strukto-ai--mirage/examples/python/ram/ram_fuse_readonly.py

# ========= Copyright 2026 @ Strukto.AI All Rights Reserved. =========
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ========= Copyright 2026 @ Strukto.AI All Rights Reserved. =========

import os
import time
from pathlib import Path

from mirage import Mount, MountMode, Workspace
from mirage.resource.ram import RAMResource

REPO_ROOT = Path(__file__).resolve().parents[3]
DATA_DIR = REPO_ROOT / "data"

resource = RAMResource()
store = resource._store

for fpath in sorted(DATA_DIR.iterdir()):
    if fpath.is_file():
        key = "/" + fpath.name
        store.files[key] = fpath.read_bytes()
        store.dirs.add("/")

print(f"Seeded {len(store.files)} files from {DATA_DIR}")

with Workspace({"/data/": Mount(resource, fuse=True)},
               mode=MountMode.READ) as ws:
    time.sleep(1)
    mp = ws.fuse_mountpoint

    print(f"\n=== FUSE MODE (READ): mounted at {mp} ===\n")

    data_path = mp
    entries = sorted(os.listdir(data_path))
    for e in entries:
        size = os.path.getsize(f"{data_path}/{e}")
        print(f"  {e:30s} {size:>10,} bytes")

    existing = entries[0] if entries else "example.json"
    print(f"\n>>> FUSE mounted READ-ONLY at: {mp}")
    print(">>> In another terminal: reads ok, writes fail (EACCES).")
    print(f">>>   cat {data_path}/{existing}             # ok")
    print(f">>>   echo hi > {data_path}/new.txt         # EACCES (create)")
    print(
        f">>>   echo hi > {data_path}/{existing}        # EACCES (overwrite)")
    print(">>> Press Enter to unmount and exit...")
    input()

    records = ws.ops.records
    total = sum(r.bytes for r in records)
    print(f"\nStats: {len(records)} ops, {total} bytes transferred")