Logic improvements

More documentation

classes/chunk.py

@@ -5,7 +5,7 @@ class Chunk:
     """A class defining a single chunk of a file to be uploaded"""
 
     @staticmethod
-    def fromFile(fileobj, count: int, chunksize: int) -> type[Chunk]:
+    def fromFile(fileobj, count: int, chunksize: int):
         """Create a new Chunk object from a File
 
         Args:
@@ -15,9 +15,9 @@ class Chunk:
             chunksize (int): Size of each chunk in bytes
 
         Returns:
-            A Chunk object containing the portion of the File object beginning
-            at (count * chunksize) bytes and ending at ((count + 1) * chunksize
-            - 1) bytes
+            classes.chunk.Chunk: A Chunk object containing the portion of the 
+            File object beginning at (count * chunksize) bytes and ending at 
+            ((count + 1) * chunksize - 1) bytes
         """
         return fileobj.getChunk(count, chunksize)
 

classes/connection.py

@@ -143,7 +143,7 @@ class Connection:
                 return True
         return False
 
-    def pushChunk(self, chunk, path: Optional[str, Path] = None) -> None:
+    def pushChunk(self, chunk, path: Optional[Union[str, Path]] = None) -> None:
         """Push the content of a Chunk object to the Vessel
 
         Args:

classes/database.py

@@ -32,10 +32,14 @@ class Database:
         """
         cur = self.getCursor()
         cur.execute(query, parameters)
-        self.commit()  # Instantly commit after every write action
+        self.commit()  # Instantly commit after every (potential) write action
 
     def commit(self) -> None:
         """Commit the current database transaction
+
+        N.B.: Commit instantly after every write action to make the database
+        "thread-safe". Connections will time out if the database is locked for
+        more than five seconds.
         """
         self._con.commit()
 

classes/directory.py

@@ -4,14 +4,14 @@ import os
 import pathlib
 
 from configparser import SectionProxy
-from typing import Union
+from typing import Union, Optional
 
 
 class Directory:
     """Class representing a Directory on the local filesystem
     """
     @classmethod
-    def fromConfig(cls, config: SectionProxy) -> Directory:  # pylint: disable=undefined-variable
+    def fromConfig(cls, config: SectionProxy):
         """Create Directory object from a Directory section in the Config file
 
         Args:
@@ -54,7 +54,22 @@ class Directory:
         """Get all Files in Directory
 
         Returns:
-            list: List of names (str) of files within the Directory
+            list: List of File objects for files within the Directory
         """
         files = [f for f in os.listdir(self.location) if os.path.isfile]
         return [File(f, self) for f in files]
+
+    def getFile(self, name: str) -> Optional[File]:
+        """Get a file in the Directory by name
+
+        Args:
+            name (str): Filename of the File to get
+
+        Returns:
+            File, optional: File object if the file was found, else None
+        """
+
+        try:
+            return File(name, self)
+        except FileNotFoundError:
+            return None

classes/file.py

@@ -4,9 +4,13 @@ from classes.database import Database
 from typing import Optional
 
 import hashlib
+import os.path
 
 
 class File:
+    """Object representing a file found in a local Directory
+    """
+
     def __init__(self, name: str, directory, uuid: Optional[str] = None) -> None:
         """Initialize new File object
 
@@ -16,13 +20,25 @@ class File:
               is located within
             uuid (str, optional): Unique identifier of this File object. Will
               be retrieved from database if None. Defaults to None.
+
+        Raises:
+            FileNotFoundError: Raised if the specified File does not exist
         """
         self.name = name
         self.directory = directory
+
+        if not self.exists():
+            raise FileNotFoundError(f"File {self.name} does not exist in {self.directory}!")
+
         self.uuid = uuid or self.getUUID()
 
-    """Object representing a file found in a local Directory
-    """
+    def exists(self) -> bool:
+        """Check if the File exists on the local file system
+
+        Returns:
+            bool: True if the File exists, else False
+        """
+        return os.path.isfile(self.directory.location / self.name)
 
     def getUUID(self) -> str:
         """Return unique identifier for this File object

classes/remotefile.py

@@ -2,42 +2,98 @@ from const import STATUS_COMPLETE, STATUS_START
 
 
 class RemoteFile:
-    def __init__(self, fileobj, vessel, chunksize=1048576):
+    """Class describing the transfer status of a File to a Vessel
+    """
+
+    def __init__(self, fileobj, vessel, chunksize: int) -> None:
+        """Initialize a new RemoteFile object
+
+        Args:
+            fileobj (classes.file.File): File object to transfer to a Vessel
+            vessel (classes.vessel.Vessel): Vessel to transfer the File to
+            chunksize (int): Size of a single Chunk to transfer
+        """
         self.file = fileobj
         self.vessel = vessel
         self.chunksize = chunksize
 
-    def getStatus(self):
+    def getStatus(self) -> int:
+        """Get the current transfer status
+
+        Returns:
+            int: Number of the last Chunk that was uploaded, or STATUS_COMPLETE
+              (-1) if a file upload is complete and waiting for finalization,
+              or STATUS_START (-2) if no Chunk has been uploaded yet
+        """
+
+        # Get all files in the vessel's tempdir
+
         ls = self.vessel.connection._listdir(self.vessel.tempdir)
         files = [f for f in ls if f.startswith(
             self.file.uuid) and f.endswith(".part")]
 
-        ids = [-1]
+        # Find the file with the largest chunk number
+
+        count = -1
 
         for f in files:
             part = f.split("_")[1].split(".")[0]
-            if part == "complete":
-                if self.validateComplete():
-                    return STATUS_COMPLETE
-            ids.append(int(part))
+            if part == "complete":  # If a reassembled file is found
+                if self.validateComplete(True): # and it is not broken
+                    return STATUS_COMPLETE # the upload is complete
 
-        count = max(ids)
+            # Else save the chunk number if it is larger than the previous
+            count = max(count, int(part))
 
+        # Find and return the largest non-corrupt chunk
         while count >= 0:
             if self.validateChunk(count):
                 return count
             count -= 1
 
+        # If no (more) files exist, we are just getting started
         return STATUS_START
 
-    def validateChunk(self, count):
+    def validateChunk(self, count: int) -> bool:
+        """Validate that a Chunk was uploaded correctly
+
+        Args:
+            count (int): Chunk number to validate
+
+        Returns:
+            bool: True if file has been uploaded correctly, else False
+        """
         return self.vessel.connection.assertChunkComplete(self.getChunk(count))
 
-    def validateComplete(self):
-        return self.validateChunk(-1)
+    def validateComplete(self, allow_retry: bool = False):
+        """Validate that the complete File was reassembled correctly
 
-    def compileComplete(self):
+        Args:
+            allow_retry (bool, optional): If True, assume that compileComplete
+              failed for some other reason than corrupt Chunks, and only delete
+              compiled file, else clear entire temporary directory. Defaults to
+              False.
+
+        Returns:
+            bool: True if file was reassembled correctly, else False
+        """
+        return self.vessel.connection.assertComplete(self, allow_retry)
+
+    def compileComplete(self) -> None:
+        """Reassemble a complete File from the uploaded Chunks
+        """
         self.vessel.connection.compileComplete(self)
 
-    def getChunk(self, count):
+    def getChunk(self, count: int):
+        """Get a Chunk of the source file
+
+        Args:
+            count (int): Number of the Chunk to generate
+
+        Returns:
+            classes.chunk.Chunk: A Chunk object containing the portion of the 
+            File object beginning at (count * chunksize) bytes and ending at
+            ((count + 1) * chunksize - 1) bytes, with chunksize taken from the
+            RemoteFile initialization value
+        """
         return self.file.getChunk(count, self.chunksize)

classes/retry.py

@@ -1,13 +1,32 @@
 from paramiko.ssh_exception import SSHException
 
 class retry:
-    def __init__(self, exceptions=None):
+    """Decorator used to automatically retry operations throwing exceptions
+    """
+    def __init__(self, exceptions: tuple[BaseException] = None):
+        """Initializing the retry decorator
+
+        Args:
+            exceptions (tuple, optional): A tuple containing exception classes
+              that should be handled by the decorator. If none, handle only
+              paramiko.ssh_exception.SSHException. Defaults to None.
+        """
         self.exceptions = exceptions or (SSHException,)
     
     def __call__(self, f):
-        def wrapped_f(*args):
-            try:
-                f(*args)
-            except self.exceptions as e:
-                print("Caught expected exception: " + e)
+        """Return a function through the retry decorator
+
+        Args:
+            f (function): Function to wrap in the decorator
+
+        Returns:
+            function: Function wrapping the passed function
+        """
+        def wrapped_f(*args, **kwargs):
+            while True:
+                try:
+                    return f(*args, **kwargs)
+                except self.exceptions as e:
+                    print("Caught expected exception: " + repr(e))
+
         return wrapped_f

classes/shorethread.py

@@ -4,32 +4,49 @@ from classes.doghandler import DogHandler
 from watchdog.observers import Observer
 
 from multiprocessing import Process, Queue
+from typing import NoReturn
 
 import time
 import os.path
 
 
-class ShoreThread:
-    def __init__(self, files, directories):
+class ShoreThread(Process):
+    """Thread handling the discovery of shore-side file changes
+    """
+    def __init__(self, state: dict) -> None:
+        """Create a new ShoreThread object
+
+        Args:
+            state (dict): Dictionary containing the application state
+        """
         super().__init__()
         self._dogs = []
-        self.files = files
+        self._state = state
         self.queue = Queue()
-        self.directories = directories
 
-    def getAllFiles(self):
+    def getAllFiles(self) -> list:
+        """Return File objects for all files in all Directories
+
+        Returns:
+            list: List of all File objects discovered
+        """
         files = []
 
-        for directory in self.directories:
-            files.append(directory.getFiles())
+        for directory in self._state["config"].directories:
+            for f in directory.getFiles():
+                files.append(f)
 
         return files
 
-    def clearFiles(self):
-        del self.files[:]
+    def clearFiles(self) -> None:
+        """Clear the files variable in the application state
+        """
+        del self._state["files"][:]
 
-    def monitor(self):
-        for directory in self.directories:
+    def monitor(self) -> None:
+        """Initialize monitoring of Directories specified in configuration
+        """
+        for directory in self._state["config"].directories:
             print("Creating dog for " + str(directory.location))
             handler = DogHandler(directory, self.queue)
             dog = Observer()
@@ -37,27 +54,34 @@ class ShoreThread:
             dog.start()
             self._dogs.append(dog)
 
-    def run(self):
+    def run(self) -> NoReturn:
+        """Launch the ShoreThread and start monitoring for file changes
+        """
         print("Launched Shore Thread")
         self.getAllFiles()
         self.monitor()
-        try:
-            while True:
-                self.joinDogs()
-                self.processQueue()
-        except KeyboardInterrupt:
-            self.stop()
-            raise
+        
+        while True:
+            self.joinDogs()
+            self.processQueue()
 
-    def joinDogs(self):
+    def joinDogs(self) -> None:
+        """Join observers to receive updates on the queue
+        """
         for dog in self._dogs:
             dog.join(1)
 
-    def processQueue(self):
-        event = self.queue.get()
+    def processQueue(self) -> None:
+        """Handle events currently on the queue
+        """
+        event = self.queue.get() # Will block until an event is found
         print(event)
 
-    def stop(self):
+    def terminate(self, *args, **kwargs) -> None:
+        """Terminate observer threads, then terminate self
+        """
         for dog in self._dogs:
-            dog.stop()
+            dog.terminate()
             dog.join()
+
+        super().terminate(*args, **kwargs)

classes/vessel.py

@@ -4,45 +4,99 @@ from classes.file import File
 
 from paramiko.ssh_exception import SSHException
 
+from configparser import SectionProxy
+from typing import Optional, Union
+
 import pathlib
 
+
 class Vessel:
+    """Class describing a Vessel (= a replication destination)
+    """
     @classmethod
-    def fromConfig(cls, config):
+    def fromConfig(cls, config: SectionProxy):
+        """Create Vessel object from a Vessel section in the Config file
+
+        Args:
+            config (configparser.SectionProxy): Vessel section defining a 
+              Vessel
+
+        Raises:
+            ValueError: Raised if section does not contain Address parameter
+
+        Returns:
+            classes.vessel.Vessel: Vessel object for the vessel specified in
+              the config section
+        """
+
+        tempdir = None
+
         if "TempDir" in config.keys():
             tempdir = config["TempDir"]
-        else:
-            tempdir = "/tmp/.ContentMonster/"
-        if "Address" in config.keys():
-            return cls(config.name.split()[1], config["Address"], pathlib.Path(tempdir))
-        else:
-            raise ValueError("Definition for Vessel " + config.name.split()[1] + " does not contain Address!")
 
-    def __init__(self, name: str, address: str, tempdir: pathlib.Path):
+        if "Address" in config.keys():
+            return cls(config.name.split()[1], config["Address"], tempdir)
+        else:
+            raise ValueError("Definition for Vessel " +
+                             config.name.split()[1] + " does not contain Address!")
+
+    def __init__(self, name: str, address: str, tempdir: Optional[Union[str, pathlib.Path]]) -> None:
+        """Initialize new Vessel object
+
+        Args:
+            name (str): Name of the Vessel
+            address (str): Address (IP or resolvable hostname) of the Vessel
+            tempdir (pathlib.Path, optional): Temporary upload location on the
+              Vessel, to store Chunks in
+        """
         self.name = name
         self.address = address
-        self.tempdir = tempdir
+        self.tempdir = pathlib.Path(tempdir or "/tmp/.ContentMonster/")
         self._connection = None
-        self._uploaded = self.getUploadedFromDB()
+        self._uploaded = self.getUploadedFromDB() # Files already uploaded
 
     @property
-    def connection(self):
+    def connection(self) -> Connection:
+        """Get a Connection to the Vessel
+
+        Returns:
+            classes.connection.Connection: SSH/SFTP connection to the Vessel
+        """
+        # If a connection exists
         if self._connection:
             try:
+                # ... check if it is up
                 self._connection._listdir()
             except SSHException:
+                # ... and throw it away if it isn't
                 self._connection = None
+
+        # If no connection exists (anymore), set up a new one
         self._connection = self._connection or Connection(self)
         return self._connection
 
-    def getUploadedFromDB(self):
+    def getUploadedFromDB(self) -> list[str]:
+        """Get a list of files that have previously been uploaded to the Vessel
+
+        Returns:
+            list: List of UUIDs of Files that have been successfully uploaded
+        """
         db = Database()
         return db.getCompletionForVessel(self)
 
-    def currentUpload(self):
+    def currentUpload(self) -> File:
+        """Get the File that is currently being uploaded to this Vessel
+
+        Returns:
+            classes.file.File: File object representing the file currently
+              being uploaded
+        """
         db = Database()
-        directory, name, _ = db.getFileByUUID(fileuuid := self.connection.getCurrentUploadUUID())
+        directory, name, _ = db.getFileByUUID(
+            fileuuid := self.connection.getCurrentUploadUUID())
         return File(name, directory, fileuuid)
 
-    def clearTempDir(self):
-        return self.connection.clearTempDir()
+    def clearTempDir(self) -> None:
+        """Clean up the temporary directory on the Vessel 
+        """
+        self.connection.clearTempDir()

classes/vesselthread.py

@@ -1,18 +1,30 @@
 from multiprocessing import Process
 
+from classes.vessel import Vessel
+
 import time
 
 class VesselThread(Process):
-    def __init__(self, vessel, files):
+    """Thread processing uploads to a single vessel
+    """
+    def __init__(self, vessel: Vessel, state: dict):
+        """Initialize a new VesselThread
+
+        Args:
+            vessel (classes.vessel.Vessel): Vessel object to handle uploads for
+            state (dict): Dictionary containing the current application state
+        """
         super().__init__()
         self.vessel = vessel
-        self.files = files
+        self._state = state
 
     def run(self):
+        """Run thread and process uploads to the vessel
+        """
         print("Launched Vessel Thread for " + self.vessel.name)
         while True:
             try:
-                print(self.files[0])
+                print(self._state["files"][0])
             except:
-                print("Nothing.")
-            time.sleep(10)
+                pass
+            time.sleep(1)

worker.py

@@ -11,11 +11,13 @@ import time
 
 if __name__ == '__main__':
     config_path = pathlib.Path(__file__).parent.absolute() / "settings.ini"
-    config = MonsterConfig.fromFile(config_path)
+    config = MonsterConfig()
+    config.readFile(config_path)
 
     with Manager() as manager:
         state = manager.dict()
         state["files"] = manager.list()
+        state["config"] = config
 
         threads = []
 
@@ -24,11 +26,15 @@ if __name__ == '__main__':
             thread.start()
             threads.append(thread)
 
-        try:
-            shore = ShoreThread(state, config.directories)
-            shore.run()
-        except KeyboardInterrupt:
-            print("Keyboard interrupt received - stopping threads")
-            for thread in threads:
-                thread.kill()
-            exit()
+        shore = ShoreThread(state)
+        shore.start()
+
+        while True:
+            try:
+                time.sleep(10)
+            except KeyboardInterrupt:
+                print("Keyboard interrupt received - stopping threads")
+                shore.terminate()
+                for thread in threads:
+                    thread.terminate()
+                exit()