Webhooks

See Webhooks for what a webhook is. Use eventStore.webhooks to register webhook observers for event streams.

Register a webhook programmatically

import 'reflect-metadata';
import { ChronicleClient, ChronicleOptions, eventType } from '@cratis/chronicle';
import { field } from '@cratis/fundamentals';

@eventType()
class EmployeeHired {
    @field(String) firstName: string;
    @field(String) lastName: string;

    constructor(firstName: string, lastName: string) {
        this.firstName = firstName;
        this.lastName = lastName;
    }
}

const client = new ChronicleClient(ChronicleOptions.development());
const eventStore = await client.getEventStore('MyStore');

await eventStore.webhooks.register(
    'employee-audit',
    'https://example.internal/webhooks/employee-audit',
    builder => {
        builder
            .withEventType(EmployeeHired)
            .withHeader('x-source', 'chronicle')
            .withBearerToken('token-value');
    }
);

client.dispose();

Define discoverable webhooks with decorators

The @webhook(...) decorator registers a webhook class for discovery:

• @webhook(targetUrl)
• @webhook(id, targetUrl)
• @webhook(id, targetUrl, eventSequenceId)

import 'reflect-metadata';
import { IWebhook, IWebhookDefinitionBuilder, webhook } from '@cratis/chronicle';

@webhook('employee-webhook', 'https://example.internal/webhooks/employees')
class EmployeeWebhook implements IWebhook {
    define(builder: IWebhookDefinitionBuilder): void {
        builder
            .notReplayable()
            .withHeader('x-client', 'chronicle-ts');
    }
}

getEventStore(...) registers every @webhook class whose module has been imported, together with the store’s other artifacts.

Chronicle sends events to the target URL from the kernel, so the URL must be reachable from the kernel, not only from your application. Use withBearerToken, withBasicAuth, or withOAuth rather than an unauthenticated endpoint, and keep the secrets in configuration.

API

eventStore.webhooks exposes:

• discover()
• registerDiscovered()
• register(webhookId, targetUrl, configure)
• getWebhooks()
• remove(webhookId)