mongodb-aggregate

About

The mongodb-aggregate tool is the most powerful query tool for MongoDB, allowing you to process data through a multi-stage pipeline. Each stage transforms the documents as they pass through, enabling complex operations like grouping, filtering, reshaping documents, and performing calculations.

The core of this tool is the pipelinePayload, which must be a string containing a JSON array of pipeline stage documents. The tool returns a JSON array of documents produced by the final stage of the pipeline.

A readOnly flag can be set to true as a safety measure to ensure the pipeline does not contain any write stages (like $out or $merge).

This tool is compatible with the following source kind:

• mongodb

Example

Here is an example that calculates the average price and total count of products for each category, but only for products with an “active” status.

tools:
  get_category_stats:
    kind: mongodb-aggregate
    source: my-mongo-source
    description: Calculates average price and count of products, grouped by category.
    database: ecommerce
    collection: products
    readOnly: true
    pipelinePayload: |
      [
        {
          "$match": {
            "status": {{json .status_filter}}
          }
        },
        {
          "$group": {
            "_id": "$category",
            "average_price": { "$avg": "$price" },
            "item_count": { "$sum": 1 }
          }
        },
        {
          "$sort": {
            "average_price": -1
          }
        }
      ]
    pipelineParams:
      - name: status_filter
        type: string
        description: The product status to filter by (e.g., "active").

Reference