Development Improvements, June 2013

Tue Jun 04 13:05:38 EDT 2013

Tags: development

I'm always looking to improve my programming/development/administration methods, and in the past couple months I've made a few more changes. To my chagrin, these changes are mostly things that I should have been doing for a while now and I've been sloppy to do them differently, but hey - fixing a problem is still improvement!

Serious About Source Control

I've been using source control for a while now, and I hope everyone else has as well. However, I've been lax in a couple ways, which bit me a while ago. For example, I had a couple actively-used projects tied to source control in Designer - a few NSFs, a few NTFs. That was fine NORMALLY, but then this sequence of events happened:

  • I run Designer in a Parallels and have my repositories stored Mac-side, pointed to via a drive-letter mapping to my home folder
  • I Remote-Desktop'ed into my Windows VM from another machine
  • Remote Desktop remapped the drive letters to share local resources
  • Designer, which was running at the time, could no longer find the repository folders
  • Apparently, Designer/eGit/whatever decided that the rational thing to do was to "sync" the NSFs with the now-missing repositories... which is to say, delete all design elements from the NSFs

Imagine my surprise when a previously-fine DB I hadn't intentionally touched in a while was suddenly naked, consisting of a single view that somehow survived the purge. Fortunately, the nature of the problem meant that the design was still stored in the repository and thus recoverable, but that's still not a problem you want to have.

So I've been shifting my development process another few steps closer to the ideal. The way I see it, that ideal is:

  • Never open a production DB in Designer
  • Do all development in entirely-distinct NSFs created either from scratch (for a new project) or via the "Associate With New NSF" action from the source-controled on-disk project. These NSFs should be worked on by a single person and should either be in an individual-user dev folder on the server or, better, on a local development server
  • Create deployment "builds" as NTFs, either as design-only copies of a source-associated NSF or, again, from the "New NSF" action from an on-disk project (but it should then be disassociated immediately)
  • "Deploy" the "builds" using Replace Design on the production NSF/NTF from the Notes client or, better, Administrator
  • Ideally, the "build" NSFs should closely match a tag or branch in the source repository, but I can't be bothered to do that for my needs yet

That process goes the same for "classic" and XPages apps. Since source control became viable for Domino devs around the same time as XPages hit the scene, the two are often conceptually tied together, but in my experience the classic binary-DXL handling is plenty good enough to use it in projects without a line of Java or XSP.

Separate Application and Data

The standard way to develop a Notes app - classic or XPages - is to bundle the design and data together. This has historically had a lot of benefits and still makes sense in some cases (say, customizing individual mail files for different uses). However, particularly in the case of a standalone "app" (a help-desk application, a project-tracking system, etc.), this tight joining makes little sense and would be considered a bizarre aberration by anyone using most other systems.

Fortunately, as Domino developers, even if we split up the design and data, we still have it easier than most, since we don't have to worry about drivers and authentication credentials for the back-end DB (unless we want to). In the simplest case, which I've adopted, you have your "app" NSF and a "data" NSF next to it. The "app" NSF contains no forms or views, which the "data" NSF contains no XPages, Java, or other "executable" entities. I've derived a couple benefits from this already:

  • The app and data NSFs can have different ACLs
  • The data NSF can be set to disallow URL open. This means you don't have to worry about, say, clever users trying ?ReadViewEntries to peek into more than they should see
  • You can easily switch between "dev", "production", and "test" data NSFs, just like normal developers do. You don't have to worry about copying data around between different dev versions of your app
  • Multiple apps can point to the same data with impunity
  • The data NSF can exist on another server... or cluster of servers, which you could switch between programmatically
  • Data sharding becomes easier. Depending on the type of app, each user/project/department/whatever could have a different backing NSF fronted by the same single app

Admittedly, this makes some things moderately more complicated. Any Domino data sources will need to have a databaseName property specified, which will need to get its value from somewhere (worst case, you could hard-code it to start with, then "upgrade" to a managed bean). You also won't be able to use "app.nsf/view/key"-style URLs, since the app won't have any views to search by - you'll have to use query parameters or cobble together your own good-looking URLs with the assistance of Web Rules. You might not want to make your structure too document-focused anyway.

 

These changes have been bringing my development closer to classic desktop-app development, where these are less "techniques" and more requirements due to the nature of development, but they've proven to be valuable. Domino's ease of getting started and fast-and-loose development methods have distinct advantages, but it's always important to question which ones are better than other environments and which are traps.

New Comment