Basic install function

bpkg_manager/subproc.py

@@ -31,6 +31,27 @@ class Progress(SubprocMessage):
     def __init__(self, progress: float):
         self.progress = progress
 
+class SubprocError(SubprocMessage):
+    """Superclass for all fatal error messages sent from the subprocess."""
+
+    def __init__(self, message: str):
+        self.message = message
+
+class SubprocWarning(SubprocMessage):
+    """Superclass for all non-fatal warning messages sent from the subprocess."""
+
+    def __init__(self, message: str):
+        self.message = message
+
+class InstallError(SubprocError):
+    """Sent when there was an error installing something."""
+
+class FileConflictError(InstallError):
+    """Sent when installation would overwrite existing files."""
+
+    def __init__(self, message: str, conflicts: list):
+        self.message = message
+        self.conflicts = conflicts
 
 class DownloadError(SubprocMessage):
     """Sent when there was an error downloading something."""
@@ -48,6 +69,9 @@ class Aborted(SubprocMessage):
     """Sent as response to Abort message."""
 
 
+class InstallException(Exception):
+    """Raised when there is an error during installation"""
+
 def _download(pipe_to_blender, package_url: str, download_dir: pathlib.Path) -> pathlib.Path:
     """Downloads the given package
 
@@ -77,6 +101,8 @@ def _download(pipe_to_blender, package_url: str, download_dir: pathlib.Path) ->
         log.warning('Server did not send content length, cannot report progress.')
         content_length = float('inf')
 
+    # TODO: check if there's enough disk space.
+
     # TODO: get filename from Content-Disposition header, if available.
     # TODO: use urllib.parse to parse the URL.
     local_filename = package_url.split('/')[-1] or 'download.tmp'
@@ -105,11 +131,74 @@ def _download(pipe_to_blender, package_url: str, download_dir: pathlib.Path) ->
             # leave 30% "progress" for installation of the package.
             pipe_to_blender.send(Progress(downloaded_length / content_length))
 
-    pipe_to_blender.send(Success())
     return local_fpath
 
+def _install(pipe_to_blender, pkgpath: pathlib.Path, dest: pathlib.Path):
+    """Extracts/moves package at `pkgpath` to `dest`"""
+    import zipfile
 
-def download_and_install(pipe_to_blender, package_url: str):
+    pipe_to_blender.send(Progress(0.0))
+
+    if not pkgpath.is_file():
+        log.error("File to install isn't a file: %s", pkgpath)
+        pipe_to_blender.send(InstallError("Package is not a file"))
+        raise InstallException
+
+    if not dest.is_dir():
+        log.error("Destination for install isn't a directory: %s", dest)
+        pipe_to_blender.send(InstallError("Destination is not a directory"))
+        raise InstallException
+
+    # TODO: check to make sure addon/package isn't already installed elsewhere
+
+    # The following is adapted from `addon_install` in bl_operators/wm.py
+
+    # check to see if the file is in compressed format (.zip)
+    if zipfile.is_zipfile(pkgpath):
+        try:
+            file_to_extract = zipfile.ZipFile(str(pkgpath), 'r')
+        except Exception as err:
+            pipe_to_blender.send(InstallError("Failed to read zip file: %s" % err))
+            raise InstallException from err
+
+        conflicts = [f for f in file_to_extract.namelist() if (dest / f).exists()]
+        if len(conflicts) > 0:
+            # TODO: handle this better than just dumping a list of all files
+            pipe_to_blender.send(FileConflictError("Installation would overwrite: %s" % conflicts, conflicts))
+            raise InstallException
+
+        try:
+            file_to_extract.extractall(str(dest))
+        except Exception as err:
+            pipe_to_blender.send(InstallError("Failed to extract zip file to '%s': %s" % (dest, err)))
+            raise InstallException from err
+
+    else:
+        dest_file = (dest / pkgpath.name)
+
+        if dest_file.exists():
+            pipe_to_blender.send(FileConflictError("Installation would overwrite %s" % dest_file, [dest_file]))
+            raise InstallException
+
+        import shutil
+
+        try:
+            shutil.copyfile(str(pkgpath), str(dest_file))
+        except Exception as err:
+            pipe_to_blender.send(InstallError("Failed to copy file to '%s': %s" % (dest, err)))
+            raise InstallException from err
+
+    try:
+        pkgpath.unlink()
+    except Exception as err:
+        pipe_to_blender.send(SubprocWarning("Failed to remove package from cache: %s" % err))
+        raise InstallException from err
+
+    pipe_to_blender.send(Progress(1.0))
+    return
+
+
+def download_and_install(pipe_to_blender, package_url: str, install_dir: pathlib.Path):
     """Downloads and installs the given package."""
 
     from . import cache
@@ -123,8 +212,13 @@ def download_and_install(pipe_to_blender, package_url: str):
         log.debug('Download failed/aborted, not going to install anything.')
         return
 
-    # TODO: actually install the package
-    log.warning('Installing is not actually implemented, install %s yourself.', downloaded)
+    # Only send success if _install doesn't throw an exception
+    # Maybe not the best way to do this? (will also catch exceptions which occur during message sending)
+    try:
+        _install(pipe_to_blender, downloaded, install_dir)
+        pipe_to_blender.send(Success())
+    except:
+        raise
 
 
 def debug_hang():