Inconsistent path usage hinders immutability in config directory mode

[zner0L]

Problem description

I tried run datasette in immutable and directory mode at the same time. The documentation on this is a little ambiguous, but I figured out that if my configuration directory contains a inspect-data.json, generated by datasette inspect my-immutable.db --inspect-file=inspect-data.json, my-immutable would be loaded in immutable mode.
However, datasette would always load the database in mutable mode.

Problem resolution

After digging through the code, I found the problem. datasette checks which databases to load immutably by comparing just the filename and not the full path:

datasette/datasette/app.py

Lines 287 to 291 in 832f76c

	if not immutables:
	immutable_filenames = [i["file"] for i in inspect_data.values()]
	immutables = [
	f for f in self.files if Path(f).name in immutable_filenames
	]

But my inspect-data.json contained absolute paths, because I had run datasette inspect /not/my/cwd/*.db --inspect-file=/not/my/cwd/inspect-data.json with absolute paths.

Because the paths are used inconsistently without this being mentioned in the documentation, I couldn’t figure out why the database was loaded mutably. After I changed the path to just the filename, the problem disappeared.

My specific configs can be found at https://github.com/tweaselORG/data.tweasel.org/tree/main/datasette.

/-/versions:

{
    "python": {
        "version": "3.10.12",
        "full": "3.10.12 (main, Sep 11 2024, 15:47:36) [GCC 11.4.0]"
    },
    "datasette": {
        "version": "0.64.8"
    },
    "asgi": "3.0",
    "uvicorn": "0.30.1",
    "sqlite": {
        "version": "3.37.2",
        "fts_versions": [
            "FTS5",
            "FTS4",
            "FTS3"
        ],
        "extensions": {
            "json1": null
        },
        "compile_options": [
            "ATOMIC_INTRINSICS=1",
            "COMPILER=gcc-11.4.0",
            "DEFAULT_AUTOVACUUM",
            "DEFAULT_CACHE_SIZE=-2000",
            "DEFAULT_FILE_FORMAT=4",
            "DEFAULT_JOURNAL_SIZE_LIMIT=-1",
            "DEFAULT_MMAP_SIZE=0",
            "DEFAULT_PAGE_SIZE=4096",
            "DEFAULT_PCACHE_INITSZ=20",
            "DEFAULT_RECURSIVE_TRIGGERS",
            "DEFAULT_SECTOR_SIZE=4096",
            "DEFAULT_SYNCHRONOUS=2",
            "DEFAULT_WAL_AUTOCHECKPOINT=1000",
            "DEFAULT_WAL_SYNCHRONOUS=2",
            "DEFAULT_WORKER_THREADS=0",
            "ENABLE_COLUMN_METADATA",
            "ENABLE_DBSTAT_VTAB",
            "ENABLE_FTS3",
            "ENABLE_FTS3_PARENTHESIS",
            "ENABLE_FTS3_TOKENIZER",
            "ENABLE_FTS4",
            "ENABLE_FTS5",
            "ENABLE_JSON1",
            "ENABLE_LOAD_EXTENSION",
            "ENABLE_MATH_FUNCTIONS",
            "ENABLE_PREUPDATE_HOOK",
            "ENABLE_RTREE",
            "ENABLE_SESSION",
            "ENABLE_STMTVTAB",
            "ENABLE_UNLOCK_NOTIFY",
            "ENABLE_UPDATE_DELETE_LIMIT",
            "HAVE_ISNAN",
            "LIKE_DOESNT_MATCH_BLOBS",
            "MALLOC_SOFT_LIMIT=1024",
            "MAX_ATTACHED=10",
            "MAX_COLUMN=2000",
            "MAX_COMPOUND_SELECT=500",
            "MAX_DEFAULT_PAGE_SIZE=32768",
            "MAX_EXPR_DEPTH=1000",
            "MAX_FUNCTION_ARG=127",
            "MAX_LENGTH=1000000000",
            "MAX_LIKE_PATTERN_LENGTH=50000",
            "MAX_MMAP_SIZE=0x7fff0000",
            "MAX_PAGE_COUNT=1073741823",
            "MAX_PAGE_SIZE=65536",
            "MAX_SCHEMA_RETRY=25",
            "MAX_SQL_LENGTH=1000000000",
            "MAX_TRIGGER_DEPTH=1000",
            "MAX_VARIABLE_NUMBER=250000",
            "MAX_VDBE_OP=250000000",
            "MAX_WORKER_THREADS=8",
            "MUTEX_PTHREADS",
            "OMIT_LOOKASIDE",
            "SECURE_DELETE",
            "SOUNDEX",
            "SYSTEM_MALLOC",
            "TEMP_STORE=1",
            "THREADSAFE=1",
            "USE_URI"
        ]
    }
}