DataHub Provider¶

The DataHub provider connects mcp-trino to DataHub, an open-source metadata platform. It retrieves table descriptions, ownership, tags, glossary terms, domains, and column-level metadata via DataHub's GraphQL API.

Configuration¶

Environment Variable	Required	Default	Description
`DATAHUB_ENDPOINT`	Yes	-	DataHub GraphQL endpoint URL
`DATAHUB_TOKEN`	Yes	-	Authentication token
`DATAHUB_PLATFORM`	No	`trino`	Data platform name in URNs
`DATAHUB_ENVIRONMENT`	No	`PROD`	DataHub environment
`DATAHUB_TIMEOUT`	No	`30s`	Request timeout

Example¶

export DATAHUB_ENDPOINT=https://datahub.example.com/api/graphql
export DATAHUB_TOKEN=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
export DATAHUB_PLATFORM=trino
export DATAHUB_ENVIRONMENT=PROD

URN Mapping¶

DataHub identifies datasets using URNs (Uniform Resource Names). The provider maps Trino table identifiers to DataHub URNs:

Trino: catalog.schema.table
DataHub: urn:li:dataset:(urn:li:dataPlatform:{platform},{catalog}.{schema}.{table},{environment})

For example, with default settings:

Trino Table	DataHub URN
`hive.analytics.customers`	`urn:li:dataset:(urn:li:dataPlatform:trino,hive.analytics.customers,PROD)`
`iceberg.sales.orders`	`urn:li:dataset:(urn:li:dataPlatform:trino,iceberg.sales.orders,PROD)`

Custom Platform Names¶

If your DataHub instance uses a different platform name for Trino datasets:

export DATAHUB_PLATFORM=trino-prod

Multi-Environment¶

For staging or development environments:

export DATAHUB_ENVIRONMENT=DEV

Supported Metadata¶

The provider retrieves the following metadata from DataHub:

Table-Level¶

Metadata	DataHub Source
Description	Dataset properties
Ownership	Ownership aspect with roles
Tags	Global tags with descriptions
Glossary Terms	Glossary term associations
Domain	Domain assignment
Deprecation	Deprecation aspect

Column-Level¶

Metadata	DataHub Source
Description	Schema field description
Tags	Field-level tags
Glossary Terms	Field-level term associations
Sensitivity	Tags containing "pii" or "sensitive"

Sensitivity Detection¶

The provider automatically marks columns as sensitive when they have tags containing:

pii
sensitive

For example, a column with tag pii-email or sensitive-data will be marked as sensitive in the output.

Library Usage¶

import (
    "github.com/txn2/mcp-trino/pkg/semantic/providers/datahub"
    "github.com/txn2/mcp-trino/pkg/tools"
)

// Create provider from environment
provider, err := datahub.New(datahub.FromEnv())
if err != nil {
    log.Fatal(err)
}
defer provider.Close()

// Or configure programmatically
provider, err := datahub.New(datahub.Config{
    Endpoint:    "https://datahub.example.com/api/graphql",
    Token:       "your-token",
    Platform:    "trino",
    Environment: "PROD",
    Timeout:     30 * time.Second,
})

// Add to toolkit
toolkit := tools.NewToolkit(trinoClient, cfg,
    tools.WithSemanticProvider(provider),
    tools.WithSemanticCache(semantic.DefaultCacheConfig()),
)

Error Handling¶

The provider follows these conventions:

Returns nil (not an error) when metadata is not found
Returns errors only for connection or authentication failures
Logs warnings for malformed URNs or unexpected responses

This ensures that missing metadata doesn't break tool execution.

Troubleshooting¶

Authentication Errors¶

datahub: token is required

Ensure DATAHUB_TOKEN is set with a valid access token from DataHub.

Connection Timeouts¶

context deadline exceeded

Increase the timeout or check network connectivity:

export DATAHUB_TIMEOUT=60s

Dataset Not Found¶

If metadata isn't appearing, verify the URN mapping:

Check the platform name matches DataHub's configuration
Verify the environment (PROD, DEV, etc.)
Confirm the dataset exists in DataHub with the expected URN

Use DataHub's search or browse interface to find the exact URN for a dataset.