Colección automatizada de facturas y extracción de datos con Vision API y LLM

• •Bot Token de Telegram
• •Credenciales de API de Google Drive
• •Pueden requerirse credenciales de autenticación para la API de destino
• •Credenciales de API de Google Sheets

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  "name": "Automated Invoice Collection & Data Extraction Using Vision API and LLM",
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        "content": "# Automated Invoice Collection & Data Extraction Using Vision API and LLM\n\nThis workflow automates the process of collecting uploaded invoices, extracting text using **Google Vision API**, and processing the extracted text with an LLM to produce structured data containing key transaction details such as **date, voucher number, transaction detail, vendor, and transaction value**.  \nThe final data is saved to **Google Sheets** and a notification is sent to **Telegram** in real time.\n\n## ✨ Key Features\n- **Invoice Upload Form**  \n  Users can upload invoice images through a provided form.\n- **Google Drive Integration**  \n  Files are stored in a specified Google Drive folder with a shareable preview link.\n- **OCR via Google Vision API**  \n  Converts invoice images to text using `TEXT_DETECTION`.\n- **Data Structuring via LLM**  \n  Uses LLM model to parse and structure data.\n- **Structured Output Parser**  \n  Ensures consistent output with required columns.\n- **Data Cleaning**  \n  Cleans and formats numeric values without currency symbols.\n- **Google Sheets Sync**  \n  Appends or updates transaction data in Google Sheets (matched by file ID).  \n  **Template:** [Google Sheets](https://docs.google.com/spreadsheets/d/1HMzQtFK9T-GDxGFSD7ErW_QLlq-PvCvoFASiHGG2fGM/edit?gid=0#gid=0)\n- **Telegram Notification**  \n  Sends a transaction summary directly to a Telegram chat/group.\n\n---\n\n## 🔐 Required Credentials\n- **Google Vision API Key** → for OCR processing.  \n- **OpenRouter API Key** → to access the Gemini Flash LLM.  \n- **Google Drive OAuth2** → to upload and download invoice files.  \n- **Google Sheets OAuth2** → to write or update spreadsheet data.  \n- **Telegram Bot Token** → to send notifications to Telegram.  \n- **Telegram Chat ID** → target chat/group for notifications.\n\n---\n\n## 🎁 Benefits\n- **Fully automated** from invoice upload to structured reporting.\n- **Time-saving** by eliminating manual transaction data entry.\n- **Real-time integration** with Google Sheets for reporting and auditing.\n- **Instant notifications** via Telegram for quick transaction monitoring.\n- **Duplicate prevention** using file ID as a matching key.\n- **Flexible** for accounting, finance, or administrative teams.\n"
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        "text": "={{ $json.responses[0].fullTextAnnotation.text }}",
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        "messages": {
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              "message": "=You are a professional accountant experienced in preparing financial reports and classifying expenses into appropriate categories.\nYou will receive input data extracted via OCR that needs to be parsed and structured.\n\nInstructions:\n\nOutput must be in the same language as the input.\nParse and return the data in this column order:\nDATE : Extract in YYYY-MM-DD format, if not found use current date\nNO VOUCHER : Extract invoice or voucher number, if not found return not found\nTRANSACTION DETAIL : Short summary of products or services, if not found return not found\nVENDOR : Store or vendor name, if not found return not found\nVALUE : Transaction total amount as a number without currency symbol, if not found return 0\n\nMissing text fields : not found\nMissing numeric values : 0\nOutput only the structured data, no extra explanations"
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      "typeVersion": 1
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        "jsonSchemaExample": "{\n  \"DATE\": \"2025-07-07\",\n  \"NO VOUCHER\": \"INV-001234\",\n  \"TRANSACTION DETAIL\": \"Product summary\",\n  \"VENDOR\": \"Vendor Name or Shop Name\",\n  \"VALUE\": 0\n}"
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          "mode": "id",
          "value": "={{ $json.id }}"
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        "operation": "download"
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        "jsonBody": "={\n  \"requests\": [\n    {\n      \"image\": {\n        \"content\": \"{{ $('Code').item.json.base64 }}\"\n      },\n      \"features\": [\n        {\n          \"type\": \"TEXT_DETECTION\"\n        }\n      ]\n    }\n  ]\n}\n",
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        "text": "=💳 New transaction : \n- Date : {{ $json.DATE }}\n- Transaction detail : {{ $json['TRANSACTION DETAIL'] }}\n- Vendor : {{ $json.VENDOR }}\n- Total transaction : {{ $json.VALUE }}\n\n---",
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        "name": "={{ $json.Image[0].filename }}",
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          "value": "My Drive"
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        "folderId": {
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          "mode": "list",
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        "jsCode": "function cleanNumber(n) {\n  return parseInt(n.toString().replace(/[.,]/g, '')) || 0;\n}\n\n// Get output from $json\nconst output = $json.output || {};\n\n// If there are Items, process them. If not, skip.\nconst items = Array.isArray(output.Items)\n  ? output.Items.map(item => ({\n      ...item,\n      Quantity: cleanNumber(item.Quantity),\n      \"Unit Price\": cleanNumber(item[\"Unit Price\"]),\n      Total: cleanNumber(item.Total),\n    }))\n  : undefined;\n\n// Optional: clean Total Amount as well\nconst totalAmount = output[\"Total Amount\"]\n  ? cleanNumber(output[\"Total Amount\"])\n  : 0;\n\nreturn {\n  json: {\n    output: {\n      ...output,\n      ...(items && { Items: items }),\n      \"Total Amount\": totalAmount,\n    }\n  }\n};\n"
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            "DATE": "={{ $json.output.DATE }}",
            "VALUE": "={{ $json.output.VALUE }}",
            "VENDOR": "={{ $json.output.VENDOR }}",
            "FILE NAME": "={{ $('Download file').item.json.name }}",
            "NO VOUCHER": "={{ $json.output['NO VOUCHER'] }}",
            "TRANSACTION DETAIL": "={{ $json.output['TRANSACTION DETAIL'] }}"
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              "displayName": "DATE",
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              "canBeUsedToMatch": true
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              "displayName": "NO VOUCHER",
              "defaultMatch": false,
              "canBeUsedToMatch": true
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              "required": false,
              "displayName": "TRANSACTION DETAIL",
              "defaultMatch": false,
              "canBeUsedToMatch": true
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              "displayName": "VENDOR",
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              "canBeUsedToMatch": true
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              "displayName": "VALUE",
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          "mappingMode": "defineBelow",
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          "attemptToConvertTypes": false,
          "convertFieldsToString": false
        },
        "options": {},
        "operation": "appendOrUpdate",
        "sheetName": {
          "__rl": true,
          "mode": "list",
          "value": "gid=0"
        },
        "documentId": {
          "__rl": true,
          "mode": "list",
          "value": "YOUR_GOOGLE_SHEETS_DOCUMENT_ID"
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        "formFields": {
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              "fieldType": "file",
              "fieldLabel": "Image",
              "requiredField": true,
              "acceptFileTypes": ".jpg, .png, .jpeg"
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        "content": "- This node triggers the workflow when a user submits a form titled \"Upload Purchase Invoice\".\n- Uploads the file received from the form into a specific Google Drive folder.\n- Downloads the file from Google Drive using the file ID obtained from the previous Upload file node."
      },
      "typeVersion": 1
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        "content": "- Converts the downloaded invoice file (binary) into Base64 format so that it can be sent to the Google Vision API.\n- Adds the Google Vision API key into the workflow data so it can be used in the HTTP request.\n- Sends the Base64-encoded image to the Google Vision API for OCR processing."
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        "content": "- Processes OCR text through an LLM to extract and structure key invoice details.\n- Forces the LLM to produce output in a fixed JSON schema.\n- Cleans and normalizes numeric fields from the LLM output."
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        "width": 380,
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        "content": "- Writes the extracted and cleaned invoice data into a Google Sheets document, either adding a new row or updating an existing one.\n- Sends a Telegram message summarizing the new or updated transaction entry."
      },
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