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
{
    id: "org.example.sudobot.extension.hello" /* Extension ID */,
    main: "index.js" /* The entry point file name. */,
    src_main: "index.ts" /* The entry point file name. */,
    commands: "commands" /* Commands directory. The bot will load commands from this directory. */,
    events: "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. */,
    src_directory: "./src" /* The source directory where the source file of 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
{
    id: "org.example.sudobot.extension.hello",
    main: "index.js",
    src_main: "index.ts",
    commands: "commands",
    events: "events",
    language: "typescript",
    main_directory: "./build",
    src_directory: "./src",
    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 a `tsconfig.node.json` file which contains the configuration for the TypeScript compiler.

Now open up `tsconfig.node.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.
After this, create a symbolic link named `tsconfig.json` that points to `tsconfig.node.json`. On windows, just copy the file. The command to create the symbolic link
on a Unix/Linux based system would be the following:

```bash
ln -s ./tsconfig.node.json ./tsconfig.json
```

<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
```

**Please note that if you're using Bun to run the bot, the extensions will need to be configured differently. We'll include the instructions on how to do it
manually and also how you can automate it, very soon.**

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	id: "org.example.sudobot.extension.hello" /* Extension ID */,
39	main: "index.js" /* The entry point file name. */,
40	src_main: "index.ts" /* The entry point file name. */,
41	commands: "commands" /* Commands directory. The bot will load commands from this directory. */,
42	events: "events" /* Event handlers directory. The bot will load event handlers from this directory. */,
43	language: "typescript" /* The language being used for this extension. Can be either "javascript" or "typescript". */,
44	main_directory: "./build" /* The main directory where the entry point is located. */,
45	src_directory: "./src" /* The source directory where the source file of the entry point is located. */,
46	build_command: "npm run build" /* Command to build the extension. In this case `npm run build` invokes `tsc`. */,
47	}
48	```
49
50	## Creating your first SudoBot extension
51
52	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".
53
54	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:
55
56	```
57	+ sudobot/ [project root]
58	+ installed_extensions/
59	+ hello/
60	+ src/
61	+ commands/
62	+ events/
63	- extension.json
64	```
65
66	Now add the following to your `extension.json` file:
67
68	```json
69	{
70	id: "org.example.sudobot.extension.hello",
71	main: "index.js",
72	src_main: "index.ts",
73	commands: "commands",
74	events: "events",
75	language: "typescript",
76	main_directory: "./build",
77	src_directory: "./src",
78	build_command: "npm run build"
79	}
80	```
81
82	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).
83
84	#### Setting up TypeScript and Dependencies
85
86	First, run `npm init` to initialize your extension project. This will ask you a few questions and create a `package.json` file. Then run:
87
88	```bash
89	npm install --save ../.. # Path to the sudobot project root
90	```
91
92	<Callout type="info">
93	Remember this is a really important step to make sure your extension can
94	access SudoBot's core utilities to initialize itself. If you don't link
95	SudoBot with your extension, it will fail to import the necessary files.
96	</Callout>
97
98	Then we can go ahead and install the dependencies and also set up TypeScript.
99
100	```shell
101	npm install module-alias
102	npm install -D typescript @types/node
103	npx tsc --init
104	```
105
106	This will add `typescript` as a dev dependency and also create a `tsconfig.node.json` file which contains the configuration for the TypeScript compiler.
107
108	Now open up `tsconfig.node.json` file, and add the following (you can tweak these options if you want):
109
110	```json
111	{
112	"compilerOptions": {
113	"target": "ES2021",
114	"module": "commonjs",
115	"rootDir": "./src",
116	"baseUrl": "./",
117	"paths": {
118	"@sudobot/": ["node_modules/sudobot/build/out/main/typescript/"],
119	"@framework/*": [
120	"node_modules/sudobot/build/out/framework/typescript/*"
121	]
122	},
123	"resolveJsonModule": true,
124	"outDir": "./build",
125	"newLine": "lf",
126	"noEmitHelpers": true,
127	"noEmitOnError": true,
128	"allowSyntheticDefaultImports": true,
129	"esModuleInterop": true,
130	"forceConsistentCasingInFileNames": true,
131	"strict": true,
132	"skipLibCheck": true
133	},
134	"exclude": ["./tests", "./build"]
135	}
136	```
137
138	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.
139	After this, create a symbolic link named `tsconfig.json` that points to `tsconfig.node.json`. On windows, just copy the file. The command to create the symbolic link
140	on a Unix/Linux based system would be the following:
141
142	```bash
143	ln -s ./tsconfig.node.json ./tsconfig.json
144	```
145
146	<Callout type="info">
147	Remember to build the bot beforehand! As you can see, this alias points to
148	the `build` directory which is created when you build the bot.
149	</Callout>
150
151	Then open up `package.json` file and add the following inside the root object:
152
153	```json
154	"_moduleAliases": {
155	"@framework": "node_modules/sudobot/build/out/framework/typescript",
156	"@sudobot": "node_modules/sudobot/build/out/main/typescript"
157	},
158	"scripts": {
159	"build": "tsc"
160	}
161	```
162
163	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.
164
165	#### The entry point
166
167	We need to create the entry point now! Make a file `src/index.ts` and put the following code inside of that file:
168
169	```typescript
170	import "module-alias/register";
171	import { Extension } from "@sudobot/core/Extension";
172
173	class HelloExtension extends Extension {
174	// ...
175	}
176
177	export default HelloExtension;
178	```
179
180	That's actually all we need inside this file.
181
182	#### Adding commands to the extension
183
184	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:
185
186	```typescript
187	import { Command, type CommandMessage } from "@framework/commands/Command";
188	import type Context from "@framework/commands/Context";
189
190	class HelloCommand extends Command {
191	public override readonly name = "hello";
192	public override readonly description = "A simple hello-world command.";
193
194	public override async execute(context: Context<CommandMessage>) {
195	await context.reply("Hello world, from the hello extension!");
196	}
197	}
198
199	export default HelloCommand;
200	```
201
202	This command just responds to the user with "Hello world, from the hello extension!".
203
204	#### Adding event listeners to the extension
205
206	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:
207
208	```typescript
209	import EventListener from "@framework/events/EventListener";
210	import { Events } from "@framework/types/ClientEvents";
211	import type { Message } from "discord.js";
212
213	class MessageCreateEventListener extends EventListener<Events.MessageCreate> {
214	public override readonly name = Events.MessageCreate;
215
216	public override async execute(message: Message<boolean>): Promise<void> {
217	if (message.author.bot) {
218	return;
219	}
220
221	if (message.content === "ping") {
222	await message.reply("Pong, from the hello extension!");
223	}
224	}
225	}
226
227	export default MessageCreateEventListener;
228	```
229
230	This event listener listens to `MessageCreate` event, and whenever someone sends a message with content "ping", it will reply to them.
231
232	#### Building the extension
233
234	Building your newly created extension involves the same procedures as any other TypeScript project.
235	Install the dependencies and run the TypeScript compiler from the extension's directory (installed_extensions/hello):
236
237	```bash
238	npm install -D
239	npm run build
240	```
241
242	If using [Bun](https://bun.sh):
243
244	```bash
245	bun install -D
246	bun run build
247	```
248
249	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):
250
251	```bash
252	npm start
253	```
254
255	**Please note that if you're using Bun to run the bot, the extensions will need to be configured differently. We'll include the instructions on how to do it
256	manually and also how you can automate it, very soon.**
257
258	And then if everything was configured correctly, the `hello` command will be loaded and can be executed on any server.
259
260	Congratulations, you've just built an extension for SudoBot!
261
262	### Help and Support
263
264	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).