WebPrinter.submitPrintJob()

Syntax

printer.submitPrintJob(jobName, documentData, attributes)
// Promise<WebPrintJob>

Inputs

jobName is a USVString. documentData is a Blob containing a valid PDF; the only enumerated document format is application/pdf. attributes is a WebPrintJobTemplateAttributes dictionary; Chromium’s current binding requires that third argument even though the spec makes it optional with {}. Pass values advertised by fetchAttributes().

Outputs

Resolves when the browser has submitted the job and created a WebPrintJob. It does not resolve when physical printing finishes; observe the returned job.

Errors

Normative: unreachable printer → rejected NetworkError; unsupported requested capability or malformed PDF → rejected DataError. Chromium also rejects NotAllowedError for denied access. Before dispatch it throws TypeError for copies < 1, missing/zero resolution directions, or non-positive/out-of-range requested media dimensions; invalid Web IDL values also throw TypeError.

Context and permission

The IDL requires a secure, isolated context. The specification also defines the web-printing Permissions Policy with default allowlist self; Chromium additionally checks an isolated context and cross-origin isolation before getPrinters(). The current proposal requires express, origin-specific consent triggered by enumeration. The exact chooser scope, persistence, and whether a later operation prompts again remain user-agent UX, not a settled web contract.

Lifecycle, cancellation, and cleanup

Submission refreshes capabilities before matching attributes in the normative algorithm. Use an AbortSignal in the attributes to request cancellation after a job object exists; aborting is best effort and no success/settlement guarantee is defined. Retrying can duplicate printed output, so only retry after user confirmation.

Examples

async function submitPdf(printer, pdfResponse) {
  const documentData = await pdfResponse.blob();
  if (documentData.type && documentData.type !== "application/pdf") {
    throw new TypeError("Expected an application/pdf response");
  }
  const capabilities = await printer.fetchAttributes();
  if (!capabilities.documentFormatSupported?.includes("application/pdf")) {
    throw new Error("Printer did not report PDF support");
  }
  return printer.submitPrintJob("Monthly report", documentData, {
    copies: 1,
    sides: "one-sided",
  });
}

Browser compatibility

Security and privacy

Printer names, IDs, capabilities and state can fingerprint a device and reveal printing activity. A compromised IWA could create unwanted jobs or denial of service. Minimize enumeration and polling, do not expose attributes to untrusted content, validate documents before submitting, and offer an app-level confirmation/audit trail. The spec requires isolation and consent; it does not make printer information non-sensitive.

Canonical sources

• WICG normative specification
• Chromium WebPrinter IDL and implementation
• Chromium printing Mojo contract
• WICG explainer
• ChromeStatus record
• RFC 8011 IPP attributes