uvdat.core.tasks.run_mode import TaskRunMode
 
 LINE_COLORS = {
     "RED": "#D31414",
@@ -30,7 +31,7 @@ def convert_dataset(dataset, options):
         layer_options=options.get("layers"),
         network_options=options.get("network_options"),
         region_options=options.get("region_options"),
-        asynchronous=False,
+        run_mode=TaskRunMode.SYNC,
     )
 
     # Post-processing

sample_data/new_york_energy/ingest.py

@@ -3,6 +3,7 @@
 from pathlib import Path
 
 from uvdat.core.tasks.dataset import create_layers_and_frames
+from uvdat.core.tasks.run_mode import TaskRunMode
 
 from .export_networks import perform_export
 from .import_networks import perform_import
@@ -34,5 +35,5 @@ def convert_dataset(dataset, options):
             layer_options=options.get("layers"),
             network_options=options.get("network_options"),
             region_options=options.get("region_options"),
-            asynchronous=False,
+            run_mode=TaskRunMode.SYNC,
         )

uvdat/core/admin.py

@@ -19,6 +19,7 @@
     NetworkNode,
     Project,
     RasterData,
+    RasterFramePreview,
     Region,
     SizeConfig,
     SizeRangeConfig,
@@ -69,6 +70,20 @@ class LayerStyleAdmin(admin.ModelAdmin):
     list_display = ["id", "name", "layer"]
 
 
+@admin.register(RasterFramePreview)
+class RasterFramePreviewAdmin(admin.ModelAdmin):
+    list_display = [
+        "id",
+        "layer_frame",
+        "style_fingerprint",
+        "raster_style_params",
+        "width",
+        "height",
+        "status",
+    ]
+    list_select_related = ["layer_frame"]
+
+
 @admin.register(Colormap)
 class ColormapAdmin(admin.ModelAdmin):
     list_display = ["id", "name"]

uvdat/core/frame_previews/fingerprint.py

@@ -0,0 +1,23 @@
+from __future__ import annotations
+
+import hashlib
+import json
+from typing import TYPE_CHECKING, Any
+
+if TYPE_CHECKING:
+    from uvdat.core.models import LayerStyle
+
+
+def _fingerprint_payload(params: dict[str, Any] | None) -> str:
+    return json.dumps(params or {}, sort_keys=True, default=str)
+
+
+def params_fingerprint(params: dict[str, Any] | None) -> str:
+    """Sha256 of ``raster_style_params`` JSON used to render preview PNGs."""
+    payload = _fingerprint_payload(params)
+    return hashlib.sha256(payload.encode()).hexdigest()
+
+
+def style_fingerprint(layer_style: LayerStyle) -> str:
+    """Sha256 of a style's ``raster_style_params``."""
+    return params_fingerprint(layer_style.raster_style_params)

uvdat/core/frame_previews/lookup.py

@@ -0,0 +1,93 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from uvdat.core.frame_previews.fingerprint import params_fingerprint, style_fingerprint
+from uvdat.core.frame_previews.types import FramePreviewData
+from uvdat.core.models.frame_preview import PreviewStatus, RasterFramePreview
+
+if TYPE_CHECKING:
+    from uvdat.core.models import Layer, LayerFrame
+
+
+def serialize_frame_preview(preview: RasterFramePreview) -> FramePreviewData:
+    return FramePreviewData(
+        url=preview.image.url,
+        width=preview.width,
+        height=preview.height,
+        bounds=preview.bounds,
+    )
+
+
+def previews_by_frame_id(
+    frames: list[LayerFrame],
+    fingerprint: str,
+) -> dict[int, RasterFramePreview]:
+    """Return ``{frame_id: RasterFramePreview}`` for ``fingerprint``."""
+    if not frames:
+        return {}
+    return {
+        preview.layer_frame_id: preview
+        for preview in RasterFramePreview.objects.filter(
+            layer_frame_id__in=[frame.id for frame in frames],
+            style_fingerprint=fingerprint,
+        )
+    }
+
+
+def ordered_complete_previews(
+    layer: Layer,
+    fingerprint: str,
+) -> list[FramePreviewData] | None:
+    """Return serialized previews in frame order, or None if any frame is incomplete."""
+    if not layer.is_multiframe_raster():
+        return None
+
+    frames = layer.raster_frames()
+    by_frame = previews_by_frame_id(frames, fingerprint)
+    ordered = [by_frame.get(frame.id) for frame in frames]
+    if not all(
+        preview is not None and preview.status == PreviewStatus.COMPLETE and preview.image
+        for preview in ordered
+    ):
+        return None
+    return [serialize_frame_preview(preview) for preview in ordered]
+
+
+def preview_status_for_fingerprint(
+    layer: Layer,
+    fingerprint: str,
+) -> str | None:
+    if not layer.is_multiframe_raster():
+        return None
+
+    frames = layer.raster_frames()
+    by_frame = previews_by_frame_id(frames, fingerprint)
+    if all(
+        (preview := by_frame.get(frame.id))
+        and preview.status == PreviewStatus.COMPLETE
+        and preview.image
+        for frame in frames
+    ):
+        return "ready"
+    return "notready"
+
+
+def previews_current_for_fingerprint(layer: Layer, fingerprint: str) -> bool:
+    """Return whether every frame already has a complete preview for this fingerprint."""
+    return preview_status_for_fingerprint(layer, fingerprint) == "ready"
+
+
+def layer_default_fingerprint(layer: Layer) -> str:
+    """Fingerprint for layer-level default previews (default style params, else ``{}``)."""
+    if layer.default_style_id is not None:
+        return style_fingerprint(layer.default_style)
+    return params_fingerprint({})
+
+
+def layer_default_multiframe_previews(layer: Layer) -> list[FramePreviewData] | None:
+    """Previews for the layer default fingerprint (default style params or ``{}``)."""
+    return ordered_complete_previews(
+        layer,
+        layer_default_fingerprint(layer),
+    )