# Connectors

A Connector enables [Publisher](https://docs.omics.ai/products/publisher) to interface with various external storage systems. They provide standardized access to files and tables while managing authentication, monitoring, and data access functionality.

## Required Connector Functionality

A Connector must fulfill these requirements:

### Configuration

* Provide an HTML user interface for configuring external connections
  * Store encrypted credentials for external systems (e.g., service accounts or dedicated user accounts)
  * Generate an audit trail for configuration changes

### Data Access

* Respond to requests about attached data by:
  * Listing files with current metadata (size, checksums, create/update dates)
  * Generating time-limited signed URLs for file retrieval
  * Listing tables with current metadata (column names & types, row count)
  * Dumping table data with optional column and row subsetting
  * Generating an audit trail for data access

### Monitoring

* Monitor external systems for data changes
  * Notify Publisher of changes
* Log all external system access, including purpose and success/fail status

## Connector Types

1. [AWS S3 Storage](https://docs.omics.ai/products/publisher/data-sources/connectors/connecting-to-aws-s3-storage)
2. [Google Cloud Storage](https://docs.omics.ai/products/publisher/data-sources/connectors/connecting-to-google-cloud-platform)
3. [Microsoft Azure Blob Storage](https://docs.omics.ai/products/publisher/data-sources/connectors/connecting-to-microsoft-azure-blob-storage)
4. [PostgreSQL](https://docs.omics.ai/products/publisher/data-sources/connectors/connecting-to-postgresql)
5. [HTTPS](https://docs.omics.ai/products/publisher/data-sources/connectors/connecting-to-https)

{% hint style="info" %}
While Publisher includes DNAstack-developed connectors, third-party developers can create additional connectors for other data sources. For information on developing custom connectors, refer to the Data Source Connector Developer Guide.
{% endhint %}