给Python中的MySQLdb模块添加超时功能的教程
使用Python操作MySQL数据库的时候常使用MySQLdb这个模块。
今天在开发的过程发现MySQLdb.connect有些参数没法设置。通过这个页面我们可以看到在connect的时候，可以设置的option和client_flags和MySQL c api相比差不少。
一个很重要的参数 MYSQL_OPT_READ_TIMEOUT没法设置，这个参数如果不设置，极致状况MySQL处于hang住，自动切换IP漂移，客户端无法重连到新MySQL。
给MySQLdb加Option很简单，只要修改_mysql.c这个把Python对象映射到MySQL操作的文件，添加参数，再加一段mysql_option即可。
下面是修改后的git diff 文件
?View Code BASH
diff --git a/_mysql.c b/_mysql.c
index d42cc54..61a9b34 100644
--- a/_mysql.c
+++ b/_mysql.c
@@ -489,9 +489,10 @@ _mysql_ConnectionObject_Initialize(
"named_pipe", "init_command",
"read_default_file", "read_default_group",
"client_flag", "ssl",
- "local_infile",
+ "local_infile", "read_timeout",
NULL } ;
int connect_timeout = 0;
+ int read_timeout = 0;
int compress = -1, named_pipe = -1, local_infile = -1;
char *init_command=NULL,
*read_default_file=NULL,
@@ -500,7 +501,7 @@ _mysql_ConnectionObject_Initialize(
self->converter = NULL;
self->open = 0;
check_server_init(-1);
- if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|ssssisOiiisssiOi:connect",
+ if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|ssssisOiiisssiOii:connect",
kwlist,
&host, &user, &passwd, &db,
&port, &unix_socket, &conv,
@@ -509,7 +510,8 @@ _mysql_ConnectionObject_Initialize(
&init_command, &read_default_file,
&read_default_group,
&client_flag, &ssl,
- &local_infile /* DO NOT PATCH FOR RECONNECT, IDIOTS
+ &local_infile, &read_timeout
+ /* DO NOT PATCH FOR RECONNECT, IDIOTS
IF YOU DO THIS, I WILL NOT SUPPORT YOUR PACKAGES. */
))
return -1;
@@ -540,6 +542,12 @@ _mysql_ConnectionObject_Initialize(
mysql_options(&(self->connection), MYSQL_OPT_CONNECT_TIMEOUT,
(char *)&timeout);
}
+
+ if (read_timeout) {
+ unsigned int timeout = read_timeout;
+ mysql_options(&(self->connection), MYSQL_OPT_READ_TIMEOUT, (char *)&timeout);
+ }
+
if (compress != -1) {
mysql_options(&(self->connection), MYSQL_OPT_COMPRESS, 0);
client_flag |= CLIENT_COMPRESS;
代码修改完毕，python setup.py install 即可，如果出现mysql_config找不到的问题。你还要修改setup_posix.py文件。
hoterran@hoterran-laptop:~/Projects/MySQL-python-1.2.3$ git diff setup_posix.py
diff --git a/setup_posix.py b/setup_posix.py
index 86432f5..f4f08f1 100644
--- a/setup_posix.py
+++ b/setup_posix.py
@@ -23,7 +23,7 @@ def mysql_config(what):
if ret/256 > 1:
raise EnvironmentError("%s not found" % (mysql_config.path,))
return data
-mysql_config.path = "mysql_config"
+mysql_config.path = "/usr/local/mysql/bin/mysql_config"
def get_config():
import os, sys
编译通过，我们来试试添加的read_timeout这个参数。
conn = MySQLdb.connect(host = DB_SERVER,user = DB_USERNAME,passwd = DB_PASSWORD,db = DB_NAME, port=int(DB_PORT), client_flag = 2, read_timeout = 10)
然后执行语句前，你试着把mysql用gdb hang住10s后，python就会异常抛错
OperationalError: (2013, 'Lost connection to MySQL server during query') >/home/hoterran/Projects/dbaas/trunk/dbtest.py(18)() >mydb.execute_sql(conn, sql) (Pdb) --Return-- > /home/hoterran/Projects/dbaas/trunk/dbtest.py(18)()->None > mydb.execute_sql(conn, sql) (Pdb) OperationalError: (2013, 'Lost connection to MySQL server during query') > <string>(1)<module>()->None
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1386
52
PHP and Python: Code Examples and Comparison
Apr 15, 2025 am 12:07 AM
PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.
Python vs. JavaScript: Community, Libraries, and Resources
Apr 15, 2025 am 12:16 AM
Python and JavaScript have their own advantages and disadvantages in terms of community, libraries and resources. 1) The Python community is friendly and suitable for beginners, but the front-end development resources are not as rich as JavaScript. 2) Python is powerful in data science and machine learning libraries, while JavaScript is better in front-end development libraries and frameworks. 3) Both have rich learning resources, but Python is suitable for starting with official documents, while JavaScript is better with MDNWebDocs. The choice should be based on project needs and personal interests.
Detailed explanation of docker principle
Apr 14, 2025 pm 11:57 PM
Docker uses Linux kernel features to provide an efficient and isolated application running environment. Its working principle is as follows: 1. The mirror is used as a read-only template, which contains everything you need to run the application; 2. The Union File System (UnionFS) stacks multiple file systems, only storing the differences, saving space and speeding up; 3. The daemon manages the mirrors and containers, and the client uses them for interaction; 4. Namespaces and cgroups implement container isolation and resource limitations; 5. Multiple network modes support container interconnection. Only by understanding these core concepts can you better utilize Docker.
How to run programs in terminal vscode
Apr 15, 2025 pm 06:42 PM
In VS Code, you can run the program in the terminal through the following steps: Prepare the code and open the integrated terminal to ensure that the code directory is consistent with the terminal working directory. Select the run command according to the programming language (such as Python's python your_file_name.py) to check whether it runs successfully and resolve errors. Use the debugger to improve debugging efficiency.
What is vscode What is vscode for?
Apr 15, 2025 pm 06:45 PM
VS Code is the full name Visual Studio Code, which is a free and open source cross-platform code editor and development environment developed by Microsoft. It supports a wide range of programming languages and provides syntax highlighting, code automatic completion, code snippets and smart prompts to improve development efficiency. Through a rich extension ecosystem, users can add extensions to specific needs and languages, such as debuggers, code formatting tools, and Git integrations. VS Code also includes an intuitive debugger that helps quickly find and resolve bugs in your code.
Python: Automation, Scripting, and Task Management
Apr 16, 2025 am 12:14 AM
Python excels in automation, scripting, and task management. 1) Automation: File backup is realized through standard libraries such as os and shutil. 2) Script writing: Use the psutil library to monitor system resources. 3) Task management: Use the schedule library to schedule tasks. Python's ease of use and rich library support makes it the preferred tool in these areas.
Can vs code run in Windows 8
Apr 15, 2025 pm 07:24 PM
VS Code can run on Windows 8, but the experience may not be great. First make sure the system has been updated to the latest patch, then download the VS Code installation package that matches the system architecture and install it as prompted. After installation, be aware that some extensions may be incompatible with Windows 8 and need to look for alternative extensions or use newer Windows systems in a virtual machine. Install the necessary extensions to check whether they work properly. Although VS Code is feasible on Windows 8, it is recommended to upgrade to a newer Windows system for a better development experience and security.
Can visual studio code be used in python
Apr 15, 2025 pm 08:18 PM
VS Code can be used to write Python and provides many features that make it an ideal tool for developing Python applications. It allows users to: install Python extensions to get functions such as code completion, syntax highlighting, and debugging. Use the debugger to track code step by step, find and fix errors. Integrate Git for version control. Use code formatting tools to maintain code consistency. Use the Linting tool to spot potential problems ahead of time.
