Implement config file loader

Changes:

* Implement config file loader

* Add config-based database connector

bin/xmet-afos-ingest

@@ -2,22 +2,24 @@
 
 import argparse
 
+from xmet.config import Config
 from xmet.db     import Database
 from xmet.afos   import AFOSMessageParser
 from xmet.util   import each_chunk
 
+parser = argparse.ArgumentParser(
     description = 'Ingest National Weather Service text bulletin products'
 )
 
 parser.add_argument('--quiet',   action='store_true', help='Suppress output')
 parser.add_argument('--dry-run', action='store_true', help='Do not actually ingest products')
 
-parser.add_argument('db',             help='XMET SQLite3 database')
 parser.add_argument('afos-text-file', help='AFOS text bulletin product file')
 
 args = parser.parse_args()
 
-db = Database.connect(args.db)
+config = Config.load()
+db     = Database.from_config(config)
 db.execute('begin transaction')
 
 parser = AFOSMessageParser()

bin/xmet-event-ingest

@@ -2,6 +2,7 @@
 
 import argparse
 
+from xmet.config import Config
 from xmet.db     import Database
 from xmet.storm  import StormEvent
 
@@ -11,12 +12,12 @@ parser = argparse.ArgumentParser(
 
 parser.add_argument('--quiet',   action='store_true', help='Suppress output')
 parser.add_argument('--dry-run', action='store_true', help='Do not actually ingest events')
-parser.add_argument('db',                             help='XMET SQLite3 database')
 parser.add_argument('csv-event-details', nargs='+',   help='Compressed storm event details CSV file')
 
 args = parser.parse_args()
 
-db = Database.connect(args.db)
+config = Config.load()
+db     = Database.from_config(config)
 
 if not args.dry_run:
     db.execute('begin transaction')

bin/xmet-igra-ingest

@@ -2,6 +2,7 @@
 
 import argparse
 
+from xmet.config import Config
 from xmet.db     import Database
 from xmet.igra   import IGRAReader
 
@@ -17,7 +18,8 @@ parser.add_argument('igra-sounding-file', nargs='+', help='IGRA sounding file')
 
 args = parser.parse_args()
 
-db = Database.connect(args.db)
+config = Config.load()
+db     = Database.from_config(config)
 
 if not args.dry_run:
     db.execute('begin transaction')

bin/xmet-nexrad-archive

@@ -2,6 +2,7 @@
 
 import argparse
 
+from xmet.config  import Config
 from xmet.db      import Database
 from xmet.s3      import S3Bucket
 from xmet.storm   import StormEvent
@@ -18,13 +19,13 @@ group = parser.add_mutually_exclusive_group()
 group.add_argument('--exclude', action='append', type=str, help='Exclude types of events from ingest')
 group.add_argument('--type',    action='append', type=str, help='Specify only given types of events to ingest')
 
-parser.add_argument('db',                            help='XMET SQLite3 database')
 parser.add_argument('csv-event-details',  nargs='+', help='Compressed storm event details CSV file')
 parser.add_argument('archive-dir',                   help='Target archive directory')
 
 args = parser.parse_args()
 
-db      = Database.connect(args.db)
+config  = Config.load()
+db      = Database.from_config(config)
 bucket  = S3Bucket()
 archive = Archive(getattr(args, 'archive-dir'), bucket)
 exclude = None

bin/xmet-raob-ingest

@@ -2,6 +2,7 @@
 
 import argparse
 
+from xmet.config import Config
 from xmet.db     import Database
 from xmet.raob   import RAOBReader
 from xmet.igra   import IGRAStation
@@ -13,12 +14,12 @@ parser = argparse.ArgumentParser(
 parser.add_argument('--quiet',   action='store_true', help='Suppress output')
 parser.add_argument('--dry-run', action='store_true', help='Do not actually ingest data')
 
-parser.add_argument('db',                            help='XMET SQLite3 database')
 parser.add_argument('raob-sounding-file', nargs='+', help='RAOB sounding file')
 
 args = parser.parse_args()
 
-db = Database.connect(args.db)
+config = Config.load()
+db     = Database.from_config(config)
 
 if not args.dry_run:
     db.execute('begin transaction')

bin/xmet-sounding-plot

@@ -4,6 +4,7 @@ import argparse
 import cairo
 import shapely
 
+from xmet.config    import Config
 from xmet.db        import Database
 from xmet.sounding  import Sounding
 from xmet.skew_t    import SkewTGraph, SkewTLegend
@@ -60,14 +61,14 @@ parser = argparse.ArgumentParser(
 parser.add_argument('--skew-t',    type=str, help='Plot a Skew-T chart to the specified SVG file')
 parser.add_argument('--hodograph', type=str, help='Plot a hodograph to the specified SVG file')
 
-parser.add_argument('db',        help='XMET SQLite3 database')
 parser.add_argument('lat',       help='Latitude')
 parser.add_argument('lon',       help='Longitude')
 parser.add_argument('timestamp', help='Timestamp in YYYY-MM-DD HH:MM:SS (UTC)')
 
 args = parser.parse_args()
 
-db = Database.connect(args.db)
+config = Config.load()
+db     = Database.from_config(config)
 
 location = shapely.Point(float(args.lon), float(args.lat))
 sounding = Sounding.valid_by_location(db, location, args.timestamp)

bin/xmet-spc-render-file

@@ -3,6 +3,7 @@
 import argparse
 import cairo
 
+from xmet.config import Config
 from xmet.db     import Database
 
 from xmet.spc import SPCOutlookParser, \
@@ -25,7 +26,8 @@ ASSETS = {
 def render_categorical(conus: SPCOutlookMap,
                        outlook: SPCOutlook,
                        args):
-    db = Database.connect(args.db)
+    config = Config.load()
+    db     = Database.from_config(config)
 
     assets = ASSETS['dark'] if args.dark else ASSETS['light']
 
@@ -48,7 +50,8 @@ def render_probabilistic(conus: SPCOutlookMap,
                          hazard: str,
                          path: str,
                          args):
-    db = Database.connect(args.db)
+    config = Config.load()
+    db     = Database.from_config(config)
 
     assets = ASSETS['dark'] if args.dark else ASSETS['light']
 
@@ -69,7 +72,6 @@ def render_probabilistic(conus: SPCOutlookMap,
         conus.draw_annotation(cr, outlook, SPCOutlookType.PROBABILISTIC, hazard)
 
 argparser = argparse.ArgumentParser(description='Render graphical SPC outlooks from text file')
-argparser.add_argument('db',                          help='Spatialite database file')
 argparser.add_argument('--dark', action='store_true', help='Output dark mode graphics')
 argparser.add_argument('--categorical', type=str, help='Output categorical risk graphic file')
 argparser.add_argument('--any-severe',  type=str, help='Output probabilistic severe risk graphic file')

lib/xmet/config.py

@@ -0,0 +1,36 @@
+import os
+import configparser
+
+from typing import Optional, Self
+
+class ConfigException(Exception):
+    ...
+
+class ConfigFileException(ConfigException):
+    ...
+
+class Config(configparser.ConfigParser):
+    SEARCH_PATHS = (
+        './xmet.conf',
+        os.environ['HOME'] + '/.xmet.conf',
+        '/etc/xmet/xmet.conf',
+    )
+
+    @staticmethod
+    def find() -> str:
+        for path in Config.SEARCH_PATHS:
+            if os.path.isfile(path):
+                return path
+
+    @staticmethod
+    def load(path: Optional[str]=None) -> Self:
+        if path is None:
+            path = Config.find()
+
+        if path is None:
+            raise ConfigFileException("Could not locate xmet configuration file")
+
+        config = Config()
+        config.read(path)
+
+        return config

lib/xmet/db.py

@@ -1,6 +1,10 @@
 import enum
 import sqlite3
 
+from typing import Self
+
+from xmet.config import Config
+
 class DatabaseOrder(enum.Enum):
     DEFAULT = 0
     ASC     = 1
@@ -112,6 +116,10 @@ class Database():
 
         return Database(db)
 
+    @staticmethod
+    def from_config(config: Config) -> Self:
+        return Database.connect(config['database']['path'])
+
     def column_placeholders(self, table, obj) -> list:
         ret = list()