new additional pyfilesystem implementation 'uftpmount' which mounts t…

…he remote and accesses it via the local OSFS

CHANGES.md

@@ -7,6 +7,8 @@ Version 1.1.0 (mmm dd, 2024)
 ----------------------------
  - API CHANGE: new Storage.put_file() method accepting
  str-like or file-like data to upload to a remote destination
+ - new feature: new pyfilesystem implementation "uftpmount" which mounts
+ the remote directory and then accesses it via the local FS (OSFS)
 
 Version 1.0.1 (Mar 22, 2024)
 ----------------------------

pyunicore/uftp/uftpfs.py

@@ -16,7 +16,7 @@ class UFTPFS(FTPFS):
     Example: create with auth URL and username/password credentials
 
       from pyunicore.credentials import UsernamePassword
-      from pyunicore.uftpfs import UFTPFS
+      from pyunicore.uftp.uftpfs import UFTPFS
 
       auth = "https://localhost:9000/rest/auth/TEST
       creds = UsernamePassword("demouser", "test123")

pyunicore/uftp/uftpmountfs.py

@@ -0,0 +1,131 @@
+from os import getenv
+
+from fs.osfs import OSFS
+from fs.opener import Opener
+
+import pyunicore.credentials as uc_credentials
+from pyunicore.uftp.uftp import UFTP
+
+import subprocess
+
+
+class UFTPMOUNTFS(OSFS):
+    """A UFTP (UNICORE FTP) Filesystem which tries to mount the remote file system
+    and then access it locally.
+
+    This extends the fs.osfs.OSFS filesystem
+    with UFTP authentication.
+
+    Example: create with auth URL and username/password credentials
+
+      from pyunicore.credentials import UsernamePassword
+      from pyunicore.uftp.uftpmountfs import UFTPMOUNTFS
+
+      auth = "https://localhost:9000/rest/auth/TEST"
+      creds = UsernamePassword("demouser", "test123")
+      base_path = "/"
+      mount_dir = "/data/mount"
+
+      uftp_mount_fs = UFTPMOUNTFS(auth, creds, base_path, mount_dir)
+      uftp_mount_fs.tree()
+
+    Example: create with URL
+
+      from fs import open_fs
+      fs_url = "uftpmount://demouser:test123@localhost:9000/rest/auth/TEST:/opt/shared-data==/mnt"
+      uftp_fs = open_fs(fs_url)
+      uftp_fs.tree()
+    """
+
+    def __init__(self, auth_url, creds, base_path="/", mount_dir="./uftp_mount"):
+        """Creates a new UFTP FS instance authenticating using the given URL and credentials"""
+        self.host, self.port, uftp_password = UFTP().authenticate(creds, auth_url, base_path)
+        self.base_path = base_path
+        self.mount_dir = mount_dir
+        self._ensure_unmount(mount_dir)
+        print(self._run_fusedriver(self.host, self.port, uftp_password, self.mount_dir))
+        super().__init__(mount_dir)
+
+    def _ensure_unmount(self, mount_point):
+        """
+        Unmounts the requested directory
+        """
+        cmd = "fusermount -u '%s'" % mount_point
+        return self._run_command(cmd)
+
+    def _run_fusedriver(self, host, port, pwd, mount_point, debug=False):
+        cmds = [
+            "export UFTP_PASSWORD=%s" % pwd,
+            f"python3 -m pyunicore.uftp.uftpfuse {host}:{port} '{mount_point}'",
+        ]
+        cmd = ""
+        for c in cmds:
+            cmd += c + "\n"
+        return self._run_command(cmd)
+
+    def _run_command(self, cmd):
+        try:
+            raw_output = subprocess.check_output(
+                cmd, shell=True, bufsize=4096, stderr=subprocess.STDOUT
+            )
+            exit_code = 0
+        except subprocess.CalledProcessError as cpe:
+            raw_output = cpe.output
+            exit_code = cpe.returncode
+        return exit_code, raw_output.decode("UTF-8")
+
+    def hassyspath(self, path):
+        return False
+
+    def __repr__(self):
+        return (
+            f"UFTPMOUNTFS({self.host!r}, port={self.port!r})"
+            ", base_path={self.base_path!r}, mount_dir={self.mount_dir!r}"
+        )
+
+    __str__ = __repr__
+
+
+class UFTPMountOpener(Opener):
+    """Defines the Opener class used to open UFTP Mount FS instances based on a URL"""
+
+    protocols = ["uftpmount"]
+
+    def _parse(self, resource_url):
+        tok = resource_url.split("/rest/")
+        auth_url = "https://" + tok[0]
+        tok2 = tok[1].split(":")
+        auth_url = auth_url + "/rest/" + tok2[0]
+        base_dir = tok2[1] if len(tok) > 1 else "/"
+        tok3 = base_dir.split("==")
+        base_dir = tok3[0]
+        mount_dir = tok3[1] if len(tok3) > 1 else "/uftp_mount"
+        return auth_url, base_dir, mount_dir
+
+    def _read_token(self, token_spec):
+        token = None
+        if token_spec:
+            if token_spec.startswith("@@"):
+                env_name = token_spec[2:]
+                token = getenv(env_name, None)
+            elif token_spec.startswith("@"):
+                file_name = token_spec[1:]
+                with open(file_name) as f:
+                    token = f.read().strip()
+            else:
+                token = token_spec
+        return token
+
+    def _create_credential(self, parse_result):
+        token = self._read_token(parse_result.params.get("token", None))
+        return uc_credentials.create_credential(
+            username=parse_result.username,
+            password=parse_result.password,
+            token=token,
+            identity=parse_result.params.get("identity", None),
+        )
+
+    def open_fs(self, fs_url, parse_result, writeable, create, cwd):
+        auth_url, base_dir, mount_dir = self._parse(parse_result.resource)
+        cred = self._create_credential(parse_result)
+        return UFTPMOUNTFS(auth_url, cred, base_dir, mount_dir)

setup.py

@@ -38,6 +38,7 @@
     entry_points={
         "fs.opener": [
             "uftp = pyunicore.uftp.uftpfs:UFTPOpener",
+            "uftpmount = pyunicore.uftp.uftpmountfs:UFTPMountOpener",
         ],
         "console_scripts": [
             "unicore-port-forwarder=pyunicore.forwarder:main",