Residual Calculation for Web Service

fixes #31 (closed)

geomagio/api/ws/algorithms.py

-from fastapi import APIRouter, Depends
+from typing import List
+
+from fastapi import APIRouter, Depends, HTTPException
 from starlette.responses import Response
 
 from ... import TimeseriesFactory
 from ...algorithm import DbDtAlgorithm
+from ...residual import (
+    calculate,
+    Reading,
+    MARK_TYPES,
+    INCLINATION_TYPES,
+    DECLINATION_TYPES,
+)
 from .DataApiQuery import DataApiQuery
 from .data import format_timeseries, get_data_factory, get_data_query, get_timeseries
 
@@ -25,3 +34,28 @@ def get_dbdt(
     return format_timeseries(
         timeseries=timeseries, format=query.format, elements=elements
     )
+
+
+@router.post("/algorithms/residual", response_model=Reading)
+def calculate_residual(reading: Reading, adjust_reference: bool = True):
+    missing_types = get_missing_measurement_types(reading=reading)
+    if len(missing_types) != 0:
+        error_message = ", ".join(t.value for t in missing_types)
+        raise HTTPException(
+            status_code=400,
+            detail=f"Missing {error_message} measurements in input reading",
+        )
+    return calculate(reading=reading, adjust_reference=adjust_reference)
+
+
+def get_missing_measurement_types(reading: Reading) -> List[str]:
+    measurement_types = [m.measurement_type for m in reading.measurements]
+    missing_types = []
+    missing_types.extend(
+        [type for type in DECLINATION_TYPES if type not in measurement_types]
+    )
+    missing_types.extend(
+        [type for type in INCLINATION_TYPES if type not in measurement_types]
+    )
+    missing_types.extend([type for type in MARK_TYPES if type not in measurement_types])
+    return missing_types