Automatisierte Rechnungssammlung und Datenextraktion mit Vision API und LLM

• •Telegram Bot Token
• •Google Drive API-Anmeldedaten
• •Möglicherweise sind Ziel-API-Anmeldedaten erforderlich
• •Google Sheets API-Anmeldedaten

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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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            "TRANSACTION DETAIL": "={{ $json.output['TRANSACTION DETAIL'] }}"
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          "mode": "list",
          "value": "gid=0"
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        "documentId": {
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          "value": "YOUR_GOOGLE_SHEETS_DOCUMENT_ID"
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      "name": "Bei Formularübermittlung",
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              "fieldLabel": "Image",
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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."
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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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        "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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    }
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