mac + python3 + django2.2 + mysql 遇到数据库连接包问题
Django用到了2.2版本， 开始搭建了新的服务， 出师未捷先采坑
到达数据库迁移的时候， 出现了错误
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module.
Did you install mysqlclient?这是一个很烦心的事情， 于是去搜索了一下
大致就是说，安装pymysql包
pip install pymysql然后在与想settings.py 同一文件夹的_init_.py中增加
import pymysql
pymysql.install_as_MySQLdb()增加完成了之后又出现了错误
File "/Users/lixiang/.env/lib/python3.6/site-packages/django/db/backends/mysql/base.py", line 36, in <module>
raise ImproperlyConfigured('mysqlclient 1.3.13 or newer is required; you have %s.' % Database.__version__)
django.core.exceptions.ImproperlyConfigured: mysqlclient 1.3.13 or newer is required; you have 0.9.3.说你的pymysql的版本是0.9.3， 同时需要mysqlclient需要1.3.13（记住这句话， 标记为 ”错误理解“），我有傻傻的去安装mysqlclient，
pip install mysqlclient==1.3.13结果还是原来的错误， 还是原来的懵逼
继续查， 有查到了解决方案
方案是去Django的包中改代码
路径是： /Users/lixiang/.env/lib/python3.6/site-packages/django/db/backends/mysql/base.py
把这行
if version < (1, 3, 13):
raise ImproperlyConfigured(
'mysqlclient 1.3.13 or newer is required; you have %s.'
% Database.__version__
)
改成这样, 也就是注释：
if version < (1, 3, 13):
pass
'''
raise ImproperlyConfigured(
'mysqlclient 1.3.13 or newer is required; you have %s.'
% Database.__version__
)
'''然后在改另一个文件
路径是： /Users/lixiang/.env/lib/python3.6/site-packages/django/db/backends/mysql/operations.py
把这行
query = query.decode(errors='replace')改成
query = query.encode(errors='replace')完美解决
(.env) ➜ cws python manage.py migrate
Operations to perform:
Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying admin.0003_logentry_add_action_flag_choices... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying auth.0002_alter_permission_name_max_length... OK
Applying auth.0003_alter_user_email_max_length... OK
Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying auth.0009_alter_user_last_name_max_length... OK
Applying auth.0010_alter_group_name_max_length... OK
Applying auth.0011_update_proxy_permissions... OK
Applying sessions.0001_initial... OK但是确实有点瑕疵
就是因为我在修改/Users/lixiang/.env/lib/python3.6/site-packages/django/db/backends/mysql/base.py文件是时候发现了这样一块
MySQL database backend for Django.
Requires mysqlclient: https://pypi.org/project/mysqlclient/显示django mysql数据后台， 需要mysqlclient包， 地址为
忽然有些明白了， Django后台需要的包是不是mysqlclient， 查查看
mysqlclient是python3的mysql版本， 这么一想pymysql我做的这些东西都是为了兼容， 上边理解错误的话， 其实是把pymsql的0.9.3版本 当成了mysqlclient版本
还是使用mysqlclient吧
上边mysqlclient的地址已经有很详细的安装说明了， 主要说一下mac上的安装， 需要先安装mysql-connector-c
brew install mysql-connector-c # macOS (Homebrew) (Currently, it has bug. See below)因为我已经装过了， 这里重装一下，为了掩饰（安装： brew install mysql-connector-c）
(.env) ➜ brew reinstall mysql-connector-c
==> Reinstalling mysql-connector-c
==> Downloading https://homebrew.bintray.com/bottles/mysql-connector-c-6.1.11.high_sierra.bottle.tar.
Already downloaded: /Users/lixiang/Library/Caches/Homebrew/downloads/c68782c842162dcb79a96dd6b880e906521be7595069066f870426f1de9aba35--mysql-connector-c-6.1.11.high_sierra.bottle.tar.gz
==> Pouring mysql-connector-c-6.1.11.high_sierra.bottle.tar.gz
/usr/local/Cellar/mysql-connector-c/6.1.11: 79 files, 15.3MB然后修改mysql_config
vim /usr/local/Cellar/mysql-connector-c/6.1.11/bin/mysql_config因为有bug， 需要将
# on macOS, on or about line 112:
# Create options
libs="-L$pkglibdir"
libs="$libs -l "改为
# Create options
libs="-L$pkglibdir"
libs="$libs -lmysqlclient -lssl -lcrypto"这个ssl也可能有问题， 下面链接可以解决
OSX ld: library not found for -lssl然后做一次link
(.env) ➜ brew link mysql-connector-c
Linking /usr/local/Cellar/mysql-connector-c/6.1.11... 48 symlinks created最后强制mysqlclient重新编译和安装：
pip install --force-reinstall --ignore-installed --no-binary :all: mysqlclient我本地安装mysql客户端， 使用的是docker， 可能你还有问题， 可以使用下面链接解决