{ "name": "Generate PDF invoices from webhook data with PDFMint", "nodes": [ { "id": "Sticky Note", "name": "Sticky Note", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ -800, -380 ], "parameters": { "color": 1, "width": 620, "height": 1080, "content": "## Generate PDF invoices from webhook data with PDFMint\n\n**Who's it for**\nAnyone whose shop, billing system or internal tool can POST JSON and needs a finished PDF invoice back in the same request — without running a headless browser, and without a template editor to log into.\n\n**How it works**\n1. **Receive invoice data** accepts a POST with the customer, the line items and the currency.\n2. **Set your company details** is the one node you edit: company name, address, VAT rate, payment terms and footer note.\n3. **Check the request is complete** rejects a request that has no customer or no line items *before* a PDF is rendered, so a broken payload gets a readable 422 instead of an invoice that says \"undefined\".\n4. **Calculate line totals and VAT** does the arithmetic in one place: per-line amounts, subtotal, VAT at your rate, grand total, and the due date derived from your payment terms. The HTML stays a layout, not a calculator.\n5. **Render the invoice as PDF** builds the document with PDFMint. The layout is plain HTML and CSS inside the node, so you change the design by editing markup.\n6. **Did the render succeed?** checks the render result. On success **Return the PDF** answers the original request with the file; if PDFMint could not be reached or refused the job, **Explain what went wrong** and **Return the error as JSON** answer with the right error status — 422 for a broken payload, 500 when the render itself fails — plus the reason. The caller always gets an answer.\n\n**How to set up**\n- Add a PDFMint credential (free plan: 10 documents a month, no card).\n- Open **Set your company details** and put in your own company name, address, VAT rate and payment terms.\n- Activate the workflow and POST to the production webhook URL.\n\n**Requirements**\n- A PDFMint API key from pdf.mintapis.com.\n- ⚠️ This template uses a community node, so it runs on **self-hosted n8n only**.\n\n**How to customize**\nEdit the HTML in **Render the invoice as PDF** for your own branding — line items are looped in one expression, so any number of rows works. Set `vat_percent` to `0` if you do not charge VAT. Swap **Return the PDF** for a Gmail, Drive or S3 node to deliver the invoice instead of returning it." } }, { "id": "Sticky Note1", "name": "Sticky Note1", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ -100, -480 ], "parameters": { "color": 7, "width": 300, "height": 200, "content": "### 1. The request comes in\nPOST the invoice as JSON. Required: `customer_name` and a `line_items` array of `description` / `quantity` / `unit_price`. Optional: `currency`, `customer_email`, `invoice_number`." } }, { "id": "Sticky Note2", "name": "Sticky Note2", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ 240, -480 ], "parameters": { "color": 7, "width": 300, "height": 200, "content": "### 2. Edit this node, not the others\nYour company name, address, VAT rate, payment terms and footer note. Every other node reads its settings from here." } }, { "id": "Sticky Note3", "name": "Sticky Note3", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ 580, -480 ], "parameters": { "color": 7, "width": 300, "height": 200, "content": "### 3. Refuse a broken payload early\nNo customer or no line items means no PDF is worth rendering. The request is answered with a readable reason instead of an invoice full of `undefined`." } }, { "id": "Sticky Note4", "name": "Sticky Note4", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ 920, -480 ], "parameters": { "color": 7, "width": 300, "height": 200, "content": "### 4. All the arithmetic, in one place\nPer-line amounts, subtotal, VAT at your rate, grand total, and the due date derived from your payment terms — computed here so the HTML stays a layout." } }, { "id": "Sticky Note5", "name": "Sticky Note5", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ 1260, -480 ], "parameters": { "color": 7, "width": 300, "height": 200, "content": "### 5. HTML in, PDF out\nThe invoice layout is ordinary HTML and CSS in this node. No template editor, no template ids — edit the markup and the next render changes." } }, { "id": "Sticky Note6", "name": "Sticky Note6", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ 1600, -480 ], "parameters": { "color": 7, "width": 300, "height": 200, "content": "### 6. Did a PDF actually come back?\nThe render node is set to *continue* on failure, so an unreachable API or a refused job arrives here as data instead of stopping the workflow. This node decides which of the two answers the caller gets." } }, { "id": "Sticky Note7", "name": "Sticky Note7", "type": "n8n-nodes-base.stickyNote", "typeVersion": 1, "position": [ 1940, -480 ], "parameters": { "color": 7, "width": 320, "height": 220, "content": "### 7. The caller always gets an answer\nOn success the POST is answered with the PDF itself; on failure with an error status (422 for a bad payload, 500 when the render itself fails) and the reason, so the request never hangs. Replace **Return the PDF** with Gmail, Drive or S3 if you would rather deliver the file somewhere." } }, { "parameters": { "httpMethod": "POST", "path": "invoice", "responseMode": "responseNode", "options": {} }, "id": "n1", "name": "Receive invoice data", "type": "n8n-nodes-base.webhook", "typeVersion": 2, "position": [ -40, 0 ] }, { "parameters": { "assignments": { "assignments": [ { "id": "f1", "name": "seller_name", "value": "Your Company Ltd", "type": "string" }, { "id": "f2", "name": "seller_address", "value": "1 Example Street, 12345 Your City", "type": "string" }, { "id": "f3", "name": "footer_note", "value": "Thank you for your business.", "type": "string" }, { "id": "f4", "name": "default_currency", "value": "EUR", "type": "string" }, { "id": "f5", "name": "vat_percent", "value": 19, "type": "number" }, { "id": "f6", "name": "payment_terms_days", "value": 14, "type": "number" } ] }, "includeOtherFields": true, "options": {} }, "id": "n2", "name": "Set your company details", "type": "n8n-nodes-base.set", "typeVersion": 3.4, "position": [ 300, 0 ] }, { "parameters": { "conditions": { "options": { "caseSensitive": true, "leftValue": "", "typeValidation": "loose", "version": 2 }, "conditions": [ { "id": "c1", "leftValue": "={{ $json.body.customer_name }}", "rightValue": "", "operator": { "type": "string", "operation": "notEmpty", "singleValue": true } }, { "id": "c2", "leftValue": "={{ $json.body.line_items }}", "rightValue": "", "operator": { "type": "array", "operation": "notEmpty", "singleValue": true } } ], "combinator": "and" }, "looseTypeValidation": true, "options": {} }, "id": "n3", "name": "Check the request is complete", "type": "n8n-nodes-base.if", "typeVersion": 2.2, "position": [ 640, 0 ] }, { "parameters": { "jsCode": "// Everything the invoice needs is worked out here, once, so the HTML stays a layout\n// and not a calculator: per-line amounts, subtotal, VAT, grand total, and the dates\n// that follow from your payment terms.\nconst item = $input.first().json;\nconst body = item.body || {};\n\nconst currency = String(body.currency || item.default_currency || 'EUR').toUpperCase();\nconst vatPercent = Number(item.vat_percent) || 0;\nconst termsDays = Number(item.payment_terms_days) || 14;\nconst money = (n) => currency + ' ' + n.toFixed(2);\n\nconst rows = (body.line_items || []).map((li) => {\n const quantity = Number(li.quantity) || 0;\n const unitPrice = Number(li.unit_price) || 0;\n const amount = Math.round(quantity * unitPrice * 100) / 100;\n return {\n description: String(li.description || 'Item'),\n quantity,\n unit_display: money(unitPrice),\n amount,\n amount_display: money(amount),\n };\n});\n\nconst subtotal = Math.round(rows.reduce((sum, r) => sum + r.amount, 0) * 100) / 100;\nconst vat = Math.round(subtotal * vatPercent) / 100;\nconst total = Math.round((subtotal + vat) * 100) / 100;\n\nconst pad = (n) => String(n).padStart(2, '0');\nconst issued = new Date();\nconst due = new Date(issued.getTime() + termsDays * 86400000);\nconst stamp = `${issued.getFullYear()}${pad(issued.getMonth() + 1)}${pad(issued.getDate())}`;\nconst show = (d) => d.toLocaleDateString('en-GB', { day: '2-digit', month: 'short', year: 'numeric' });\n\nreturn [{\n json: {\n seller_name: item.seller_name,\n seller_address: item.seller_address,\n footer_note: item.footer_note,\n customer_name: body.customer_name,\n customer_email: body.customer_email || '',\n invoice_number: body.invoice_number || `INV-${stamp}-1`,\n issue_date: show(issued),\n due_date: show(due),\n currency,\n vat_percent: vatPercent,\n rows,\n subtotal,\n subtotal_display: money(subtotal),\n vat,\n vat_display: money(vat),\n total,\n total_display: money(total),\n },\n}];" }, "id": "n4", "name": "Calculate line totals and VAT", "type": "n8n-nodes-base.code", "typeVersion": 2, "position": [ 980, -80 ] }, { "parameters": { "resource": "document", "operation": "pdf", "source": "html", "html": "=\n

{{ $json.seller_name }}

\n
{{ $json.seller_address }}
\n
\n
Billed to
{{ $json.customer_name }}
{{ $json.customer_email }}
\n
Invoice {{ $json.invoice_number }}
Issued {{ $json.issue_date }}
Due {{ $json.due_date }}
\n
\n\n{{ $json.rows.map(r => '').join('') }}\n
DescriptionQtyUnitAmount
' + r.description + '' + r.quantity + '' + r.unit_display + '' + r.amount_display + '
\n
\n
Subtotal{{ $json.subtotal_display }}
\n
VAT {{ $json.vat_percent }}%{{ $json.vat_display }}
\n
Total{{ $json.total_display }}
\n
\n

{{ $json.footer_note }}

\n", "options": {}, "fileName": "=invoice-{{ $json.invoice_number }}.pdf" }, "id": "n5", "name": "Render the invoice as PDF", "type": "n8n-nodes-pdfmint.pdfMint", "typeVersion": 1, "position": [ 1320, -80 ], "onError": "continueRegularOutput", "credentials": { "pdfMintApi": { "name": "PDFMint account" } } }, { "parameters": { "conditions": { "options": { "caseSensitive": true, "leftValue": "", "typeValidation": "loose", "version": 2 }, "conditions": [ { "id": "c3", "leftValue": "={{ $json.error }}", "rightValue": "", "operator": { "type": "object", "operation": "notExists", "singleValue": true } } ], "combinator": "and" }, "looseTypeValidation": true, "options": {} }, "id": "n6", "name": "Did the render succeed?", "type": "n8n-nodes-base.if", "typeVersion": 2.2, "position": [ 1660, -80 ] }, { "parameters": { "respondWith": "binary", "options": {} }, "id": "n7", "name": "Return the PDF", "type": "n8n-nodes-base.respondToWebhook", "typeVersion": 1.1, "position": [ 2000, -180 ] }, { "parameters": { "assignments": { "assignments": [ { "id": "e1", "name": "error", "value": "invoice_not_generated", "type": "string" }, { "id": "e2", "name": "message", "value": "={{ $json.error ? 'The invoice could not be rendered: ' + ($json.error.message || $json.error) : 'Send a customer_name and a non-empty line_items array.' }}", "type": "string" }, { "id": "e3", "name": "status_code", "value": "={{ $json.error ? 500 : 422 }}", "type": "number" } ] }, "includeOtherFields": false, "options": {} }, "id": "n8", "name": "Explain what went wrong", "type": "n8n-nodes-base.set", "typeVersion": 3.4, "position": [ 1660, 180 ] }, { "parameters": { "respondWith": "json", "responseBody": "={{ JSON.stringify($json) }}", "options": { "responseCode": "={{ $json.status_code }}" } }, "id": "n9", "name": "Return the error as JSON", "type": "n8n-nodes-base.respondToWebhook", "typeVersion": 1.1, "position": [ 2000, 180 ] } ], "connections": { "Receive invoice data": { "main": [ [ { "node": "Set your company details", "type": "main", "index": 0 } ] ] }, "Set your company details": { "main": [ [ { "node": "Check the request is complete", "type": "main", "index": 0 } ] ] }, "Check the request is complete": { "main": [ [ { "node": "Calculate line totals and VAT", "type": "main", "index": 0 } ], [ { "node": "Explain what went wrong", "type": "main", "index": 0 } ] ] }, "Calculate line totals and VAT": { "main": [ [ { "node": "Render the invoice as PDF", "type": "main", "index": 0 } ] ] }, "Render the invoice as PDF": { "main": [ [ { "node": "Did the render succeed?", "type": "main", "index": 0 } ] ] }, "Did the render succeed?": { "main": [ [ { "node": "Return the PDF", "type": "main", "index": 0 } ], [ { "node": "Explain what went wrong", "type": "main", "index": 0 } ] ] }, "Explain what went wrong": { "main": [ [ { "node": "Return the error as JSON", "type": "main", "index": 0 } ] ] } }, "settings": { "executionOrder": "v1" }, "pinData": {} }