Transforming Values in a DataHub Connector (Example: Formatting Asset ID)

Overview

sometime, source data must be transformed to meet system requirements. This example shows how to convert numeric IDs into a formatted Asset ID. It shows three types of transformations. Adding text to beginning, putting in a thousand's comma, left filling with zeros

Scenario

Input:

1
200
22456

Required Output:

Client-000,001
Client-000,200
Client-022,456

Implementation

Use a mutator to:

1. Parse the number
2. Pad with zeros
3. Add prefix
4. Insert thousands separator

Steps to write the mutator:

Example Mutator

 
return function mutate(sourceData, columnNames, rowObject, connectionData, createError) {
 
     const [raw] = sourceData;
 
    if (raw == null || raw === "") {
        createError("AssetID is missing");
        return null;
    }
 
   const id = parseInt(raw);
 
    if (isNaN(id)) {
        createError("Invalid AssetID: " + raw);
        return null;
    }
 
    let str = id + "";
 
    while (str.length < 6) {
        str = "0" + str;
    }
 
    // Add comma separator
    var formatted = str.slice(0, 3) + "," + str.slice(3);
 
    return ["Client-" + formatted];
}

Output Examples

Input

1 200 22456

Output

Client-000,001

Client-000,200

Client-022,456

Notes

• Always validate input before transformation
• Avoid modifying source files
• This example perform all formatting within DataHub, but you might want to make the changes before it gets to DataHub in other cases.