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---
#https://www.notion.so/n8n/Frontmatter-432c2b8dff1f43d4b1c8d20075510fe4
contentType: explanation
---
# Choose your node building approach
n8n has two node-building styles, declarative and programmatic.
You should use the declarative style for most nodes. This style:
* Uses a JSON-based syntax, making it simpler to write, with less risk of introducing bugs.
* Is more future-proof.
* Supports integration with REST APIs.
The programmatic style is more verbose. You must use the programmatic style for:
* Trigger nodes
* Any node that isn't REST-based. This includes nodes that need to call a GraphQL API and nodes that use external dependencies.
* Any node that needs to transform incoming data.
* Full versioning. Refer to [Node versioning](/integrations/creating-nodes/build/reference/node-versioning.md) for more information on types of versioning.
## Data handling differences
The main difference between the declarative and programmatic styles is how they handle incoming data and build API requests. The programmatic style requires an `execute()` method, which reads incoming data and parameters, then builds a request. The declarative style handles this using the `routing` key in the `operations` object. Refer to [Node base file](/integrations/creating-nodes/build/reference/node-base-files/index.md) for more information on node parameters and the `execute()` method.
## Syntax differences
To understand the difference between the declarative and programmatic styles, compare the two code snippets below. This example creates a simplified version of the SendGrid integration, called "FriendGrid." The following code snippets aren't complete: they emphasize the differences in the node building styles.
In programmatic style:
```js
import {
IExecuteFunctions,
INodeExecutionData,
INodeType,
INodeTypeDescription,
IRequestOptions,
} from 'n8n-workflow';
// Create the FriendGrid class
export class FriendGrid implements INodeType {
description: INodeTypeDescription = {
displayName: 'FriendGrid',
name: 'friendGrid',
. . .
properties: [
{
displayName: 'Resource',
. . .
},
{
displayName: 'Operation',
name: 'operation',
type: 'options',
displayOptions: {
show: {
resource: [
'contact',
],
},
},
options: [
{
name: 'Create',
value: 'create',
description: 'Create a contact',
},
],
default: 'create',
description: 'The operation to perform.',
},
{
displayName: 'Email',
name: 'email',
. . .
},
{
displayName: 'Additional Fields',
// Sets up optional fields
},
],
};
async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
let responseData;
const resource = this.getNodeParameter('resource', 0) as string;
const operation = this.getNodeParameter('operation', 0) as string;
//Get credentials the user provided for this node
const credentials = await this.getCredentials('friendGridApi') as IDataObject;
if (resource === 'contact') {
if (operation === 'create') {
// Get email input
const email = this.getNodeParameter('email', 0) as string;
// Get additional fields input
const additionalFields = this.getNodeParameter('additionalFields', 0) as IDataObject;
const data: IDataObject = {
email,
};
Object.assign(data, additionalFields);
// Make HTTP request as defined in https://sendgrid.com/docs/api-reference/
const options: IRequestOptions = {
headers: {
'Accept': 'application/json',
'Authorization': `Bearer ${credentials.apiKey}`,
},
method: 'PUT',
body: {
contacts: [
data,
],
},
url: `https://api.sendgrid.com/v3/marketing/contacts`,
json: true,
};
responseData = await this.helpers.httpRequest(options);
}
}
// Map data to n8n data
return [this.helpers.returnJsonArray(responseData)];
}
}
```
In declarative style:
```js
import { INodeType, INodeTypeDescription } from 'n8n-workflow';
// Create the FriendGrid class
export class FriendGrid implements INodeType {
description: INodeTypeDescription = {
displayName: 'FriendGrid',
name: 'friendGrid',
. . .
// Set up the basic request configuration
requestDefaults: {
baseURL: 'https://api.sendgrid.com/v3/marketing'
},
properties: [
{
displayName: 'Resource',
. . .
},
{
displayName: 'Operation',
name: 'operation',
type: 'options',
displayOptions: {
show: {
resource: [
'contact',
],
},
},
options: [
{
name: 'Create',
value: 'create',
description: 'Create a contact',
// Add the routing object
routing: {
request: {
method: 'POST',
url: '=/contacts',
send: {
type: 'body',
properties: {
email: {{$parameter["email"]}}
}
}
}
},
// Handle the response to contact creation
output: {
postReceive: [
{
type: 'set',
properties: {
value: '={{ { "success": $response } }}'
}
}
]
}
},
],
default: 'create',
description: 'The operation to perform.',
},
{
displayName: 'Email',
. . .
},
{
displayName: 'Additional Fields',
// Sets up optional fields
},
],
}
// No execute method needed
}
```
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