Add get_metadata_from_file_keys and use it

7 files changed, 91 insertions, 121 deletions

diff --git a/obnamlib/__init__.py b/obnamlib/__init__.py
index 9f2792f7..e4ecfd0e 100644
--- a/obnamlib/__init__.py
+++ b/obnamlib/__init__.py
@@ -168,7 +168,8 @@ from repo_interface import (
     REPO_FILE_DEV,
     REPO_FILE_INO,
     REPO_FILE_MD5,
-    REPO_FILE_INTEGER_KEYS)
+    REPO_FILE_INTEGER_KEYS,
+    metadata_file_key_mapping)
 
 from .delegator import RepositoryDelegator, GenerationId
 
diff --git a/obnamlib/delegator.py b/obnamlib/delegator.py
index e477d706..78eccc98 100644
--- a/obnamlib/delegator.py
+++ b/obnamlib/delegator.py
@@ -220,6 +220,11 @@ class RepositoryDelegator(obnamlib.RepositoryInterface):
         client = self._lookup_client_by_generation(generation_id)
         return client.remove_file(generation_id.gen_number, filename)
 
+    def get_metadata_from_file_keys(self, generation_id, filename):
+        client = self._lookup_client_by_generation(generation_id)
+        return client.get_metadata_from_file_keys(
+            generation_id.gen_number, filename)
+
     def get_file_key(self, generation_id, filename, key):
         if key not in self.get_allowed_file_keys():
             raise obnamlib.RepositoryFileKeyNotAllowed(
diff --git a/obnamlib/fmt_ga/client.py b/obnamlib/fmt_ga/client.py
index 95f4ac73..66a71ab5 100644
--- a/obnamlib/fmt_ga/client.py
+++ b/obnamlib/fmt_ga/client.py
@@ -262,6 +262,14 @@ class GAClient(object):
                 genspec=gen_number,
                 filename=filename)
 
+    def get_metadata_from_file_keys(self, gen_number, filename):
+        self._load_data()
+        self._require_file_exists(gen_number, filename)
+
+        generation = self._lookup_generation_by_gen_number(gen_number)
+        metadata_obj = generation.get_file_metadata()
+        return metadata_obj.get_metadata_from_file_keys(filename)
+
     def set_file_key(self, gen_number, filename, key, value):
         self._load_data()
         generation = self._lookup_generation_by_gen_number(gen_number)
@@ -523,27 +531,34 @@ class GAFileMetadata(object):
         else:
             return None
 
-    def set_file_keys_from_metadata(self, filename, file_metadata):
-        mapping = [
-            (obnamlib.REPO_FILE_MODE, 'st_mode'),
-            (obnamlib.REPO_FILE_MTIME_SEC, 'st_mtime_sec'),
-            (obnamlib.REPO_FILE_MTIME_NSEC, 'st_mtime_nsec'),
-            (obnamlib.REPO_FILE_ATIME_SEC, 'st_atime_sec'),
-            (obnamlib.REPO_FILE_ATIME_NSEC, 'st_atime_nsec'),
-            (obnamlib.REPO_FILE_NLINK, 'st_nlink'),
-            (obnamlib.REPO_FILE_SIZE, 'st_size'),
-            (obnamlib.REPO_FILE_UID, 'st_uid'),
-            (obnamlib.REPO_FILE_USERNAME, 'username'),
-            (obnamlib.REPO_FILE_GID, 'st_gid'),
-            (obnamlib.REPO_FILE_GROUPNAME, 'groupname'),
-            (obnamlib.REPO_FILE_SYMLINK_TARGET, 'target'),
-            (obnamlib.REPO_FILE_XATTR_BLOB, 'xattr'),
-            (obnamlib.REPO_FILE_BLOCKS, 'st_blocks'),
-            (obnamlib.REPO_FILE_DEV, 'st_dev'),
-            (obnamlib.REPO_FILE_INO, 'st_ino'),
-            (obnamlib.REPO_FILE_MD5, 'md5'),
-        ]
+    def get_metadata_from_file_keys(self, filename):
+        if filename in self._added_files:
+            return self._make_metadata(
+                lambda key: self._added_files.get_file_key(filename, key))
+        else:
+            dir_obj, dir_path, basename = self._get_dir_obj(filename)
+            # We've already verifed the file exists, so we don't need
+            # to handle the case where dir_obj is None.
+            assert dir_obj is not None
+
+            return self._make_metadata(
+                lambda key: dir_obj.get_file_key(basename, key))
 
+    def _make_metadata(self, get_value):
+        metadata = obnamlib.Metadata()
+
+        for key, field in obnamlib.metadata_file_key_mapping:
+            value = get_value(key)
+            if value is None:
+                if key in obnamlib.REPO_FILE_INTEGER_KEYS:
+                    value = 0
+                else:
+                    value = ''
+            setattr(metadata, field, value)
+
+        return metadata
+
+    def set_file_keys_from_metadata(self, filename, file_metadata):
         if filename in self._added_files:
             self._added_files.set_file_key(
                 filename, obnamlib.REPO_FILE_MODE, file_metadata.st_mode)
@@ -553,7 +568,7 @@ class GAFileMetadata(object):
         if not dir_obj:
             return False
 
-        for key, field in mapping:
+        for key, field in obnamlib.metadata_file_key_mapping:
             value = getattr(file_metadata, field)
             dir_obj.set_file_key(basename, key, value)
 
diff --git a/obnamlib/plugins/backup_plugin.py b/obnamlib/plugins/backup_plugin.py
index 15dcf21f..09ea3387 100644
--- a/obnamlib/plugins/backup_plugin.py
+++ b/obnamlib/plugins/backup_plugin.py
@@ -808,23 +808,7 @@ class BackupPlugin(obnamlib.ObnamPlugin):
         return False
 
     def get_metadata_from_generation(self, gen, pathname):
-        return obnamlib.Metadata(
-            st_mtime_sec=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_MTIME_SEC),
-            st_mtime_nsec=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_MTIME_NSEC),
-            st_mode=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_MODE),
-            st_nlink=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_NLINK),
-            st_size=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_SIZE),
-            st_uid=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_UID),
-            st_gid=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_GID),
-            xattr=self.repo.get_file_key(
-                gen, pathname, obnamlib.REPO_FILE_XATTR_BLOB))
+        return self.repo.get_metadata_from_file_keys(gen, pathname)
 
     def add_file_to_generation(self, filename, metadata):
         self.repo.add_file(self.new_generation, filename)
diff --git a/obnamlib/plugins/fuse_plugin.py b/obnamlib/plugins/fuse_plugin.py
index 2bf8d0a7..a52b77d6 100644
--- a/obnamlib/plugins/fuse_plugin.py
+++ b/obnamlib/plugins/fuse_plugin.py
@@ -282,8 +282,8 @@ class ObnamFuse(fuse.Fuse):
     def get_metadata_in_generation(self, path):
         tracing.trace('path=%r', path)
 
-        metadata = self.construct_metadata_object(
-            self.obnam.repo, *self.get_gen_path(path))
+        gen, filename = self.get_gen_path(path)
+        metadata = self.obnam.repo.get_metadata_from_file_keys(gen, filename)
 
         # FUSE does not allow negative timestamps, truncate to zero
         if metadata.st_atime_sec < 0:
@@ -293,35 +293,6 @@ class ObnamFuse(fuse.Fuse):
 
         return metadata
 
-    def construct_metadata_object(self, repo, gen, filename):
-        allowed = set(repo.get_allowed_file_keys())
-
-        def K(key):
-            if key in allowed:
-                return repo.get_file_key(gen, filename, key)
-            else:
-                return None
-
-        return obnamlib.Metadata(
-            st_atime_sec=K(obnamlib.REPO_FILE_ATIME_SEC),
-            st_atime_nsec=K(obnamlib.REPO_FILE_ATIME_NSEC),
-            st_mtime_sec=K(obnamlib.REPO_FILE_MTIME_SEC),
-            st_mtime_nsec=K(obnamlib.REPO_FILE_MTIME_NSEC),
-            st_blocks=K(obnamlib.REPO_FILE_BLOCKS),
-            st_dev=K(obnamlib.REPO_FILE_DEV),
-            st_gid=K(obnamlib.REPO_FILE_GID),
-            st_ino=K(obnamlib.REPO_FILE_INO),
-            st_mode=K(obnamlib.REPO_FILE_MODE),
-            st_nlink=K(obnamlib.REPO_FILE_NLINK),
-            st_size=K(obnamlib.REPO_FILE_SIZE),
-            st_uid=K(obnamlib.REPO_FILE_UID),
-            username=K(obnamlib.REPO_FILE_USERNAME),
-            groupname=K(obnamlib.REPO_FILE_GROUPNAME),
-            target=K(obnamlib.REPO_FILE_SYMLINK_TARGET),
-            xattr=K(obnamlib.REPO_FILE_XATTR_BLOB),
-            md5=K(obnamlib.REPO_FILE_MD5),
-            )
-
     def get_stat_in_generation(self, path):
         tracing.trace('path=%r', path)
         metadata = self.get_metadata_in_generation(path)
diff --git a/obnamlib/plugins/restore_plugin.py b/obnamlib/plugins/restore_plugin.py
index 3f85d74f..71266b62 100644
--- a/obnamlib/plugins/restore_plugin.py
+++ b/obnamlib/plugins/restore_plugin.py
@@ -198,42 +198,13 @@ class RestorePlugin(obnamlib.ObnamPlugin):
             self.app.ts['current'] = pathname
             self.restore_safely(gen, pathname)
 
-    def construct_metadata_object(self, gen, filename):
-        allowed = set(self.repo.get_allowed_file_keys())
-
-        def K(key):
-            if key in allowed:
-                return self.repo.get_file_key(gen, filename, key)
-            else:
-                return None
-
-        return obnamlib.Metadata(
-            st_atime_sec=K(obnamlib.REPO_FILE_ATIME_SEC),
-            st_atime_nsec=K(obnamlib.REPO_FILE_ATIME_NSEC),
-            st_mtime_sec=K(obnamlib.REPO_FILE_MTIME_SEC),
-            st_mtime_nsec=K(obnamlib.REPO_FILE_MTIME_NSEC),
-            st_blocks=K(obnamlib.REPO_FILE_BLOCKS),
-            st_dev=K(obnamlib.REPO_FILE_DEV),
-            st_gid=K(obnamlib.REPO_FILE_GID),
-            st_ino=K(obnamlib.REPO_FILE_INO),
-            st_mode=K(obnamlib.REPO_FILE_MODE),
-            st_nlink=K(obnamlib.REPO_FILE_NLINK),
-            st_size=K(obnamlib.REPO_FILE_SIZE),
-            st_uid=K(obnamlib.REPO_FILE_UID),
-            username=K(obnamlib.REPO_FILE_USERNAME),
-            groupname=K(obnamlib.REPO_FILE_GROUPNAME),
-            target=K(obnamlib.REPO_FILE_SYMLINK_TARGET),
-            xattr=K(obnamlib.REPO_FILE_XATTR_BLOB),
-            md5=K(obnamlib.REPO_FILE_MD5),
-            )
-
     def restore_safely(self, gen, pathname):
         try:
             dirname = os.path.dirname(pathname)
             if self.write_ok and not self.fs.exists('./' + dirname):
                 self.fs.makedirs('./' + dirname)
 
-            metadata = self.construct_metadata_object(gen, pathname)
+            metadata = self.repo.get_metadata_from_file_keys(gen, pathname)
 
             set_metadata = True
             if metadata.isdir():
diff --git a/obnamlib/repo_interface.py b/obnamlib/repo_interface.py
index d0d1521a..f51dbc56 100644
--- a/obnamlib/repo_interface.py
+++ b/obnamlib/repo_interface.py
@@ -94,6 +94,28 @@ def repo_key_name(key_value):
 WRONG_KEY = -1
 
 
+# A mapping between file keys and obnamlib.Metadata object fields.
+metadata_file_key_mapping = [
+    (REPO_FILE_MODE, 'st_mode'),
+    (REPO_FILE_MTIME_SEC, 'st_mtime_sec'),
+    (REPO_FILE_MTIME_NSEC, 'st_mtime_nsec'),
+    (REPO_FILE_ATIME_SEC, 'st_atime_sec'),
+    (REPO_FILE_ATIME_NSEC, 'st_atime_nsec'),
+    (REPO_FILE_NLINK, 'st_nlink'),
+    (REPO_FILE_SIZE, 'st_size'),
+    (REPO_FILE_UID, 'st_uid'),
+    (REPO_FILE_USERNAME, 'username'),
+    (REPO_FILE_GID, 'st_gid'),
+    (REPO_FILE_GROUPNAME, 'groupname'),
+    (REPO_FILE_SYMLINK_TARGET, 'target'),
+    (REPO_FILE_XATTR_BLOB, 'xattr'),
+    (REPO_FILE_BLOCKS, 'st_blocks'),
+    (REPO_FILE_DEV, 'st_dev'),
+    (REPO_FILE_INO, 'st_ino'),
+    (REPO_FILE_MD5, 'md5'),
+]
+
+
 class RepositoryClientListLockingFailed(obnamlib.ObnamError):
 
     msg = 'Repository client list could not be locked'
@@ -681,7 +703,28 @@ class RepositoryInterface(object):
         '''
         raise NotImplementedError()
 
+    def get_metadata_from_file_keys(self, generation_id, filename):
+        '''Return a Metadata constructed from the file's keys.
+
+        This is equivalent to creating the Metadata object and calling
+        get_file_key for every allowed key and setting the
+        corresponding field in the Metadata object. It may be faster
+        on some repository formats, however.
+
+        '''
+
+        metadata = obnamlib.Metadata()
+
+        allowed = set(self.get_allowed_file_keys())
+        for key, field in obnamlib.metadata_file_key_mapping:
+            if key in allowed:
+                value = self.get_file_key(generation_id, filename, key)
+                setattr(metadata, field, value)
+
+        return metadata
+
     def set_file_key(self, generation_id, filename, key, value):
+
         '''Set value for a file key.
 
         It is an error to set the value for a file key if the file does
@@ -698,28 +741,8 @@ class RepositoryInterface(object):
 
         '''
 
-        mapping = [
-            (REPO_FILE_MODE, 'st_mode'),
-            (REPO_FILE_MTIME_SEC, 'st_mtime_sec'),
-            (REPO_FILE_MTIME_NSEC, 'st_mtime_nsec'),
-            (REPO_FILE_ATIME_SEC, 'st_atime_sec'),
-            (REPO_FILE_ATIME_NSEC, 'st_atime_nsec'),
-            (REPO_FILE_NLINK, 'st_nlink'),
-            (REPO_FILE_SIZE, 'st_size'),
-            (REPO_FILE_UID, 'st_uid'),
-            (REPO_FILE_USERNAME, 'username'),
-            (REPO_FILE_GID, 'st_gid'),
-            (REPO_FILE_GROUPNAME, 'groupname'),
-            (REPO_FILE_SYMLINK_TARGET, 'target'),
-            (REPO_FILE_XATTR_BLOB, 'xattr'),
-            (REPO_FILE_BLOCKS, 'st_blocks'),
-            (REPO_FILE_DEV, 'st_dev'),
-            (REPO_FILE_INO, 'st_ino'),
-            (REPO_FILE_MD5, 'md5'),
-        ]
-
         allowed = set(self.get_allowed_file_keys())
-        for key, field in mapping:
+        for key, field in obnamlib.metadata_file_key_mapping:
             if key in allowed:
                 self.set_file_key(
                     generation_id, filename, key, getattr(metadata, field))