API support for receiving attribute expressions in all places a ColumnIdentifier is currently received

[kotharironak]

Based on the discussion, accept the new AttributeExpression as Query Service Request, and provide similar support for it same as ColumnIdentifer.

  AttributeExpression {
    attributeId: String!
    subpath: String
  }

Currently, we have ColumnIdentifer support in Query Service request in:

• selection
• groupby
• filter
• order by clause

Provide similar support for AttributeExpression in QuerySerivce.

E.g of Filter using ColumnIdentifer

childFilter {
      lhs {
        columnIdentifier {
          columnName: "BACKEND.startTime"
        }
      }
      operator: LT
      rhs {
        literal {
          value {
            valueType: LONG
            long: 1631178754903
          }
        }
      }

Support for AttributeExpression

childFilter {
      lhs {
        attributeExpression {
          attributeId: "BACKEND.startTime"
        }
      }
      operator: LT
      rhs {
        literal {
          value {
            valueType: LONG
            long: 1631178754903
          }
        }
      }

If you have a test, in both the above cases, it will convert to the same pinot query, and the response builder will have the same response.

Reference:

See the reference UI ticket - hypertrace/hypertrace-ui#1099 and discussion.