{ "name": "PolyDoc - Website change monitor (screenshot on change)", "nodes": [ { "id": "d1111111-1111-4111-8111-111111111111", "name": "Every 6 hours", "type": "n8n-nodes-base.scheduleTrigger", "position": [ 240, 320 ], "parameters": { "rule": { "interval": [ { "field": "hours", "hoursInterval": 6 } ] } }, "typeVersion": 1.2 }, { "id": "d2222222-2222-4222-8222-222222222222", "name": "Settings", "type": "n8n-nodes-base.set", "position": [ 440, 320 ], "parameters": { "options": {}, "assignments": { "assignments": [ { "id": "set-url", "name": "url", "type": "string", "value": "https://example.com" } ] } }, "typeVersion": 3.4 }, { "id": "d3333333-3333-4333-8333-333333333333", "name": "Fetch page", "type": "n8n-nodes-base.httpRequest", "position": [ 640, 320 ], "parameters": { "url": "={{ $json.url }}", "method": "GET", "options": {} }, "typeVersion": 4.2 }, { "id": "d4444444-4444-4444-8444-444444444444", "name": "Detect change", "type": "n8n-nodes-base.code", "position": [ 840, 320 ], "parameters": { "mode": "runOnceForAllItems", "jsCode": " const res = $input.first().json;\n const html = res.data ?? (typeof res === 'string' ? res : JSON.stringify(res));\n const normalized = String(html)\n .replace(//gi, '')\n .replace(//gi, '')\n .replace(//g, '')\n .replace(/\\s+/g, ' ')\n .trim();\n\n // djb2-xor hash: no imports, works in the sandboxed Code node.\n let hash = 5381;\n for (let i = 0; i < normalized.length; i++) {\n hash = ((hash * 33) ^ normalized.charCodeAt(i)) >>> 0;\n }\n const current = String(hash);\n\n const store = $getWorkflowStaticData('global');\n const previous = store.lastHash;\n store.lastHash = current;\n\n return [\n {\n json: {\n url: $('Settings').first().json.url,\n changed: previous !== current,\n firstRun: previous === undefined,\n previousHash: previous ?? null,\n currentHash: current,\n },\n },\n ];" }, "typeVersion": 2 }, { "id": "d5555555-5555-4555-8555-555555555555", "name": "Changed?", "type": "n8n-nodes-base.if", "position": [ 1040, 320 ], "parameters": { "options": {}, "conditions": { "options": { "version": 2, "leftValue": "", "caseSensitive": true, "typeValidation": "loose" }, "combinator": "and", "conditions": [ { "id": "cond-changed", "operator": { "type": "boolean", "operation": "true", "singleValue": true }, "leftValue": "={{ $json.changed }}", "rightValue": "" } ] } }, "typeVersion": 2.2 }, { "id": "d6666666-6666-4666-8666-666666666666", "name": "Screenshot page", "type": "n8n-nodes-polydoc.polyDoc", "position": [ 1280, 320 ], "parameters": { "url": "={{ $json.url }}", "operation": "screenshot", "sourceType": "url", "deliveryMode": "download", "additionalFields": { "filename": "snapshot.png" }, "screenshotOptions": { "fullPage": true, "imageType": "png", "viewportWidth": 1280, "viewportHeight": 800 }, "binaryPropertyName": "data" }, "typeVersion": 1 }, { "id": "d7777777-7777-4777-8777-777777777777", "name": "Email screenshot", "type": "n8n-nodes-base.emailSend", "position": [ 1480, 320 ], "parameters": { "text": "=The watched page changed since the last check.\n\nURL: {{ $('Detect change').first().json.url }}\n\nThe current full-page screenshot is attached.", "options": { "attachments": "data" }, "subject": "=Change detected: {{ $('Detect change').first().json.url }}", "toEmail": "you@example.com", "fromEmail": "user@example.com", "emailFormat": "text" }, "typeVersion": 2.1 }, { "id": "d8888888-8888-4888-8888-888888888888", "name": "No change", "type": "n8n-nodes-base.noOp", "position": [ 1280, 700 ], "parameters": {}, "typeVersion": 1 }, { "id": "d9999999-9999-4999-8999-999999999999", "name": "Read me first", "type": "n8n-nodes-base.stickyNote", "position": [ 200, -260 ], "parameters": { "width": 1380, "height": 360, "content": "## Website change monitor with screenshots\n\n**What it does:** Polls a web page on a schedule, detects whether its content changed since the last run, and captures a full-page PolyDoc screenshot **only when it changed**, so you never spend a screenshot on an unchanged page. The snapshot is emailed to you.\n\n**Who it's for:** Anyone tracking competitor pages, pricing, docs, or status pages who wants a visual record of every change.\n\n### Setup\n1. Set the **url** to watch in the *Settings* node.\n2. Add your **PolyDoc API** credential on *Screenshot page* (free key at dashboard.polydoc.tech).\n3. Add an **SMTP** credential on *Email screenshot*, or swap it for Slack / S3 / Google Drive.\n\nStart free: https://polydoc.tech" }, "typeVersion": 1 }, { "id": "da111111-1111-4111-8111-111111111111", "name": "Section: Watch", "type": "n8n-nodes-base.stickyNote", "position": [ 200, 180 ], "parameters": { "color": 4, "width": 400, "height": 260, "content": "## 1. Watch on a schedule\n\nRuns every 6 hours. The URL to watch lives in **Settings**, so you edit it in one place." }, "typeVersion": 1 }, { "id": "db222222-2222-4222-8222-222222222222", "name": "Section: Detect", "type": "n8n-nodes-base.stickyNote", "position": [ 620, 180 ], "parameters": { "color": 4, "width": 620, "height": 260, "content": "## 2. Detect a real change\n\nFetch the page, strip scripts, styles and whitespace, hash it, and compare to the last run (stored in workflow static data). Only a genuine content change continues." }, "typeVersion": 1 }, { "id": "dc333333-3333-4333-8333-333333333333", "name": "Section: Capture", "type": "n8n-nodes-base.stickyNote", "position": [ 1260, 180 ], "parameters": { "color": 4, "width": 420, "height": 260, "content": "## 3. Capture & send\n\nPolyDoc renders a full-page PNG of the changed page, which is emailed as an attachment." }, "typeVersion": 1 }, { "id": "de555555-5555-4555-8555-555555555555", "name": "Setup: URL", "type": "n8n-nodes-base.stickyNote", "position": [ 400, 470 ], "parameters": { "color": 7, "width": 180, "height": 110, "content": "**Set the URL** you want to watch here." }, "typeVersion": 1 }, { "id": "df666666-6666-4666-8666-666666666666", "name": "Note: first run", "type": "n8n-nodes-base.stickyNote", "position": [ 660, 470 ], "parameters": { "color": 7, "width": 380, "height": 130, "content": "First run and every manual test count as a change, so the screenshot branch runs right away. State then persists between scheduled runs." }, "typeVersion": 1 }, { "id": "e0777777-7777-4777-8777-777777777777", "name": "Setup: PolyDoc key", "type": "n8n-nodes-base.stickyNote", "position": [ 1240, 470 ], "parameters": { "color": 7, "width": 190, "height": 110, "content": "**Add your PolyDoc API credential.** Free key at dashboard.polydoc.tech" }, "typeVersion": 1 }, { "id": "e1888888-8888-4888-8888-888888888888", "name": "Setup: email", "type": "n8n-nodes-base.stickyNote", "position": [ 1450, 470 ], "parameters": { "color": 7, "width": 210, "height": 110, "content": "**Add an SMTP credential**, or swap this node for Slack / S3 / Google Drive." }, "typeVersion": 1 }, { "id": "e2999999-9999-4999-8999-999999999999", "name": "Note: no change", "type": "n8n-nodes-base.stickyNote", "position": [ 1420, 700 ], "parameters": { "color": 7, "width": 250, "height": 110, "content": "**Nothing changed.** No screenshot is taken, the run ends quietly." }, "typeVersion": 1 } ], "active": false, "settings": { "executionOrder": "v1" }, "connections": { "Changed?": { "main": [ [ { "node": "Screenshot page", "type": "main", "index": 0 } ], [ { "node": "No change", "type": "main", "index": 0 } ] ] }, "Settings": { "main": [ [ { "node": "Fetch page", "type": "main", "index": 0 } ] ] }, "Fetch page": { "main": [ [ { "node": "Detect change", "type": "main", "index": 0 } ] ] }, "Detect change": { "main": [ [ { "node": "Changed?", "type": "main", "index": 0 } ] ] }, "Every 6 hours": { "main": [ [ { "node": "Settings", "type": "main", "index": 0 } ] ] }, "Screenshot page": { "main": [ [ { "node": "Email screenshot", "type": "main", "index": 0 } ] ] } } }