Source code for seiscat.db

# -*- coding: utf8 -*-
# SPDX-License-Identifier: GPL-3.0-or-later
"""
Database functions for seiscat.

:copyright:
    2022-2023 Claudio Satriano <satriano@ipgp.fr>
:license:
    GNU General Public License v3.0 or later
    (https://www.gnu.org/licenses/gpl-3.0-standalone.html)
"""
import os
import sqlite3
import numpy as np
from obspy import UTCDateTime
from .utils import err_exit

# Current supported DB version
# Increment this number when changing the DB schema
DB_VERSION = 1


def _check_db_version(cursor, config):
    """
    Check if database version is compatible with current version.

    :param cursor: database cursor
    :param config: config object
    """
    db_version = cursor.execute('PRAGMA user_version').fetchone()[0]
    db_file = config['db_file']
    if db_version < DB_VERSION:
        msg = (
            f'"{db_file}" has an old database version: '
            f'"{db_version}" Current supported version is "{DB_VERSION}".\n'
            'Remove or rename your old database file, '
            'so that a new one can be created.'
        )
        err_exit(msg)


def _set_db_version(cursor):
    """
    Set the database version.

    :param cursor: database cursor
    """
    cursor.execute('PRAGMA user_version = {v:d}'.format(v=DB_VERSION))


[docs]def check_db_exists(config, initdb): """ Check if database file exists. :param config: config object :param initdb: if True, create new database file """ db_file = config.get('db_file', None) if db_file is None: err_exit('db_file not set in config file') if initdb and os.path.exists(db_file): ans = input( f'"{db_file}" already exists. ' 'Do you want to overwrite it?\n' f'(Current database will be saved as "{db_file}.bak") [y/N] ' ) if ans not in ['y', 'Y']: err_exit('No database file created. Exiting.') else: os.rename( db_file, f'{db_file}.bak') print( f'Backup of "{db_file}" saved to ' f'"{db_file}.bak"') if not initdb and not os.path.exists(db_file): err_exit( f'Database file "{db_file}" does not exist.\n' 'Run "seiscat initdb" first.' )
def _same_values(event1, event2): """ Check if two events have the same values. :param event1: first event :param event2: second event :returns: True if events have the same values, False otherwise """ for idx in range(2, len(event1)): try: # Use np.isclose() for numbers match = np.isclose(event1[idx], event2[idx]) except TypeError: # Use == for strings match = event1[idx] == event2[idx] if not match: return False return True def _get_evid(resource_id): """ Get evid from resource_id. :param resource_id: resource_id string :returns: evid string """ evid = resource_id if '/' in evid: evid = resource_id.split('/')[-1] if '?' in evid: evid = resource_id.split('?')[-1] if '&' in evid: evid = evid.split('&')[0] if '=' in evid: evid = evid.split('=')[-1] return evid def _get_db_field_definitions(config): """ Get a list of database fields. :param config: config object :returns: list of fields """ fields = [ 'evid TEXT', 'ver INTEGER', 'time TEXT', 'lat REAL', 'lon REAL', 'depth REAL', 'mag REAL', 'mag_type TEXT', 'event_type TEXT', ] extra_field_names = config['extra_field_names'] or [] extra_field_types = config['extra_field_types'] or [] fields.extend( f'{name} {dbtype}' for name, dbtype in zip(extra_field_names, extra_field_types)) return fields def _get_db_values_from_event(ev, config): """ Get a list of values from an obspy event object. :param ev: obspy event object :param config: config object :returns: list of values """ evid = _get_evid(str(ev.resource_id.id)) version = 1 orig = ev.preferred_origin() or ev.origins[0] time = str(orig.time) lat = orig.latitude lon = orig.longitude depth = orig.depth / 1e3 # km magntiude = ev.preferred_magnitude() or ev.magnitudes[0] mag = magntiude.mag mag_type = magntiude.magnitude_type event_type = ev.event_type values = [ evid, version, time, lat, lon, depth, mag, mag_type, event_type] # add extra fields extra_field_defaults = config['extra_field_defaults'] or [] values += extra_field_defaults return values
[docs]def write_catalog_to_db(cat, config, initdb): """ Write catalog to database. :param cat: obspy Catalog object :param config: config object :param initdb: if True, create new database file """ # open database connection conn = sqlite3.connect(config['db_file']) c = conn.cursor() if initdb: _set_db_version(c) else: _check_db_version(c, config) field_definitions = _get_db_field_definitions(config) # create table if it doesn't exist, use evid and ver as primary key c.execute( 'CREATE TABLE IF NOT EXISTS events ' f'({", ".join(field_definitions)}, PRIMARY KEY (evid, ver))') events_written = 0 for ev in cat: values = _get_db_values_from_event(ev, config) if initdb or config['overwrite_updated_events']: # add events to table, replace events that already exist c.execute( 'INSERT OR REPLACE INTO events VALUES ' f'({", ".join("?" * len(values))})', values) else: # check if an event with the same values already exists evid = values[0] c.execute( 'SELECT * FROM events WHERE evid = ?', (evid,)) rows = c.fetchall() rows_with_different_values = [ row for row in rows if not _same_values(values, row)] try: max_version = max(row[1] for row in rows_with_different_values) except ValueError: # rows_with_different_values is empty max_version = 0 values[1] = max_version + 1 # add events to table, ignore events that have same evid and vers # (i.e., the same primary keys) c.execute( 'INSERT OR IGNORE INTO events VALUES ' f'({", ".join("?" * len(values))})', values) events_written += c.rowcount # close database connection conn.commit() print(f'Wrote {events_written} events to database "{config["db_file"]}"')
[docs]def read_fields_and_rows_from_db(config): """ Read fields and rows from database. Return a list of fields and a list of rows. :param config: config object :returns: list of fields, list of rows """ db_file = config.get('db_file', None) if db_file is None: err_exit('db_file not set in config file') try: open(db_file, 'r') except FileNotFoundError: err_exit(f'Database file "{db_file}" not found.') conn = sqlite3.connect(db_file) c = conn.cursor() # read field names c.execute('PRAGMA table_info(events)') # we just need the field names, which are in the second column fields = [f[1] for f in c.fetchall()] # read events c.execute('SELECT * FROM events') rows = c.fetchall() allversions = config['args'].allversions if not allversions: # keep only the latest version of each event evids = set() rows_to_keep = [] for row in sorted(rows, key=lambda r: r[:2], reverse=True): evid = row[0] if evid not in evids: rows_to_keep.append(row) evids.add(evid) rows = rows_to_keep conn.close() return fields, rows
[docs]def read_events_from_db(config): """ Read events from database. Return a list of events. :param config: config object :returns: list of events, each event is a dictionary """ fields, rows = read_fields_and_rows_from_db(config) # create a list of dictionaries events_list = [] for event in rows: event_dict = dict(zip(fields, event)) event_dict['time'] = UTCDateTime(event_dict['time']) events_list.append(event_dict) return events_list
[docs]def get_catalog_stats(config): """ Get a string with catalog statistics. :param config: config object :returns: string with catalog statistics """ events = read_events_from_db(config) nevents = len(events) tmin = min(event['time'] for event in events) tmax = max(event['time'] for event in events) tmin = tmin.strftime('%Y-%m-%dT%H:%M:%S') tmax = tmax.strftime('%Y-%m-%dT%H:%M:%S') mag_min = min(event['mag'] for event in events) mag_max = max(event['mag'] for event in events) return ( f'{nevents} events from {tmin} to {tmax}\n' f'Magnitude range: {mag_min:.1f} - {mag_max:.1f}' )