Fix2 electricity price prediction. (#296)

Normalize electricity price prediction to €/Wh.
Provide electricity price prediction by €/kWh for convenience.

Allow to configure electricity price charges by €/kWh.

Also added error page to fastapi rest server to get rid of annoying
unrelated fault messages during testing.

Signed-off-by: Bobby Noelte <b0661n0e17e@gmail.com>

src/akkudoktoreos/data/default.config.json

@@ -6,7 +6,7 @@
   "data_folder_path": null,
   "data_output_path": null,
   "data_output_subpath": null,
-  "elecprice_charges": 0.21,
+  "elecprice_charges_kwh": 0.21,
   "elecprice_provider": null,
   "elecpriceimport_file_path": null,
   "latitude": 52.5,
@@ -102,6 +102,7 @@
   "pvforecast4_userhorizon": null,
   "pvforecast_provider": null,
   "pvforecastimport_file_path": null,
+  "server_fastapi_startup_server_fasthtml": true,
   "server_fastapi_host": "0.0.0.0",
   "server_fastapi_port": 8503,
   "server_fasthtml_host": "0.0.0.0",

src/akkudoktoreos/devices/devices.py

@@ -211,8 +211,8 @@ class Devices(SingletonMixin, DevicesBase):
             interval=simulation_step,
         )
         # strompreis_euro_pro_wh[stunde]
-        elecprice_marketprice = self.prediction.key_to_array(
-            "elecprice_marketprice",
+        elecprice_marketprice_wh = self.prediction.key_to_array(
+            "elecprice_marketprice_wh",
             start_datetime=self.start_datetime,
             end_datetime=self.end_datetime,
             interval=simulation_step,

src/akkudoktoreos/prediction/elecprice.py

@@ -9,6 +9,6 @@ class ElecPriceCommonSettings(SettingsBaseModel):
     elecprice_provider: Optional[str] = Field(
         default=None, description="Electricity price provider id of provider to be used."
     )
-    elecprice_charges: Optional[float] = Field(
+    elecprice_charges_kwh: Optional[float] = Field(
         default=None, ge=0, description="Electricity price charges (€/kWh)."
     )

src/akkudoktoreos/prediction/elecpriceabc.py

@@ -7,7 +7,7 @@ Notes:
 from abc import abstractmethod
 from typing import List, Optional
 
-from pydantic import Field
+from pydantic import Field, computed_field
 
 from akkudoktoreos.prediction.predictionabc import PredictionProvider, PredictionRecord
 from akkudoktoreos.utils.logutil import get_logger
@@ -23,10 +23,22 @@ class ElecPriceDataRecord(PredictionRecord):
 
     """
 
-    elecprice_marketprice: Optional[float] = Field(
-        None, description="Electricity market price (€/KWh)"
+    elecprice_marketprice_wh: Optional[float] = Field(
+        None, description="Electricity market price per Wh (€/Wh)"
     )
 
+    # Computed fields
+    @computed_field  # type: ignore[prop-decorator]
+    @property
+    def elecprice_marketprice_kwh(self) -> Optional[float]:
+        """Electricity market price per kWh (€/kWh).
+
+        Convenience attribute calculated from `elecprice_marketprice_wh`.
+        """
+        if self.elecprice_marketprice_wh is None:
+            return None
+        return self.elecprice_marketprice_wh * 1000.0
+
 
 class ElecPriceProvider(PredictionProvider):
     """Abstract base class for electricity price providers.

src/akkudoktoreos/prediction/elecpriceakkudoktor.py

@@ -134,7 +134,7 @@ class ElecPriceAkkudoktor(ElecPriceProvider):
         prices_of_hour = self.elecprice_8days[hour]
         if np.isnan(prices_of_hour).all():
             # No prediction prices available for this hour - use mean value of all prices
-            price_weighted_mean = np.nanmean(self.elecprice_marketprice_8day)
+            price_weighted_mean = np.nanmean(self.elecprice_marketprice_wh_8day)
         else:
             weights = self.elecprice_8days_weights_day_of_week[day_of_week]
             prices_of_hour_masked: NDArray[Shape["24"]] = np.ma.MaskedArray(
@@ -204,24 +204,28 @@ class ElecPriceAkkudoktor(ElecPriceProvider):
         elecprice_cache_file.seek(0)
         self.elecprice_8days = np.load(elecprice_cache_file)
 
-        # Get elecprice_charges
-        charges = self.config.elecprice_charges if self.config.elecprice_charges else 0.0
+        # Get elecprice_charges_kwh_kwh
+        charges_kwh = (
+            self.config.elecprice_charges_kwh if self.config.elecprice_charges_kwh else 0.0
+        )
 
         for i in range(values_len):
             original_datetime = akkudoktor_data.values[i].start
             dt = to_datetime(original_datetime, in_timezone=self.config.timezone)
             akkudoktor_value = akkudoktor_data.values[i]
-            price = akkudoktor_value.marketpriceEurocentPerKWh / 100 + charges
+            price_wh = (
+                akkudoktor_value.marketpriceEurocentPerKWh / (100 * 1000) + charges_kwh / 1000
+            )
 
             if compare_datetimes(dt, self.start_datetime).lt:
                 # forecast data is too old
-                self.elecprice_8days[dt.hour, dt.day_of_week] = price
+                self.elecprice_8days[dt.hour, dt.day_of_week] = price_wh
                 continue
-            self.elecprice_8days[dt.hour, 7] = price
+            self.elecprice_8days[dt.hour, 7] = price_wh
 
             record = ElecPriceDataRecord(
                 date_time=dt,
-                elecprice_marketprice=price,
+                elecprice_marketprice_wh=price_wh,
             )
             self.append(record)
 
@@ -242,7 +246,7 @@ class ElecPriceAkkudoktor(ElecPriceProvider):
 
             record = ElecPriceDataRecord(
                 date_time=dt,
-                elecprice_marketprice=value,
+                elecprice_marketprice_wh=value,
             )
             self.insert(0, record)
         # Assure price ends at end_time
@@ -253,6 +257,6 @@ class ElecPriceAkkudoktor(ElecPriceProvider):
 
             record = ElecPriceDataRecord(
                 date_time=dt,
-                elecprice_marketprice=value,
+                elecprice_marketprice_wh=value,
             )
             self.append(record)

src/akkudoktoreos/server/fastapi_server.py

@@ -11,7 +11,7 @@ import pandas as pd
 import uvicorn
 from fastapi import FastAPI, Query, Request
 from fastapi.exceptions import HTTPException
-from fastapi.responses import FileResponse, RedirectResponse, Response
+from fastapi.responses import FileResponse, HTMLResponse, RedirectResponse, Response
 
 from akkudoktoreos.config.config import ConfigEOS, SettingsEOS, get_config
 from akkudoktoreos.core.ems import get_ems
@@ -37,6 +37,98 @@ measurement_eos = get_measurement()
 prediction_eos = get_prediction()
 ems_eos = get_ems()
 
+ERROR_PAGE_TEMPLATE = """
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Energy Optimization System (EOS) Error</title>
+    <style>
+        body {
+            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
+            background-color: #f5f5f5;
+            display: flex;
+            justify-content: center;
+            align-items: center;
+            height: 100vh;
+            margin: 0;
+            padding: 20px;
+            box-sizing: border-box;
+        }
+        .error-container {
+            background: white;
+            padding: 2rem;
+            border-radius: 8px;
+            box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+            max-width: 500px;
+            width: 100%;
+            text-align: center;
+        }
+        .error-code {
+            font-size: 4rem;
+            font-weight: bold;
+            color: #e53e3e;
+            margin: 0;
+        }
+        .error-title {
+            font-size: 1.5rem;
+            color: #2d3748;
+            margin: 1rem 0;
+        }
+        .error-message {
+            color: #4a5568;
+            margin-bottom: 1.5rem;
+        }
+        .error-details {
+            background: #f7fafc;
+            padding: 1rem;
+            border-radius: 4px;
+            margin-bottom: 1.5rem;
+            text-align: left;
+            font-family: monospace;
+            white-space: pre-wrap;
+            word-break: break-word;
+        }
+        .back-button {
+            background: #3182ce;
+            color: white;
+            border: none;
+            padding: 0.75rem 1.5rem;
+            border-radius: 4px;
+            text-decoration: none;
+            display: inline-block;
+            transition: background-color 0.2s;
+        }
+        .back-button:hover {
+            background: #2c5282;
+        }
+    </style>
+</head>
+<body>
+    <div class="error-container">
+        <h1 class="error-code">STATUS_CODE</h1>
+        <h2 class="error-title">ERROR_TITLE</h2>
+        <p class="error-message">ERROR_MESSAGE</p>
+        <div class="error-details">ERROR_DETAILS</div>
+        <a href="/docs" class="back-button">Back to Home</a>
+    </div>
+</body>
+</html>
+"""
+
+
+def create_error_page(
+    status_code: str, error_title: str, error_message: str, error_details: str
+) -> str:
+    """Create an error page by replacing placeholders in the template."""
+    return (
+        ERROR_PAGE_TEMPLATE.replace("STATUS_CODE", status_code)
+        .replace("ERROR_TITLE", error_title)
+        .replace("ERROR_MESSAGE", error_message)
+        .replace("ERROR_DETAILS", error_details)
+    )
+
 
 def start_fasthtml_server() -> subprocess.Popen:
     """Start the fasthtml server as a subprocess."""
@@ -301,10 +393,11 @@ def fastapi_prediction_list_get(
 
 @app.get("/strompreis")
 def fastapi_strompreis() -> list[float]:
-    """Deprecated: Electricity Market Price Prediction.
+    """Deprecated: Electricity Market Price Prediction per Wh (€/Wh).
 
     Note:
-        Use '/v1/prediction/list?key=elecprice_marketprice' instead.
+        Use '/v1/prediction/list?key=elecprice_marketprice_wh' or
+            '/v1/prediction/list?key=elecprice_marketprice_kwh' instead.
     """
     settings = SettingsEOS(
         elecprice_provider="ElecPriceAkkudoktor",
@@ -318,7 +411,7 @@ def fastapi_strompreis() -> list[float]:
     # Get the current date and the end date based on prediction hours
     # Fetch prices for the specified date range
     return prediction_eos.key_to_array(
-        key="elecprice_marketprice",
+        key="elecprice_marketprice_wh",
         start_datetime=prediction_eos.start_datetime,
         end_datetime=prediction_eos.end_datetime,
     ).tolist()
@@ -513,7 +606,7 @@ async def proxy_put(request: Request, path: str) -> Response:
     return await proxy(request, path)
 
 
-async def proxy(request: Request, path: str) -> Union[Response | RedirectResponse]:
+async def proxy(request: Request, path: str) -> Union[Response | RedirectResponse | HTMLResponse]:
     if config_eos.server_fasthtml_host and config_eos.server_fasthtml_port:
         # Proxy to fasthtml server
         url = f"http://{config_eos.server_fasthtml_host}:{config_eos.server_fasthtml_port}/{path}"
@@ -521,15 +614,31 @@ async def proxy(request: Request, path: str) -> Union[Response | RedirectRespons
 
         data = await request.body()
 
-        async with httpx.AsyncClient() as client:
-            if request.method == "GET":
-                response = await client.get(url, headers=headers)
-            elif request.method == "POST":
-                response = await client.post(url, headers=headers, content=data)
-            elif request.method == "PUT":
-                response = await client.put(url, headers=headers, content=data)
-            elif request.method == "DELETE":
-                response = await client.delete(url, headers=headers, content=data)
+        try:
+            async with httpx.AsyncClient() as client:
+                if request.method == "GET":
+                    response = await client.get(url, headers=headers)
+                elif request.method == "POST":
+                    response = await client.post(url, headers=headers, content=data)
+                elif request.method == "PUT":
+                    response = await client.put(url, headers=headers, content=data)
+                elif request.method == "DELETE":
+                    response = await client.delete(url, headers=headers, content=data)
+        except Exception as e:
+            error_page = create_error_page(
+                status_code="404",
+                error_title="Page Not Found",
+                error_message=f"""<pre>
+Application server not reachable: '{url}'
+Did you start the application server
+or set 'server_fastapi_startup_server_fasthtml'?
+If there is no application server intended please
+set 'server_fasthtml_host' or 'server_fasthtml_port' to None.
+</pre>
+""",
+                error_details=f"{e}",
+            )
+            return HTMLResponse(content=error_page, status_code=404)
 
         return Response(
             content=response.content,