Get Shipping Label ZPL

API Overview

Generates the CN23 shipping label for a parcel and returns it as ZPL, ready to send straight to a Zebra-compatible thermal printer.

The parcel must already exist and must be identified by its WMG tracking number — obtain it from Get Tracking No if you only hold your own reference.

Request Information

• Method: POST
• Path: /api/create-label-zpl
• Authentication: Bearer Token

Request Headers

Field	Description
Content-Type	application/json
Authorization	Bearer <token>

Request Parameters

The request body is in JSON format and includes the following fields:

Parameter	Type	Required	Description
Barcode	string	Yes	The WMG tracking number of the parcel, maximum 50 characters.
LabelType	string	Yes	Label type. Currently only CN23 is available. Maximum 10 characters.
Origin	string	Yes	Originating country as a 2-letter code, e.g. SG for Singapore, TW for Taiwan.
Destination	string	Yes	Destination country as a 2-letter code, e.g. TW for Taiwan, JP for Japan.

Request Body Example

{
    "Barcode": "CY180000662SG",
    "LabelType": "CN23",
    "Origin": "SG",
    "Destination": "JP"
}

Authentication

This endpoint uses Bearer token authentication.

Obtain a token from Get Token and send it as Authorization: Bearer <Token>.

Response Information

The response is in JSON format.

Response Format

Field	Type	Description
Code	integer	0 = success; non-zero = failure
Message	string	Human-readable result
Data	object	Payload; empty array [] on failure

Success Response

• Status Code: 200

{
    "Code": 0,
    "Message": "Success",
    "Data": {
        "Zpl": "^XA^GFA,7200,7200,90,:Z64:eJzt3D1v2zAQBuC..."
    }
}

The Zpl value is truncated in this example. The real response contains the complete ZPL command stream.

Field	Type	Description
Data.Zpl	string	The CN23 label as a ZPL command stream. Send it to the printer as-is.

Error Response

• Status Code: 200 (business logic error) or 4xx/5xx (system error)

{
    "Code": 1,
    "Message": "Parcel not found",
    "Data": []
}

Code Reference

Code	Description
0	Success
1	Failure

Example

Bash

BASE_URL="https://api.postal.test.wmgdelivery.com"
TOKEN="your_access_token"

curl -X POST "$BASE_URL/api/create-label-zpl" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $TOKEN" \
  -d '{"Barcode":"CY180000662SG","LabelType":"CN23","Origin":"SG","Destination":"JP"}'

Windows PowerShell

$BASE_URL = "https://api.postal.test.wmgdelivery.com"
$TOKEN    = "your_access_token"

$body = @{
    Barcode     = "CY180000662SG"
    LabelType   = "CN23"
    Origin      = "SG"
    Destination = "JP"
} | ConvertTo-Json

$response = Invoke-RestMethod -Uri "$BASE_URL/api/create-label-zpl" -Method Post `
    -ContentType "application/json" -Body $body -Headers @{Authorization = "Bearer $TOKEN"}

# Write the raw ZPL out for the printer (no trailing newline, no BOM)
[IO.File]::WriteAllText("label.zpl", $response.Data.Zpl)

Python

import requests

BASE_URL = "https://api.postal.test.wmgdelivery.com"
TOKEN    = "your_access_token"

resp = requests.post(f"{BASE_URL}/api/create-label-zpl", json={
    "Barcode": "CY180000662SG",
    "LabelType": "CN23",
    "Origin": "SG",
    "Destination": "JP",
}, headers={"Authorization": f"Bearer {TOKEN}"}, timeout=30)
payload = resp.json()

# Write the raw ZPL out for the printer
with open("label.zpl", "w", encoding="utf-8", newline="") as fh:
    fh.write(payload["Data"]["Zpl"])

Node.js / TypeScript

import {writeFileSync} from "node:fs";

const BASE_URL = "https://api.postal.test.wmgdelivery.com";
const TOKEN = "your_access_token";

const res = await fetch(`${BASE_URL}/api/create-label-zpl`, {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Authorization": `Bearer ${TOKEN}`,
  },
  body: JSON.stringify({
    Barcode: "CY180000662SG",
    LabelType: "CN23",
    Origin: "SG",
    Destination: "JP",
  }),
});
const payload = await res.json();

// Write the raw ZPL out for the printer
writeFileSync("label.zpl", payload.Data.Zpl, "utf8");

PHP

<?php
$BASE_URL = 'https://api.postal.test.wmgdelivery.com';
$TOKEN    = 'your_access_token';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $BASE_URL . '/api/create-label-zpl');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Content-Type: application/json',
    'Authorization: Bearer ' . $TOKEN,
]);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
    'Barcode'     => 'CY180000662SG',
    'LabelType'   => 'CN23',
    'Origin'      => 'SG',
    'Destination' => 'JP',
]));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 30);
$response = curl_exec($ch);
curl_close($ch);

$payload = json_decode($response, true);

// Write the raw ZPL out for the printer
file_put_contents('label.zpl', $payload['Data']['Zpl']);
?>

Notes

• Barcode must be the WMG tracking number, not your own reference.
• Barcode is normalised to upper case before matching. Origin and Destination are matched exactly as sent, so send them in upper case.
• The ZPL is produced by rendering the PDF label and converting it to a raster image embedded in a ZPL command stream. Every condition that applies to Get Shipping Label PDF therefore applies here too.
• Because of that conversion step, this is the slowest of the three label endpoints — allow a generous client timeout.
• The label is always rendered in the default orientation; this endpoint has no Direction parameter.
• Generating a label records a label event against the parcel, so it becomes visible in the parcel's tracking history.
• Parcels shipped under a self-label service cannot be labelled through this endpoint and return The package cannot undergo this operation.
• LabelType is validated for length but does not change the generated label. Send CN23.
• All other parameters are case-sensitive.

Error Codes

code	message	Description
1	Parcel not found	No parcel in your account matches the supplied Barcode, Origin and Destination.
1	The package cannot undergo this operation	The parcel ships under a self-label service, so WMG does not generate its label.
1	Barcode require	Barcode is missing or empty.
1	max size of Barcode must be 50	Barcode is longer than 50 characters.
1	LabelType require	LabelType is missing or empty.
1	max size of LabelType must be 10	LabelType is longer than 10 characters.
1	Origin require	Origin is missing or empty.
1	max size of Origin must be 2	Origin is longer than 2 characters.
1	Destination require	Destination is missing or empty.
1	max size of Destination must be 2	Destination is longer than 2 characters.
1	Error encountered, please contact tech@wmg-group.com with screenshot of error page for resolution.	Unexpected server error.
1003	Token error	The token is missing, expired, or superseded by a newer login. Call Get Token again.