MacOS Ventura下Django无法运行：GDAL加载libtiff版本错误

在MacOS Ventura系统上运行Django时遇到GDAL无法加载libtiff库的问题。

已确认系统中安装了libtiff：

% otool -L /opt/homebrew/lib/libgdal.dylib | grep libtiff
    /opt/homebrew/opt/libtiff/lib/libtiff.6.dylib (compatibility version 7.0.0, current version 7.1.0)

但错误信息显示，GDAL尝试加载libtiff.5.dylib，而当前安装的是libtiff.6.dylib。运行python manage.py runserver时的错误日志如下：

% python manage.py runserver 
Watching for file changes with StatReloader
2023-10-01 17:14:00,801 INFO Watching for file changes with StatReloader
Exception in thread django-main-thread:
Traceback (most recent call last):
  File "/opt/homebrew/Cellar/python@3.9/3.9.18/Frameworks/Python.framework/Versions/3.9/lib/python3.9/threading.py", line 980, in _bootstrap_inner
    self.run()
  File "/opt/homebrew/Cellar/python@3.9/3.9.18/Frameworks/Python.framework/Versions/3.9/lib/python3.9/threading.py", line 917, in run
    self._target(*self._args, **self._kwargs)
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/utils/autoreload.py", line 54, in wrapper
    fn(*args, **kwargs)
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/core/management/commands/runserver.py", line 109, in inner_run
    autoreload.raise_last_exception()
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/utils/autoreload.py", line 77, in raise_last_exception
    raise _exception[1]
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/core/management/__init__.py", line 337, in execute
    autoreload.check_errors(django.setup)()
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/utils/autoreload.py", line 54, in wrapper
    fn(*args, **kwargs)
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/__init__.py", line 24, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/apps/registry.py", line 91, in populate
    app_config = AppConfig.create(entry)
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/apps/config.py", line 90, in create
    module = import_module(entry)
  File "/opt/homebrew/Cellar/python@3.9/3.9.18/Frameworks/Python.framework/Versions/3.9/lib/python3.9/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1030, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 986, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 850, in exec_module
  File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/mapwidgets/__init__.py", line 4, in <module>
    from .widgets import GooglePointFieldWidget, GooglePointFieldInlineWidget, \
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/mapwidgets/widgets.py", line 5, in <module>
    from django.contrib.gis.forms import BaseGeometryWidget
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/forms/__init__.py", line 3, in <module>
    from .fields import (  # NOQA
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/forms/fields.py", line 2, in <module>
    from django.contrib.gis.gdal import GDALException
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/gdal/__init__.py", line 28, in <module>
    from django.contrib.gis.gdal.datasource import DataSource
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/gdal/datasource.py", line 39, in <module>
    from django.contrib.gis.gdal.driver import Driver
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/gdal/driver.py", line 5, in <module>
    from django.contrib.gis.gdal.prototypes import ds as vcapi, raster as rcapi
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/gdal/prototypes/ds.py", line 9, in <module>
    from django.contrib.gis.gdal.libgdal import GDAL_VERSION, lgdal
  File "/Users/myproj/Documents/project/projectdotcom/env_m1/lib/python3.9/site-packages/django/contrib/gis/gdal/libgdal.py", line 47, in <module>
    lgdal = CDLL(lib_path)
  File "/opt/homebrew/Cellar/python@3.9/3.9.18/Frameworks/Python.framework/Versions/3.9/lib/python3.9/ctypes/__init__.py", line 374, in __init__
    self._handle = _dlopen(self._name, mode)
OSError: dlopen(/opt/homebrew/lib/libgdal.dylib, 0x0006): Library not loaded: /opt/homebrew/opt/libtiff/lib/libtiff.5.dylib
  Referenced from: <3FEB9C56-E432-36C6-A940-FC254CC92FAB> /opt/homebrew/Cellar/libgeotiff/1.7.1_1/lib/libgeotiff.5.dylib
  Reason: tried: '/opt/homebrew/opt/libtiff/lib/libtiff.5.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/opt/homebrew/opt/libtiff/lib/libtiff.5.dylib' (no such file), '/opt/homebrew/opt/libtiff/lib/libtiff.5.dylib' (no such file), '/usr/local/lib/libtiff.5.dylib' (no such file), '/usr/lib/libtiff.5.dylib' (no such file, not in dyld cache), '/opt/homebrew/Cellar/libtiff/4.6.0/lib/libtiff.5.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/opt/homebrew/Cellar/libtiff/4.6.0/lib/libtiff.5.dylib' (no such file), '/opt/homebrew/Cellar/libtiff/4.6.0/lib/libtiff.5.dylib' (no such file), '/usr/local/lib/libtiff.5.dylib' (no such file), '/usr/lib/libtiff.5.dylib' (no such file, not in dyld cache)

从错误日志可知，并非GDAL直接依赖libtiff.5，而是libgeotiff依赖旧版本的libtiff。以下是几种可行的解决方法：

方法一：创建软链接兼容旧版本 #

直接在libtiff安装目录下创建指向新版本的软链接，让系统能找到libtiff.5.dylib：

sudo ln -s /opt/homebrew/opt/libtiff/lib/libtiff.6.dylib /opt/homebrew/opt/libtiff/lib/libtiff.5.dylib

创建完成后，重新运行python manage.py runserver测试是否正常。

方法二：重新编译libgeotiff适配新版本libtiff #

如果软链接方法出现兼容性问题，可重新编译libgeotiff，使其链接到当前的libtiff.6：

brew reinstall libgeotiff --build-from-source

等待编译完成后，再次启动Django服务。

方法三：安装指定版本的libtiff #

若上述方法均无效，可安装libtiff的5.x版本以匹配依赖：

brew install libtiff@5

安装完成后，需确保系统优先使用该版本，可通过设置环境变量：

export PATH="/opt/homebrew/opt/libtiff@5/bin:$PATH"
export LDFLAGS="-L/opt/homebrew/opt/libtiff@5/lib"
export CPPFLAGS="-I/opt/homebrew/opt/libtiff@5/include"

若需永久生效，可将这些环境变量添加到~/.zshrc或~/.bash_profile文件中。

内容的提问来源于stack exchange，提问作者Axil