Node.js Receipt OCR

onst axios = require('axios');
const fs = require('fs');
const FormData = require('form-data');

// Specify variables for use in script below
const apiBaseUrl = 'https://app.butlerlabs.ai/api';

// Make sure to add the API Key you wrote down above to the auth headers
const apiKey = 'MY_API_KEY';
const authHeaders = {
  'Authorization': 'Bearer ' + apiKey
};

// Use the Queue API Id you grabbed earlier
const queueId = 'MY_QUEUE_ID';

// Specify the path to the file you would like to process
const localFilePaths = ['/path/to/file'];

// Specify the API URL
const uploadUrl = apiBaseUrl + '/queues/' + queueId + '/uploads';

// This async function uploads the files passed to it and returns the id
// needed for fetching results.
// It is used in our main execution function below
const uploadFiles = async (filePaths) => {
  // Prepare file for upload
  const formData = new FormData();
  filePaths.forEach((filePath) => {
    formData.append('files', fs.createReadStream(filePath));
  });

  // Upload files to the upload API
  console.log('Uploding files to Butler for processing');
  const uploadResponse = await axios.post(
    uploadUrl,
    formData,
    {
      headers: {
        ...authHeaders,
        ...formData.getHeaders(),
      }
    })
    .catch((err) => console.log(err));

  // Return the Upload ID
  return uploadResponse.data.uploadId;
}

// This async function polls every 5 seconds for the extraction results using the
// upload id provided and returns the results once ready
const getExtractionResults = async (uploadId) => {
  // URL to fetch the result
  const extractionResultsUrl = apiBaseUrl + '/queues/' + queueId + '/extraction_results';
  const params = { uploadId };

  // Simple helper function for use while polling on results
  const sleep = (waitTimeInMs) => new Promise(resolve => setTimeout(resolve, waitTimeInMs));

  // Make sure to poll every few seconds for results.
  // For smaller documents this will typically take only a few seconds
  let extractionResults = null;
  while (!extractionResults) {
    console.log('Fetching extraction results');
    const resultApiResponse = await axios.get(
      extractionResultsUrl,
      { headers: { ...authHeaders }, params, }
    );

    const firstDocument = resultApiResponse.data.items[0];
    const extractionStatus = firstDocument.documentStatus;
    // If extraction has not yet completed, sleep for 5 seconds
    if (extractionStatus !== 'Completed') {
      console.log('Extraction still in progress. Sleeping for 5 seconds...');
      await sleep(5 * 1000);
    } else {
      console.log('Extraction results ready');
      return resultApiResponse.data;
    }
  }
}

// Use the main function to run our entire script
const main = async () => {
  // Upload Files
  const uploadId = await uploadFiles(localFilePaths);
  // Get the extraction results
  const extractionResults = await getExtractionResults(uploadId);

  // Print out the extraction results for each document
  extractionResults.items.forEach(documentResult => {
    const fileName = documentResult.fileName;
    console.log('Extraction results from ' + fileName);

    // Print out each field name and extracted value
    console.log('Fields')
    documentResult.formFields.forEach(field => {
      const fieldName = field.fieldName;
      const extractedValue = field.value;

      console.log(fieldName + ' : ' + extractedValue);
    });

    // Print out the results of each table
    console.log('\n\nTables');
    documentResult.tables.forEach(table => {
      console.log('Table name: ' + table.tableName);
      table.rows.forEach((row, idx) => {
        let rowResults = 'Row ' + idx + ': \n';
        row.cells.forEach(cell => {
          // Add each cells name and extracted value to the row results
          rowResults += cell.columnName + ': ' + cell.value + ' \n';
        });

        console.log(rowResults);
      });
    });
  });
}

main();

{
  "documentId": "cccffe8e-d621-455a-9f2f-f977db21a215",
  "documentStatus": "Completed",
  "fileName": "receipt_2.png",
  "mimeType": "image/png",
  "documentType": "Receipt",
  "confidenceScore": "High",
  "formFields": [
    {
      "fieldName": "Merchant Name",
      "value": "OSCAR'S MEXICAN SEAFOOD",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Merchant Address",
      "value": "927 J Street San Diego, Ca. 92101",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Merchant Phone Number",
      "value": "619-564-6007",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Transaction Date",
      "value": "6/05/18",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Transaction Time",
      "value": "12:42pm",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Subtotal",
      "value": "10.55",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Tax",
      "value": "0.82",
      "confidenceScore": "High"
    },
    {
      "fieldName": "Total",
      "value": "11.37",
      "confidenceScore": "High"
    }
  ],
  "tables": [
    {
      "tableName": "Items",
      "confidenceScore": "Low",
      "rows": [
        {
          "cells": [
            {
              "columnName": "Item Name",
              "confidenceScore": "High",
              "value": "Bottle Water"
            },
            {
              "columnName": "Quantity",
              "confidenceScore": "High",
              "value": "1"
            },
            {
              "columnName": "Total Price",
              "confidenceScore": "High",
              "value": "1.25"
            }
          ]
        },
      ]
    }
  ]
}