Label LIVE

Integrate a label printer via Label LIVE's HTTP REST API.

Example Printer Configuration

You'll need to do the following for this configuration to work:

Replace the choices in options.host to the address of your computer that is running Label LIVE.
Download the Sample Label Designs, open them with Label LIVE and pin them to the home screen.
Replace your-printer-id in the config to your actual printer name in Label LIVE. (How to find your printer ID?)

{
  options: {
    // You should keep Label LIVE running on the machine to respond to API requests
    host: {
      type: 'string',
      choices: [
        'http://192.168.88.123:11180',
        'https://example.com',
        // ...
      ],
      saveLastValue: true,
    },
    // Get these sample designs in the Sample Label Designs section below
    design: {
      enum: [
        '70×20 Two Lines with QR Code',
        '70×20 QR Code with Asset Reference Number',
        // ...
      ],
      saveLastValue: true,
    },
    use_preview_printer: {
      type: 'boolean',
      default: false,
      saveLastValue: false,
    },
  },
  getLabel: ({ item, options, utils }) => {
    switch (options.design) {
      case '70×20 Two Lines with QR Code': {
        const itemName = item.name.trim();
        const { nextLine: line_1, remaining: line_2 } = utils.getNextLine(
          itemName,
          18,
        );
        return {
          LINE_1: line_1.trim() || ' ',
          LINE_2: line_2.trim() || ' ',
          SIDE: item.collection.name,
          QR_CODE_DATA: item.individual_asset_reference
            ? `z-inv://iar/${item.individual_asset_reference}`
            : `z-inv://item/${item.__id}`,
        };
      }
      case '70×20 QR Code with Asset Reference Number': {
        return {
          ASSET_REFERENCE_NUMBER: item.individual_asset_reference || ' ',
          QR_CODE_DATA: item.individual_asset_reference
            ? `z-inv://iar/${item.individual_asset_reference}`
            : `z-inv://item/${item.__id}`,
        };
      }
      default: {
        throw new Error(`Design not handled in getLabel: "${options.design}"`);
      }
    }
  },
  getPreview: ({ options, label, utils }) => {
    const size = (() => {
      switch (options.design) {
        case '70×20 Two Lines with QR Code': {
          // You can open a preview image in the browser to get its size.
          return {
            width: 827,
            height: 237,
          };
        }
        case '70×20 QR Code with Asset Reference Number': {
          // You can open a preview image in the browser to get its size.
          return {
            width: 827,
            height: 237,
          };
        }
        default: {
          throw new Error(
            `Design not handled in getPreview: "${options.design}"`,
          );
        }
      }
    })();

    return {
      uri: [
        options.host,
        '/api/v1/print?design=',
        encodeURIComponent(options.design),
        '&variables=',
        encodeURIComponent(JSON.stringify(label)),
      ].join(''),
      ...size,
    };
  },
  print: ({ options, labels, utils, signal }) => {
    const { host, design } = options;

    // With multiple printers connected to the same computer,
    // you can support printing designs on multiple sizes of labels.
    const designPrinterMap = {
      '70×20 Two Lines with QR Code': 'your-printer-id',
      '70×20 QR Code with Asset Reference Number': 'your-printer-id',
    };

    const printer = options.use_preview_printer
      ? 'Preview'
      : designPrinterMap[options.design];

    return Promise.all(
      labels.map(label => {
        return fetch(
          [
            host,
            '/api/v1/print?design=',
            encodeURIComponent(options.design),
            '&variables=',
            encodeURIComponent(JSON.stringify(label)),
            '&printer=',
            printer,
            '&copies=1',
          ].join(''),
          {
            signal /* this is used to let the user abort the fetch */,
            method: 'POST',
          },
        )
          .then(response => response.json())
          .then(json => {
            if (!json.success) {
              // Error will be shown on the UI
              throw new Error(json.error);
            }
          });
      }),
    );
  },
}