#Commands

Commands let you define reusable commands for a tracker and execute them on demand. Two command types are supported:

• Hardware — sends a protocol-level command string directly to the device (e.g. to reboot firmware or toggle a relay).
• HTTP — sends an HTTP POST request with a JSON body to any URL, optionally embedding live device attributes in the payload.

Commands are stored per tracker and can be executed at any time from the Commands block in the platform UI.

#Object structure

Each command has a common set of fields. The config object differs by type.

{
  "id": 19,
  "name": "Reboot",
  "type": "hardware",
  "config": {
    "command": "cpureset",
    "reliable": true
  }
}

{
  "id": 20,
  "name": "Notify Slack",
  "type": "http",
  "config": {
    "url": "https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXX",
    "headers": [
      {
        "key": "Authorization",
        "value": "Bearer <TOKEN>"
      },
      {
        "key": "Content-Type",
        "value": "application/json"
      }
    ],
    "body": "{\"text\": \"Device {{device_id}}: speed {{speed}} km/h at {{latitude}}, {{longitude}}\"}"
  }
}

#Dynamic command values

A hardware command's command string, or an HTTP command's body, can include a single <> placeholder instead of a fixed value. At execution time, the caller supplies the substitution value in the param field of execute, and Mertrack replaces <> with that value before sending.

• A command's config can contain at most one <> placeholder. create and update reject a command with more than one.
• execute requires param when the command's config contains <>, and rejects param when it doesn't. Either mismatch returns error 7.
• param accepts up to 500 characters.

#API actions

API base path: /tracker/command.

#create Not available

Creates a new command for a tracker.

Required sub-user rights: tracker_update.

#Parameters

#Examples

curl -X POST 'https://api.mergroup.be/tracker/command/create' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "tracker_id": 70074765,
        "command": {
            "name": "engine_stop",
            "type": "hardware",
            "config": {
                "command": "RELAY,1#",
                "reliable": true
            }
        }
    }'

curl -X POST 'https://api.mergroup.be/tracker/command/create' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "tracker_id": 70074765,
        "command": {
            "name": "webhook_action",
            "type": "http",
            "config": {
                "url": "https://example.com/webhook",
                "headers": [
                    {
                        "key": "Authorization",
                        "value": "Bearer <TOKEN>"
                    },
                    {
                        "key": "Content-Type",
                        "value": "application/json"
                    }
                ],
                "body": "{\"tracker_id\": {{device_id}}, \"action\": \"execute_output_control\"}"
            }
        }
    }'

#Response

Returns the server-assigned id of the created command.

{
  "success": true,
  "id": 19
}

• success - boolean. Always true for successful responses.
• id - int. ID of the newly created command.

#Errors

• 7 - Invalid parameters – if required fields are missing or malformed.
• 201 - Not found in the database – if no tracker with the given tracker_id belongs to the current user.

General error codes

#update Not available

Updates an existing command. The full object including id must be provided.

Required sub-user rights: tracker_update.

#Parameters

#Examples

curl -X POST 'https://api.mergroup.be/tracker/command/update' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "tracker_id": 70074765,
        "command": {
            "id": 2,
            "name": "engine_stop_updated",
            "type": "hardware",
            "config": {
                "command": "RELAY,0#",
                "reliable": true
            }
        }
    }'

#Response

{
  "success": true
}

• success - boolean. Always true for successful responses.

#Errors

• 7 - Invalid parameters – if required fields are missing or malformed.
• 201 - Not found in the database – if the command or tracker does not exist.

General error codes

#execute Not available

Executes a command immediately. For hardware commands, the command string is sent to the device. For HTTP commands, an HTTP POST request is dispatched to the configured URL with the current device attribute values substituted into the body.

If the command's config contains a dynamic value placeholder (<>), pass the substitution value in param.

Required sub-user rights: tracker_update.

#Parameters

#Examples

curl -X POST 'https://api.mergroup.be/tracker/command/execute' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "tracker_id": 70074765,
        "command_id": 3
    }'

curl -X POST 'https://api.mergroup.be/tracker/command/execute' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "tracker_id": 70074765,
        "command_id": 3,
        "param": "1"
    }'

#Response

{
  "success": true
}

• success - boolean. Always true for successful responses.

#Errors

• 7 - Invalid parameters – if required fields are missing or malformed, if the command's config contains <> and param is missing, or if param is provided for a command without a placeholder.
• 201 - Not found in the database – if the command or tracker does not exist.

General error codes

#delete Not available

Deletes a command.

Required sub-user rights: tracker_update.

#Parameters

#Examples

curl -X POST 'https://api.mergroup.be/tracker/command/delete' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "tracker_id": 70074765,
        "command_id": 5
    }'

#Response

{
  "success": true
}

• success - boolean. Always true for successful responses.

#Errors

• 7 - Invalid parameters – if required fields are missing or malformed.
• 201 - Not found in the database – if the command or tracker does not exist.

General error codes

#Batch operations

API path: /tracker/batch_get_commands.

#batch_get_commands Not available

Returns all commands for the specified trackers, grouped by tracker ID. If trackers is omitted or empty, returns commands for all trackers accessible to the current user.

Required sub-user rights: tracker_update.

#Parameters

#Examples

curl -X POST 'https://api.mergroup.be/tracker/batch_get_commands' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key",
        "trackers": [70074765]
    }'

curl -X POST 'https://api.mergroup.be/tracker/batch_get_commands' \
    -H 'Content-Type: application/json' \
    -d '{
        "hash": "your_api_key"
    }'

#Response

Returns a result object whose keys are tracker IDs (as strings) and values are arrays of command objects for that tracker. Trackers with no configured commands return an empty array.

{
  "result": {
    "3234961": [
      {
        "id": 19,
        "name": "Reboot",
        "type": "hardware",
        "config": {
          "command": "cpureset",
          "reliable": true
        }
      },
      {
        "id": 20,
        "name": "Notify Slack",
        "type": "http",
        "config": {
          "url": "https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXXXXXX",
          "headers": [],
          "body": "{\n  \"text\": \"Device {{device_id}}: speed {{speed}} km/h at {{latitude}}, {{longitude}}\"\n}"
        }
      }
    ],
    "3490965": [],
    "3302273": []
  },
  "success": true
}

• success - boolean. Always true for successful responses.
• result - object. Keys are tracker IDs (string). Values are arrays of command objects. See object structure.

#Errors

• 7 - Invalid parameters – if the trackers array contains invalid values.

General error codes