​

When to use actions?

Actions encapsulate one-off synchronous workflows that involve external APIs:

• write back information to an external API (e.g. update CRM contact field, ticket status)
• trigger external events in an external API (e.g. send email, Slack notification)
• fetch data synchronously from an external API (e.g. show a one-off list of user)

Actions let you benefit from the advantages of the Proxy, but allowing to encapsulate more complex logic (e.g. chained calls) in Nango scripts instead of in your code-base. With actions, you get:

• Credential-injection in requests
• Logging & monitoring
• Rate-limit handling
• Automated retries
• Pagination helpers
• Actions API

Actions can take in parameters and return data. They run synchronously, so you can use them for building your UI.

​

Step 1: Setup the Nango CLI & nango-integrations folder

Install the Nango CLI globally:

npm install -g nango

Your Nango actions live in your repo in a folder called nango-integrations. You can place this folder anywhere in your file tree, but we recommend you place it at the root level of your project.

In the folder where you want your integrations folder (e.g. root of your project), run:

nango init # Creates `./nango-integrations` with initial config

<YOUR-REPO>
    |
    nango-integrations
            |
            +- nango.yaml
            +- slack-notification-send.ts
            +- sendgrid-email-send.ts
            ...

Next, we need to authenticate the CLI. Add the following env vars (e.g. in an .env file in ./nango-integrations):

NANGO_SECRET_KEY_PROD='<prod-secret-key>'
NANGO_SECRET_KEY_DEV='<dev-secret-key>'

Get your prod and dev secret keys from the Project Settings tab (toggle between the prod and dev environment in the left nav bar).

​

Step 2: Create an action

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Configure your action in nango.yaml

Open the nango.yaml file inside the nango-integrations folder and inspect its field:

integrations:
	slack-dev: # Integration name (must match an integration name in the Integrations tab of your Nango dashboard).
		slack-alert: # Arbitrary (unique) action name
            type: action
			returns:
				- SlackAlertResponse # Data model (defined below) as returned by your action script

models: 
	SlackAlertResponse: # Data model referenced above
        ok: boolean

ExampleUser:
    project_id: string
    names: string[] # An array of strings
    number_of_cats: number
    completed: boolean
    emails:
        personal_email: string
        business_email: string | null
        other_emails: string[] | null
    created_at: date # Date is a full timestamp with both date & time
    modified_at: date

Nango uses the models you define in nango.yaml to provide type safety when:

• you write action scripts
• you trigger action scripts, passing in parameters and getting back a response

Multiple actions can take in the same parameters and return the same responses, which lets you easily create your own unified API with standard data models tailored to your needs.

​

Write your action

Modify the configuration of nango.yaml as you need and run (in ./nango-integrations):

nango generate

This will generate the scaffold for your action script(s). Open any action script (named [action-name].ts) which contains the following template (for the Slack example above):

import { NangoSync, SlackAlertResponse } from './models';

export default async function runAction(nango: NangoSync, input: any): Promise<SlackAlertResponse> {
	// Integration code goes here.
}

Action scripts let you arbitrarly interact with external APIs. This logic is defined by you so that you can build arbitrarily custom and complex integrations.

To develop actions locally and test them run the following within ./nango-integrations:

nango dev # Continuously watches integration files for changes.

Nango now watches your nango-integrations folder for changes and compiles the action scripts & data models as needed. If there are any compilation errors (e.g. due to type issues) you can see them in the terminal where nango dev runs.

Fill in the runAction method with your integration code:

import { NangoSync, SlackAlertResponse } from './models';

interface SlackAlertParams {
    channel: string
}

export default async function runAction(nango: NangoSync, input: SlackAlertParams): Promise<SlackAlertResponse> {
    const res = await nango.post({
        endpoint: '/api/chat.postMessage',
        params: {
            channel: input.channel,
            text: "Hello world :tada"
        }
    });

    return { ok: res.data.ok }
}

Action scripts are called programmatically from your codebase, run synchronously and return the data specified in the runAction function.

​

Dry run your action

Before you deploy your action to your cloud account you can test it locally to make sure it works as expected. You will probably use this a lot whilst developing your action.

Use the dryrun function of the CLI:

nango dryrun slack-alert test-connection-id --input '{"channel": "C02MPPQC8FK"}'

dryrun will print the data as returned.

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Step 3: Deploy an action

1. Deploy to the Dev environment

When your action script is ready, you can deploy it to your Dev environment in Nango:

nango deploy dev

Inspect the Syncs & Actions tab to verify the deployment succeeded.

2. Deploy to the Prod environment

Once you are ready to deploy to production, run:

nango deploy prod

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Step 4: Trigger an action

Actions are triggered explicitly and run synchronously, with the backend SDK or the REST API:

• Node SDK

• cURL

import { Nango }  from '@nangohq/node';
import type { SlackAlertResponse } from '<path-to-nango-integrations>/models'

const nango = new Nango({ secretKey: '<your-dev-secret-key>' });

const result: SlackAlertResponse = await nango.triggerAction({
    providerConfigKey: 'slack-dev',
    connectionId: 'test-connection-id',
    model: 'slack-alert',
    input: { channel: 'C02MPPQC8FK' }
});