How to take a screenost of rendered html to create a png? - node.js

I need to dynamically generate images containing a persons photo and various bits of 'status' information. I have some designs from our designer.
Looking at the designs the easiest way (for me) would be to generate that look using the tools I know - HTML, CSS, ReactJs etc.
But how can I essentially 'take a screenshot' (on the server) of what the browser would see and then save that out to a PNG?
Ideally I'd like to do this in nodejs but happy to consider c# or java or other languages if need be.
I know that nodejs will let you run a 'headless browser' for testing but what I want to do is essentially 'take a visual snapshot' of what those browsers 'see' and save to a png?
Keen to write this and run it on our server so looking for suggestions involving how I could code this up rather than an external service, if possible.
Thanks in advance!

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Google Docs: Table of content page numbers

we are currently building an application on the google cloud platform, which generates reports in Google Doc. For them, it is really important to have a table of content ... with page numbers. I know this is a feature request since a few years and there are add-ons (Paragraph Styles +, which didn't work for us) that provide this solution, butt we are considering to build this ourselves. if anybody has a suggestion on how we could start with this, it would be a great help!
thanks,
Best bet is to file a feature request on the product forums.
Currently the only way to do that level of manipulation of a doc to provide a custom TOC is to use Apps Script. It provides access to the document structure sufficient enough to build and insert a basic table of contents, but I'm not sure there's enough to do paging correctly (unless you force a page break on ever page...) There's no method to answer the question of "what page is this element on?"
Hacks like writing to a DOCX and converting don't work because TOCs are recognized for what they and show up without page numbers.
Of course you could write a DOCX or PDF with the TOC as you'd like and upload as a blob rather than as a Google Doc. They can still be viewed in Drive and such.

Obfuscate Images in EaselJS

Is there any way to protect your sprites on EaselJS?
Currently is too easy to download the sprites.
On chrome just go to console -> resources like this
I made a resarch before i made this answer and found this topic .
That could be very nice. Also we don't need to save the slices in a json like he said, if we have a shuffle seed.
But, i didn't find any thing in nodejs(back-end) to make this image shuffle.
I tried Node GM but its looks too complicaded to bind a image on top of another with (w,h,x,y,offsetX,offsetY)
I know always will have a way to "hack" the resource. But at least offer some difficult.
One of the simple approaches is to encode images to base64, store them as part of Javascript and decode at runtime. See:
Convert and insert Base64 data to Canvas in Javascript
But obviously this will increase download size.
Personally, I would not go this route for "normal" applications or games, unless it is really justified or put on me as an external requirement. For example, one can easily extract assets from the android APK, but this does not seem an area of concern for most of the developers.
The user's browser downloads those images whether you want it or not. Otherwise, they wouldn't be able to display them.
At any given time, any user can just right click on any image on the site and click SAVE AS, you can't stop it, and you shouldn't try.
If you don't want people downloading your work, don't put it on the public facing internet.

How to validate HTML Reports using Watir

We are trying to validate the HTML reports generated by our application. We have planned the below approach to do this
Capture that data related to the report from application
Generate the report
Identify the report’s elements and compare the data captured from application against the data/elements in report.
We started with identification of elements of the report and found that using 'Developers tool' we are able get some of the object properties where the Object ID is missing from these properties.
Can anyone please let us know the possibility of capturing the report elements and comparing them with the application data.
Frankly if you are just trying to parse HTML, and not trying to drive a browser, you'd probably be better off using something like Nokogiri, or another library aimed specifically at parsing HTML See https://www.ruby-toolbox.com/categories/html_parsing for a selection of such tools
Watir is 'Web Application Testing In Ruby" it is designed to drive web-browsers, in order to test websites and webapps. Validation that portions of the HTML are as expected is a part of that, but not the core functionality of Watir.
For what you are trying to do, if I understand you right, you could use watir to do that, in somewhat the same way you can use excel for word processing and page layout, which is to say it can be done, but may not be the most preferred tool or easiest way to go about it.

How to add text to any html element?

I want to add text to body element but I don't know how. Which method will work on the body tag?
Sorry for my english and thanks for replies.
In Watir, you can manipulate a web page (DOM) using JS, just like that:
browser.execute_script("document.getElementById('pageContent').appendChild(document.createTextNode('Great Success!'));")
I assume that the point of the question is:
All users are not just interacting by just clicking buttons and links on the web app, some of them are doing nasty things like altering http requests to make your system do something that it is not supposed to do... or to just have some fun.
To mimic this behavior, you could write a ui-test that alters forms on the web page, so that for example, one could type in anything into any field instead of a limited dropdown.
To do that, ui test has to:
manipulate DOM to set form inputs free of limitations (replace select's with input's, etc.)
ui test has to know, which values to use, in many cases it's pointless to enter random values. Your webapp has to provide some good "unwanted" options.
Why would you want to modify the webpage in Watir? It's for automated testing, not DOM manipulation.
If you want to add something to the DOM element in javascript, you can do it like that:
var txt = document.createTextNode(" This text was added to the DIV.");
document.getElementById('myDiv').appendChild(txt);
Or use some DOM manipulation library, like jQuery.
If you have not worked your way though the watir tutorial, I would suggest you do so. It deals with things like filling in text fields etc.
Learn to use the developer tools for your browser, Firebug for Firefox, or the built in tools for IE and CHrome. They will let you look at things as you interact with the site.
If the element is not a normal HTML input field of some sort, then you are dealing with a custom control. Many exist and they are varied and there is no one set solution for dealing with them. Without knowing which control you are using, and being able ourselves to interact with a sample of it, or at least see the HTML, it is very very difficult to advise you, we basically have to just guess (which is often a waste of everyone's time)
Odds are if you have a place you can enter text, then it is some form of input control, it might not start out that way, you may need to click on some other element, to make the input area appear, but without a sample of HTML all we can do is guess.
If this is a commercial control, see if you can find a demo site that shows the control in action. Try googling things like class names for the elements and often you get lucky

Creating PDF Invoices - Are there any templating solutions? [closed]

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Our company is looking to integrate invoices into a new system we are developing.
We require a solution to create a layout of the invoice and then convert to pdf.
We have considered just laying out the invoice in html/css then converting to pdf.
We have also considered using SVG->PDf conversion.
Both of these solutions integrate well into our existing templating language used for our web application.
Historically we have been a Microsoft based business and used Crystal Reports for such a task but we are looking for an open source Linux solution for this project.
Does any one have any suggestions of an approach or technology we could use for such a task?
Try this... create a blank invoice with Word (or whatever you want) and save it as a PDF.
Then use a PDF library to modify the PDF (insert the text at particular coordinates). We do this in the Microsoft world and it is extremely easy.
The biggest benefit is that we can use our own tools to create and modify the template. If we want to add some static text, we just crank open Word, make the change and save it to a PDF file (that is being used as a template).
For Microsoft, we use iTextSharp which is actually a C# port of the original Java version of iText
Additionally...
You can use Adobe Acrobat to insert fields in the PDF (address, phone, invoice number, line item 1, line item 2, etc...) and then use iText/iTextSharp to populate these fields at run time.
This is, in more detail, what we do... and it is extremely easy.
The normal way is to install (La)TeX (probably already on the linux box) and run pdflatex to get the pdfs. You can also use Apache FOP, if you prefer xslt and xsl-fo.
If the number of invoices to create is low you might want to use open-office (directly or as a toolkit).
If you want high-precision positioning and low-level access, a low-level pdf library (I don't know if iTextSharp works with mono) might be what you want.
I would try out LaTeX first, because it allows you to get results with the least effort.
I've previously produced invoices by templating a PostScript file, and then using Ghostscript's ps2pdf to convert those into PDFs.
We use Reportlab with Python. If you look around there are a load of ready-made forms/invoices/etc.
There are several OSS reporting engines (Jasper Reports, Pentaho and BIRT to name three) that you could use in much the same way as you have historically used Crystal Reports. One of the other posters mentions ReportLab, which is an option if you're using Python or can embed a Python runtime in your application.
Probably the most flexible solution is to create XMLs with invoice data and then by using XSLTs transform the, into PDFs, HTMls, whatever...
It depends on your environment. If you have access to Java, you might look at iText (http://www.lowagie.com/iText/), a library that allows you to generate PDF files on the fly.
There are two steps, if i understood correctly:
1) Creation of PDF template with placeholders to populate data programmatically
2) Populating the PDF template programmatically during run time
For #1, OpenOffice allows creation of PDF templates, which can then be populated programmatically. It's good enough to create simple invoices that doesn't probably involve datagrid/table kind of stuff.
For #2, you already have the answers here - iText, iTextSharp.
Hope this helps!
I love wkhtmltopdf http://code.google.com/p/wkhtmltopdf/
Not sure what your goal is here, but there is an opensource php-library called fpdf, which also has an extension for taking a pre-made pdf as layout and then populate it with more content, generating a new PDF with that info.
However, I would go for a solution that you can integrate nicely into the plattform you're building, but I wouldn't go in a HTML->PDF solution since you won't have any clue about what would fit on a piece of paper regarding sizes in that kind of enviroment, meaning you won't know when you should split the content into two separate templates.
You might also try using XSL:FO. XSL:FO is a documented standard for describing page layout: http://www.w3.org/TR/xsl/#fo-section.
I've had success on two projects creating documents by creating an XML schema that defines the content of the "PDF". I then use the XSD tool (from Microsoft) to generate a class representing this document. I then map my data into that structure, serialize the populated class to XML, along with an XSL stylesheet that defines how that data should be mapped into FO, and pass it to an FO formatter. For formatters, I have use Alt-Soft's Xml2Pdf with success. There are a few others out there. There are some tools available to help create the XSL to FO stylesheet (i.e. stylusstudio and XmlSpy), but I recommend learning the FO constructs as the tools seem to produce bloated stylesheets. FO is comparable to HTML (where a P tag is a BLOCK tag in FO), but can be tricky. This nice thing about FO, is that some formatter support conversion to other formats, such as Word, HTML, etc.
Other options:
iTextSharp (C# port of iText). Just started reading about this. Open source and free. I don't think there is any "templating" supported with this, but I could be wrong about that.
SQL Server Reporting Services. Assuming your invoice data is in, or can be put in, a format that can be read by reporting services (SQL Server, Web Service, etc), define the layout in SSRS and then publish to reporting server. Use SSRS Web Services or query parameter execution to execute the report and have it output as PDF.
This html-2-pdf site may be a helpful starting point: http://maarten.lippmann.us/?p=101
A site a friend of mine built uses a script to churn HTML pages into printable PDFs, too - http://philambdaupsilon.org. Not sure on the exact details of it, but he is an SO user, and I'll send this question to him, too.
Unfortunately, the best system on the market (at present) is passing the HTML & CSS to a ColdFusion server and have that return the rendered PDF. So if money isn't a big concern, this is the quickest to deploy solution that'll render the best results.
I've tried very hard to get FPDF, TCPDF, the R&OS pdf class, and even CodeIgniter's recommendation to work, but nothing with stable output for anything beyond the most basic/bland HTML files.
Honestly, if the ColdFusion solution isn't viable, I'd use html2ps, and then ps2pdf to convert your files into a PDF.
(This is all assuming that you don't want to take the time and design each PDF using the native PDF-creator code in PHP. This is what systems like SugarCRM use. Though its very functional with stable results, the actual creation of each PDF-generator file is a most painful process)
We have used Jasper Reports before. It's not what you'd call user-friendly, but it will talk directly to your database.
html2pdf works very well. You can use this to generate both HTML and PDF reports from the same source.
I'm fiddling with Black Sheep Invoices right now, which is great at first but now I'm having trouble actually getting it to render the PDFs. Lots of installation difficulties--probably a lot easier on your own server but i'm up on a shared host with it. The HTML output and data management portions are well done though, which is something you won't get out of just creating a postscript template. I was hoping to find a reference to a library that has an active development team though (Black Sheep is not being updated at this time).
If you want browser perfect HTML converted to PDF then try commandlineprint
You'll need to install firefox on a linux distro, disable all firefox alerts and then run it through a virtual display. Check this thread for more details.
It's infuriating to get running well but does give you the best results for HTML to PDF conversion I've seen.
OK, a search of Google Code projects turned up Simple Invoices, which is awesome and well maintained.
I use TROFF for my invoices because of its extremely simple textual encoding. The logic is a few lines of Perl. Keeping it simple.
For a Ruby solution, try Prawn: http://prawn.majesticseacreature.com/
I use open office on the server and then generate the XML for the document (just unzip the document and hack away)
Some can use Dhek template editor to define area/placeholder for existing PDF, without altering existing document, and then populate it to generate final doc (e.g. with user values from a form): https://github.com/applicius/dhek .

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