NXDRIVE-1231: Improve and move to public Report.export_logs()

Also rework CustomMemoryHandler.get_buffer() to properly handle the `size` argument.

docs/technical_changes.md

@@ -8,6 +8,7 @@
 - Removed `AbstractOSIntegration.is_windows()`
 - Removed `Application.get_htmlpage()`
 - Removed `Application.get_cache_folder()`
+- Removed `CustomMemoryHandler.flush()`
 - Added `Engine.init_remote()`
 - Changed `Engine(..., remote_doc_client_factory, remote_fs_client_factory, remote_filtered_fs_client_factory` to `Engine(..., remote_cls, filtered_remote_cls, local_cls)`
 - Removed `Engine.get_abspath()`
@@ -105,6 +106,7 @@
 - Added gui/settings.py::`SettingsView`
 - Added gui/systray.py::`SystrayView`
 - Added gui/view.py
+- Moved logging_config.py::`MAX_LOG_DISPLAYED` constants.py
 - Moved manager.py::`EngineTypeMissing` exception to exceptions.py
 - Moved manager.py::`FolderAlreadyUsed` exception to exceptions.py
 - Moved manager.py::`MissingToken` to client/proxy.py

nxdrive/constants.py

@@ -11,6 +11,7 @@
 TIMEOUT = 20
 TX_TIMEOUT = 300
 FILE_BUFFER_SIZE = 1024 ** 2
+MAX_LOG_DISPLAYED = 50000
 
 DOWNLOAD_TMP_FILE_PREFIX = "."
 DOWNLOAD_TMP_FILE_SUFFIX = ".nxpart"

nxdrive/logging_config.py

@@ -4,11 +4,13 @@
 import logging
 import os
 from logging.handlers import BufferingHandler, TimedRotatingFileHandler
+from typing import List
 from zipfile import ZIP_DEFLATED, ZipFile
 
+from . import constants
 from .options import Options
 
-__all__ = ("MAX_LOG_DISPLAYED", "configure", "get_handler")
+__all__ = ("configure", "get_handler")
 
 FILE_HANDLER = None
 TRACE = 5
@@ -28,7 +30,6 @@
 _logging_context = dict()
 
 is_logging_configured = False
-MAX_LOG_DISPLAYED = 50000
 
 
 def add_trace_level() -> None:
@@ -53,27 +54,21 @@ def trace(self, message, *args, **kws):
 
 
 class CustomMemoryHandler(BufferingHandler):
-    def __init__(self, capacity: int = MAX_LOG_DISPLAYED) -> None:
+    def __init__(self, capacity: int = constants.MAX_LOG_DISPLAYED) -> None:
         super().__init__(capacity)
-        self.old_buffer_ = None
 
-    def flush(self) -> None:
+    def get_buffer(self, size: int) -> List[str]:
+        """
+        If `size` is positive, returns the first `size` lines from the memory buffer.
+        If `size` is negative, returns the last `size` lines from the memory buffer.
+        By default, `size` is equal to the buffer length, so the entire buffer is returned.
+        """
         self.acquire()
         try:
-            self.old_buffer_, self.buffer = self.buffer[:], []
+            return self.buffer[:size] if size > 0 else self.buffer[size:]
         finally:
             self.release()
 
-    def get_buffer(self, size: int) -> None:
-        self.acquire()
-        try:
-            result = self.buffer[:]
-            if len(result) < size and self.old_buffer_:
-                result += self.old_buffer_[size - len(result) - 1 :]
-        finally:
-            self.release()
-        return result
-
 
 class TimedCompressedRotatingFileHandler(TimedRotatingFileHandler):
     """

nxdrive/report.py

@@ -2,10 +2,11 @@
 import os
 from datetime import datetime
 from logging import getLogger
-from typing import Generator
+from typing import Iterator
 from zipfile import ZIP_DEFLATED, ZIP_STORED, ZipFile
 
-from .logging_config import MAX_LOG_DISPLAYED, get_handler
+from . import constants
+from .logging_config import get_handler
 
 __all__ = ("Report",)
 
@@ -91,29 +92,28 @@ def get_path(self) -> str:
         return self._zipfile
 
     @staticmethod
-    def _export_logs() -> Generator[str, None, None]:
+    def export_logs(lines: int = constants.MAX_LOG_DISPLAYED) -> Iterator[bytes]:
         """
         Export all lines from the memory logger.
 
         :return bytes: bytes needed by zipfile.writestr()
         """
 
         handler = get_handler(getLogger(), "memory")
-        log_buffer = handler.get_buffer(MAX_LOG_DISPLAYED)
+        log_buffer = handler.get_buffer(lines)
 
         for record in log_buffer:
             try:
                 line = handler.format(record)
             except:
                 try:
-                    log.error("Logging record error: %r", record)
+                    yield "Logging record error: {record!r}"
                 except:
                     pass
-                continue
-
-            if not isinstance(line, bytes):
-                line = line.encode(errors="replace")
-            yield line
+            else:
+                if not isinstance(line, bytes):
+                    line = line.encode(errors="replace")
+                yield line
 
     def generate(self) -> None:
         """ Create the ZIP report with all interesting files. """
@@ -133,7 +133,7 @@ def generate(self) -> None:
 
             # Memory logger -> debug.log
             try:
-                lines = b"\n".join(list(self._export_logs()))
+                lines = b"\n".join(self.export_logs())
                 zip_.writestr("debug.log", lines, compress_type=ZIP_DEFLATED)
             except:
                 log.exception("Impossible to get lines from the memory logger")