extensions/creating-extensions-for-v9/page.mdx

---
title: Creating Extensions for SudoBot v9
short_name: Creating Extensions for SudoBot v9
---

import Callout from "@/components/Alerts/Callout";

# Creating Extensions for SudoBot v9

SudoBot has support for extensions, and it was introduced in version 6.17. Extensions can extend the bot's feature, by adding commands, event listeners, services and a lot more stuff. You can install/uninstall/disable extensions, or create your own to make the bot behave exactly how you want. Extensions can be written using JavaScript and TypeScript.

In this article, you'll learn how SudoBot's extension system works.

## The extensions directory

To start using extensions, you need to create a root directory where extensions will be installed.
In this guide, we'll name the directory `installed_extensions/`. To create a directory named `installed_extensions/` in the main project root, run the following:

```bash
mkdir installed_extensions
```

Every installed extension goes inside this directory.

Now to tell SudoBot where to look for extensions, add the `EXTENSIONS_DIRECTORY` environment variable to your `.env` file:

```bash
# Path to the extensions root directory
EXTENSIONS_DIRECTORY=/example/path/to/extensions/directory
```

Each installed extension has a directory associated with it inside the `installed_extensions/` directory. Inside of that inner directory, there is a special file `extension.json` which contains meta information about the extension, and how to build it.

The `extension.json` file looks something like this:

```json5
{
    main: "./build/index.js" /* The entry point. */,
    commands: "./build/commands" /* Commands directory. The bot will load commands from this directory. */,
    events: "./build/events" /* Event handlers directory. The bot will load event handlers from this directory. */,
    language: "typescript" /* The language being used for this extension. Can be either "javascript" or "typescript". */,
    main_directory: "./build" /* The main directory where the entry point is located. */,
    build_command: "npm run build" /* Command to build the extension. In this case `npm run build` invokes `tsc`. */,
}
```

## Creating your first SudoBot extension

To get started, first create a directory named `installed_extensions` inside the project root. In that directory, create another directory for your extension. The name of this directory usually should be your extension's name. In this example, we'll name the extension "hello".

Then inside your extension's directory, create the `extension.json` file, and the `src/` directory. Inside `src`, create `events` and `commands` directories. The final directory tree should look something like this:

```
+ sudobot/ [project root]
  + installed_extensions/
    + hello/
      + src/
        + commands/
        + events/
      - extension.json
```

Now add the following to your `extension.json` file:

```json
{
    "main": "./build/index.js",
    "commands": "./build/commands",
    "events": "./build/events",
    "language": "typescript",
    "main_directory": "./build",
    "build_command": "npm run build"
}
```

We'll be using TypeScript to write the extension in this example. If you'd like to use JavaScript instead, you can set `language` to `javascript` and you don't need to specify a build command, and your main directory will be the directory where you put your JavaScript files (usually `src/`). You should also adjust the paths to point to that directory (rather than `build/` which is used in this example).

#### Setting up TypeScript and Dependencies

First, run `npm init` to initialize your extension project. This will ask you a few questions and create a `package.json` file. Then run:

```bash
npm install --save ../.. # Path to the sudobot project root
```

<Callout type="info">
    Remember **this is a really important step** to make sure your extension can
    access SudoBot's core utilities to initialize itself. If you don't link
    SudoBot with your extension, it will fail to import the necessary files.
</Callout>

Then we can go ahead and install the dependencies and also set up TypeScript.

```shell
npm install module-alias
npm install -D typescript @types/node
npx tsc --init
```

This will add `typescript` as a dev dependency and also create the `tsconfig.json` file which contains the configuration for the TypeScript compiler.

Now open up `tsconfig.json` file, and add the following (you can tweak these options if you want):

```json
{
    "compilerOptions": {
        "target": "ES2021",
        "module": "commonjs",
        "rootDir": "./src",
        "baseUrl": "./",
        "paths": {
            "@sudobot/*": ["node_modules/sudobot/build/out/main/typescript/*"],
            "@framework/*": [
                "node_modules/sudobot/build/out/framework/typescript/*"
            ]
        },
        "resolveJsonModule": true,
        "outDir": "./build",
        "newLine": "lf",
        "noEmitHelpers": true,
        "noEmitOnError": true,
        "allowSyntheticDefaultImports": true,
        "esModuleInterop": true,
        "forceConsistentCasingInFileNames": true,
        "strict": true,
        "skipLibCheck": true
    },
    "exclude": ["./tests", "./build"]
}
```

This sets up the `@sudobot` and `@framework` import aliases for TypeScript, specifies the source root and build directory, and a few other things that are needed.

<Callout type="info">
    Remember to build the bot beforehand! As you can see, this alias points to
    the `build` directory which is created when you build the bot.
</Callout>

Then open up `package.json` file and add the following inside the root object:

```json
"_moduleAliases": {
    "@framework": "node_modules/sudobot/build/out/framework/typescript",
    "@sudobot": "node_modules/sudobot/build/out/main/typescript"
},
"scripts": {
    "build": "tsc"
}
```

You might be thinking, why do we need to add the module aliases twice? It's because TypeScript doesn't actually deal with these module aliases, it just checks the types and imports. In runtime, we need another way to resolve these imports. We use `module-alias` for that.

#### The entry point

We need to create the entry point now! Make a file `src/index.ts` and put the following code inside of that file:

```typescript
import "module-alias/register";
import { Extension } from "@sudobot/core/Extension";

class HelloExtension extends Extension {
    // ...
}

export default HelloExtension;
```

That's actually all we need inside this file.

#### Adding commands to the extension

Alright, let's add a command to the extension! Create a file `src/commands/HelloCommand.ts` and inside of that file, put the following code:

```typescript
import { Command, type CommandMessage } from "@framework/commands/Command";
import type Context from "@framework/commands/Context";

class HelloCommand extends Command {
    public override readonly name = "hello";
    public override readonly description = "A simple hello-world command.";

    public override async execute(context: Context<CommandMessage>) {
        await context.reply("Hello world, from the hello extension!");
    }
}

export default HelloCommand;
```

This command just responds to the user with "Hello world, from the hello extension!".

#### Adding event listeners to the extension

Now, let's add an event listener to the extension! Create a file `src/events/MessageCreateEventListener.ts` and inside of that file, put the following code:

```typescript
import EventListener from "@framework/events/EventListener";
import { Events } from "@framework/types/ClientEvents";
import type { Message } from "discord.js";

class MessageCreateEventListener extends EventListener<Events.MessageCreate> {
    public override readonly name = Events.MessageCreate;

    public override async execute(message: Message<boolean>): Promise<void> {
        if (message.author.bot) {
            return;
        }

        if (message.content === "ping") {
            await message.reply("Pong, from the hello extension!");
        }
    }
}

export default MessageCreateEventListener;
```

This event listener listens to `MessageCreate` event, and whenever someone sends a message with content "ping", it will reply to them.

#### Building the extension

Building your newly created extension involves the same procedures as any other TypeScript project.
Install the dependencies and run the TypeScript compiler from the extension's directory (installed_extensions/hello):

```bash
npm install -D
npm run build
```

If using [Bun](https://bun.sh):

```bash
bun install -D
bun run build
```

This will take a little bit time. After that, you're ready to go. You can now start the bot from the main project root (assuming you've built it already):

```bash
npm start
```

Or using Bun (no build step required):

```bash
bun dev
```

And then if everything was configured correctly, the `hello` command will be loaded and can be executed on any server.

Congratulations, you've just built an extension for SudoBot!

### Help and Support

If you need help with anything, feel free to create a discussion topic at the [GitHub repo](https://github.com/onesoft-sudo/sudobot). You can also contact via email at [[email protected]](mailto:[email protected]), or join our [Discord Server](https://discord.gg/892GWhTzgs).
1	---
2	title: Creating Extensions for SudoBot v9
3	short_name: Creating Extensions for SudoBot v9
4	---
5
6	import Callout from "@/components/Alerts/Callout";
7
8	# Creating Extensions for SudoBot v9
9
10	SudoBot has support for extensions, and it was introduced in version 6.17. Extensions can extend the bot's feature, by adding commands, event listeners, services and a lot more stuff. You can install/uninstall/disable extensions, or create your own to make the bot behave exactly how you want. Extensions can be written using JavaScript and TypeScript.
11
12	In this article, you'll learn how SudoBot's extension system works.
13
14	## The extensions directory
15
16	To start using extensions, you need to create a root directory where extensions will be installed.
17	In this guide, we'll name the directory `installed_extensions/`. To create a directory named `installed_extensions/` in the main project root, run the following:
18
19	```bash
20	mkdir installed_extensions
21	```
22
23	Every installed extension goes inside this directory.
24
25	Now to tell SudoBot where to look for extensions, add the `EXTENSIONS_DIRECTORY` environment variable to your `.env` file:
26
27	```bash
28	# Path to the extensions root directory
29	EXTENSIONS_DIRECTORY=/example/path/to/extensions/directory
30	```
31
32	Each installed extension has a directory associated with it inside the `installed_extensions/` directory. Inside of that inner directory, there is a special file `extension.json` which contains meta information about the extension, and how to build it.
33
34	The `extension.json` file looks something like this:
35
36	```json5
37	{
38	main: "./build/index.js" /* The entry point. */,
39	commands: "./build/commands" /* Commands directory. The bot will load commands from this directory. */,
40	events: "./build/events" /* Event handlers directory. The bot will load event handlers from this directory. */,
41	language: "typescript" /* The language being used for this extension. Can be either "javascript" or "typescript". */,
42	main_directory: "./build" /* The main directory where the entry point is located. */,
43	build_command: "npm run build" /* Command to build the extension. In this case `npm run build` invokes `tsc`. */,
44	}
45	```
46
47	## Creating your first SudoBot extension
48
49	To get started, first create a directory named `installed_extensions` inside the project root. In that directory, create another directory for your extension. The name of this directory usually should be your extension's name. In this example, we'll name the extension "hello".
50
51	Then inside your extension's directory, create the `extension.json` file, and the `src/` directory. Inside `src`, create `events` and `commands` directories. The final directory tree should look something like this:
52
53	```
54	+ sudobot/ [project root]
55	+ installed_extensions/
56	+ hello/
57	+ src/
58	+ commands/
59	+ events/
60	- extension.json
61	```
62
63	Now add the following to your `extension.json` file:
64
65	```json
66	{
67	"main": "./build/index.js",
68	"commands": "./build/commands",
69	"events": "./build/events",
70	"language": "typescript",
71	"main_directory": "./build",
72	"build_command": "npm run build"
73	}
74	```
75
76	We'll be using TypeScript to write the extension in this example. If you'd like to use JavaScript instead, you can set `language` to `javascript` and you don't need to specify a build command, and your main directory will be the directory where you put your JavaScript files (usually `src/`). You should also adjust the paths to point to that directory (rather than `build/` which is used in this example).
77
78	#### Setting up TypeScript and Dependencies
79
80	First, run `npm init` to initialize your extension project. This will ask you a few questions and create a `package.json` file. Then run:
81
82	```bash
83	npm install --save ../.. # Path to the sudobot project root
84	```
85
86	<Callout type="info">
87	Remember this is a really important step to make sure your extension can
88	access SudoBot's core utilities to initialize itself. If you don't link
89	SudoBot with your extension, it will fail to import the necessary files.
90	</Callout>
91
92	Then we can go ahead and install the dependencies and also set up TypeScript.
93
94	```shell
95	npm install module-alias
96	npm install -D typescript @types/node
97	npx tsc --init
98	```
99
100	This will add `typescript` as a dev dependency and also create the `tsconfig.json` file which contains the configuration for the TypeScript compiler.
101
102	Now open up `tsconfig.json` file, and add the following (you can tweak these options if you want):
103
104	```json
105	{
106	"compilerOptions": {
107	"target": "ES2021",
108	"module": "commonjs",
109	"rootDir": "./src",
110	"baseUrl": "./",
111	"paths": {
112	"@sudobot/": ["node_modules/sudobot/build/out/main/typescript/"],
113	"@framework/*": [
114	"node_modules/sudobot/build/out/framework/typescript/*"
115	]
116	},
117	"resolveJsonModule": true,
118	"outDir": "./build",
119	"newLine": "lf",
120	"noEmitHelpers": true,
121	"noEmitOnError": true,
122	"allowSyntheticDefaultImports": true,
123	"esModuleInterop": true,
124	"forceConsistentCasingInFileNames": true,
125	"strict": true,
126	"skipLibCheck": true
127	},
128	"exclude": ["./tests", "./build"]
129	}
130	```
131
132	This sets up the `@sudobot` and `@framework` import aliases for TypeScript, specifies the source root and build directory, and a few other things that are needed.
133
134	<Callout type="info">
135	Remember to build the bot beforehand! As you can see, this alias points to
136	the `build` directory which is created when you build the bot.
137	</Callout>
138
139	Then open up `package.json` file and add the following inside the root object:
140
141	```json
142	"_moduleAliases": {
143	"@framework": "node_modules/sudobot/build/out/framework/typescript",
144	"@sudobot": "node_modules/sudobot/build/out/main/typescript"
145	},
146	"scripts": {
147	"build": "tsc"
148	}
149	```
150
151	You might be thinking, why do we need to add the module aliases twice? It's because TypeScript doesn't actually deal with these module aliases, it just checks the types and imports. In runtime, we need another way to resolve these imports. We use `module-alias` for that.
152
153	#### The entry point
154
155	We need to create the entry point now! Make a file `src/index.ts` and put the following code inside of that file:
156
157	```typescript
158	import "module-alias/register";
159	import { Extension } from "@sudobot/core/Extension";
160
161	class HelloExtension extends Extension {
162	// ...
163	}
164
165	export default HelloExtension;
166	```
167
168	That's actually all we need inside this file.
169
170	#### Adding commands to the extension
171
172	Alright, let's add a command to the extension! Create a file `src/commands/HelloCommand.ts` and inside of that file, put the following code:
173
174	```typescript
175	import { Command, type CommandMessage } from "@framework/commands/Command";
176	import type Context from "@framework/commands/Context";
177
178	class HelloCommand extends Command {
179	public override readonly name = "hello";
180	public override readonly description = "A simple hello-world command.";
181
182	public override async execute(context: Context<CommandMessage>) {
183	await context.reply("Hello world, from the hello extension!");
184	}
185	}
186
187	export default HelloCommand;
188	```
189
190	This command just responds to the user with "Hello world, from the hello extension!".
191
192	#### Adding event listeners to the extension
193
194	Now, let's add an event listener to the extension! Create a file `src/events/MessageCreateEventListener.ts` and inside of that file, put the following code:
195
196	```typescript
197	import EventListener from "@framework/events/EventListener";
198	import { Events } from "@framework/types/ClientEvents";
199	import type { Message } from "discord.js";
200
201	class MessageCreateEventListener extends EventListener<Events.MessageCreate> {
202	public override readonly name = Events.MessageCreate;
203
204	public override async execute(message: Message<boolean>): Promise<void> {
205	if (message.author.bot) {
206	return;
207	}
208
209	if (message.content === "ping") {
210	await message.reply("Pong, from the hello extension!");
211	}
212	}
213	}
214
215	export default MessageCreateEventListener;
216	```
217
218	This event listener listens to `MessageCreate` event, and whenever someone sends a message with content "ping", it will reply to them.
219
220	#### Building the extension
221
222	Building your newly created extension involves the same procedures as any other TypeScript project.
223	Install the dependencies and run the TypeScript compiler from the extension's directory (installed_extensions/hello):
224
225	```bash
226	npm install -D
227	npm run build
228	```
229
230	If using [Bun](https://bun.sh):
231
232	```bash
233	bun install -D
234	bun run build
235	```
236
237	This will take a little bit time. After that, you're ready to go. You can now start the bot from the main project root (assuming you've built it already):
238
239	```bash
240	npm start
241	```
242
243	Or using Bun (no build step required):
244
245	```bash
246	bun dev
247	```
248
249	And then if everything was configured correctly, the `hello` command will be loaded and can be executed on any server.
250
251	Congratulations, you've just built an extension for SudoBot!
252
253	### Help and Support
254
255	If you need help with anything, feel free to create a discussion topic at the [GitHub repo](https://github.com/onesoft-sudo/sudobot). You can also contact via email at [[email protected]](mailto:[email protected]), or join our [Discord Server](https://discord.gg/892GWhTzgs).