Unable to load the SpatiaLite library extension "/usr/local/lib/libspatialite.dylib"

[Kenial Sookyum Lee]

Installing libspatialite package with Homebrew on OS X and using django.contrib.gis.db.backends.spatialite as a database backend, I met this exception:

Traceback (most recent call last):
  File "manage.py", line 14, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/core/management/__init__.py", line 385, in execute_from_command_line
    utility.execute()
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/core/management/__init__.py", line 377, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/core/management/base.py", line 288, in run_from_argv
    self.execute(*args, **options.__dict__)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/core/management/base.py", line 338, in execute
    output = self.handle(*args, **options)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 63, in handle
    executor = MigrationExecutor(connection, self.migration_progress_callback)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/migrations/executor.py", line 17, in __init__
    self.loader = MigrationLoader(self.connection)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/migrations/loader.py", line 48, in __init__
    self.build_graph()
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/migrations/loader.py", line 179, in build_graph
    self.applied_migrations = recorder.applied_migrations()
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/migrations/recorder.py", line 59, in applied_migrations
    self.ensure_schema()
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/migrations/recorder.py", line 49, in ensure_schema
    if self.Migration._meta.db_table in self.connection.introspection.get_table_list(self.connection.cursor()):
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/backends/__init__.py", line 165, in cursor
    cursor = self.make_debug_cursor(self._cursor())
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/backends/__init__.py", line 138, in _cursor
    self.ensure_connection()
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/backends/__init__.py", line 133, in ensure_connection
    self.connect()
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/backends/__init__.py", line 122, in connect
    self.connection = self.get_new_connection(conn_params)
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/contrib/gis/db/backends/spatialite/base.py", line 65, in get_new_connection
    six.reraise(ImproperlyConfigured, ImproperlyConfigured(new_msg), sys.exc_info()[2])
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/contrib/gis/db/backends/spatialite/base.py", line 60, in get_new_connection
    cur.execute("SELECT load_extension(%s)", (self.spatialite_lib,))
  File "/Users/kenial/.virtualenvs/fp/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 485, in execute
    return Database.Cursor.execute(self, query, params)
django.core.exceptions.ImproperlyConfigured: Unable to load the SpatiaLite library extension "/usr/local/lib/libspatialite.dylib" because: dlsym(0x7f8bf32f8000, sqlite3_spatialite_init): symbol not found

On Homebrew's SpatiaLite 4.2.0 package what I've got, it provides both libspatialite.7.dylib and mod_spatialite.7.dylib. For its proper working, sqlite3 should load mod_spatialite instead of libspatialite, but it seems not detecting right package with ctypes.util.find_library('spatialite'). In case using find_library('mod_spatialite'), it does work.

I think it might be a problem of entry point, however, the sqlite3_spatialite_init symbol is in mod_spatialite.7.dylib at least, for it works.

p.s: For sure, you can avoid this by declaring sptialite library path manually in settings.py, like as:

SPATIALITE_LIBRARY_PATH='/usr/local/lib/mod_spatialite.dylib'

[Kenial Sookyum Lee]

patch of Ticket #23901