Wednesday, 27 May 2009

News Flash: Microsoft Reinvents Eiffel, 18 Years On

One of the major influences on the middle third of my career thus far was Bertrand Meyer's Eiffel programming language and its concept of design by contract. With such tools, for the first time (at least as far as I was aware), entire classes of software defects could be reliably detected at run time (dynamic checking) and/or at compile time (static checking). I worked on a couple of significant project teams in the mid- to late '90s that used Eiffel quite successfully. Further, it impacted my working style in other languages; for several years, I had a reputation on C and C++ projects for putting far more assert statements than was considered usual by my colleagues. More importantly, it made me start thinking in a different way about how to create working code. Later, as I became aware of automated testing, continuous integration and what is now called agile development, they were all logical extensions of the principles I had already adopted.

This all happened over a period of 15 or so years, in a field where anyone with more than 2 or 3 years' experience is considered "senior". But for me, and most other serious practitioners who I knew and worked with, two to three years was really just about as long as it took to answer more questions than we raised. That, in most crafts, is considered one of the signs of becoming a journeyman rather than a wet-behind-the-ears apprentice.

Then, a few hours ago, I was reading a blog entry by one David R. Heffelfinger which mentioned a project at Microsoft DevLabs called "SmallBasic". Another project that the same organization developed is called "Code Contracts"; there's a nice little set of tools (which will be built into the upcoming Visual Studio 2010 product), and a nice introductory video. Watch the video (you'll need Silverlight to view it), and then do some research on Eiffel and design-by-contract and so on, and it's very difficult not to see the similarities.

So, on the one hand, I'm glad that .NET developers will finally be getting support for 20-year-old concepts (by the time significant numbers of developers use VS 2010 and .NET 4.0). Anything that helps improve the developer and user experiences on Windows (or, in fact, any platform) is by definition a Good Thing™.

On the other hand, I see more evidence of Microsoft's historical Not Invented Here mentality; beating the drum for "new and wonderful ideas for Windows development" that developers on other platforms have been using effectively for some time. While the Code Contracts project indirectly credits Eiffel — the FAQ page links to Spec# at Microsoft Research, which lists Eiffel as one of its influences — it would have been nice to see acknowledgement and explanation of precursor techniques be made more explicitly. Failure to do so merely reinforces the wisdom of Santayana as applied to software: "Those who cannot remember the past are condemned to repeat it", as well as "Fanaticism consists in redoubling your efforts when you have forgotten your aim." This last is something that we who wish to improve our craft would do well to remember.

What do you all think?

Thursday, 14 May 2009

Jaw-Droppers - Blast from the Past

Just when you thought it was safe to forget that the 1970s ever existed... this gem shows up on the XML Daily Newslink, a mailing list I follow intermittently. (Actually, this was included in the XMLDN from Wed 11 Feb — an indication of how "closely" I've been following lately.)

Developing a CICS-Based Web Service
G. Subrahmanyam, G. Mokhasi, S. Kusumanchi; SOA World Magazine

Web services have opened opportunities to integrate the applications at an enterprise level irrespective of the technology they have been implemented in. IBM's CICS transaction server for z/OS v3.1 can support web services. It can help expose existing applications as web services or develop new functionality to invoke web services. One of the commonly used protocols for CICS web services is SOAP for CICS. It enables the communication of applications through XML. It supports as a service provider and service consumer independent of platform and language. SOAP for CICS enables CICS applications to be integrated with the enterprise via web services as part of lowering the cost of integration and retaining the value of the legacy application. SOAP for CICS also comes along with the implementation encoder and decoder.

"SOAP for CICS"? Give it a REST, guys. On the other hand.... preserving this by-now more-solid-than-most-rocks 1969-era technology IS a signal achievement; an example of engineering stability on par with Soyuz.

On the other hand... support for legacy technologies like this looks set to become increasingly expensive and risky over time, since apparently:

  1. Numerous surveys published in the last few years indicate that the sizable majority of "old mainframe" tech folk will have retired by 2010 (do the math on the years), and

  2. partly as a result of (1), users risk become increasingly dependent on outsourced Indian providers — hardly conducive to effective project control.

In my own professional view, technological preservation activities like this are mainly useful for one thing: they can serve as the pattern against which a re-implementation of the business process using more currently-supportable tech can be verified. And once an organization has done this for its most valuable legacy systems (which wouldn't have been preserved this long if they weren't so valuable), the actual and perceived risk of migrating to new technologies as conditions warrant drops dramatically. After all, if you (or your internal colleagues) have successfully brought your line-of-business systems from CICS via REST to, say, PHP or Java, you're a lot more comfortable with the idea of migrating to whatever the mid-to-trailing technology is in ten years' time — while the support costs of the (then) existing system are still manageable.

Are any of you actually involved in any technological archaeology like this? When I was younger, I used to brag that half the systems I'd worked with were older than I was, but that stopped being true about 1995. (AFAIK, I was one of the last guys to professionally touch a working IBM 360 mainframe, in about 1989.)

(Original article at this entry's title link, which is also here.)

Wednesday, 6 May 2009

Professionalism, Web development, and giving oxy to morons

Whereas a poor craftsman will blame his tools, poor tools will handicap even the most skilled craftsman.

As I insinuated in my previous post, I'm getting up to speed on the Zend Framework, the "900-kg elephant" of PHP application frameworks.

One major bone I have to pick with the ZF team is with regard to documentation: each time I've checked the site in the last couple of months, there's been an apparently current HTML version (now clocking in at some 300 HTML pages). There is also a PDF version, the promise of which is used as an enticement to register for their content distribution network (and, presumably, marketing info). As of this moment, however, the framework is at version 1.8.0, but the PDF version of the programmer's reference manual only covers version 1.6.0 (from September, 2008); some 12 releases earlier. It no longer fully matches the actual code, to the point where it is not difficult for a new developer to get deeply confused.

After spending a half-hour browsing the HTML version of the document, I am unable to find any declaration as to which version of the Framework is documented. However, the README.TXT file included with the source distribution states that it covers the 1.8 release, revision 15226, released on April 30, 2009. Classes which are listed in the README as being new, such as Zend_Filter_Encrypt, are documented in the HTML programmer's guide. Establishing a match between the (HTML) doc and the current code is non-trivial, however. While it may be argued that people unfamiliar with browsing a Subversion repository are not likely to be common within Zend's target audience, I would indirectly refute that: a product release, particularly one with a strong industry following, should be

  • properly documented;
  • easy for a (prospective) user to verify that he has the complete package; and
  • with a definite, intuitive learning curve.
In my view, the Zend Framework fails on at least two of these points. The assertion within large segments of the PHP community that it is the "gold standard" of PHP application frameworks should be a disturbing, cautionary omen: if Web development, particularly PHP development, wishes to be taken seriously by the software industry at large, then some major improvements and attitude shifts need to occur quickly, publicly and effectively. It is still far too easy for potential developers outside the "early-adopter" leading edge to scoff that PHP development (and, by extension, Web development as a whole) is still far too immature and amateurish to be taken seriously. As someone who has developed professionally in PHP for some ten years now, that is a disturbing state of affairs; one that I would love to see (and participate in) a free-ranging discussion of.