Stripes: Replace matplotlib by plotly

pyproject.toml

@@ -155,7 +155,9 @@ interpolation = [
   "utm>=0.7,<1",
 ]
 plotting = [
+  "kaleido>=0.2.1",
   "matplotlib>=3.3,<4",
+  "plotly>=5.24.1",
 ]
 mysql = [
   "mysqlclient>=2,<3",

wetterdienst/ui/cli.py

@@ -15,7 +15,6 @@
 import cloup
 from cloup import Section
 from cloup.constraints import If, RequireExactly, accept_none
-from PIL import Image
 
 from wetterdienst import Settings, Wetterdienst, __appname__, __version__
 from wetterdienst.ui.core import (
@@ -1279,12 +1278,10 @@ def stripes_values(
         if not target.name.lower().endswith(fmt):
             raise click.ClickException(f"'target' must have extension '{fmt}'")
 
-    import matplotlib.pyplot as plt
-
     set_logging_level(debug)
 
     try:
-        buf = _plot_stripes(
+        fig = _plot_stripes(
             kind=kind,
             station_id=station,
             name=name,
@@ -1294,21 +1291,16 @@ def stripes_values(
             show_title=show_title,
             show_years=show_years,
             show_data_availability=show_data_availability,
-            fmt=fmt,
-            dpi=dpi,
         )
     except Exception as e:
         log.exception(e)
         raise click.ClickException(str(e)) from e
 
     if target:
-        image = Image.open(buf, formats=["png"])
-        plt.imshow(image)
-        plt.axis("off")
-        plt.savefig(target, dpi=300, bbox_inches="tight")
+        fig.write_image(target, fmt, scale=dpi / 100)
         return
 
-    click.echo(buf.getvalue(), nl=False)
+    click.echo(fig.to_image(fmt, scale=dpi / 100), nl=False)
 
 
 @stripes.command("interactive")
@@ -1318,7 +1310,8 @@ def interactive(debug: bool):
 
     try:
         from wetterdienst.ui.streamlit.stripes import app
-    except ImportError:
+    except ImportError as e:
+        log.exception(e)
         log.error("Please install the stripes extras from stripes/requirements.txt")
         sys.exit(1)
 

wetterdienst/ui/core.py

@@ -5,8 +5,6 @@
 import json
 import logging
 import sys
-from concurrent.futures import ThreadPoolExecutor
-from io import BytesIO
 from typing import TYPE_CHECKING, Literal
 
 import polars as pl
@@ -20,6 +18,8 @@
 from wetterdienst.util.ui import read_list
 
 if TYPE_CHECKING:
+    from plotly.graph_objs import Figure
+
     from wetterdienst.core.timeseries.request import TimeseriesRequest
     from wetterdienst.core.timeseries.result import (
         InterpolatedValuesResult,
@@ -563,9 +563,7 @@ def _plot_stripes(
     show_title: bool = True,
     show_years: bool = True,
     show_data_availability: bool = True,
-    fmt: str | Literal["png", "jpg", "svg", "pdf"] = "png",
-    dpi: int = 100,
-) -> BytesIO:
+) -> Figure:
     """Create warming stripes for station in Germany.
     Code similar to: https://www.s4f-freiburg.de/temperaturstreifen/
     """
@@ -576,18 +574,12 @@ def _plot_stripes(
             raise ValueError("start_year must be less than end_year")
     if name_threshold < 0 or name_threshold > 1:
         raise ValueError("name_threshold must be between 0.0 and 1.0")
-    if dpi <= 0:
-        raise ValueError("dpi must be more than 0")
 
-    import matplotlib
-    import matplotlib.pyplot as plt
+    import plotly.graph_objects as go
 
     request = CLIMATE_STRIPES_CONFIG[kind]["request"]()
     cmap = CLIMATE_STRIPES_CONFIG[kind]["color_map"]
 
-    matplotlib.use("agg")
-    color_map = plt.get_cmap(cmap)
-
     if station_id:
         stations = request.filter_by_station_id(station_id)
     elif name:
@@ -614,9 +606,6 @@ def _plot_stripes(
         ),
         pl.when(pl.col("value").is_not_null()).then(-0.02).otherwise(None).alias("availability"),
     )
-    df = df.with_columns(
-        pl.col("value_scaled").map_elements(color_map, return_dtype=pl.List(pl.Float64)).alias("color")
-    )
 
     if start_year:
         df = df.filter(pl.col("date").dt.year().ge(start_year))
@@ -626,84 +615,77 @@ def _plot_stripes(
     if len(df) == 1:
         raise ValueError("At least two years are required to create warming stripes.")
 
-    fig, ax = plt.subplots(tight_layout=True)
-
     df_without_nulls = df.drop_nulls("value")
 
-    ax.bar(
-        df_without_nulls.get_column("date").dt.year(),
-        1.0,
-        width=1.0,
-        color=df_without_nulls.get_column("color"),
+    fig = go.Figure()
+
+    # Add bar trace
+    fig.add_trace(
+        go.Bar(
+            x=df_without_nulls.get_column("date").dt.year(),
+            y=[1.0] * len(df_without_nulls),
+            marker=dict(color=df_without_nulls.get_column("value_scaled"), colorscale=cmap, cmin=0, cmax=1),
+            width=1.0,
+        )
     )
-    ax.set_axis_off()
+
+    # Add scatter trace for data availability
     if show_data_availability:
-        ax.scatter(
-            df.get_column("date").dt.year(),
-            df.get_column("availability"),
-            color="gold",
-            marker=",",
-            s=0.5,
-        )
-        ax.plot(
-            df.get_column("date").dt.year(),
-            df.get_column("availability"),
-            color="gold",
+        fig.add_trace(
+            go.Scatter(
+                x=df.get_column("date").dt.year(),
+                y=df.get_column("availability"),
+                mode="lines",
+                marker=dict(color="gold", size=5),
+                line=dict(color="gold"),
+            )
         )
-        ax.text(
-            df.get_column("date").dt.year().min(),
-            -0.03,
-            "data availability",
-            ha="left",
-            va="top",
-            color="gold",
+        fig.add_annotation(
+            x=df.get_column("date").dt.year().min(),
+            xanchor="left",
+            y=-0.05,
+            text="data availability",
+            showarrow=False,
+            align="right",
+            font=dict(color="gold"),
         )
-    ax.text(0.5, -0.04, "Source: Deutscher Wetterdienst", ha="center", va="center", transform=ax.transAxes)
-
+    # Add source text
+    fig.add_annotation(
+        x=0.5, y=-0.05, text="Source: Deutscher Wetterdienst", showarrow=False, xref="paper", yref="paper"
+    )
     if show_title:
-        ax.set_title(f"""Climate stripes ({kind}) for {station_dict["name"]}, Germany ({station_dict["station_id"]})""")
+        fig.update_layout(
+            title=f"Climate stripes ({kind}) for {station_dict['name']}, Germany ({station_dict['station_id']})"
+        )
     if show_years:
-        ax.text(0.05, -0.05, df.get_column("date").min().year, ha="center", va="center", transform=ax.transAxes)
-        ax.text(0.95, -0.05, df.get_column("date").max().year, ha="center", va="center", transform=ax.transAxes)
-
-    buf = BytesIO()
-    plt.savefig(buf, format=fmt, dpi=dpi, bbox_inches="tight")
-    plt.close(fig)
-    buf.seek(0)
-
-    return buf
-
-
-def _thread_safe_plot_stripes(
-    kind: Literal["temperature", "precipitation"],
-    station_id: str | None = None,
-    name: str | None = None,
-    start_year: int | None = None,
-    end_year: int | None = None,
-    name_threshold: float = 0.9,
-    show_title: bool = True,
-    show_years: bool = True,
-    show_data_availability: bool = True,
-    fmt: str | Literal["png", "jpg", "svg", "pdf"] = "png",
-    dpi: int = 100,
-) -> BytesIO:
-    """Thread-safe wrapper for _plot_warming_stripes because matplotlib is not thread-safe."""
-    with ThreadPoolExecutor(1) as executor:
-        return executor.submit(
-            lambda: _plot_stripes(
-                kind=kind,
-                station_id=station_id,
-                name=name,
-                start_year=start_year,
-                end_year=end_year,
-                name_threshold=name_threshold,
-                show_title=show_title,
-                show_years=show_years,
-                show_data_availability=show_data_availability,
-                fmt=fmt,
-                dpi=dpi,
-            )
-        ).result()
+        fig.add_annotation(
+            x=0.05,
+            y=-0.05,
+            text=str(df.get_column("date").min().year),
+            showarrow=False,
+            xref="paper",
+            yref="paper",
+            xanchor="right",
+        )
+        fig.add_annotation(
+            x=0.95,
+            y=-0.05,
+            text=str(df.get_column("date").max().year),
+            showarrow=False,
+            xref="paper",
+            yref="paper",
+            xanchor="left",
+        )
+    fig.update_layout(
+        plot_bgcolor="white",
+        xaxis=dict(
+            showticklabels=False,
+        ),
+        yaxis=dict(range=[None, 1], showticklabels=False),
+        showlegend=False,
+        margin=dict(l=10, r=10, t=30, b=30),
+    )
+    return fig
 
 
 def set_logging_level(debug: bool):

wetterdienst/ui/restapi.py

@@ -32,7 +32,7 @@
     ValuesRequest,
     ValuesRequestRaw,
     _get_stripes_stations,
-    _thread_safe_plot_stripes,
+    _plot_stripes,
     get_interpolate,
     get_stations,
     get_summarize,
@@ -518,7 +518,7 @@ def stripes_values(
         )
 
     try:
-        buf = _thread_safe_plot_stripes(
+        fig = _plot_stripes(
             kind=kind,
             station_id=station,
             name=name,
@@ -528,14 +528,12 @@ def stripes_values(
             show_title=show_title,
             show_years=show_years,
             show_data_availability=show_data_availability,
-            fmt=fmt,
-            dpi=dpi,
         )
     except Exception as e:
         log.exception(e)
         raise HTTPException(status_code=400, detail=str(e)) from e
     media_type = f"image/{fmt}"
-    return Response(content=buf.getvalue(), media_type=media_type)
+    return Response(content=fig.to_image(fmt, scale=dpi / 100), media_type=media_type)
 
 
 def start_service(listen_address: str | None = None, reload: bool | None = False):  # pragma: no cover