Create a custom integration
Step-by-step guide on how to create a custom integration with Nango.
In Nango, integration use-cases are mapped to syncs and actions. Before starting, determine if a sync, an action, or a combination of both fits your use case.
Pre-requisite: set up an integrations folder (step-by-step guide).
Edit the nango.yaml configuration
In your nango-integrations folder, open the nango.yaml configuration file (reference).
Configure a sync
This example nango.yaml configuration describes a sync that continuously fetches contacts from Salesforce:
integrations:
salesforce: # Integration ID
syncs:
salesforce-contacts: # Sync name (must match integration script name)
description: |
Syncs contacts based on a field mapping object.
runs: every day # Sync frequency
output: Contact # Output model
endpoint: /crm/contact # Unified Nango endpoint (always GET for syncs)
scopes: offline_access,api # Necessary scopes
models:
Contact: # Data model reference above
id: string # Required unique ID
first_name: string
last_name: string
email: string
account_id: string
last_modified_date: string
Learn more about sync configurations in the reference and check out example templates.
Configure an action
This example nango.yaml configuration describes an action that synchronously fetches a contact by ID from Salesforce:
integrations:
salesforce: # Integration ID
actions:
salesforce-contact-fields: # Action name (must match integration script name)
description: Fetch available contact fields
output: ContactSchema # Output model
endpoint: /crm/contact-field # Unified Nango endpoint (defaults to POST for actions)
scopes: offline_access,api # Necessary scopes
models:
ContactSchema:
fields: string[]
Learn more about actions configurations in the reference and check out example templates.
Write an integration script
Generate the integration script scaffolding
Everytime that you modify the nango.yaml configuration, run:
nango generate # (in `./nango-integrations`)
Among other things, this will generate the integration script files with initial scaffolding for any sync or action that you added (existing integration script files stay untouched).
Start script development mode
Before you plan to modify your integration scripts, run:
nango dev # Keep the tab open
This command starts a process that continuously compiles your integration scripts and prints code syntax errors.
Write a sync script
Open the generated sync script (named [sync-name].ts) which should contain the following scaffolding :
import type { NangoSync, Contact } from '../../models';
export default async function fetchData(nango: NangoSync): Promise<void> {
// Integration code goes here.
}
Fill in the fetchData method with your integration code (in the example here, we fetch tasks from Salesforce):
import type { NangoSync, Contact } from '../../models';
export default async function fetchData(nango: NangoSync): Promise<void> {
const query = buildQuery(nango.lastSyncDate);
await fetchAndSaveRecords(nango, query);
await nango.log('Sync run completed!');
}
function buildQuery(lastSyncDate?: Date): string {
let baseQuery = `SELECT Id, FirstName, LastName, Email, AccountId, LastModifiedDate FROM Contact`;
if (lastSyncDate) { // Only fetch the new data.
baseQuery += ` WHERE LastModifiedDate > ${lastSyncDate.toISOString()}`;
}
return baseQuery;
}
async function fetchAndSaveRecords(nango: NangoSync, query: string) {
let endpoint = '/services/data/v53.0/query';
while (true) {
const response = await nango.get({
endpoint: endpoint,
params: endpoint === '/services/data/v53.0/query' ? { q: query } : {}
});
const mappedRecords = mapContacts(response.data.records);
await nango.batchSave(mappedRecords, 'SalesforceContact'); // Saves records to Nango cache.
if (response.data.done) {
break;
}
endpoint = response.data.nextRecordsUrl;
}
}
function mapContacts(records: any[]): SalesforceContact[] {
return records.map((record: any) => {
return {
id: record.Id as string,
first_name: record.FirstName,
last_name: record.LastName,
email: record.Email,
account_id: record.AccountId,
last_modified_date: record.LastModifiedDate
};
});
}
In this integration script, the following Nango utilities are used:
nango.lastSyncDateis the last date at which the sync has runawait nango.batchSave()to persist external data in Nango’s cacheawait nango.get()to perform an API request (automatically authenticated by Nango)await nango.log()to print console logs (replacesconsole.log())
Learn more about sync scripts: understanding syncs, script reference, example templates.
Write an action script
Open the generated action script (named [action-name].ts) which should contain the following scaffolding :
import type { NangoAction, FieldSchema } from '../../models';
export default async function runAction(nango: NangoAction): Promise<FieldSchema> {
// Integration code goes here.
}
Fill in the runAction method with your integration code (in the example here, we fetch available contact fields from Salesforce):
import type { NangoAction, FieldSchema } from '../../models';
export default async function runAction(nango: NangoAction): Promise<FieldSchema> {
try {
const response = await nango.get({
endpoint: '/services/data/v51.0/sobjects/Contact/describe'
});
await nango.log('Salesforce fields fetched!');
const { data } = response;
const { fields, childRelationships } = data;
return {
fields: mapFields(fields)
};
} catch (error: any) {
throw new nango.ActionError({
message: 'Failed to fetch fields in the runAction call',
details: {
message: error?.message,
method: error?.config?.method,
url: error?.config?.url,
code: error?.code
}
});
}
}
function mapFields(fields: any) {
return fields.map((field) => {
const { name, label, type, relationshipName } = field;
return {
name,
label,
type,
relationshipName: relationshipName as string
};
});
}
In this integration script, the following Nango utilities are used:
await nango.get()to perform an API request (automatically authenticated by Nango)nango.ActionError()to report errors in the execution of the integration scriptawait nango.log()to print console logs (replacesconsole.log())returnwill synchronously return results from the action trigger request
Learn more about action scripts: understanding actions, script reference, example templates.
Test your integration scripts locally
Easily test your integration scripts locally as you develop them with the dryrun function of the CLI (reference):
nango dryrun salesforce-contacts '<CONNECTION-ID>' # Sync
nango dryrun salesforce-contact-fields '<CONNECTION-ID>' # Action
nango dryrun --help # Display help for command
Because this is a dry run, syncs won’t persist data in Nango (and actions never persist data); instead, the retrieved data will be printed to the console.
By default, dryrun retrieves connections from your Dev environment.
Deploy your integration scripts
Nango provides multiple cloud environments so you can test your integration scripts more thoroughly before releasing them to customers.
To deploy all integration scripts at once, run (reference):
nango deploy dev # Deploy to your Development environment
# or
nango deploy prod # Deploy to your Production environment
In the Nango UI, navigate to the Scripts tab of the relevant integration(s) to verify the deployment succeeded.
Learn more about scripts.
Questions, problems, feedback? Please reach out in the Slack community.
Was this page helpful?