---
id: source-data-discover-customizer
title: Source Data Discover
pagination_label: Source Data Discover
sidebar_label: Source Data Discover
keywords: ['connectivity', 'connectors', 'Source Data Discover']
description: Intercept the source data discover command.
slug: /connectivity/saas-connectivity/customizers/commands/source-data-discover
tags: ['Connectivity', 'Connector Command']
---

## Overview

Use these commands to intercept the [source-data-discover](../../commands/source-data-discover) command.

| Input/Output |          Data Type          |
| :----------- | :-------------------------: |
| Input        | StdSourceDataDiscoverInput  |
| Output       | StdSourceDataDiscoverOutput |

### Example StdSourceDataDiscoverInput

```javascript
{
    "queryInput": {
        "query": "fetchAll",
        "limit": 10
    }
}
```

### Example StdSourceDataDiscoverOutput

```javascript
[
  {
    key: 'id',
    label: 'Id',
    subLabel: 'Airtable Base Id',
  },
  {
    key: 'name',
    label: 'Name',
    subLabel: 'Airtable Source Table Name',
  },
];
```

## Implementation

### Before source-data-discover command

Use this logic to implement the command:

```javascript
    .beforeStdSourceDataDiscover(async (context: Context, input: StdSourceDataDiscoverInput) => {
        logger.info(`Running before source data discover. Query: ${input.queryInput?.query}`)
        return input
    })
```

The `input` object can be mutated and returned, but the same data type must still be returned.

### After source-data-discover command

Use this logic to implement the command:

```javascript
    .afterStdSourceDataDiscover(async (context: Context, output: StdSourceDataDiscoverOutput) => {
        logger.info(`Running after source data discover first record key: ${output[0].key}`)
        return output
    })
```

The `output` object can be mutated and returned, but the same data type must still be returned.