It seems that the code works but doesn\u2019t scale too well.<\/p>\n\n\n\n
It\u2019s possible that by performing all operations in parallel, javascript\u2019s Garbage Collection (GC) isn\u2019t given the opportunity to clear intermediate objects, and an oversized heap causes the crash.<\/p>\n\n\n\n
Performing the operations in series may have a positive effect. The code is simply derived from the code in the question.<\/p>\n\n\n\n
First, an adaptor function, which promisifies Now call html2canvas()<\/code> :<\/p>\n\n\n\nfunction html2canvasAsync(element) {\n return new Promise(function(resolve, reject) {\n html2canvas(element, {\n onrendered: function (canvas) {\n resolve(canvas.toDataURL('image\/png'));\n }\n });\n });\n};<\/pre><\/div>\n\n\n\ndivNamesForPDF.reduce(\u2026)<\/code> to serialize the asynchronous operations and progressively add to the jsPDF doc<\/code> :<\/p>\n\n\n\nfunction GeneratePDFforCharts(divNamesForPDF) {\n if (window.Promise) {\n var doc = new jsPDF('l', 'mm', [297, 210], true); \/\/true is set for pdf compression\n return divNamesForPDF.reduce(function(p, name, i) {\n return p.then(function(pageNumber) {\n return html2canvasAsync($(name).get(0)) \/\/ or `document.getElementById(name)` ?\n \/\/ return html2canvasAsync(document.getElementById(name)) \/\/ possibly?\n .then(function(canvas) {\n if (isOdd(i)) { \/\/ odds\n doc.addImage(canvas, 'PNG', 10, 105, 270, 100, null, 'FAST'); \/\/x, y, width, height - FAST is used for png compression\n doc.text(140, 207, pageNumber.toString()); \/\/x, y, text\n pageNumber++;\n } else { \/\/ evens\n if (i > 0) {\n doc.addPage();\n }\n doc.addImage(canvas, 'PNG', 10, 5, 270, 100, null, 'FAST');\n }\n return pageNumber;\n }).catch(function(e) {\n \/\/ Error handling is a good idea\n console.log(e);\n doc.text(35, 25, e.message); \/\/ possibly add the error message to doc\n });\n });\n }, Promise.resolve(1)) \/\/ starter promise resolved with page number 1\n .then(function() {\n doc.save('IEA_Global_MonthlyStocks_Analytics.pdf');\n });\n }\n}<\/pre><\/div>\n","protected":false},"excerpt":{"rendered":"