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How to Attach Evidence to Multiple Events Using Postman (Step-by-Step) This guide explains how to upload a CSV evidence file to multiple Mangrove events in bulk using Postman. Prerequisites Before starting, make sure you have: • A Mangrove API token  • A CSV list of event IDs you want to attach evidence to  • Your evidence file ready (CSV in this example)  • Postman application Step 1 - Create a Collection and Request Open PostmanCreate a new Collection (e.g., Mangrove Evidence Upload)Inside the collection, click Add Request Step 2 - Configure the Endpoint URL Copy the “Create evidence on event” endpoint from Mangrove API docsPaste it into the request URL fieldReplace project_id with your project IDReplace the event ID in the URL with a variable: Step 3 - Set Authorization Go to the Authorization tab Set Type to Bearer TokenPaste your Mangrove API token into the token field Step 4 - Add Headers Go to the Headers tab and add: Key: Content-Type Value: application/json Step 5 - Add the Request Body Go to the Body tab Select raw Paste the following: 
{
  "evidences": [
    {
      "type": "file",
      "data": {
        "file": {
          "name": "{{file_name}}",
          "type": "text/csv",
          "base64": "{{file_base64}}"
        }
      }
    }
  ]
}
Your request is now fully configured. Step 6 - Convert the Evidence File to Base64 (macOS) Open Terminal and run: base64 -i path/to/your/file.csv | pbcopyThis converts your file into base64 and copies it to your clipboard. Step 7 - Prepare the Runner Data File (events.csv) Create a file called events.csv with these columns: event_id,file_name,file_base64Example: event_id,file_name,file_base64 evt_001,evidence.csv,AAAABBBB… evt_002,evidence.csv,AAAABBBB… evt_003,evidence.csv,AAAABBBB…Column definitions: • event_id → event you want to attach evidence to  • file_name → file name displayed in Mangrove  • file_base64 → base64 string of your evidence file If you’re attaching the same file to multiple events, reuse the same base64 value across rows. Save the file. Step 8 - Run the Collection In Postman, open your CollectionClick RunUpload events.csv as the data fileClick RunPostman will send one request per row in your CSV file. If everything is configured correctly, the number of successful responses should match the number of rows in your file.