Discuss the basic writing method of Golang plug-in

Go is an open source programming language that has been widely used in many fields. Among them, Golang’s scalability support has always attracted much attention. Golang's plug-in mechanism is also part of supporting its scalability. In this article, we will discuss the basics of writing Golang plugins.

1. Overview

Golang plugin is an executable binary file that can be loaded into a Golang application. It is loaded at runtime and can be unloaded dynamically without restarting the application. Using Golang plugins, we don't need to embed certain functionality into the application, we can develop and test it separately and then load them into the application.

2. Limitations of plug-ins

Although using Golang plug-ins can enhance the scalability of our code, there are also some restrictions that need to be followed. When developing Golang plug-ins, you need to pay attention to the following:

• The plug-in must be an executable binary file.
• Plug-ins must be compiled under the same operating system and architecture, that is, the plug-in and the main program must be compiled in the same environment.
• The -GO-PLUGIN option needs to be used when compiling the plug-in.
• The main program must explicitly import the symbols in the plug-in, otherwise the plug-in cannot be loaded.

3. How to write the plug-in

In the development process of Golang plug-in, we first need to create an executable binary file, which can be generated position-independently through the -fpic option code. Next compile using the -GO-PLUGIN option when compiling.

For example:

$ go build -buildmode=plugin -o my_plugin.so my_plugin.go

This command will generate an executable binary file named my_plugin.so. Now we can load it in the main program. When we load a plug-in, we need to let Golang know that we are loading a plug-in, which can accomplish this task through Go's plug-in package. Next, let's take a look at the code for loading the plug-in:

package main

import (
    "plugin"
)

func main() {
    p, err := plugin.Open("my_plugin.so")
    if err != nil {
        panic(err)
    }

    myPluginFunc, err := p.Lookup("MyPluginFunc")
    if err != nil {
        panic(err)
    }

    myPluginFunc.(func())()
}

In the above code, we open the plug-in through the plugin.Open function and use the p.Lookup function to find the symbol MyPluginFunc. Note that MyPluginFunc here is the exported function in the plug-in. After finding the function, we convert it to a func() instance and then call it as a plugin. This is a simple example that gives us an idea of ​​how to write and work with plugins.

4. Summary

This article discusses the basic writing method of Golang plug-in. Using Golang plug-ins can enhance the scalability of our code, but there are also some restrictions that need to be followed. When writing a plugin, we need to create a position-independent code and then compile it using the -GO-PLUGIN option when compiling. When loading a plug-in in the main program, we need to use the functions in Go's plug-in package to complete this task. One last thing to note is that plugins must be compiled under the same operating system and architecture.

The above is the detailed content of Discuss the basic writing method of Golang plug-in. For more information, please follow other related articles on the PHP Chinese website!