Category Archives: software development

Gartner on Mobile App Development Platforms: Kony, Mendix, Microsoft, Oracle and Outsystems the winners

Gartner has published a paper and Magic Quadrant on Mobile App Development Platforms (MDAPs), which you can read for free thanks to Progress, pleased to be named as a “Visionary”, and probably from other sources.

According to Gartner, an MDAP has three key characteristics:

  • Cross-platform front-end development tools
  • Back-end services that can be used by diverse clients, not just the vendor’s proprietary tools.
  • Flexibility to support public and internal deployments

Five vendors ranked in the sought-after “Leaders” category. These are:

  • Kony, which offers Kony Visualizer for building clients, Kony Fabric for back-end services, and Kony Nitro Engine, a kind of cross-platform runtime based on Apache Cordova .
  • Mendix, which has visual development and modeling tools and multi-cloud, containerised deployment of back-end services
  • Microsoft, which has Xamarin cross-platform development, Azure cloud services, and PowerApps for low-code development
  • Oracle, which has Oracle Mobile Cloud Enterprise including JavaScript Extension Toolkit and deployment via Apache Cordova
  • Outsystems, a low-code platform which has the Silk UI Framework and a visual modeling language, and hybrid deployment via Apache Cordova

Of course there are plenty of other vendors covered in the report. Further, because this is about end-to-end platforms, some strong cross-platform development tools do not feature at all.

A few observations. One is the prominence of Apache Cordova in these platforms. Personally I have lost enthusiasm for Cordova, now that there are several other options (such as Xamarin or Flutter) for building native code apps, which I feel deliver a better user experience, other things being equal (which they never are).

With regard to Microsoft, Gartner notes the disconnect between PowerApps and Xamarin, different approaches to application development which have little in common other than that both can be used with Azure back-end services.

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Microsoft PowerApps

I found the report helpful for its insight into which MDAP vendors are successfully pitching their platform to enterprise customers. What it lacks is much sense of which platforms offer the best developer experience, or the best technical capability when it comes to solving those unexpected problems that inevitably crop up in the middle of your development effort and take a disproportionate amount of time and effort to solve.

RemObjects Elements: mix and match languages and platforms as you like

The world of software development has changed profoundly in the last decade or so. Once it was a matter of mainly desktop Windows development for the client, mainly Java for server-based applications with web or Windows clients. Then came mobile and cloud – the iPhone SDK was released in March 2008, kicking off a new wave of mobile applications, while Amazon EC2 (Elastic Compute Cloud) came out of beta in October 2008. Microsoft tussled within itself about what to do with Windows Mobile and ended up ceding the entire market to Android and iOS.

The consequence of these changes is that business developers who once happily developed Windows desktop applications have had to diversify, as their customers demand applications for mobile and web as well. The PC market has not gone away, so there has been growing interest in both cross-platform development and in how to port Windows code to other platforms.

Embarcadero took Delphi, a favourite development tool based on an Object Pascal compiler, down a cross-platform path but not to the satisfaction of all Delphi developers, some of whom looked for other ways to transition to the new world.

Founded in 2002, RemObjects had a project called Chrome, which compiled Delphi’s Object Pascal to .NET executables. This product was later rebranded Oxygene. For a while Embarcadero bundled a version of this with Delphi, calling it Prism, after abandoning its own .NET compilation tools.

The partnership with Embarcadero ended, but RemObjects pressed on, adding language features to its flavour of Object Pascal and adding support for Mac OS X, iPhone and Java.

In February 2015 the company was an early adopter of Apple’s Swift language, introducing a Swift compiler called Silver that targets Android, .NET and native Mac OS X executables.

The company now offers a remarkable set of products for developers who want to target new platforms but in a familiar language:

  • Oxygene: Object Pascal
  • Silver: Swift 3 (and most of Swift 4)
  • Hydrogene: C# 7
  • Iodine: Java 8

Each language can import APIs from the others, and compile to all the platforms – well, there are exceptions, but this is the general approach.

More precisely, RemObjects defines four target platforms:

  • Echoes: .NET and .NET Core including ASP.NET and Mono
  • Cooper: Java and Android
  • Toffee: Mac, iOS, tvOS
  • Island: CPU native and WebAssembly

So if you fancy writing a WPF (Windows Presentation Foundation) application in Java, you can:

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As you may spot from the above screenshot, the RemObjects tools use Visual Studio as the IDE. This is a limitation for Mac developers, so the company also developed a Mac IDE called Fire, and now a Windows IDE called Water (in preview) for those who dislike the Visual Studio dependency.

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Important to note: RemObjects does not address the problem of cross-platform user interfaces. In this respect it is similar to the approach taken by Xamarin before that company came up with the idea of Xamarin Forms. So this is about sharing non-visual code and libraries, not cross-platform GUI (Graphical User Interface). If you are targeting Cocoa, you can use Apple’s Interface Builder to design your user interface, for example.

Of course WebAssembly and HTML is an interesting option in this respect.

A notable absentee from the list of RemObjects targets is UWP (Universal Windows Platform), a shame given the importance Microsoft still attaches to this.

RemObjects is mainly focused  on languages and compilers rather than libraries and frameworks. The idea is that you use the existing libraries and frameworks that are native to the platform you are targeting. This is a smart approach for a small company that does not wish to reinvent the wheel.

That said, there is a separate product called Data Abstract which is a multi-tier database framework.

These are interesting products, but as a journalists I have struggled to give them much coverage, because of their specialist nature and also the demands on my time as someone who prefers to try things out rather than simply relay news from press releases. I also appreciate that the above information is sketchy and encourage you to check out the website if these tools pique your interest.

Embarcadero launches free Community Edition of Delphi and C++Builder for mainly non-commercial use

A new Community Edition of Delphi and C++Builder, visual development tools for Windows, Mac, Android and iOS, has been released by Embarcadero.

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The tools are licensed for non-commercial use or for commercial use (for up to 5 developers) where revenue is less than $5000 per year. It is not totally clear to me, but I believe this means the total revenue (or for non-profits, donations) of the individual or organisation, not just the revenue generated by Community Edition applications. From the EULA:

The Community Edition license applies solely if Licensee cumulative annual revenue (of the for-profit organization, the government entity or the individual developer) or any donations (of the non-profit organization) does not exceed USD $5,000.00 (or the equivalent in other currencies) (the “Threshold”). If Licensee is an individual developer, the revenue of all contract work performed by developer in one calendar year may not exceed the Threshold (whether or not the Community Edition is used for all projects).

Otherwise, the Community Editions are broadly similar to the Professional Editions of these tools. Note that even the Professional Edition lacks database drivers other than for local or embedded databases so this is a key differentiator in favour of the Architect or Enterprise editions.

An annoyance is that you cannot install both Delphi and C++ Builder Community Editions on the same PC. For this you need RAD Studio which has no Community Edition.

Delphi and C++ Builder are amazing tools for Windows desktop development, with a compiler that generates fast native code. For cross-platform there is more competition, not least from Microsoft’s Xamarin tools, but the ability to share code across multiple platforms has a powerful attraction.

Get Delphi Community Edition here and C++Builder Community Edition here.

Using the Xamarin WebView for programmatic display of HTML content

Xamarin Forms is a key framework for C# and .NET developers since it lets you target Android, iOS and to some extent Windows (UWP and therefore Windows 10 only) with maximum code reuse. I have a longstanding interest in embedded web browser controls and was glad to see that Xamarin Forms supports a capable WebView control. The WebView wraps Chrome on Android, Safari on iOS, and Edge on UWP.

I did a quick hands-on. In this example (running in the Android emulator on Hyper-V, of course), the HTML is generated programmatically and the CSS loaded from local storage. I also added some script to show the User Agent string that identifies the browser.

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There are a few things needed to make this work. Some XAML to put the WebView on a page. Then to load content into the WebView you need an HTMLWebViewSource object. If you are loading external files, you must set the BaseUrl property of this object as well as the HTML itself. The BaseUrl tells the control where to look for files that have a relative address. This varies according to the target platform, so you use the Xamarin Forms Dependency Service to set it correctly for each platform.

In Visual Studio, you place the files you want to load in the appropriate folder for each platform. For Android, this is the Assets folder.

That is about all there is to it. As you can see from the above screenshot, I wrote very little code.

The WebView control can also display PDF documents. Finally, there is an EvaluateJavaScriptAsync method that lets you call JavaScript in a WebView and read the results from C#.

This JavaScript bridge is a workaround for the most obvious missing feature, that you cannot directly read the HTML content from the WebView. If this is a full programmatic solution and you generate all the HTML yourself, you can add JavaScript to do what you want. If the user is allowed to navigate anywhere on the web, you cannot easily grab the HTML; but this could be a good thing, in case the user entered a password or is viewing confidential data. You can grab the destination URL from the Navigating event and read it separately if necessary. But the intent of the control is to let you create rich applications that take advantage of the browser’s ability to render content, not to invade a user’s privacy by tracking their web browsing.

Instant applications considered harmful?

Adrian Colyer, formerly of SpringSource, VMWare, and Pivotal, is running an excellent blog where he looks at recent technical papers. A few days ago he covered The Rise of the Citizen Developer – assessing the security impact of online app generators. This was about online app generators for Android, things like Andromo which let you create an app with a few clicks. Of course the scope of such apps is rather limited, but they have appeal as a quick way to get something into the Play Store that will promote your brand, broadcast your blog, convert your website into an app, or help customers find your office.

It turns out that there are a few problems with these app generators. Andromo is one of the better ones. Some of them just download a big generic application with a configuration file that customises it to your requirements. Often this configuration is loaded from the internet, in some cases over HTTP with no encryption. API keys used for interaction with other services such as Twitter and Google can easily leak. They do not conform to Android security best practices and request more permissions that are needed.

Low code or no-code applications are not confined to Android applications. Appian promises “enterprise-grade” apps via its platform.  Microsoft PowerApps claims to “solve business problems with intuitive visual tools that don’t require code.” It is an idea that will not go away: an easy to use visual environment that will enable any business person to build productive applications.

Some are better than others; but there are inherent problems with all these kinds of tools. Three big issues come to mind:

  1. Bloat. You only require a subset of what the application generator can do, but by trying to be universal there is a mass of code that comes along with it, which you do not require but someone else may. This inevitably impacts performance, and not in a good way.
  2. Brick walls. Everything is going well until you require some feature that the platform does not support. What now? Often the only solution is to trash it and start again with a more flexible tool.
  3. Black box. You app mostly works but for some reason in certain cases it gives the wrong result. Lack of visibility into what it happening behind the scenes makes problems like this hard to fix.

It is possible for an ideal tool to overcome these issues. Such a tool generates human-understandable code and lets you go beyond the limitations of the generator by exporting and editing the project in a full programming environment. Most of the tools I have seen do not allow this; and even if they do, it is still hard for the generator to avoid generating a ton of code that you do not really need.

The more I have seen of different kinds of custom applications, the more I appreciate projects with nicely commented textual code that you can trace through and understand.

The possibility of near-instant applications has huge appeal, but beware the hidden costs.

Inside Azure Cosmos DB: Microsoft’s preferred database manager for its own high-scale applications

At Microsoft’s Build event in May this year I interviewed Dharma Shukla, Technical Fellow for the Azure Data group, about Cosmos DB. I enjoyed the interview but have not made use of the material until now, so even though Build was some time back I wanted to share some of his remarks.

Cosmos DB is Microsoft’s cloud-hosted NoSQL database. It began life as DocumentDB, and was re-launched as Cosmos DB at Build 2017. There are several things I did not appreciate at the time. One was how much use Microsoft itself makes of Cosmos DB, including for Azure Active Directory, the identity provider behind Office 365. Another was how low Cosmos DB sits in the overall Azure cloud system. It is a foundational piece, as Shukla explains below.

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There were several Cosmos DB announcements at Build. What’s new?

“Multi-master is one of the capabilities that we announced yesterday. It allows developers to scale writes all around the world. Until yesterday Cosmos DB allowed you to scale writes in a single region but reads all around the world. Now we allow developers to scale reads and writes homogeneously all round the world. This is a huge deal for apps like IoT, connected cars, sensors, wearables. The amount of writes are far more than the amount of reads.

“The second thing is that now you get single-digit millisecond write latencies at the 99 percentile not just in one region.

“And the third piece is that what falls out of this high availability. The window of failover, the time it takes to failover from one region when a disaster happens, to the other, has shrunk significantly.

“It’s the only system I know of that has married the high consistency models that we have exposed with multi-master capability as well. It had to reach a certain level of maturity, testing it with first-party Microsoft applications at scale and then with a select set of external customers. That’s why it took us a long time.

“We also announced the ability to have your Cosmos Db database in your own VNet (virtual network). It’s a huge deal for enterprises where they want to make sure that no data leaks out of that VNet. To do it for a global distributed database is specially hard because you have to close all the transitive networking dependencies.”

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Technical Fellow Dharma Shukla

Does Cosmos DB work on Azure Stack?

“We are in the process of going to Azure Stack. Azure Stack is one of the top customer asks. A lot of customers want a hybrid Cosmos DB on Azure Stack as well as in Azure and then have Active – Active. One of the design considerations for multi master is for edge devices. Right now Azure has about 50 regions. Azure’s going to expand to let’s say 200 regions. So a customer’s single Cosmos DB table spanning all these regions is one level of scalability. But the architecture is such that if you directly attach lots of Azure Stack devices, or you have sensors and edge devices, they can also pretend to be replicas. They can also pretend to be an Azure region. So you can attach billions of endpoints to your table. Some of those endpoints could be Azure regions, some of them could be instances of Azure Stack, or IoT hub, or edge devices. This kind of scalability is core to the system.”

Have customers asked for any additional APIs into Cosmos DB?

“There is a list of APIs, HBase, richer SQL, there are a number of such API requests. The good news is that the system has been built in a way that adding new APIs is relatively easy addition. So depending on the demand we continue to add APIs.”

Can you tell me anything about how you’ve implemented Cosmos DB? I know you use Service Fabric. Do you use other Azure services?

“We have dedicated clusters of compute machines. Cosmos DB is a Ring 0 service. So it’s there any time Azure opens a new region, Cosmos DB clusters have provision by default. Just like compute, storage, Cosmos DB is also one of the Ring 0 services which is the bottommost. Azure Active Directory for example depends on Cosmos DB. So Cosmos DB cannot take a dependency on Active Directory.

“The dependency that we have is our own clusters and machines, on which we put Service Fabric. For deployment of Cosmos DB code itself, we use Service Fabric. For some of the load balancing aspects we use Service Fabric. The partition management, global distribution, replication, is our own. So Cosmos DB is layered on top of Service Fabric, it is a Service Fabric application. But then it takes over. Once the Cosmos DB bits are laid out on the machine then its replication and partition management and distribution pieces take over. So that is the layering.

“Other than that there is no dependency on Azure. And that is why one of the salient aspects of this is that you can take the system and host it easily in places like Azure Stack. The dependencies are very small.

“We don’t use Azure Storage because of that dependency. So we store the data locally and then replicate it. And all of that data is also encrypted at rest.”

So when you say it is not currently in Azure Stack, it’s there underneath, but you haven’t surfaced it?

“It is in a defunct mode. We have to do a lot of work to light it up. When we light up it on such on-prem or private cloud devices, we want to enable this active to active pathway. So you are replicating your data and that is getting synchronized with the cloud and Azure Stack is one of the sockets.”

Microsoft itself is using Cosmos DB. How far back does this go? Azure AD is quite old now. Was it always on Cosmos DB / DocumentDB?

“Over the years Office 365, Xbox, Skype, Bing, and more and more of Azure services, have started moving. Now it has almost become ubiquitous. Because it’s at the bottom of the stack, taking a dependency on it is very easy.

“Azure Active Directory consists of a set of microservices. So they progressively have moved to Cosmos DB. Same situation with Dynamics, and our slew of such applications. Skype is by and large on Cosmos DB now. There are still some fragments of the past.  Xbox and the Microsoft Store and others are running on it.”

Do you think your customers are good at making the right choices over which database technology to use? I do pick up some uncertainty about this.

“We are working on making sure that we provide that clarity. Postgres and MySQL and MariaDB and SQL Server, Azure SQL and elastic pools, managed instances, there is a whole slew of relational offerings. Then we have Cosmos DB and then lots of analytical offerings as well.

“If you are a relational app, and if you are using a relational database, and you are migrating from on-prem to Azure, then we recommend the relational family. It comes with this fundamental scale caveat which is that up to 4TB. Most of those customers are settled because they have designed the app around those sorts of scalability limitations.

“A subset of those customers, and a whole bunch of brand new customers, are willing to re-write the app. They know that that they want to come to cloud for scale. So then we pitch Cosmos DB.

“Then there are customers who want to do massive scale offline analytical processing. So there is, Databricks, Spark, HD Insight, and that set of services.

“We realise there are grey lines between these offerings. We’re tightening up the guidance, it’s valid feedback.”

Any numbers to flesh out the idea that this is a fast-growing service for Microsoft?

“I can tell you that the number of new clusters we provision every week is far more than the total number of clusters we had in the first month. The growth is staggering.”

Is Ron Jeffries right about the shortcomings of Agile?

A post from InfoQ alerted me to this post by Agile Manifesto signatory Ron Jeffries with the rather extreme title “Developers should abandon Agile”.

If you read the post, you discover that what Jeffries really objects to is the assimilation of Agile methodology into the old order of enterprise software development, complete with expensive consultancy, expensive software that claims to manage Agile for you, and the usual top-down management.

All this goes to show that it is possible do do Agile badly; or more precisely, to adopt something that you call Agile but in reality is not. Jeffries concludes:

Other than perhaps a self-chosen orientation to the ideas of Extreme Programming — as an idea space rather than a method — I really am coming to think that software developers of all stripes should have no adherence to any “Agile” method of any kind. As those methods manifest on the ground, they are far too commonly the enemy of good software development rather than its friend.

However, the values and principles of the Manifesto for Agile Software Development still offer the best way I know to build software, and based on my long and varied experience, I’d follow those values and principles no matter what method the larger organization used.

I enjoyed a discussion on the subject of Agile with some of the editors and writes at InfoQ during the last London QCon event. Why is it, I asked, that Agile is no longer at the forefront of QCon, when a few years back it was at the heart of these events?

The answer, broadly, was that the key concepts behind Agile are now taken for granted so that there are more interesting things to discuss.

While this makes sense, it is also true (as Jeffries observes) that large organizations will tend to absorb these ideas in name only, and continue with dark methods if that is in their culture.

The core ideas in Extreme Programming are (it seems to be) sound. Working in small chunks, forming a team that includes the customer, releasing frequently and delivering tangible benefits, automated tests and continuous refactoring, planning future releases as you go rather than in one all-encompassing plan at the beginning of a project; these are fantastic principles and revolutionary when you first come across them. See here for Jeffries’ account of what is Extreme Programming.

These ideas have everything to do with how the team works and little to do with specific tools (though it is obvious that things like a test framework, DevOps strategy and so on are needed).

Equally, you can have all the best tools but if the team is not functioning as envisaged, the methodology will fail. This is why software development methodology and the psychology of human relationships are intimately linked.

Real change is hard, and it is easy to slip back into bad practices, which is why we need to rediscover Agile, or something like it, repeatedly. Maybe the Agile word itself is not so helpful now; but the ideas are as strong as ever.

What is happening with desktop development on Windows and will WPF be upgraded at last?

Once upon a time all Windows development was desktop development. Then there was web development, but that was a server thing. Then in October 2012 Windows 8 arrived, and it was all about full-screen, touch control and Store-delivered applications that were sandboxed and safe to run. Underneath this there was a new platform-within-a-platform called the Windows Runtime or WinRT (or sometimes Metro). Developing for Windows became a choice: new WinRT platform, or old-style desktop development, the latter remaining necessary if your application needed more features than were available in WinRT, or to run on Windows 7.

Windows 8 failed and was replaced by Windows 10 (July 2015), in large part a return to the desktop. The Start menu returned, and each application again had a window. WinRT lived on though, now rebranded as UWP (Universal Windows Platform). The big selling point was that your UWP app would run on phones, Xbox and HoloLens as well as PCs. It was still locked down, though less so, and still Store-delivered.

Then Microsoft decided to abandon Windows Phone, a decision obvious to Microsoft-watchers in June 2015 when ex-Nokia CEO Stephen Elop left Microsoft, just before the launch of Windows 10, even though Windows Phone was not formally killed off until much later. UWP now had a rather small u (that is, not very universal).

In addition, Microsoft decided that locking down UWP was not the way forward, and opened up more and more Windows APIs to the platform. The distinction between UWP and desktop applications was further blurred by Project Centennial, now known as Desktop Bridge, which lets you wrap desktop applications for Store delivery.

Perhaps the whole WinRT/UWP thing was not such a good idea. A side-effect though of all the focus on UWP was that the old development frameworks, such as Windows Forms (WinForms) and Windows Presentation Foundation (WPF), received little attention – even though they were more widely used. Some Windows 10 APIs were only available in UWP, while other features only worked in WinForms or WPF, giving developers a difficult decision.

The Build 2018 event, which was on last week in Seattle, was the moment Microsoft announced that it would endeavour to undo the damage by bringing UWP and desktop development together. “We’ve taken all the UI stacks and merged them together” said Mike Harsh and Scott Hunter in a session on “Modernizing desktop apps” (BRK3501 if you want to look it up).

According to Harsh and Hunter, Windows desktop application development is increasing, despite the decline of the PC (note that this is hardly a neutral source).

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So what was actually announced? Here is a quick summary. Note that the announced features are for the most part applicable to future versions of Windows 10. As ever, Build is for the initial announcement. So features are subject to change and will not work yet, other than possibly in pre-release form.

Greater information density in UWP applications. WinRT/UWP was originally designed for touch control, so with lots of white space. Most Windows users though have mouse and keyboard. The spacious UWP layout looked wrong on big desktop displays, and it made porting applications harder. The standard layout is getting less dense, and a new Compact Size, an application setting, will pack more information into the same space.

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More controls for UWP. New DataGrid, Forms with data validation, Menu bar, and coming in future, Status bar, tab controls and Ribbon. The idea is to make UWP more suitable for line-of-business applications, which accounts for a large part of Windows application development overall.

New Windowing APIs for UWP. WinRT/UWP was designed for full-screen applications, not the popup-dialogs or floating windows possible in desktop applications. Those capabilities are coming though. We will get tool windows, light-dismiss windows (eg type and press Enter), and multiple windows on one thread so that they work like a single application when minimized or cycled through with alt-tab. Coming in future are topmost windows, modal windows, custom title bars, and maybe even MDI (Multiple Document Interface), though this last seems surprising since it is discouraged even in the desktop frameworks.

What many developers will care about more though is new features coming to desktop applications. There are two big announcements.

.NET Core 3.0 will support WinForms and WPF. This is big news, partly because it performs better than the Windows-only .NET Framework, but more important, because it allows side-by-side deployment of the .NET runtime. Even better, a linker will let you deliver a .NET Core desktop application as a single executable with no dependencies. What performance gain? An example shown at Build was an application which uses File APIs running nearly three times faster on .NET Core 3.0.

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XAML Islands enabling UWP features in WinForms and WPF. The idea is that you can pop a UWP host control in your WinForms or WPF application, and show UWP content there. Microsoft is also preparing wrapper controls that you can use directly. Mentioned were WebView, MediaPlayer, InkCanvas, InkToolBar, Map and SwapChainPanel (for DirectX content). There will be a few compromises. The XAML host window will be rectangular (based on an HWND) which means non-rectangular and transparent content will not work correctly. There is also the Windows 7 problem: no UWP on Windows 7, so what happens to your XAML Islands? They will not run, though Microsoft is working on a mechanism that lets your application substitute compatible Windows 7 content rather than crashing.

MSIX deployment. MSIX is Microsoft’s latest deployment technology. It will work with both UWP and Desktop applications, will support Windows 7 and 10, will provide for auto-updates, and will have tooling built into Visual Studio, as well as a packager for both your own and third-party applications. Applications installed with MSIX are managed and updated by Windows, have tamper protection, and are installed per-user. It seems to build upon the Desktop Bridge concept, the aim being to make Windows more manageable in the Enterprise as well as safer for all users, if Microsoft can get widespread adoption. The packaging format will also work on Android, Mac and Linux and you can check out the SDK here.

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Will WPF or WinForms be updated?

The above does not quite answer the question, will WPF or Windows Forms be significantly updated, other than with the ability to use UWP content? I could not get a clear answer on this question at Build, though I was told that adding support for .NET Core 3.0 required significant changes to these frameworks so it is no longer true to say they are frozen. With regard to WPF Microsoft Corporate VP Julia Liuson told me:

“We will be looking at more controls, more capabilities. It is widely recognised that WPF is the best framework for desktop development on Windows. The fact that we’re moving on top of .NET Core 3.0 gives us a path forward.”

That said, I also heard that the team would rather write code once and use it across UWP, WPF and WinForms via XAML Islands, than write new controls for each framework. That makes sense, the difficulty being Windows 7. Microsoft would rather promote migration to Windows 10, than write new UI components that work across both Windows 7 and Windows 10.

A week of QCon: introduction

I attended QCon London last week and found it fascinating, but have not written as much about it as I intended because of various other deadlines. In order to address this I will do a quick daily post for the next week or so.

QCon is a software development conference run by InfoQ. It is vendor-neutral and focuses on large-scale enterprise development as well as future trends, language choices and changes, software architecture and more. If you delve into the history of the event it has championed techniques including Agile development, Service Oriented Architecture, Microservices, and now AI. The event has a culture and an ethos, which is something to do with human-centred software, team communications, taking hte side of the user, aversion to unnecessary complexity, and constant exploration of emerging technology.

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Laura Bell of SafeStack speaks at QCon London on Architecting a Culture of Secure Software.

QCon, like many other events, encourages attendees to give feedback on sessions they attend. At other events I have often seen forms with several categories and questions like “How well did the speaker know their subject” and “What was your biggest takeaway from this session”? While such questions are reasonable, the problem is that they are too difficult and time-consuming and therefore not many respond, or the responses are of low quality. The QCon organisers decided years ago that the only feedback system that works is to have attendees vote good, indifferent or poor as they leave. This used to be done with coloured paper and is now electronic. I mention this because it says something about the event culture: let’s prefer something that works and is not a burden, despite the seeming crudity of a 1-2-3 scoring system. And of course even such basic information is highly valuable in discerning which sessions were most appreciated.

The event prefers practitioners, engineers and team leads over evangelists, trainers and consultants. It attracts a particularly able audience:

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Of course you can learn plenty outside the actual sessions by chatting to other attendees.

Up next: technical ethics at QCon London.

Setting up PHP for development on Windows Subsystem for Linux in Windows 10

I have been working a little with PHP, for the first time for a while, and soon found it annoying not to have the convenience of instant application testing and line by line debugging. I have set up a PHP development environment before using XAMPP for Windows and Eclipse, but it was fiddly. I also prefer PHP on Linux, which is where my scripts will be running.

Since Windows 10 now has a Linux environment built-in, called Windows Subsystem for Linux (WSL), I decided to set this up to run Apache, PHP and MySQL and to try debugging my scripts there.

My PC is a recent installation and I had not yet installed WSL. To do so, you have to both download a Linux distribution from the Store (I chose Ubuntu), and enable WSL in Windows features. Then restart, launch Ubuntu, set a username and password, and you are up and running.

Note the Linux commands that follow should be run as root using sudo.

Before doing anything else, I got Ubuntu up to date:

apt-get update

apt-get upgrade

Then I installed the LAMP suite:

apt-get install lamp-server^

(the final ^ is intentional; see the guide here).

To check that everything is working, I created the file phpinfo.php in /var/www/html with the following contents:

<?php phpinfo(); ?>

and restarted Apache:

/etc/init.d/apache2 restart

Note: if you have IIS running in Windows, or another web server, Apache will not be able to listen on port 80. Change the port in /etc/apache2/ports.conf and in /etc/apache2/sites-enabled/000-default.conf

Then I opened a web browser on the Windows side and browsed to localhost:

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and

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We are up and running, but not debugging PHP yet. Remember the basic rules of WSL:

  • you cannot change Linux files from Windows.
  • you can access Windows files from Linux.

We want to edit PHP from Windows, so we’ll define a site that uses Windows files. Windows files are under /mnt/c (or whatever drive letter you are using).

So if you example you have your PHP website in a folder called c:\websites\mysite, you can have Apache serve files from that folder.

The quickest way to get up and running is to create a symbolic link in the Apache home directory, in my case /var/www/html. Change to that directory and type:

ln -s /mnt/c/websites/mysite mysite

Now you can view the site at http://localhost/mysite/

This worked first time for me, complete with PHP running. You could also set up multiple virtual hosts in Apache, and use the hosts file in Windows to map other host names to localhost.

Next, you probably want PHP to show error messages. To do this, replace the default php.ini with the development version (or tweak it according to your own preferences. At the time of writing, on Ubuntu, the default PHP version is 7.0 and php.ini-development is located in /usr/lib/php/7.0/php.ini-development. So I backed up the ini file at /etc/php/7.0/apache2, replaced it with the development version, and restarted Apache. My PHP form immediately showed me a non-fatal undefined index error, so it worked.

There is one small inconvenience. Apache in WSL will only run during the session. So before starting work, you have to open Ubuntu and type:

sudo apache2ctl start

Well, background task support is coming to WSL but I do not regard this as a big problem.

OK, this is cool, we can make changes in the PHP code in our favourite Windows editor, save, and view the results directly in the browser. But what about line-by-line debugging? For this, we are going to use Visual Studio Code with the PHP Debug extension:

image

Then on the Ubuntu side:

apt-get install php-xdebug

Restart Apache:

apache2ctl restart

Check that phpinfo.php now shows an Xdebug section. Then edit php.ini and add the following:

[XDebug]
xdebug.remote_enable = 1
xdebug.remote_autostart = 1

Restart Apache again and XDebug is ready to go.

Over in Visual Studio code there is a little more work to do. The problem is that although everything is running on localhost, the location of the files looks different to Linux than to Windows. We can fix this with a pathMappings setting. In Visual Studio code, open the PHP file you want to debug. Click the Debug icon and then the little gearwheel near top left; this will open launch.json. By default there are a couple of settings for XDebug. These are OK for a default setup, but we need to add path mapping so that the debugger knows where to find the files. For example:

image

Now you can set a breakpoint, start debugging, and open the page in your browser:

image

More guidance on the PHP Debug extension by Felix Becker is here.

Final thoughts

This is cool; but is it better or worse than an old-style VM running Linux and PHP? The WSL solution is lightweight and convenient, but unlike a VM it is not isolated and you may hit issues that are unique to WSL, because not everything runs. I did happen to suffer crashes in Visual Studio and in Outlook while WSL was running; it may well be coincidence, but I cannot help wondering if WSL might be to blame.

Still, a great feature of WSL is that when you exit your session, it goes away, so it is not too intrusive. I plan to use it for PHP debugging and will see how it goes.