refactor: use asyncpg instead of psycopg

Move sql query file next to indicator module where it is used.

PR: #876

Closes #746

Author: matthiasschaub

ohsome_quality_api/indicators/building_comparison/indicator.py

@@ -1,17 +1,15 @@
 import logging
 import os
+from pathlib import Path
 from string import Template
 
 import geojson
 import plotly.graph_objects as pgo
-import psycopg
 import yaml
-from async_lru import alru_cache
 from dateutil import parser
 from geojson import Feature
 from numpy import mean
 
-from ohsome_quality_api.config import get_config_value
 from ohsome_quality_api.definitions import Color, get_attribution
 from ohsome_quality_api.geodatabase import client as db_client
 from ohsome_quality_api.indicators.base import BaseIndicator
@@ -277,27 +275,18 @@ def format_sources(self):
 
 
 # alru needs hashable type, therefore, use string instead of Feature
-@alru_cache
+# @alru_cache
 async def get_reference_building_area(feature_str: str, table_name: str) -> float:
-    """Get the building area for a AoI from the EUBUCCO dataset."""
-    # TODO: https://github.com/GIScience/ohsome-quality-api/issues/746
-    file_path = os.path.join(db_client.WORKING_DIR, "select_building_area.sql")
-    with open(file_path, "r") as file:
+    path = Path(__file__).parent / "query.sql"
+    with open(path, "r") as file:
         query = file.read()
-    dns = "postgres://{user}:{password}@{host}:{port}/{database}".format(
-        host=get_config_value("postgres_host"),
-        port=get_config_value("postgres_port"),
-        database=get_config_value("postgres_db"),
-        user=get_config_value("postgres_user"),
-        password=get_config_value("postgres_password"),
-    )
     feature = geojson.loads(feature_str)
     geom = geojson.dumps(feature.geometry)
-    async with await psycopg.AsyncConnection.connect(dns) as con:
-        async with con.cursor() as cur:
-            await cur.execute(query.format(table_name=table_name), (geom,))
-            res = await cur.fetchone()
-    return res[0] or 0.0
+    results = await db_client.fetch(
+        query.format(table_name=table_name),
+        geom,
+    )
+    return results[0][0] or 0.0
 
 
 def load_datasets_metadata() -> dict:

ohsome_quality_api/geodatabase/select_building_area.sql renamed to ohsome_quality_api/indicators/building_comparison/query.sql

@@ -1,7 +1,7 @@
 WITH bpoly AS (
     SELECT
         -- split mutlipolygon into list of polygons for more efficient processing
-        (ST_DUMP (ST_Setsrid (ST_GeomFromGeoJSON (%s), 4326))).geom AS geom
+        (ST_DUMP (ST_Setsrid (ST_GeomFromGeoJSON ($1), 4326))).geom AS geom
 )
 SELECT
     SUM({table_name}.area) as area

ohsome_quality_api/indicators/road_comparison/indicator.py

@@ -1,15 +1,14 @@
 import logging
 import os
+from pathlib import Path
 
 import geojson
 import plotly.graph_objects as pgo
-import psycopg
 import yaml
 from async_lru import alru_cache
 from geojson import Feature
 from numpy import mean
 
-from ohsome_quality_api.config import get_config_value
 from ohsome_quality_api.definitions import Color, get_attribution
 from ohsome_quality_api.geodatabase import client as db_client
 from ohsome_quality_api.indicators.base import BaseIndicator
@@ -275,29 +274,17 @@ async def get_matched_roadlengths(
     feature_str: str,
     table_name: str,
 ) -> tuple[float, float]:
-    file_path = os.path.join(db_client.WORKING_DIR, "get_matched_roads.sql")
+    file_path = Path(__file__).parent / "query.sql"
     with open(file_path, "r") as file:
         query = file.read()
-    dns = "postgres://{user}:{password}@{host}:{port}/{database}".format(
-        host=get_config_value("postgres_host"),
-        port=get_config_value("postgres_port"),
-        database=get_config_value("postgres_db"),
-        user=get_config_value("postgres_user"),
-        password=get_config_value("postgres_password"),
-    )
     feature = geojson.loads(feature_str)
     table_name = table_name.replace(" ", "_")
     geom = geojson.dumps(feature.geometry)
-    async with await psycopg.AsyncConnection.connect(dns) as con:
-        async with con.cursor() as cur:
-            await cur.execute(
-                query.format(
-                    table_name=table_name,
-                ),
-                (geom,),
-            )
-            res = await cur.fetchone()
-    return res[0], res[1]
+    results = await db_client.fetch(
+        query.format(table_name=table_name),
+        geom,
+    )
+    return results[0][0], results[0][1]
 
 
 def load_datasets_metadata() -> dict:

ohsome_quality_api/geodatabase/get_matched_roads.sql renamed to ohsome_quality_api/indicators/road_comparison/query.sql

@@ -1,7 +1,7 @@
 WITH bpoly AS (
     SELECT
         -- split mutlipolygon into list of polygons for more efficient processing
-        (ST_DUMP (ST_Setsrid (ST_GeomFromGeoJSON (%s), 4326))).geom AS geom
+        (ST_DUMP (ST_Setsrid (ST_GeomFromGeoJSON ($1), 4326))).geom AS geom
 )
 SELECT
     SUM(cr.covered),