Is it possible to create a single html page containing embedded D3js charts, CommonMark text, and equations (e.g. Katex or MathJax) and have it all rendered the browser offline?
Must have:
Works offline using modern Firefox/Chrome/Safari, after having
downloaded a minimal number of JavaScript libs.
No requirement for installing anything beyond the web browser. So no local http server, Pandoc, R, Python etc.
Should have:
Possible to write everything in a single html file, which opens in a normal modern browser.
Good archival properties with minimal maintanence.
Motivation:
We work in a high security locked down IT environment and can’t install stuff, but we do have decent web browsers and can run javascript in them.
We routinely share small analytical reports internally, and are experimenting with delivering a directory containing
an html file (with embedded JSON data), and
downloaded D3 and Underscore librariess
All the internal customer has to do is click on index.html. So far this has been very succesful, but we'd like to use markdown and equations too.
We are vaguely aware of data science workbook solutions like Jupyter and Observable, but not sure that these meet our criteria.
Clarification
I know we can download libs and place them in a dir alongside index.html, but I'm not sure if a JavaScript library exists which can render the markdown and equations and write the results directly into the DOM. And even if such a library exists, where in index.html would the markdown be written? Is there some kind of html tag which can just hide a load of raw text which will be parsed by JS?
To answer your question, it is possible. You'll either need Node app that will render static HTML pages or simple HTML page with embedded Javascript. Since all these libraries are available as UDM packages, I suggest 2nd option.
CommonMark CDN: https://cdnjs.com/libraries/commonmark
KaTeX CDN: https://khan.github.io/KaTeX/docs/browser.html
You'll only need to download these libraries and include them in page. KaTeX includes JS to convert simple text to rendered mathematical equation, you only need to give it text and element where to render equation: https://khan.github.io/KaTeX/docs/api.html. CommonMark is similar but it only gives you rendered HTML, you need to insert it with element.innerHTML yourself: https://www.npmjs.com/package/commonmark.
Related
I have two HTML files: One acts as a template, supplying the navigation, sidebars, etc., and the other has the main content. I'm trying to figure out how best to insert the content into the template. I need persistent URLs, so my plan was to have the content page essentially replace itself with the template, plugging the text back into the resulting page. I'm really new to front-end programming and I'm suspicious that this may be an anti-pattern, so my first question is about whether I'm barking up the right tree. The problem seems universal, and I'm sure there must be a best practice, though I haven't yet seen it discussed. If this is an acceptable way to proceed, then what JavaScript function would allow me to access the HTML of two different pages at the same time?
[EDIT: It's a small page on GitHub]
Do not do this. At current implementation HTML is not designed to be template engine. You can use HTML import but it has not full support in browsers. (compatibility table).
Usually this problem can be solved with:
Use frontend framework. Libraries like angular.js or polymer.js (and so on) usually has support of importing HTML documents in different forms.
Build your application HTML. Task runners like grunt.js usually has plugin that includes HTML.
Use server side technologies to extend your HTML from base layouts
If your application have to be consisted from different HTMLs I recommend you to try polymer. It is polyfill for web components and designed to work in such way by default.
UPD:
About edit to your question. It seems like you just need template engine for HTML. You can google for it. I use nunjucks - javascript port of python's template engine jinja2. It is lightweight, simple and can be compiled right in browser.
Another way is to use special tools for building static web pages. You have mentioned that your page is blog build from simple HTML pages. Try to use pelican. It is the static websites (blogs) generator. It is simple and fast. You can build your HTML even on your local machine and just push your HTML pages to github.
I have a help system that is completely offline, no server, using file://.
I have one main page, with hundreds of line of html that represent many sections of the help system. I would like to stick each section in a html file and just include it. Unfortunately it seems like this is only possible with some nifty server side include techniques, with HTML5 (which I do not want to assume my users have), or with a nasty javascript hack where you copy your html file into js files with document.write calls for every line as written about here: Ways to include html in html.
What about something like handlebars.js or mustache.js? Can I use templating?
Since you don't want to use server-side includes, I would suggest using a static site generator (SSG).
If you are not familiar with SSG's, they allow you generate HTML pages from templates & includes (often Handlebars templates) and HTML, Markdown, JSON, or YAML, content using a CLI.
If you want to get started with an SSG, there are plenty of options, from Ruby based Jekyll, or Node.js based Assemble. In my opinion, Assemble is the best option and I would highly recommend it.
I have Javascript, Django templates, Python code, and CSS which all work with the same configuration data. Where's the best place to configure it?
Specifically, I have a browser-side entry widget in Javascript which controls an embedded Java app. When the user is done, the Javascript asks the Java applet for an image of the result, which will be embeded in the HTML. The user can specify if the image should be small, medium, or large. That image and the choice are sent via an AJAX call to my Django app, which does some input validation. When the HTML is displayed it includes my CSS, which has special a[href^=http://internal.server] markup to show those images in a different way than other images.
While someone asked a similar question, the answers were either: "use a DSL" or "use a format like XML or JSON." Neither of which work with CSS.
The two solutions I came up with are:
put the data in Python and have it generate the HTML through a Django form/template. Also have Django dynamically generate the Javascript configuration and generate that CSS.
I don't like this because I would rather serve all my Javascript and CSS statically.
Introduce a build step where configuration data gets applied to a template to build the respective Javascript, HTML, CSS, and Python files.
Which makes things more complicated because I'll have special "*.in" or such files which build the actual files, and everyone will have to watch out that they know which files are the ones to edit.
What do you do?
Use JSON. Generate the CSS dynamically, using caching to reduce load.
I think an really good approach would be to effectively have a DSL expressed indirectly via JSON data structures laid out using some sort of coding convention, coupled with a separate build step that used that to create the configuration files needed. If the tool(s) for this build step were written in Python, creating, maintaining, and enhancing it or them ought to be relatively easy.
Here's my problem: I want to build a website, mostly static but with some dynamic parts (a little blog for news, etc..).
My webserver can only do static files (it's actually a public dropbox directory!) but I don't want to repeat the layout in every html page!
Now, I see two possible solutions here: either I create an index.htm page that emulates site navigation with javascript and AJAX or I create all the different html pages and then somehow import the layout bits with javascript..
From you I need ideas and suggestions on how to implement this, which libraries to use, or maybe there exists even something tailored exactly for what I need?
Thanks!!
I would define the site layout in your index.html file, and then use JavaScript and Ajax to load the actual content into a content div on the page. That way your content files (fetched by Ajax) will be more or less plain HTML, with CSS classes defined in index.html. Also, I wouldn't recommend building a blog in pure HTML and JavaScript. It wouldn't be very interactive; no comments, ratings, etc. You could store your blog content in XML and then fetch and display it with Ajax and JavaScript, however.
While on the subject of XML, you could implement all your site content in XML. You should also store the list of pages (for generating navigation) as XML.
Just another one way. You can generate static HTML in your computer and upload result to dropbox. Look at emacs muse.
jQuery allows you to easily load a section of one page into another page. I recommend loading common navigation sections into the different pages, rather than the other way around to avoid back/forward problems. Layout can be done with a separate CSS file rather than with tables to minimize the amount of repeated code. For the blog, you could put each blog entry in a separate file and load each section individually.
However, I would just use something already available. TiddlyWiki, for example, is a self-contained wiki that is all in one file. It's very customizable, and there's already a blog plug-in available for it. You can work on the site on your hard drive or USB drive, and then you can upload it to the web when done. There's nothing more to it.
Have you considered using publishing software on your computer to combine your content with a template, resulting in a set of static pages that you can then upload to the dropbox?
Some options in this regard come to mind:
Movable Type - can output static HTML which can then be uploaded to the server
Adobe Dreamweaver
Apple iWork Pages
To handle comments, you can use Disqus. It inserts a complete comment system into your site using just JavaScript.
You can use the Google Closure templates. It's one of the fastest and most versatile javascript templating solutions around.
Do you localize your javascript to the page, or have a master "application.js" or similar?
If it's the latter, what is the best practice to make sure your .js isn't executing on the wrong pages?
EDIT: by javascript I mean custom javascript you write as a developer, not js libraries. I can't imagine anyone would copy/paste the jQuery source into their page but you never know.
Putting all your js in one file can help performance (only one request versus several). And if you're using a content distribution network like Akamai it improves your cache hit ratio. Also, always throw inline js at the very bottom of the page (just above the body tag) because that is executed synchronously and can delay your page from rendering.
And yes, if one of the js files you are using is also hosted at google, make sure to use that one.
Here's my "guidelines". Note that none of these are formal, they just seem like the right thing to do.
All shared JS code lives in the SITE/javascripts directory, but it's loaded in 'tiers'
For site-wide stuff (like jquery, or my site wide application.js), the site wide layout (this would be a master page in ASP.net) includes the file. The script tags go at the top of the page.
There's also 'region-wide' stuff (eg: js code which is only needed in the admin section of the site). These regions either have a common layout (which can then include the script tags) or will render a common partial, and that partial can include the script tags)
For less-shared stuff (say my library that's only needed in a few places) then I put a script tag in those HTML pages individually. The script tags go at the top of the page.
For stuff that's only relevant to the single page, I just write inline javascript. I try to keep it as close to it's "target" as possible. For example, if I have some onclick js for a button, the script tag will go below the button.
For inline JS that doesn't have a target (eg: onload events) it goes at the bottom of the page.
So, how does something get into a localised library, or a site-wide library?.
The first time you need it, write it inline
The next time you need it, pull the inline code up to a localised library
If you're referencing some code in a localized library from (approximately) 3 or more places, pull the code up to a region-wide library
If it's needed from more than one region, pull it up to a site-wide library.
A common complaint about a system such as this, is that you wind up with 10 or 20 small JS files, where 2 or 3 large JS files will perform better from a networking point of view.
However, both rails and ASP.NET have features which handle combining and caching multiple JS files into one or more 'super' js files for production situations.
I'd recommend using features like this rather than compromising the quality/readability of the actual source code.
Yahoo!'s Exceptional Performance Team has some great performance suggestions for JavaScript. Steve Souders used to be on that team (he's now at Google) and he's written some interesting tools that can help you decide where to put JavaScript.
I try to avoid putting javascript functions on the rendered page. In general, I have an application.js (or root.js) that has generic functionality like menu manipulation. If a given page has specific javascript functionality, I'll create a .js file to handle that code and mimic the dir structure on how to get to that file (also using the same name as the rendered file).
In other words, if the rendered page is in public/dir1/dir2/mypage.html, the js file would be in public/js/dir1/dir2/mypage.js. I've found this style works well for me, especially when doing templating on a site. I build the template engine to "autoload" my resources (css and js) by taking the request path and doing some checking for the css and js equivalents in the css and js directories on the root.
Personally, I try to include several Javascript files, sorted by module (like YUI does). But once in a while, when I'm writing essentially a one-liner, I'll put it on the page.
Best practice is probably to put it on Google's servers.
(Depends what you mean by "your" javascript though I suppose :)
This is something I've been wrestling with, too. I've ended up by using my back-end PHP script to intelligently build a list of required JS files based on the content requested by the user.
By organizing my JS files into a repository that contains multiple files organized by purpose (be they general use, focused for a single page, single section, etc) I can use the chain of events that builds the page on the back-end to selectively choose which JS files get included based on need (see example below).
This is after implementing my web app without giving this aspect of the code enough thought. Now, I should also add that the javascript I use enhances but does not form the foundation of my site. If you're using something like SproutCore or Ext I imagine the solution would be somewhat different.
Here's an example for a PHP-driven website:
If your site is divided into sections and one of those sections is calendar. The user navigates to "index.phhp?module=calendar&action=view". If the PHP code is class-based the routing algorithm instantiates the CalendarModule class which is based on 'Module' and has a virtual method 'getJavascript'. This will return those javascript classes that are required to perform the action 'view' on the 'calendar' module. It can also take into account any other special requirements and return js files for those as well. The rendering code can verify that there are no duplicates of js files when the javascript include list is built for the final page. So the getJavascript method returns an array like this
return array('prototype.js','mycalendar.js');
Note that this, or some form of this, is not a new idea. But it took me some time to think it important enough to go to the trouble.
If it's only a few hundred bytes or less, and doesn't need to be used anywhere else, I would probably inline it. The network overhead for another http request will likely outweigh any performance gains that you get by pulling it out of the page.
If it needs to be used in a few places, I would put the function(s) into a common external file, and call it from an inline script as needed.
If you are targeting an iphone, try to keep anything that you want cached under 25k.
No hard and fast rules really, every approach has pros and cons, would strongly recommend you check out the articles that can be found on yahoo's developer section, so you can make informed decisions on a case by case basis.