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Problems setting up simple test project - Exceljs and Browserify


I'm trying to set up a simple test project to test ExcelJS via a browser application, and for the life of me I can not get Browserify to work properly.

I bundle my code into a bundle file with the appropriate require calls and the resulting bundle throws the following error when the page is loaded:

Uncaught TypeError: Cannot read property 'prototype' of undefined

This error appears to be thrown on an fs.ReadStream method?

Here is my code:

index.html

<!DOCTYPE html>
<head>
  <title>Test Excel JS</title>
  <meta charset="utf-8">
  <meta name="description" content="">

  <link rel="stylesheet" href="app.css">
</head>
<body>
  <div>
    <label>Test</label>
    <button onclick="test()">Test this Stuff and Check your console log</button>
  </div>

  <script src="bundle.js"></script>
  <script>
      var test = function(){
          var workbook = generateTestFile();
          console.log(workbook);
      };
  </script>
</body>
</html>

app.js (base for bundle.js)

'use strict';

var Excel = require('exceljs');

var isBold = function(dataRow){
    return dataRow.name === "Jeff";
};

var getRowColor = function(dataRow){
    return dataRow.color;
};

var getCellColor = function(dataRow, cell){
    return (dataRow.name === 'John' && cell.value === 0)? 'orange' : dataRow.color;
};

var getFont = function(isBold, color){
    return {
        name: 'Arial Black',
        color: color,
        family: 2,
        size: 14,
        bold: isBold
    };
};

var getTestHeader = function(){
    return [
        {key: "id", header: "Id"},
        {key: "name", header: "Name", width: 32},
        {key: "color", header: "Color", width: 10}
    ];
};

var getTestData = function(){
    return [
        {
            id: 0,
            name: "John",
            color: "green"
        },
        {
            id: 1,
            name: "Rehan",
            color: "blue"
        },
        {
            id: 2,
            name: "Jeff",
            color: "yellow"
        }
    ];
};

var generateTestFile = function(){
    var workbook = new Excel.Workbook();
    var worksheet = workbook.addWorksheet('Sheet 1');

    //Set Column Headers
    worksheet.columns = getTestHeader();

    //Add Rows
    var testData = getTestData();
    var length = testData.length;
    for(var i = 0; i < length; i++){
        worksheet.addRow(testData[i]);
    }

    //Format Rows
    worksheet.eachRow(function(row, rowNumber){
        console.log(row);
        var isBold = isBold(row);
        var rowColor = getRowcolor(row);
        row.eachCell(function(cell, colNumber){
            var cellColor = getCellColor(row, cell);
            console.log(cell);
        });
    });

    return workbook;
};

How do I get this to work? All I really want to do is test excelJS. I don't care what the solution is, as long as I can verify that the library works, I'll be happy.


Solution

  • You should browserify exceljs/dist/es5/exceljs.browser instead of exceljs

    var Excel = require('exceljs/dist/es5/exceljs.browser');
    

    Since you are going to browserify your app.js you should make your functions (variables) visible in global scope (window)

    global.generateTestFile = function generateTestFile(){
        // ...
    };
    

    You can not declare a variable with name isBold and call function expression isBold at the same time, because your var keyword will declare a variable isBold in current scope and your function will not be available (See var). So comment it out, since it is not used in your code:

    //var isBold = isBold(row);
    

    Also, there is a typo in getRowcolor. Fix it:

    var rowColor = getRowСolor(row);
    

    Here is the gulpfile.js for you:

    var gulp = require('gulp');
    var source = require('vinyl-source-stream');
    var browserify = require('browserify');
    //var uglify = require('gulp-uglify');
    //var buffer = require('vinyl-buffer');
    
    gulp.task('default', function() {
      return browserify('app.js')
        .bundle()
        .pipe(source('bundle.js'))
        //.pipe(buffer())
        //.pipe(uglify())
        .pipe(gulp.dest('.'));
    });
    

    You can also browserify exceljs/dist/es5/exceljs.browser.js itself and use it in your app.