[models] Add type hints and migrate downloader models to dataclasses

legendary/models/downloading.py

@@ -1,165 +1,179 @@
 # coding: utf-8
 
+from dataclasses import dataclass
+from typing import Union
 
-class DownloaderTask:
+from .manifest import ManifestComparison
-    def __init__(self, url=None, chunk_guid=None, shm=None, kill=False):
-        self.url = url
-        self.guid = chunk_guid
-        self.shm = shm
-        self.kill = kill
-
-
-class DownloaderTaskResult:
-    def __init__(self, success, chunk_guid, shm, url, size=None,
-                 compressed_size=None, time_delta=None):
-        self.success = success
-        self.shm = shm
-        self.size = size
-        self.compressed_size = compressed_size
-        self.guid = chunk_guid
-        self.time_delta = time_delta
-        self.url = url
-
-
-class WriterTask:
-    """
-    Writing task for FileWorker, including some metadata that is required.
-    """
-
-    def __init__(self, filename, chunk_offset=0, chunk_size=0, chunk_guid=None, close=False,
-                 shared_memory=None, cache_file='', old_file='', release_memory=False, rename=False,
-                 empty=False, kill=False, delete=False, old_filename='', fopen=False, silent=False):
-        self.filename = filename
-        self.empty = empty
-        self.shm = shared_memory
-        self.chunk_offset = chunk_offset
-        self.chunk_size = chunk_size
-        self.chunk_guid = chunk_guid
-        self.release_memory = release_memory
-
-        # reading from a cached chunk instead of memory
-        self.cache_file = cache_file
-        self.old_file = old_file
-        self.open = fopen
-        self.close = close
-        self.delete = delete
-        self.rename = rename
-        self.old_filename = old_filename
-
-        self.silent = silent  # disable logging
-        self.kill = kill  # final task for worker (quit)
-
-
-class WriterTaskResult:
-    def __init__(self, success, filename='', chunk_guid='',
-                 release_memory=False, shm=None, size=0,
-                 kill=False, closed=False, time_delta=None):
-        self.success = success
-        self.filename = filename
-        self.chunk_guid = chunk_guid
-        self.release_memory = release_memory
-        self.shm = shm
-        self.size = size
-        self.kill = kill
-        self.closed = closed
-        self.time_delta = time_delta
-
-
-class UIUpdate:
-    """
-    Status update object sent from the manager to the CLI/GUI to update status indicators
-    """
-
-    def __init__(self, progress, download_speed, write_speed, read_speed,
-                 memory_usage, current_filename=''):
-        self.progress = progress
-        self.download_speed = download_speed
-        self.write_speed = write_speed
-        self.read_speed = read_speed
-        self.current_filename = current_filename
-        self.memory_usage = memory_usage
 
 
+@dataclass
 class SharedMemorySegment:
     """
     Segment of the shared memory used for one Chunk
     """
-
+    offset: int = 0
-    def __init__(self, offset=0, end=1024 * 1024):
+    end: int = 1024 * 1024
-        self.offset = offset
-        self.end = end
 
     @property
     def size(self):
         return self.end - self.offset
 
 
+@dataclass
+class DownloaderTask:
+    """
+    Task submitted to the download worker
+    """
+    url: Union[str, None] = None
+    chunk_guid: Union[int, None] = None
+    shm: Union[SharedMemorySegment, None] = None
+    kill: bool = False
+
+
+@dataclass
+class DownloaderTaskResult:
+    """
+    Result of DownloaderTask provided by download workers
+    """
+    success: bool
+    chunk_guid: int
+    shm: SharedMemorySegment
+    url: str
+    size: Union[int, None] = None
+    compressed_size: Union[int, None] = None
+    time_delta: Union[int, None] = None
+
+
+@dataclass
 class ChunkTask:
-    def __init__(self, chunk_guid, chunk_offset=0, chunk_size=0, cleanup=False, chunk_file=None):
+    """
-        """
+    A task describing a single read of a (partial) chunk from memory or an existing file
-        Download manager chunk task
+    """
-
+    chunk_guid: int
-        :param chunk_guid: GUID of chunk
+    chunk_offset: int = 0
-        :param cleanup: whether or not this chunk can be removed from disk/memory after it has been written
+    chunk_size: int = 0
-        :param chunk_offset: Offset into file or shared memory
+    # Whether this chunk can be removed from memory/disk after having been written
-        :param chunk_size: Size to read from file or shared memory
+    cleanup: bool = False
-        :param chunk_file: Either cache or existing game file this chunk is read from if not using shared memory
+    # Path to the file the chunk is read from (if not from memory)
-        """
+    chunk_file: Union[str, None] = None
-        self.chunk_guid = chunk_guid
-        self.cleanup = cleanup
-        self.chunk_offset = chunk_offset
-        self.chunk_size = chunk_size
-        self.chunk_file = chunk_file
 
 
+@dataclass
 class FileTask:
-    def __init__(self, filename, delete=False, empty=False, fopen=False, close=False,
+    """
-                 rename=False, temporary_filename=None, silent=False):
+    A task describing some operation on the filesystem
-        """
+    """
-        Download manager Task for a file
+    filename: str
-
+    # just create a 0-byte file
-        :param filename: name of the file
+    empty: bool = False
-        :param delete: if this is a file to be deleted, if rename is true, delete filename before renaming
+    open: bool = False
-        :param empty: if this is an empty file that just needs to be "touch"-ed (may not have chunk tasks)
+    close: bool = False
-
+    rename: bool = False
-        :param temporary_filename: If rename is true: Filename to rename from.
+    # Deletes the file, if rename is true, this will remove an existing file with the target name
-        """
+    delete: bool = False
-        self.filename = filename
+    silent: bool = False
-        self.delete = delete
+    # If rename is true, this is the name of the file to be renamed
-        self.empty = empty
+    temporary_filename: Union[str, None] = None
-        self.open = fopen
-        self.close = close
-        self.rename = rename
-        self.temporary_filename = temporary_filename
-        self.silent = silent
 
     @property
     def is_reusing(self):
         return self.temporary_filename is not None
 
 
+@dataclass
+class WriterTask:
+    """
+    Task for FileWriter worker process, describing an operation on the filesystem
+    """
+    filename: str
+
+    chunk_offset: int = 0
+    chunk_size: int = 0
+    chunk_guid: Union[int, None] = None
+
+    # Just create an empty file
+    empty: bool = False
+    # Whether shared memory segment shall be released back to the pool on completion
+    release_memory: bool = False
+    shared_memory: Union[SharedMemorySegment, None] = None
+
+    # File to read old chunk from, disk chunk cache or old game file
+    old_file: Union[str, None] = None
+    cache_file: Union[str, None] = None
+
+    open: bool = False
+    close: bool = False
+    delete: bool = False
+    # Do not log deletion failures
+    silent: bool = False
+
+    rename: bool = False
+    # Filename to rename from
+    old_filename: Union[str, None] = None
+
+    # Instruct worker to terminate
+    kill: bool = False
+
+
+@dataclass
+class WriterTaskResult:
+    """
+    Result from the FileWriter worker
+    """
+    success: bool
+    filename: Union[str, None] = None
+    size: int = 0
+    chunk_guid: Union[int, None] = None
+
+    shared_memory: Union[SharedMemorySegment, None] = None
+    release_memory: bool = False
+    closed: bool = False
+    time_delta: Union[float, None] = None
+
+    # Worker terminated, instructs results handler to also stop
+    kill: bool = False
+
+
+@dataclass
+class UIUpdate:
+    """
+    Status update object sent from the manager to the CLI/GUI to update status indicators
+    """
+    progress: float
+    download_speed: float
+    write_speed: float
+    read_speed: float
+    memory_usage: float
+    current_filename: Union[str, None] = None
+
+
+@dataclass
 class AnalysisResult:
-    def __init__(self):
+    """
-        self.dl_size = 0
+    Result of processing a manifest for downloading
-        self.uncompressed_dl_size = 0
+    """
-        self.install_size = 0
+    dl_size: int = 0
-        self.reuse_size = 0
+    uncompressed_dl_size: int = 0
-        self.biggest_file_size = 0
+    install_size: int = 0
-        self.unchanged_size = 0
+    reuse_size: int = 0
-        self.biggest_chunk = 0
+    biggest_file_size: int = 0
-        self.min_memory = 0
+    unchanged_size: int = 0
-        self.num_chunks = 0
+    biggest_chunk: int = 0
-        self.num_chunks_cache = 0
+    min_memory: int = 0
-        self.num_files = 0
+    num_chunks: int = 0
-        self.removed = 0
+    num_chunks_cache: int = 0
-        self.added = 0
+    num_files: int = 0
-        self.changed = 0
+    removed: int = 0
-        self.unchanged = 0
+    added: int = 0
-        self.manifest_comparison = None
+    changed: int = 0
+    unchanged: int = 0
+    manifest_comparison: Union[ManifestComparison, None] = None
 
 
+@dataclass
 class ConditionCheckResult:
-    """Result object used in Core to identify problems that would prevent an installation from succeeding"""
+    """
-    def __init__(self, failures=None, warnings=None):
+    Result of install condition checks
-        self.failures = failures
+    """
-        self.warnings = warnings
+    failures: Union[list, None] = None
+    warnings: Union[list, None] = None