Fixed #20485 -- Refactored loaddata for speed.

Thanks Anssi for reporting this performance bottleneck.

django/core/management/commands/loaddata.py

@@ -1,7 +1,8 @@
 from __future__ import unicode_literals
 
-import os
+import glob
 import gzip
+import os
 import zipfile
 from optparse import make_option
 import warnings
@@ -12,9 +13,9 @@ from django.core.management.base import BaseCommand, CommandError
 from django.core.management.color import no_style
 from django.db import (connections, router, transaction, DEFAULT_DB_ALIAS,
       IntegrityError, DatabaseError)
-from django.db.models import get_apps
+from django.db.models import get_app_paths
 from django.utils.encoding import force_text
-from django.utils._os import upath
+from django.utils.functional import cached_property, memoize
 from itertools import product
 
 try:
@@ -44,9 +45,8 @@ class Command(BaseCommand):
 
         if not len(fixture_labels):
             raise CommandError(
-                "No database fixture specified. Please provide the path of at "
+                    "No database fixture specified. Please provide the path "
-                "least one fixture in the command line."
+                    "of at least one fixture in the command line.")
-            )
 
         self.verbosity = int(options.get('verbosity'))
 
@@ -69,37 +69,18 @@ class Command(BaseCommand):
         self.fixture_object_count = 0
         self.models = set()
 
-        class SingleZipReader(zipfile.ZipFile):
+        self.serialization_formats = serializers.get_public_serializer_formats()
-            def __init__(self, *args, **kwargs):
+        self.compression_formats = {
-                zipfile.ZipFile.__init__(self, *args, **kwargs)
-                if settings.DEBUG:
-                    assert len(self.namelist()) == 1, "Zip-compressed fixtures must contain only one file."
-            def read(self):
-                return zipfile.ZipFile.read(self, self.namelist()[0])
-
-        self.compression_types = {
             None:   open,
             'gz':   gzip.GzipFile,
             'zip':  SingleZipReader
         }
         if has_bz2:
-            self.compression_types['bz2'] = bz2.BZ2File
+            self.compression_formats['bz2'] = bz2.BZ2File
-
-        app_module_paths = []
-        for app in get_apps():
-            if hasattr(app, '__path__'):
-                # It's a 'models/' subpackage
-                for path in app.__path__:
-                    app_module_paths.append(upath(path))
-            else:
-                # It's a models.py module
-                app_module_paths.append(upath(app.__file__))
-
-        app_fixtures = [os.path.join(os.path.dirname(path), 'fixtures') for path in app_module_paths]
 
         with connection.constraint_checks_disabled():
             for fixture_label in fixture_labels:
-                self.load_label(fixture_label, app_fixtures)
+                self.load_label(fixture_label)
 
         # Since we disabled constraint checks, we must manually check for
         # any invalid keys that might have been added
@@ -124,97 +105,30 @@ class Command(BaseCommand):
 
         if self.verbosity >= 1:
             if self.fixture_object_count == self.loaded_object_count:
-                self.stdout.write("Installed %d object(s) from %d fixture(s)" % (
+                self.stdout.write("Installed %d object(s) from %d fixture(s)" %
-                    self.loaded_object_count, self.fixture_count))
+                    (self.loaded_object_count, self.fixture_count))
             else:
-                self.stdout.write("Installed %d object(s) (of %d) from %d fixture(s)" % (
+                self.stdout.write("Installed %d object(s) (of %d) from %d fixture(s)" %
-                    self.loaded_object_count, self.fixture_object_count, self.fixture_count))
+                    (self.loaded_object_count, self.fixture_object_count, self.fixture_count))
 
-    def load_label(self, fixture_label, app_fixtures):
+    def load_label(self, fixture_label):
-
+        """
-        parts = fixture_label.split('.')
+        Loads fixtures files for a given label.
-
+        """
-        if len(parts) > 1 and parts[-1] in self.compression_types:
+        for fixture_file, fixture_dir, fixture_name in self.find_fixtures(fixture_label):
-            compression_formats = [parts[-1]]
+            _, ser_fmt, cmp_fmt = self.parse_name(os.path.basename(fixture_file))
-            parts = parts[:-1]
+            open_method = self.compression_formats[cmp_fmt]
-        else:
+            fixture = open_method(fixture_file, 'r')
-            compression_formats = self.compression_types.keys()
-
-        if len(parts) == 1:
-            fixture_name = parts[0]
-            formats = serializers.get_public_serializer_formats()
-        else:
-            fixture_name, format = '.'.join(parts[:-1]), parts[-1]
-            if format in serializers.get_public_serializer_formats():
-                formats = [format]
-            else:
-                formats = []
-
-        if formats:
-            if self.verbosity >= 2:
-                self.stdout.write("Loading '%s' fixtures..." % fixture_name)
-        else:
-            raise CommandError(
-                "Problem installing fixture '%s': %s is not a known serialization format." %
-                    (fixture_name, format))
-
-        if os.path.isabs(fixture_name):
-            fixture_dirs = [fixture_name]
-        else:
-            fixture_dirs = app_fixtures + list(settings.FIXTURE_DIRS) + ['']
-
-        label_found = False
-        for fixture_dir in fixture_dirs:
-            found = self.process_dir(fixture_dir, fixture_name,
-                compression_formats, formats)
-            label_found = label_found or found
-
-        if fixture_name != 'initial_data' and not label_found:
-            warnings.warn("No fixture named '%s' found." % fixture_name)
-
-    def process_dir(self, fixture_dir, fixture_name, compression_formats,
-                    serialization_formats):
-
-        humanize = lambda dirname: "'%s'" % dirname if dirname else 'absolute path'
-
-        if self.verbosity >= 2:
-            self.stdout.write("Checking %s for fixtures..." % humanize(fixture_dir))
-
-        label_found = False
-        for combo in product([self.using, None], serialization_formats, compression_formats):
-            database, format, compression_format = combo
-            file_name = '.'.join(
-                p for p in [
-                    fixture_name, database, format, compression_format
-                ]
-                if p
-            )
-
-            if self.verbosity >= 3:
-                self.stdout.write("Trying %s for %s fixture '%s'..." % \
-                    (humanize(fixture_dir), file_name, fixture_name))
-            full_path = os.path.join(fixture_dir, file_name)
-            open_method = self.compression_types[compression_format]
             try:
-                fixture = open_method(full_path, 'r')
-            except IOError:
-                if self.verbosity >= 2:
-                    self.stdout.write("No %s fixture '%s' in %s." % \
-                        (format, fixture_name, humanize(fixture_dir)))
-            else:
-                try:
-                    if label_found:
-                        raise CommandError("Multiple fixtures named '%s' in %s. Aborting." %
-                            (fixture_name, humanize(fixture_dir)))
-
                 self.fixture_count += 1
                 objects_in_fixture = 0
                 loaded_objects_in_fixture = 0
                 if self.verbosity >= 2:
-                        self.stdout.write("Installing %s fixture '%s' from %s." % \
+                    self.stdout.write("Installing %s fixture '%s' from %s." %
-                            (format, fixture_name, humanize(fixture_dir)))
+                        (ser_fmt, fixture_name, humanize(fixture_dir)))
 
-                    objects = serializers.deserialize(format, fixture, using=self.using, ignorenonexistent=self.ignore)
+                objects = serializers.deserialize(ser_fmt, fixture,
+                    using=self.using, ignorenonexistent=self.ignore)
 
                 for obj in objects:
                     objects_in_fixture += 1
@@ -234,10 +148,9 @@ class Command(BaseCommand):
 
                 self.loaded_object_count += loaded_objects_in_fixture
                 self.fixture_object_count += objects_in_fixture
-                    label_found = True
             except Exception as e:
                 if not isinstance(e, CommandError):
-                        e.args = ("Problem installing fixture '%s': %s" % (full_path, e),)
+                    e.args = ("Problem installing fixture '%s': %s" % (fixture_file, e),)
                 raise
             finally:
                 fixture.close()
@@ -246,7 +159,120 @@ class Command(BaseCommand):
             # error was encountered during fixture loading.
             if objects_in_fixture == 0:
                 raise CommandError(
-                        "No fixture data found for '%s'. (File format may be invalid.)" %
+                        "No fixture data found for '%s'. "
-                            (fixture_name))
+                        "(File format may be invalid.)" % fixture_name)
 
-        return label_found
+    def _find_fixtures(self, fixture_label):
+        """
+        Finds fixture files for a given label.
+        """
+        fixture_name, ser_fmt, cmp_fmt = self.parse_name(fixture_label)
+        databases = [self.using, None]
+        cmp_fmts = list(self.compression_formats.keys()) if cmp_fmt is None else [cmp_fmt]
+        ser_fmts = serializers.get_public_serializer_formats() if ser_fmt is None else [ser_fmt]
+
+        # Check kept for backwards-compatibility; it doesn't look very useful.
+        if '.' in fixture_name:
+            raise CommandError(
+                    "Problem installing fixture '%s': %s is not a known "
+                    "serialization format." % tuple(fixture_name.rsplit('.')))
+
+        if self.verbosity >= 2:
+            self.stdout.write("Loading '%s' fixtures..." % fixture_name)
+
+        if os.path.isabs(fixture_name):
+            fixture_dirs = [os.path.dirname(fixture_name)]
+            fixture_name = os.path.basename(fixture_name)
+        else:
+            fixture_dirs = self.fixture_dirs
+
+        suffixes = ('.'.join(ext for ext in combo if ext)
+                for combo in product(databases, ser_fmts, cmp_fmts))
+        targets = set('.'.join((fixture_name, suffix)) for suffix in suffixes)
+
+        fixture_files = []
+        for fixture_dir in fixture_dirs:
+            if self.verbosity >= 2:
+                self.stdout.write("Checking %s for fixtures..." % humanize(fixture_dir))
+            fixture_files_in_dir = []
+            for candidate in glob.iglob(os.path.join(fixture_dir, fixture_name + '*')):
+                if os.path.basename(candidate) in targets:
+                    # Save the fixture_dir and fixture_name for future error messages.
+                    fixture_files_in_dir.append((candidate, fixture_dir, fixture_name))
+
+            if self.verbosity >= 2 and not fixture_files_in_dir:
+                self.stdout.write("No fixture '%s' in %s." %
+                                  (fixture_name, humanize(fixture_dir)))
+
+            # Check kept for backwards-compatibility; it isn't clear why
+            # duplicates are only allowed in different directories.
+            if len(fixture_files_in_dir) > 1:
+                raise CommandError(
+                        "Multiple fixtures named '%s' in %s. Aborting." %
+                        (fixture_name, humanize(fixture_dir)))
+            fixture_files.extend(fixture_files_in_dir)
+
+        if fixture_name != 'initial_data' and not fixture_files:
+            # Warning kept for backwards-compatibility; why not an exception?
+            warnings.warn("No fixture named '%s' found." % fixture_name)
+
+        return fixture_files
+
+    _label_to_fixtures_cache = {}
+    find_fixtures = memoize(_find_fixtures, _label_to_fixtures_cache, 2)
+
+    @cached_property
+    def fixture_dirs(self):
+        """
+        Return a list of fixture directories.
+
+        The list contains the 'fixtures' subdirectory of each installed
+        application, if it exists, the directories in FIXTURE_DIRS, and the
+        current directory.
+        """
+        dirs = []
+        for path in get_app_paths():
+            d = os.path.join(os.path.dirname(path), 'fixtures')
+            if os.path.isdir(d):
+                dirs.append(d)
+        dirs.extend(list(settings.FIXTURE_DIRS))
+        dirs.append('')
+        dirs = [os.path.abspath(os.path.realpath(d)) for d in dirs]
+        return dirs
+
+    def parse_name(self, fixture_name):
+        """
+        Splits fixture name in name, serialization format, compression format.
+        """
+        parts = fixture_name.rsplit('.', 2)
+
+        if len(parts) > 1 and parts[-1] in self.compression_formats:
+            cmp_fmt = parts[-1]
+            parts = parts[:-1]
+        else:
+            cmp_fmt = None
+
+        if len(parts) > 1 and parts[-1] in self.serialization_formats:
+            ser_fmt = parts[-1]
+            parts = parts[:-1]
+        else:
+            ser_fmt = None
+
+        name = '.'.join(parts)
+
+        return name, ser_fmt, cmp_fmt
+
+
+class SingleZipReader(zipfile.ZipFile):
+
+    def __init__(self, *args, **kwargs):
+        zipfile.ZipFile.__init__(self, *args, **kwargs)
+        if len(self.namelist()) != 1:
+            raise ValueError("Zip-compressed fixtures must contain one file.")
+
+    def read(self):
+        return zipfile.ZipFile.read(self, self.namelist()[0])
+
+
+def humanize(dirname):
+    return "'%s'" % dirname if dirname else 'absolute path'

tests/fixtures_regress/tests.py

@@ -450,7 +450,7 @@ class TestFixtures(TestCase):
                 commit=False,
                 stdout=stdout_output,
             )
-        self.assertTrue("No xml fixture 'this_fixture_doesnt_exist' in" in
+        self.assertTrue("No fixture 'this_fixture_doesnt_exist' in" in
             force_text(stdout_output.getvalue()))