Microsoft Power Automate

Prerequisites

A PolyDoc account and API key - sign up for free, no credit card required. The free plan includes 150 PDF conversions per month.
A Microsoft Power Automate account with Power Automate Premium (or the free 90-day Premium trial). The PolyDoc call uses the HTTP action and the Request / Response connectors, which are premium - see the note below.

Generate a PDF from an HTTP request

Expose a Power Automate cloud flow as an HTTP endpoint, forward the request to PolyDoc, and return the rendered PDF in the response - a serverless "HTML/template → PDF" microservice you can call from any app, Power App, or another flow.
When an HTTP request is received (trigger) → HTTP (call PolyDoc) → Response (return the PDF)

Power Automate Premium is required. The generic HTTP action and the Request / Response connectors used here are premium connectors. On a plan without premium, the flow saves but shows "This flow's owner needs a Power Automate Premium license" and won't run. Start the free 90-day Premium trial (offered right in the flow checker) or assign a Premium license, then re-save the flow.

PolyDoc returns the PDF as raw binary in the HTTP response body. Power Automate carries that straight through - bind the Response action's Body to the HTTP action's Body output and the caller receives a real application/pdf download. No base64 round-trip needed.

Create an instant flow with an HTTP request trigger

In Power Automate choose Create → Instant cloud flow, then pick the When an HTTP request is received trigger (from the Request connector). Leave Who can trigger the flow? on Any user in my tenant. The endpoint HTTP URL is generated when you first save the flow - copy it then; it carries a signed sig token, so treat it as a secret.

You can leave Request Body JSON Schema empty for this pattern - the flow forwards a fixed payload to PolyDoc. Fill it in only if you want to map fields from the incoming request into the template.

Add the HTTP action that calls PolyDoc

Click + below the trigger, search HTTP, and add the HTTP action. Configure it to call PolyDoc:

URI: https://api.polydoc.tech/pdf/convert
Method: POST
Headers: Authorization = Bearer YOUR_API_KEY, Content-Type = application/json, X-Sandbox = true
Body: the JSON below

{
  "source": "[template:YOUR_TEMPLATE_ID]",
  "templateData": {
    "invoice_number": "INV-2026-001",
    "invoice_date": "2026-01-15",
    "invoice_due_date": "2026-02-14",
    "invoice_subtotal": 1200,
    "invoice_tax_rate": 0.1,
    "invoice_tax_amount": 120,
    "invoice_total": 1320,
    "customer_name": "John Doe",
    "customer_email": "john.doe@example.com",
    "customer_street": "456 Customer Avenue",
    "customer_city": "Beautiful City",
    "customer_country": "UK",
    "items": [
      {"quantity": 1, "name": "Web Design Services", "description": "Custom website design and development for company homepage", "price": 800},
      {"quantity": 1, "name": "Logo Design", "description": "Professional logo design with 3 revision rounds", "price": 300},
      {"quantity": 1, "name": "SEO Optimization", "description": "Search engine optimization for 10 target keywords", "price": 100, "original_price": 150}
    ]
  }
}

Replace YOUR_API_KEY with the key from the Dashboard and YOUR_TEMPLATE_ID with your template short ID from the Dashboard Templates page (e.g. a1b-c2d).

To drive the template from the incoming request instead of a fixed payload, replace each value with a reference to the trigger body, e.g. @{triggerBody()?['invoice_number']}. Wrap numeric fields in int(...) / float(...) (for example @{float(triggerBody()?['invoice_total'])}) - request JSON often arrives with numbers as strings, and an unquoted-looking "1320" renders as text in the PDF instead of a number.

Keep the X-Sandbox: true header while testing - the response is a watermarked PDF that doesn't count against your quota. Remove it once you go live.

This example uses a template as source. You can also send raw HTML or a URL - see the Templates section.

Return the PDF in the response

Add a Response action (from the Request connector) after the HTTP action so the caller gets the PDF back:

Status Code: 200
Headers: Content-Type = application/pdf
Body: the Body dynamic-content token from the HTTP step (expression body('HTTP'))

Don't wrap the body token in quotes or string interpolation - body('HTTP') on its own passes the raw PDF bytes through. Wrapping it (@{body('HTTP')}) stringifies the binary and corrupts the download.

Save and test the endpoint

Save the flow. The flow checker should show "Your flow is ready to go" with no errors (if it instead flags a license warning, enable Premium - see the note at the top). Copy the trigger's HTTP URL and POST to it to get a PDF back:

curl -X POST '<your-flow-http-url>' \
  -H 'Content-Type: application/json' \
  --data-raw '{}' \
  --output invoice.pdf

Open invoice.pdf - it's the rendered template with the SANDBOX watermark while the X-Sandbox header is set. Every run is also listed under the flow's 28-day run history, where you can inspect the HTTP action's inputs and outputs.

Prerequisites​

Generate a PDF from an HTTP request​

Create an instant flow with an HTTP request trigger​

Add the HTTP action that calls PolyDoc​

Return the PDF in the response​