Major upgrades, much code and docs rewritten.

README.md

@@ -1,12 +1,10 @@
 # Web File Storage
 
-Development install:
+Run directly from repository with Hatch (or use pip install as usual):
-
 ```sh
-pip install hatch --break-system-packages
+hatch run sanic cista --reload --dev
-hatch run sanic cista --reload --dev       # Runs on localhost:8000
 ```
 
-Environment variable `STORAGE=<path>` may be used to choose which folder it serves. The default is current directory.
+Configuration file is created `.cista.toml` in current directory, which is also shared by default. Edit while the server is not running to set share path and other parameters.
 
-No authentication is supported, so implement access control externally or be careful with your files.
+No authentication yet, so implement access control externally or be careful with your files.

cista/app.py

@@ -1,13 +1,10 @@
 import asyncio
 from importlib.resources import files
-from pathlib import Path
 
 import msgspec
 from sanic import Sanic
 from sanic.log import logger
 from sanic.response import html
-from watchdog.events import FileSystemEventHandler
-from watchdog.observers import Observer
 
 from . import watching
 from .fileio import ROOT, FileServer
@@ -15,6 +12,7 @@ from .protocol import ErrorMsg, FileRange, StatusMsg
 
 app = Sanic("cista")
 fileserver = FileServer()
+watching.register(app, "/api/watch")
 
 def asend(ws, msg):
     return ws.send(msg if isinstance(msg, bytes) else msgspec.json.encode(msg).decode())
@@ -27,22 +25,6 @@ async def start_fileserver(app, _):
 async def stop_fileserver(app, _):
     await fileserver.stop()
 
-@app.before_server_start
-async def start_watcher(app, _):
-    class Handler(FileSystemEventHandler):
-        def on_any_event(self, event):
-            watching.update(Path(event.src_path).relative_to(ROOT))
-    app.ctx.observer = Observer()
-    app.ctx.observer.schedule(Handler(), str(ROOT), recursive=True)
-    app.ctx.observer.start()
-
-@app.after_server_stop
-async def stop_watcher(app, _):
-    app.ctx.observer.stop()
-    app.ctx.observer.join()
-
-
-
 @app.get("/")
 async def index_page(request):
     index = files("cista").joinpath("static", "index.html").read_text()
@@ -50,16 +32,6 @@ async def index_page(request):
 
 app.static("/files", ROOT, use_content_range=True, stream_large_files=True, directory_view=True)
 
-@app.websocket('/api/watch')
-async def watch(request, ws):
-    try:
-        q = watching.pubsub[ws] = asyncio.Queue()
-        await asend(ws, {"root": watching.tree})
-        while True:
-            await asend(ws, await q.get())
-    finally:
-        del watching.pubsub[ws]
-
 @app.websocket('/api/upload')
 async def upload(request, ws):
     alink = fileserver.alink
@@ -78,24 +50,28 @@ async def upload(request, ws):
                 d = f"{len(data)} bytes" if isinstance(data, bytes) else data
                 raise ValueError(f"Expected {req.end - pos} more bytes, got {d}")
             # Report success
-            res = StatusMsg(status="upload", url=url, req=req)
+            res = StatusMsg(status="ack", req=req)
             await asend(ws, res)
-            print(res)
+            await ws.drain()
-
         except Exception as e:
-            res = ErrorMsg(error=str(e), url=url, req=req)
+            res = ErrorMsg(error=str(e), req=req)
             await asend(ws, res)
             logger.exception(repr(res), e)
             return
 
+@app.websocket("/ws")
+async def ws(request, ws):
+    while True:
+        data = await ws.recv()
+        await ws.send(data)
 
 @app.websocket('/api/download')
 async def download(request, ws):
     alink = fileserver.alink
-    url = request.url_for("download")
     while True:
         req = None
         try:
+            print("Waiting for download command")
             text = await ws.recv()
             if not isinstance(text, str):
                 raise ValueError(f"Expected JSON control, got binary len(data) = {len(text)}")
@@ -108,12 +84,14 @@ async def download(request, ws):
                 await asend(ws, data)
                 pos += len(data)
             # Report success
-            res = StatusMsg(status="download", url=url, req=req)
+            res = StatusMsg(status="ack", req=req)
             await asend(ws, res)
+            print(ws, dir(ws))
+            await ws.drain()
             print(res)
 
         except Exception as e:
-            res = ErrorMsg(error=str(e), url=url, req=req)
+            res = ErrorMsg(error=str(e), req=req)
             await asend(ws, res)
             logger.exception(repr(res), e)
             return

cista/config.py

@@ -0,0 +1,156 @@
+from __future__ import annotations
+
+import hmac
+import re
+import secrets
+from functools import wraps
+from hashlib import sha256
+from pathlib import Path, PurePath
+from time import time
+from unicodedata import normalize
+
+import argon2
+import msgspec
+
+_argon = argon2.PasswordHasher()
+_droppyhash = re.compile(r'^([a-f0-9]{64})\$([a-f0-9]{8})$')
+
+class Config(msgspec.Struct):
+    path: Path = Path.cwd()
+    secret: str = secrets.token_hex(12)
+    public: bool = False
+    users: dict[str, User] = {}
+    sessions: dict[str, Session] = {}
+    links: dict[str, Link] = {}
+
+class User(msgspec.Struct, omit_defaults=True):
+    privileged: bool = False
+    hash: str = ""
+    lastSeen: int = 0
+
+    def set_password(self, password: str):
+        self.hash = _argon.hash(_pwnorm(password))
+
+class Session(msgspec.Struct):
+    username: str
+    lastSeen: int
+
+class Link(msgspec.Struct, omit_defaults=True):
+    location: str
+    creator: str = ""
+    expires: int = 0
+
+config = Config()
+
+def derived_secret(*params, len=8) -> bytes:
+    """Used to derive secret keys from the main secret"""
+    # Each part is made the same length by hashing first
+    combined = b"".join(
+        sha256(
+            p if isinstance(p, bytes) else f"{p}".encode()
+        ).digest()
+        for p in [config.secret, *params]
+    )
+    # Output a bytes of the desired length
+    return sha256(combined).digest()[:len]
+
+def _pwnorm(password):
+    return normalize('NFC', password).strip().encode()
+
+def login(username: str, password: str):
+    un = _pwnorm(username)
+    pw = _pwnorm(password)
+    try:
+        u = config.users[un.decode()]
+    except KeyError:
+        raise ValueError("Invalid username")
+    # Verify password
+    if not u.hash:
+        raise ValueError("Account disabled")
+    if (m := _droppyhash.match(u.hash)) is not None:
+        h, s = m.groups()
+        h2 = hmac.digest(pw + s.encode() + un, b"", "sha256").hex()
+        if not hmac.compare_digest(h, h2):
+            raise ValueError("Invalid password")
+        # Droppy hashes are weak, do a hash update
+        u.set_password(password)
+    else:
+        try:
+            _argon.verify(u.hash, pw)
+        except Exception:
+            raise ValueError("Invalid password")
+        if _argon.check_needs_rehash(u.hash):
+            u.set_password(password)
+    # Login successful
+    now = int(time())
+    u.lastSeen = now
+    sid = secrets.token_urlsafe(12)
+    config.sessions[sid] = Session(username, now)
+    return u, sid
+
+def enc_hook(obj):
+    if isinstance(obj, PurePath):
+        return obj.as_posix()
+    raise TypeError
+
+def dec_hook(typ, obj):
+    if typ is Path:
+        return Path(obj)
+    raise TypeError
+
+conffile = Path.cwd() / ".cista.toml"
+
+def config_update(modify):
+    global config
+    tmpname = conffile.with_suffix(".tmp")
+    try:
+        f = tmpname.open("xb")
+    except FileExistsError:
+        if tmpname.stat().st_mtime < time() - 1:
+            tmpname.unlink()
+        return "collision"
+    try:
+        # Load, modify and save with atomic replace
+        try:
+            old = conffile.read_bytes()
+            c = msgspec.toml.decode(old, type=Config, dec_hook=dec_hook)
+        except FileNotFoundError:
+            old = b""
+            c = Config()  # Initialize with defaults
+        c = modify(c)
+        new = msgspec.toml.encode(c, enc_hook=enc_hook)
+        if old == new:
+            f.close()
+            tmpname.unlink()
+            config = c
+            return "read"
+        f.write(new)
+        f.close()
+        tmpname.rename(conffile)  # Atomic replace
+    except:
+        f.close()
+        tmpname.unlink()
+        raise
+    config = c
+    return "modified" if old else "created"
+
+def modifies_config(modify):
+    """Decorator for functions that modify the config file"""
+    @wraps(modify)
+    def wrapper(*args, **kwargs):
+        m = lambda c: modify(c, *args, **kwargs)
+        # Retry modification in case of write collision
+        while (c := config_update(m)) == "collision":
+            time.sleep(0.01)
+        return c
+    return wrapper
+
+@modifies_config
+def droppy_import(config: Config) -> Config:
+    p = Path.home() / ".droppy/config"
+    cf = msgspec.json.decode((p / "config.json").read_bytes())
+    db = msgspec.json.decode((p / "db.json").read_bytes())
+    return msgspec.convert(cf | db, Config)
+
+# Load/initialize config file
+print(conffile, config_update(lambda c: c))

cista/fileio.py

@@ -1,20 +1,28 @@
 import asyncio
 import os
 import unicodedata
-from pathlib import Path
+from pathlib import Path, PurePosixPath
 
 from pathvalidate import sanitize_filepath
 
+from . import config
 from .asynclink import AsyncLink
 from .lrucache import LRUCache
 
-ROOT = Path(os.environ.get("STORAGE", Path.cwd()))
+ROOT = config.config.path
+print("Serving", ROOT)
 
-def sanitize_filename(filename):
+def fuid(stat) -> str:
+    """Unique file ID. Stays the same on renames and modification."""
+    return config.derived_secret("filekey-inode", stat.st_dev, stat.st_ino).hex()
+
+def sanitize_filename(filename: str) -> str:
     filename = unicodedata.normalize("NFC", filename)
+    # UNIX filenames can contain backslashes but for compatibility we replace them with dashes
+    filename = filename.replace("\\", "-")
     filename = sanitize_filepath(filename)
-    filename = filename.replace("/", "-")
+    filename = filename.strip("/")
-    return filename
+    return PurePosixPath(filename).as_posix()
 
 class File:
     def __init__(self, filename):

cista/protocol.py

@@ -15,11 +15,9 @@ class FileRange(msgspec.Struct):
 class ErrorMsg(msgspec.Struct):
     error: str
     req: FileRange
-    url: str
 
 class StatusMsg(msgspec.Struct):
     status: str
-    url: str
     req: FileRange
 
 
@@ -32,7 +30,38 @@ class FileEntry(msgspec.Struct):
 class DirEntry(msgspec.Struct):
     size: int
     mtime: int
-    dir: Dict[str, Union[FileEntry, DirEntry]]
+    dir: DirList
+
+    def __getitem__(self, name):
+        return self.dir[name]
+
+    def __setitem__(self, name, value):
+        self.dir[name] = value
+
+    def __contains__(self, name):
+        return name in self.dir
+
+    def __delitem__(self, name):
+        del self.dir[name]
+
+    @property
+    def props(self):
+        return {
+            k: v
+            for k, v in self.__struct_fields__
+            if k != "dir"
+        }
+
+DirList = dict[str, Union[FileEntry, DirEntry]]
+
+
+class UpdateEntry(msgspec.Struct, omit_defaults=True):
+    """Updates the named entry in the tree. Fields that are set replace old values. A list of entries recurses directories."""
+    name: str = ""
+    deleted: bool = False
+    size: int | None = None
+    mtime: int | None = None
+    dir: DirList | None = None
 
 def make_dir_data(root):
     if len(root) == 2:

cista/static/index.html

@@ -1,5 +1,26 @@
 <!DOCTYPE html>
 <title>Storage</title>
+<style>
+  body {
+    font-family: sans-serif;
+    max-width: 100ch;
+    margin: 0 auto;
+    padding: 1em;
+    background-color: #333;
+    color: #eee;
+  }
+  td {
+    text-align: right;
+    padding: .5em;
+  }
+  td:first-child {
+    text-align: left;
+  }
+  a {
+    color: inherit;
+    text-decoration: none;
+  }
+</style>
 <div>
   <h2>Quick file upload</h2>
   <p>Uses parallel WebSocket connections for increased bandwidth /api/upload</p>
@@ -8,84 +29,148 @@
 </div>
 
 <div>
-  <h2>File downloads (websocket)</h2>
+  <h2>Files</h2>
   <ul id=file_list></ul>
 </div>
 
-<h2>File listings</h2>
-<p>Plain HTML browser <a href=/files/>/files/</a></p>
-
-<p>JSON list updated via WebSocket /api/watch:</p>
-
-<textarea id=list style="padding: 1em; width: 80ch; height: 40ch;"></textarea>
 <script>
-const list = document.getElementById("list")
 let files = {}
+let flatfiles = {}
 
 function createWatchSocket() {
   const wsurl = new URL("/api/watch", location.href.replace(/^http/, 'ws'))
   const ws = new WebSocket(wsurl)
   ws.onmessage = event => {
     msg = JSON.parse(event.data)
-    console.log("Watch", msg)
+    if (msg.update) {
-    if (msg.root) {
+      tree_update(msg.update)
-      files = msg.root
       file_list(files)
-    } else if (msg.update) {
+    } else {
-      const {path, data} = msg.update
+      console.log("Unkonwn message from watch socket", msg)
-      for (const p of path.split("/")) {
-        // TODO update files at path with new data
     }
   }
-    list.value = JSON.stringify(files)
-  }
 }
 
-function file_list(files) {
-  const ul = document.getElementById("file_list")
-  ul.innerHTML = ""
-  const dir = ""
-  let ptr = files.dir
-  console.log(ptr)
-  for (const name of Object.keys(ptr)) {
-    if (ptr[name].dir) continue
-    const {size, mtime} = ptr[name]
-    const li = document.createElement("li")
-    const a = document.createElement("a")
-    ul.appendChild(li)
-    li.appendChild(a)
-    a.textContent = name
-    a.href = name
-    a.onclick = event => {
-      event.preventDefault()
-      download(name, size)
-    }
-  }
-
-}
 createWatchSocket()
 
-async function download(name, size) {
+function tree_update(msg) {
+  let node = files
+  for (const elem of msg) {
+    if (elem.deleted) {
+      delete node.dir[elem.name]
+      delete flatfiles[p]
+      break
+    }
+    if (elem.name !== undefined) node = node.dir[elem.name] ||= {}
+    if (elem.size !== undefined) node.size = elem.size
+    if (elem.mtime !== undefined) node.mtime = elem.mtime
+    if (elem.dir !== undefined) node.dir = elem.dir
+  }
+  // Update paths and flatfiles
+  files.path = "/"
+  const nodes = [files]
+  flatfiles = {}
+  while (node = nodes.pop()) {
+    flatfiles[node.path] = node
+    if (node.dir === undefined) continue
+    for (const name of Object.keys(node.dir)) {
+      const child = node.dir[name]
+      child.path = node.path + name + (child.dir === undefined ? "" : "/")
+      nodes.push(child)
+    }
+  }
+}
+
+var collator = new Intl.Collator(undefined, {numeric: true, sensitivity: 'base'});
+
+const compare_path = (a, b) => collator.compare(a.path, b.path)
+const compare_time = (a, b) => a.mtime > b.mtime
+
+function file_list(files) {
+  const table = document.getElementById("file_list")
+  const sorted = Object.values(flatfiles).sort(compare_time)
+  table.innerHTML = ""
+  for (const f of sorted) {
+    const {path, size, mtime} = f
+    const tr = document.createElement("tr")
+    const name_td = document.createElement("td")
+    const size_td = document.createElement("td")
+    const mtime_td = document.createElement("td")
+    const a = document.createElement("a")
+    table.appendChild(tr)
+    tr.appendChild(name_td)
+    tr.appendChild(size_td)
+    tr.appendChild(mtime_td)
+    name_td.appendChild(a)
+    size_td.textContent = size
+    mtime_td.textContent = formatUnixDate(mtime)
+    a.textContent = path
+    a.href = `/files${path}`
+    /*a.onclick = event => {
+      if (window.showSaveFilePicker) {
+        event.preventDefault()
+        download_ws(name, size)
+      }
+    }
+    a.download = ""*/
+  }
+}
+
+function formatUnixDate(t) {
+    const date = new Date(t * 1000)
+    const now = new Date()
+    const diff = date - now
+    const formatter = new Intl.RelativeTimeFormat('en', { numeric: 'auto' })
+
+    if (Math.abs(diff) <= 60000) {
+        return formatter.format(Math.round(diff / 1000), 'second')
+    }
+
+    if (Math.abs(diff) <= 3600000) {
+        return formatter.format(Math.round(diff / 60000), 'minute')
+    }
+
+    if (Math.abs(diff) <= 86400000) {
+        return formatter.format(Math.round(diff / 3600000), 'hour')
+    }
+
+    if (Math.abs(diff) <= 604800000) {
+        return formatter.format(Math.round(diff / 86400000), 'day')
+    }
+
+    return date.toLocaleDateString()
+}
+
+async function download_ws(name, size) {
+  const fh = await window.showSaveFilePicker({
+    suggestedName: name,
+  })
+  const writer = await fh.createWritable()
+  writer.truncate(size)
   const wsurl = new URL("/api/download", location.href.replace(/^http/, 'ws'))
   const ws = new WebSocket(wsurl)
-  ws.binaryType = 'arraybuffer'
+  let pos = 0
   ws.onopen = () => {
-    console.log("Download socket connected")
+    console.log("Downloading over WebSocket", name, size)
     ws.send(JSON.stringify({name, start: 0, end: size, size}))
   }
   ws.onmessage = event => {
-    const data = event.data
+    if (typeof event.data === 'string') {
-    console.log("Download", data)
+      const msg = JSON.parse(event.data)
-    const blob = new Blob([data], {type: "application/octet-stream"})
+      console.log("Download finished", msg)
-    const url = URL.createObjectURL(blob)
-    const a = document.createElement("a")
-    a.href = url
-    a.download = name
-    a.click()
       ws.close()
+      return
+    }
+    console.log("Received chunk", name, pos, pos + event.data.size)
+    pos += event.data.size
+    writer.write(event.data)
   }
   ws.onclose = () => {
-    console.log("Download socket disconnected")
+    if (pos < size) {
+      console.log("Download aborted", name, pos)
+      writer.truncate(pos)
+    }
+    writer.close()
   }
 }
 
@@ -95,7 +180,7 @@ const numConnections = 2
 const chunkSize = 1<<20
 const wsConnections = new Set()
 
-for (let i = 0; i < numConnections; i++) createUploadWS()
+//for (let i = 0; i < numConnections; i++) createUploadWS()
 
 function createUploadWS() {
   const wsurl = new URL("/api/upload", location.href.replace(/^http/, 'ws'))

cista/watching.py

@@ -1,19 +1,20 @@
+import asyncio
 import secrets
-from hashlib import sha256
 from pathlib import Path, PurePosixPath
+import threading
+from watchdog.events import FileSystemEventHandler
+from watchdog.observers import Observer
 
 import msgspec
 
+from . import config
 from .fileio import ROOT
-from .protocol import DirEntry, FileEntry
+from .protocol import DirEntry, FileEntry, UpdateEntry
 
 secret = secrets.token_bytes(8)
 pubsub = {}
 
-def fuid(stat):
+def walk(path: Path = ROOT) -> DirEntry | FileEntry | None:
-    return sha256((stat.st_dev << 32 | stat.st_ino).to_bytes(8, 'big') + secret).hexdigest()[:16]
-
-def walk(path: Path = ROOT):
     try:
         s = path.stat()
         mtime = int(s.st_mtime)
@@ -27,32 +28,99 @@ def walk(path: Path = ROOT):
         else:
             size = 0
         return DirEntry(size, mtime, tree)
+    except FileNotFoundError:
+        return None
     except OSError as e:
         print("OS error walking path", path, e)
         return None
 
-tree = walk()
+tree = {"": walk()}
+tree_lock = threading.Lock()
 
-def update(relpath: PurePosixPath):
+def refresh():
-    ptr = tree.dir
+    root = tree[""]
-    path = ROOT
+    return msgspec.json.encode({"update": [
-    name = ""
+        UpdateEntry(size=root.size, mtime=root.mtime, dir=root.dir)
-    for name in relpath.parts[:-1]:
+    ]}).decode()
-        path /= name
+
-        try:
+def update(relpath: PurePosixPath, loop):
-            ptr = ptr[name].dir
+    new = walk(ROOT / relpath)
-        except KeyError:
+    with tree_lock:
+        msg = update_internal(relpath, new)
+        print(msg)
+        asyncio.run_coroutine_threadsafe(broadcast(msg), loop)
+
+def update_internal(relpath: PurePosixPath, new: DirEntry | FileEntry | None):
+    path = "", *relpath.parts
+    old = tree
+    elems = []
+    for name in path:
+        if name not in old:
+            # File or folder created
+            old = None
+            elems.append((name, None))
+            if len(elems) < len(path):
+                raise ValueError("Tree out of sync")
             break
-    new = walk(path)
+        old = old[name]
-    old = ptr.pop(name, None)
+        elems.append((name, old))
-    if new is not None:
-        ptr[name] = new
     if old == new:
-        return
+        return  # No changes
-    print("Update", relpath)
+    mt = new.mtime if new else 0
-    # TODO: update parents size/mtime
+    szdiff = (new.size if new else 0) - (old.size if old else 0)
-    msg = msgspec.json.encode({"update": {
+    # Update parents
-        "path": relpath.as_posix(),
+    update = []
-        "data": new,
+    for name, entry in elems[:-1]:
-    }})
+        u = UpdateEntry(name)
-    for queue in pubsub.values(): queue.put_nowait(msg)
+        if szdiff:
+            entry.size += szdiff
+            u.size = entry.size
+        if mt > entry.mtime:
+            u.mtime = entry.mtime = mt
+        update.append(u)
+    # The last element is the one that changed
+    print([e[0] for e in elems])
+    name, entry = elems[-1]
+    parent = elems[-2][1] if len(elems) > 1 else tree
+    u = UpdateEntry(name)
+    if new:
+        parent[name] = new
+        if u.size != new.size: u.size = new.size
+        if u.mtime != new.mtime: u.mtime = new.mtime
+        if isinstance(new, DirEntry):
+            if u.dir == new.dir: u.dir = new.dir
+    else:
+        del parent[name]
+        u.deleted = True
+    update.append(u)
+    return msgspec.json.encode({"update": update}).decode()
+
+async def broadcast(msg):
+    for queue in pubsub.values():
+        await queue.put_nowait(msg)
+
+def register(app, url):
+    @app.before_server_start
+    async def start_watcher(app, loop):
+        class Handler(FileSystemEventHandler):
+            def on_any_event(self, event):
+                update(Path(event.src_path).relative_to(ROOT), loop)
+        app.ctx.observer = Observer()
+        app.ctx.observer.schedule(Handler(), str(ROOT), recursive=True)
+        app.ctx.observer.start()
+
+    @app.after_server_stop
+    async def stop_watcher(app, _):
+        app.ctx.observer.stop()
+        app.ctx.observer.join()
+
+    @app.websocket(url)
+    async def watch(request, ws):
+        try:
+            with tree_lock:
+                q = pubsub[ws] = asyncio.Queue()
+                await ws.send(refresh())
+            while True:
+                await ws.send(await q.get())
+        finally:
+            del pubsub[ws]

pyproject.toml

@@ -14,9 +14,11 @@ authors = [
 classifiers = [
 ]
 dependencies = [
+    "argon2-cffi",
     "msgspec",
     "pathvalidate",
     "sanic",
+    "tomli_w",
     "watchdog",
 ]