Pursuing the question of, whether a Linux subsystem, that runs under Android, due to the UserLAnd app, can be used for Web development.

It was a subject which I wrote about several months, or years ago, that I had installed the “UserLAnd” app on my Google Pixel C Tablet, so that I could install Debian Linux on it. And a question which one reader had asked me was, whether such an arrangement could be used, to carry out Web development. In fact, some question existed, as to whether proprietary software could be made to run, and my answer was, that it would be preferred to run only Free, Open-Source Software.

In the meantime, I’ve uninstalled Linux from the Pixel C, and installed it on my Samsung Galaxy Tab S6, which has 256GB of internal storage, so that this question can be examined more seriously.

The answer I’d give to this question is, that Web-development can be done in this way, as long as the developer accepts some severe restrictions.

  • Successful development of any kind will depend on whether the user has a real keyboard to type on.
  • The Open-Source application “Bluefish” runs out-of-the box, which is more than I can say for any sort of Python IDE.
  • Because there is little possibility to run a Web-server on the tablet, the features which Bluefish would normally have, to edit PHP Scripts as well, will simply need to be ignored. The ability to preview the Web-pages written, depends on the Guest System’s Firefox browser following the ‘prooted’ Guest System’s Filename-Paths, so that, when Bluefish opens Firefox, the HTML File will essentially be opened as if from the hard drive. And the feature works…

 

Screenshot_20200924-052525_VNC Viewer

Screenshot_20200924-052618_VNC Viewer

 

The main reason I would say, not to invest in paid-for software on this platform, is, because its full potential will not be realized.

The HTML and CSS Files created in this way will next need to be transferred to an actual Web-server, and some of the ways in which Bluefish would be set up on a real Linux box, would make this easier.

 

(Updated 10/03/2020, 4h00: )

Continue reading Pursuing the question of, whether a Linux subsystem, that runs under Android, due to the UserLAnd app, can be used for Web development.

Some perceivable inconsistencies, about whether the embedded worksheets can be viewed.

One of the facts which I did mention in an earlier posting, concern worksheets which I sometimes embedded into my postings as ‘<iframe>s’. In reality, there could be two reasons, why such worksheets fail to display in any one person’s browser:

  1. I could have embedded them, specifying (insecure) URLs that begin with ‘http://’, even though the reader may be visiting my blog, using a (secure) URL that begins with ‘httpS://’. Or,
  2. The posting might suggest that the reader “may need to” enable JavaScript from the domain ‘mathjax.org’, but, in certain cases this is not needed, while in other cases, it is.

‘Problem 1′ above is harder for the reader to fix at their end. It can be solved by fetching my posting using the insecure ‘http://’ URL, or, as I’ve done in a very recent posting, I could decide to embed the ‘<iframe>’ using a URL, which does not specify my domain-name, and just assumes that it’s to be the same, as the domain-name of my site.

‘Problem 2′ above represents a contradiction which may confuse some readers. Sometimes, when I generated an HTML version of a worksheet, I did this by simply clicking on a button, in the GUI of my software. In such cases, the HTML will require that the JavaScript be enabled. But, in certain other cases, all I really did was, to output the worksheet as a LaTeX document, and then to run a custom script on it, to generate other types of documents, one of which would have been an HTML document.

If I ran my custom script on some generic LaTeX document, that generates ‘HTML with equations’, it will do so in the form of ‘a hybrid document’. The resulting document is hybrid, because it can then be viewed in one of two ways:

  1. Using the built-in support for ‘MathML’, that some readers’ browsers have. This is less likely, because I only know of one browser that actually support it: ‘Firefox’. If the reader is using ‘MS Edge’ or the ‘Chrome’ browser to view my posting, I know that they do not support MathML as a built-in feature. But,
  2. Such a hybrid HTML document can also be viewed, by enabling the JavaScript that gets referred to as ‘MathJax’, and which essentially allows other browsers, including ‘MS Edge’ and ‘Chrome’, to view the equations.

I try to accommodate as many possible configurations of the readers’ browsers as I can, but the unfortunate reality is, that merely pressing the GUI button within my application, may generate HTML which is highlighted more nicely, but which is not a hybrid HTML document.

Dirk

 

Revisiting HTML, this time, With CSS.

When I first taught myself HTML, it was in the 1990s, and not only has the technology advanced, but the philosophy behind Web-design has also changed. The original philosophy was, that the Web-page should only contain the information, and that each Web-browser should define in what style that information should be displayed. But of course, when Cascading Style-Sheets were invented – which in today’s laconic vocabulary are just referred to as “Styles” – they represented a full reversal of that philosophy, since by nature, they control the very appearance of the page, from the server.

My own knowledge of HTML has been somewhat limited. I’ve bought cuspy books about ‘CSS’ as well as about ‘JQuery’, but have never made the effort to read each book from beginning to end. I mainly focused on what some key concepts are, in HTML5 and CSS.

Well recently I’ve become interested in HTML5 and CSS again, and have found, that to buy the Basic license of a WYSIWYG-editor named “BlueGriffon“, proved informative. I do have access to some open-source HTML editors, but find that even if they come as a WYSIWIG-editor, they mainly tend to produce static pages, very similar to what Web-masters were already creating in the 1990s. In the open-source domain, maybe a better example would be “SeaMonkey“. Beyond that, ‘KompoZer‘ can no longer be made to run on up-to-date 64-bit systems, and while “BlueFish”, a pronouncedly KDE-centric solution available from the package-manager, does offer advanced capabilities, it only does so in the form of an IDE.

(Updated 03/09/2018, 17h10 : )

Continue reading Revisiting HTML, this time, With CSS.

Instant Article versus AMP Showdown Looms.

There seems to be a development on the horizon, which has not hit the front pages yet, but which I think will become a major topic in the near future.

Facebook has announced that it is releasing a “WordPress” plugin, which will allow the creation of “Instant Article” articles, basically on a WYSIWYG basis. This could potentially become big. It should not be forgotten, that Google has a competing software product named “Accelerated Mobile Pages”, or ‘AMP’. This recent news about the WP-plugin, made me aware for the first time that both products exist.

Apparently, the way Facebook Instant Article works, is that the XML which usually makes up an RSS feed, has extended functionality. It would still get fetched from the server via HTTP 2.0 , but should give a better user experience to the owners of smart-phones, who have found for a long time that regular Web-browsing is still awkward from any type of phone. Granted, there do exist Web-browsers that are meant to optimize the layout of text dynamically, as well as versions of many sites that are optimized for phones, but apparently, this all still leaves users wanting.

And so Instant Article XML cannot really be said to be an enhanced type of XML, because the nature of XML is already stated in the acronym: ‘Extensible markup language’. In general, XML may contain definitions of custom tags, followed by actual content that uses these tags. This exists alongside a certain usage of XML, in which the tags are merely defined by a specific application, which uses a similar format to store data.

But Instant Article intends to be XML which contains tags, which some other XML would not contain. And while any advanced browser capable of subscribing to an RSS feed might also be able to view Instant Articles, the main advantage of this format is supposed to be, that it will adapt itself to easier viewing on smart-phones specifically. AFAIK, Facebook is also going to rely on its iPhone and Android apps, to display the Instant Articles in ways that require platform-specific implementation of the XML. Specifically, if the navigation of content is supposed to be possible ‘by tilting the phone’, then this goes beyond what XML tags can do, that are defined entirely in XML.

The Google product ‘AMP’ is supposedly not based on XML, nor on RSS feeds, but rather on HTML, which has added tags, which the browser can interpret due to a JavaScript library. This could be seen as homologous to how ‘JQuery’ can be understood by most browsers, because they are also able to download JavaScript libraries and work with those. But AMP is also designed to adapt itself to the type of browser dynamically, as well as to the size of each display, and give a better user experience than plain-old HTML does.

One aspect which both these products seem to sport, is the intention of providing greater content by way of images and video, and less by way of text. And this is one reason for which private hosting may not play any great role in this area in the near future. For the reader to be fetching this blog from my server, for instance, the browser is only needed to fetch a few kilobytes of data. With images that can turn into megabytes, and with HQ video that can turn into gigabytes.

I would not pretend to have the bandwidth needed, to stream video directly to the readers of my blog. And so there may also be little point, for me to look into ‘Instant Article’ or ‘AMP’ authoring for now.

And yet, the dominance of one of these platforms, or both, is likely to be determined on the basis of authoring, as well as on the basis of hosting / streaming. AFAIK, ‘AMP’ still needs to be coded in a somewhat difficult way, by the content authors. The fact that Facebook is releasing a WordPress plugin means, that affiliated publishers will also be able to create content more fluidly than before. And, the hosting service WordPress.com is likely ‘to have dibs’, before the open source version is released next month, even if WordPress.org users would like to get in on the game.

And so it would seem that the pressure is on Google for the moment. But I’m sure that Google will do what the competition does, which will be to offer something in response.

With Instant Article, the source is to be streamed by way of Facebook itself. With ‘AMP’, Google has already made its Cloud Platform available, to act as an additional component to the system, acting as the ‘AMP-Cache’, by which perhaps a less-restricted set of authors will be able to make content available.

And either way, I think that the usage scenario will be, that more in the spirit of how television used to work, viewers will be able to select their content, by tuning in to a specific feed they’re interested in, maybe to get up-to-date information.

For the past 20 years or so of the WWW,  HTML has dominated the scene. I see this development as a potentially valid form of progress, especially since it does not seem to be providing a monopoly to the providers. I welcome ‘AMP’ and ‘Instant Article’ content to my phone.

As far as my personal blog is concerned, while I cannot stream, I also have a solution. I can upload a video I would like people to see to YouTube, and can drag-and-drop the YouTube links into my blogs. Here, they would form URLs that seem to play as if embedded into my blog entry, while truly being streamed from the Google / YouTube server. For my purposes this should be good enough, since I also do not produce a lot of video footage, which would truly fascinate my blog readers.

And yet in comparison, I also appreciate the fact that there is no regulatory system in place, which would tell me that I cannot use HTML and PHP in this way. And therefore, I also appreciate that the extended usage of XML and JS-libraries, seems to be opening up new possibilities.

Only, I don’t think that many viewers are aware of this yet, since in many cases ‘Instant Article’ and ‘AMP’ are already providing content, in ways that do not need to announce their presence, while working on our phones.

Dirk