form-handler.ts•3.5 kB
/**
* Form trigger handler
*
* Handles form-based workflow triggers:
* - POST to /form/<workflowId> or /form-test/<workflowId>
* - Passes form fields as request body
* - Workflow must be active (for production endpoint)
*/
import { z } from 'zod';
import axios, { AxiosRequestConfig } from 'axios';
import { Workflow, WebhookRequest } from '../../types/n8n-api';
import {
TriggerType,
TriggerResponse,
TriggerHandlerCapabilities,
DetectedTrigger,
FormTriggerInput,
} from '../types';
import { BaseTriggerHandler } from './base-handler';
/**
* Zod schema for form input validation
*/
const formInputSchema = z.object({
workflowId: z.string(),
triggerType: z.literal('form'),
formData: z.record(z.unknown()).optional(),
data: z.record(z.unknown()).optional(),
headers: z.record(z.string()).optional(),
timeout: z.number().optional(),
waitForResponse: z.boolean().optional(),
});
/**
* Form trigger handler
*/
export class FormHandler extends BaseTriggerHandler<FormTriggerInput> {
readonly triggerType: TriggerType = 'form';
readonly capabilities: TriggerHandlerCapabilities = {
requiresActiveWorkflow: true,
canPassInputData: true,
};
readonly inputSchema = formInputSchema;
async execute(
input: FormTriggerInput,
workflow: Workflow,
triggerInfo?: DetectedTrigger
): Promise<TriggerResponse> {
const startTime = Date.now();
try {
// Build form URL
const baseUrl = this.getBaseUrl();
if (!baseUrl) {
return this.errorResponse(input, 'Cannot determine n8n base URL', startTime);
}
// Form triggers use /form/<path> endpoint
// The path can be from trigger info or workflow ID
const formPath = triggerInfo?.node?.parameters?.path || input.workflowId;
const formUrl = `${baseUrl.replace(/\/+$/, '')}/form/${formPath}`;
// Merge formData and data (formData takes precedence)
const formFields = {
...input.data,
...input.formData,
};
// SSRF protection
const { SSRFProtection } = await import('../../utils/ssrf-protection');
const validation = await SSRFProtection.validateWebhookUrl(formUrl);
if (!validation.valid) {
return this.errorResponse(input, `SSRF protection: ${validation.reason}`, startTime);
}
// Build request config
const config: AxiosRequestConfig = {
method: 'POST',
url: formUrl,
headers: {
'Content-Type': 'application/json',
...input.headers,
},
data: formFields,
timeout: input.timeout || (input.waitForResponse !== false ? 120000 : 30000),
validateStatus: (status) => status < 500,
};
// Make the request
const response = await axios.request(config);
return this.normalizeResponse(response.data, input, startTime, {
status: response.status,
statusText: response.statusText,
metadata: {
duration: Date.now() - startTime,
},
});
} catch (error) {
const errorMessage = error instanceof Error ? error.message : 'Unknown error';
// Try to extract execution ID from error if available
const errorDetails = (error as any)?.response?.data;
const executionId = errorDetails?.executionId || errorDetails?.id;
return this.errorResponse(input, errorMessage, startTime, {
executionId,
code: (error as any)?.code,
details: errorDetails,
});
}
}
}