Walk through the filesystem, store in sqlite db

spider.py

"""Walk through the filesystem, store in sqlite db

Utility script for walking a filesystem, and storing file information in a sqlite
database.

Goals/Design Notes:
 - [x] Pure standard library
 - [x] Name, Path as seprate columns
 - [x] Store the datetime that a file pth was inserted
 - [x] Implement fulltext search of both filenames and paths
    - Use `sqlite-utils` enable-fts as a reference (or use code directly?)
    - Answer - Wound up mostly relying on sqlite3 docs
 - [x] Add stats for how many files scanned in how long
 - [ ] Strech goal: figure out how to hash metadata and see what's changed


Example of querying the FTS table:
    -- Search both directory and filename
    SELECT * FROM fileinfo_fts WHERE fileinfo_fts MATCH 'needle' ORDER BY rank LIMIT 10;
    -- Search just filename
    SELECT * FROM fileinfo_fts WHERE filename MATCH 'needle' ORDER BY rank LIMIT 10;


MIT License

Copyright © 2024 Joe Kerhin

Permission is hereby granted, free of charge, to any person obtaining a copy of this
software and associated documentation files (the “Software”), to deal in the Software
without restriction, including without limitation the rights to use, copy, modify,
merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be included in all copies or
substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
THE USE OR OTHER DEALINGS IN THE SOFTWARE.

"""

import sqlite3
import os
import json
from datetime import datetime
from typing import Iterable

DB_FILE = "fileinfo.sqlite3"
# In normal use, this would be a bunch of network mounts
TO_SEARCH = [
    "\\\\some\\fileshare\\location",
]


def stat_to_dict(s_obj: os.stat_result) -> dict[str, int]:
    return {k: getattr(s_obj, k) for k in dir(s_obj) if k.startswith("st_")}


def db_connect(db_name: str = DB_FILE) -> sqlite3.Connection:
    con = sqlite3.connect(db_name)
    cur = con.cursor()
    cur.execute(
        """CREATE TABLE IF NOT EXISTS fileinfo(
            processed_timestamp TEXT,
            directory TEXT,
            filename TEXT,
            stats JSON,
            error TEXT
        )
        """
    )
    con.commit()
    return con


def populate_fts(con: sqlite3.Connection):
    con.execute(
        """CREATE VIRTUAL TABLE IF NOT EXISTS fileinfo_fts USING FTS5(
            directory, filename, content=fileinfo
        )
        """
    )
    con.commit()
    # NB: "Rows are assigned contiguously ascending rowid values, starting with 1, in
    #   the order that they are returned by the SELECT statement."
    con.execute(
        """INSERT INTO fileinfo_fts (rowid, directory, filename)
        SELECT rowid, directory, filename FROM fileinfo"""
    )
    con.commit()


def walk_dirs(con: sqlite3.Connection, to_crawl: Iterable[str]):
    for root_dir in to_crawl:
        for dirname, _, files in os.walk(root_dir):
            for filename in files:
                pth = os.path.join(dirname, filename)
                error_str, stats = None, None
                try:
                    stat_dict = stat_to_dict(os.stat(pth))
                    stats = json.dumps(stat_dict, indent=None)
                except KeyboardInterrupt as e:
                    # Don't catch keyboard interrupt, throw back up the stack
                    raise e
                except Exception as e:
                    error_str = str(e)
                proc_ts = datetime.now().isoformat()
                con.execute(
                    "INSERT INTO fileinfo VALUES(?, ?, ?, ?, ?)",
                    (proc_ts, dirname, filename, stats, error_str),
                )
                con.commit()


def main():
    con = db_connect(DB_FILE)

    start_scan = datetime.now()
    try:
        walk_dirs(con, TO_SEARCH)
    except KeyboardInterrupt:
        print("Exiting without completing scan...")

    end_scan = datetime.now()
    scan_dur = end_scan - start_scan

    (n_files,) = con.execute(
        "SELECT count(*) FROM fileinfo WHERE processed_timestamp >= ?",
        (start_scan.isoformat(),),
    ).fetchone()
    populate_fts(con)
    print(f"Scanned {n_files} in {scan_dur}")


if __name__ == "__main__":
    main()