App Dev After CollabSphere 2018

  • Jul 29, 2018

In recent years, MWLUG/CollabSphere has tended to be a good time to get a lay of the land for what IBM - and now HCL - intends for their app dev strategy. Recent Connects weren’t too heavy on announcements of major import for Domino developers, and any news to come out tends to do so in the months leading up to summer.

This year, we’ve had time to digest the implications of the HCL transfer, get a feel for how they intend to handle the product, and generally get a good bead on their app-dev vision. What they’ve said so far this year is clear: LotusScript for old apps on mobile platforms and Node.js for new development (or new developers). As far as XPages, I believe that the most time that it got at the conference was in my session, which was about what to do after XPages.

LotusScript

Though I’ve certainly not hidden how painful the prospect of enhancements to LotusScript is to me, I have to admit that adding a few capabilities for REST data service access makes strategic sense for the platform. Though XPages made a significant mark on Domino app dev, it never pushed aside the classic style, and every move that IBM made for app modernization since then seemed to exist exclusively in the span of the sentence announcing it.

So HCL announced early this year that they planned to port the classic Notes client first to iOS and then later to Android and WebGL+WebAssembly. Adding any kind of Java to this plan - XPages, LS2J, etc. - would present some technical hurdles, and so it makes workload sense to focus on the languages that have runtimes in the C core.

Apps run this way won’t be good, but there’s some logic to the tack of targeting customers for whom “modernization” only really means “we want our same old apps to run offline on new OSes”. Their plan to run on phones also necessitates some more-dramatic changes to the tooling, so it’s possible that they have larger changes in mind - or at least we’ll see a return of the “hide on mobile” checkboxes in Designer.

Node.js

The big HCL push for Node.js seems to me to be a way to get a lot of bang for the buck: by positioning it as the new way to write apps, they’re both (potentially) making Domino more appealing to those not already on the platform and guiding existing developers to a platform for which IBM and HCL are not responsible. Though the domino-db driver is no small technical feat - and it looks like they’ve done a good job making it both fast and native-feeling in Node - it’s a much, much smaller footprint than XPages, which put IBM on the hook for maintaining an entire app-dev stack and UI toolkit with limited outside assistance.

I do think that it’s smart to write a Node.js DB driver - even if it doesn’t bring in an influx of new blood, it provides a legitimate app-dev story and Node is a top-notch platform. The gRPC stack also provides an entryway for future hooks and development without the assumptions of NRPC.

Java

Java development on Domino is in a weird place. Domino 10 doesn’t have anything directly for XPages/OSGi developers, though we’ll get access to DGQF via the Database class. I’ve heard whispers that they’re starting to plan more for Domino 11, but that’s largely conjecture at this point. Certainly, HCL has made it clear that their heart isn’t in it, and honestly I get why. Since XPages has been in essentially maintenance mode since 9.0.1 or earlier, it’s aged itself out of contention for modern app dev. It wouldn’t be impossible to drag it forward to something respectable, but then they’d still have another development environment exclusive to Domino to maintain.

I’m not sure what the best thing to do with the stack is. Though XPages didn’t bring all Domino developers to it, it did bring a significant chunk, and a lot of people have spent upwards of a decade of their life with the toolkit. For my part, I think it makes a lot of sense to move to “normal” Java/Jakarta EE development, which provides the possibility of salvaging Java-side code, though it leaves XSP and SSJS in the lurch. It’s hard to make a good financial case for either significantly upgrading the platform or at least undoing the tight coupling with the Domino server that it accrued over the years, though I’ll admit it’s sort of fun to think about.

DGQF and DQL as I Understand Them

  • Jul 26, 2018

At CollabSphere this year, the big information coming from HCL was detail about the Domino General Query Facility (DGQF) and its associated language, Domino Query Language (DQL). They originally announced this a few weeks ago, but it was good to have had some time to let the dust settle and to see the specifics.

Because it was discussed alongside the domino-db Node.js package and because it's one of the first real new ways we'll interact with data in a Domino DB in a while, it's a bit difficult to identify just what it is and what it is not. Here's how I understood it:

What DGQF Is

DGQF is, at least conceptually, a "meta" layer on top of the existing NIF indexing facility. It doesn't provide a core change to the actual storage of documents, but instead treats existing view indexes as (roughly) analagous to both SQL table indexes and SQL views. It trawls through the design elements of a database to analyze their selection formulae and columns to use applicable ones as implicit indexes and also to allow access to arbtirary collections within queries.

Implicit Indexes

Other than the design collection and the "optimize document table" option in a DB, an NSF doesn't really have much in the way of indexing note contents by default. So, if you have a query asking for all documents where FirstName is Bob, a program has no choice but to look through every document for that key/value match. If, however, you create a view that has a column showing the FirstName field, you now have a much-faster index you can use. It's this sort of view that the DGQF picks up on implicitly, using them to accelerate queries: views showing all documents with either a default sort or "click to sort" column showing explicitly a field (and not a formula).

Access to Arbitrary Collection Data

For those qualifying views plus others, you can reference a view by name or alias to compare to a column value by programmatic name (often either the field name for simple columns or something like $4 by default for formulas).

"In" clauses

Additionally, you can use view (and folder, I think) names to refine queries for documents that are in one or more of these collections, equivalent to an "in" subquery or view reference in SQL

What DQL Is

In short, DQL is the human-readable query language used to access DGQF. It's reasonably SQL-like (though it is not SQL) and tends to look like FirstName='Bob' and in all ('Managers', 'Active Users'). This is the language you will use, and so "DGQF" and "DQL" will generally refer to the same thing in practice.

In practice, this is implemented as a new method on the Database class in each high-level language supported by Domino, plus a Node-styled variant in domino-db.

What DGQF and DQL Are Not

Since DGQF sits on top of NIF (and probably the FT index eventually), it's not a core change to data storage. Eventually, the same abilities and limits of Domino remain as they are with respect to this.

Additionally, DQL is, I believe, a query language only: it does not provide a mechanism for creating, modifying, or deleting existing documents. Instead, it is essentially a super-powered and much-smarter version of database.search(…): you can use it to find documents and the processing of them is up to your program.

That last point was a bit muddied by its pairing with the domino-db Node.js package: the Node.js package provides bulk operations that are paired with DQL queries, but that is a function of that library specifically, not DQL or DGQF.

Why It's Cool

Though it's not a reworking of the core NSF, what DGQF does do is abstract away a lot of the manual looping and lookups that we've always had to do, and it allows the system to optimize and do things more efficiently than when written out procedurally. So, while there's theoretically nothing that DGQF does that we couldn't do before, it allows us to do those things with far, far less code and with automatic optimization.

This brings Domino something that SQL servers have enjoyed for a long time. With a SQL statement, you can analyze the trouble spots of a slow-running query and add indexes to improve the speed, with the tooling helping to explain what's going on. DGQF+DQL brings this along for the ride: when you execute a DQL query, you have the option to dump out this "explain" output to see what specifically the facility did, which views it used, and how long each step took. So, if you have a long-running query, you can look to see if you can add an "index" view to automatically speed it up without having to change your code. And, since the language is an abstraction over the task of querying and not the sort of "burned in" process of a normal getNextDocument loop, it can be optimized and short-circuited by the underlying system without the developer having to know the decades of built-up knowledge of how to efficiently search a DB.

All in all, this is a very welcome addition to the server, and it certainly should improve a lot of common tasks.

Reforming the Blog in Darwino, Part 4

  • Jul 20, 2018

Last time, I went over my switch in tack for how I'm making the new version of my blog, and my overall focus on picking an interesting stack of JEE technologies. In this post, I'm going to start diving into the implementation of the UI, though I think that it will make sense to dedicate two posts to it.

The biggest decision I made with the UI side of this app is that I didn't want to make a client-side JS app. There's a reason they're so ascendant, and I find development with React or Stencil pretty enjoyable, but I wanted to go a different route here for a few reasons:

  • For a blog, a CSJS app is wildly overkill, and, in fact, would require extra work to fulfull one of the basic requirements of a blog, which is being web-crawler friendly.
  • I want to see how svelte I can make the client payload.
  • Skipping a JS framework (and a CSS one) is a great way to brush up on what plain HTML and CSS are capable of nowadays.
  • Unlike a typical Darwino app, my only target is a full-on Java web server, so I'm not held back on the Java side by the capabilities, say, of Dalvik on Android 4.
  • Part of me misses the simplicity of my early PHP days, albeit not the language.

The Java Side

I decided to go with the MVC 1.0 draft spec because it lets me write extremely focused code. Here is the controller for the home page:

package controller;

import javax.inject.Inject;
import javax.mvc.Models;
import javax.mvc.annotation.Controller;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

import model.PostRepository;

@Path("/")
@Controller
public class HomeController {
	@Inject
	Models models;
	
	@Inject
	PostRepository posts;
	
	@GET
	public String get() {
		models.put("posts", posts.homeList());
		
		return "home.jsp";
	}
}

Naturally, there's a lot of magic going on behind the scenes - there's tons of heavy lifting going on here by JAX-RS, MVC, CDI, JNoSQL, and Darwino - but that's the point. All the other components are off doing their jobs in their areas, while the code that provides the UI doesn't have to care about the specifics.

Things can get more complicated on the pages that actually have some functionality to them, but the code remains pleasantly focused. Take the handler for deleting posts:

@DELETE
@Path("{postId}")
@RolesAllowed("admin")
public String delete(@PathParam("postId") String postId) {
	Post post = posts.findByPostId(postId).orElseThrow(() -> new IllegalArgumentException("Unable to find post matching ID " + postId));
	posts.deleteById(post.getId());
	return "redirect:posts";
}

This adds another level of magic in the form of javax.security.annotation.RolesAllowed, but it's more of the good kind: even with no knowledge of the underlying frameworks, it's pretty clear what every bit of code is doing here. It's a refreshing bit of that Rails simplicity, just more compile-type-safe and much uglier.

Even beyond the minimal code is the cleanliness that this brings to the structure of the application: other than the img, css, and js paths, all of the routing within the application is done care of JAX-RS and MVC. It's not beholden to the folder structure in the project or to a Domino-style implicit app router.

JSP

JSP has been the prototypical Java HTML language for about 20 years, and it's had a rough upbringing. The early versions committed the PHP/XPages sin of encouraging you to put business logic right on the page, and it even still has the typical Java problem that it's tricky to find advice about using it that uses technologies added since 2005.

Still, when used properly, it can be a nice, clean templating language. Again from the main home page:

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<t:layout>
	<c:forEach items="${posts}" var="post">
		<t:post value="${post}"/>
	</c:forEach>
</t:layout>

For an XPages developer, this is extremely comfortable. It's also very refreshingly elemental: there's no server-side persistence of the page, so everything is "load-time bound" and, with just HTML tags and core JSTL tags, nothing ends up on the page that you don't explicitly put there.

Ozark, the MVC implementation, also supports using JSF "Facelets" for the view portion, but JSP suits the task just fine.

HTML + CSS

It'd been far too long since I last really sat down and looked at what baseline HTML and CSS are like - in particular, I'd watched the rise of CSS Flexbox and Grid from afar, and never gave them a shot. Using components that generate their own HTML and pre-existing CSS frameworks to target with class names is all well and good, but it does leave you a bit disconnected from the fundamentals.

So, for this iteration, I tossed aside the very-nice Bootstrap framework I've been using, dusted off one of my old hand-built ones, and got to translating it into CSS Grid. This cut down on the page size enormously: I had already echewed Dojo by not using XPages, but this now also meant that I could ditch the core bootstrap.css, jQuery, and any jQuery plugins.

Beyond CSS Grid, have you seen how nice HTML forms are nowadays? Just looking at this post reveals how much is built in in the way of validation and different input types, even before you write a line of JavaScript.

Turbolinks

Having such a trimmed-down UI means that pages already load extremely quickly, but I figured this was also a perfect chance to try out a bit of clever tech from the team at Basecamp: Turbolinks. Turbolinks is a JS file that you bring into your app which then transparently takes over your in-app links to minimize the amount of rendering you have to do. Since the surrounding boilerplate of the app usually doesn't change between requests, it can figure out the "diff" between old and new and just replace the body. It's essentially like partial refreshes without the server knowing anything about it.

It's still technically inefficient to have the server render and transfer surrounding page elements that are just going to be discarded anyway. But, on the other hand, skipping that means that I don't have to write JavaScript handlers myself, use a full CSJS app framework, or keep state on the server side. The server just keeps doing what it does with a fully context-less request and the browser sorts it out. Basecamp's programmers are masters at the targeted deployment of kludges for maximum benefit.


In the next (final?) post in the series, I'll finish up with my "low-JS" experience and other lessons learned from this project.

Reforming the Blog in Darwino, Part 3

  • Jul 18, 2018

A good while back, I created a project structure for reforming my blog here in Darwino, but, as happens with low-priority side projects, it withered on the vine, untouched since then. Beyond just the "cobbler's children" aspect to it, I also lost steam due to a couple technology paths I initially headed down.

The first was basing the UI on Angular, which I've never really enjoyed working with. I'm sure I could have ended up with a decent result with it, but Angular always rubbed me the wrong way. And not just Angular: for a dead-simple UI like this, a full JS UI is just weird overkill.

The second was off in the other direction: I initially tried cramming a Rails app in the tree, which could be made to work, but it introduced so many weird edge cases outside of the problem at hand. That alone isn't the end of the world, but not much of what I'd have to solve to make that work would be transferrable elsewhere any time soon, so it'd end up a real time sink.

So, taking what I've learned since and the projects that I've been working on, I've decided to take another swing at it. Before I get into the implementation side, it will be useful to go over the technologies I did choose for the new form.

Java/Jakarta EE

I've recently become kind of enamored with the modern form of the Jakarta EE stack, and so I decided to use this as an opportunity to really dive in to what a blue-ocean small by-the-books Java app looks like nowadays.

JEE got a well-deserved bad rap over the years for its configuration complexity and general impenetrable-ness, but I've been very pleased to find that those tides have largely receded. It's all still there if you want it, but a fresh new app primarily consists of decorating a handful of Java classes with declarative annotations.

JEE consists of a series of individual specs, and building an app involves choosing which ones you want to use, plus (depending on which you choose) picking your app server target.

Tomcat

I originally gave a shot to adding enough OSGi metadata and bundles to target Domino, but decided quickly that it was just not worth it. The HTTP/servlet stack in Domino is just so old that, even if I got everything bound together, I'd still be fighting the platform every step of the way.

The better route was to put it aside and just run a modern Java app server. I went down the list of GlassFish, Payara, WebSphere Liberty (the nearest miss), TomEE, and WildFly, but each one ended up having some problem with either the dependencies I wanted or with their Eclipse integration. I ended up settling on good ol' reliable Tomcat. Tomcat itself isn't actually a JEE server, but it's kind of like a Raspberry Pi: it gives you the baseline for a Java servlet engine, and then you can cobble together your own EE stack on top of it by explicitly bringing in implementations. Though the final .war file is far less svelte this way, I found that this build-your-own method results in the lowest chance of being held back by the platform currently.

As an aside, Sven Hasselbach has been writing a very interesting series on running Jetty on top of the Domino JVM to achieve a similar end, albeit with Spring.

Darwino

For all the same reasons as when I set out on this journey originally, I'm using Darwino for the baseline. This lets me replicate in my existing blog data smoothly while getting the advantages of a superior backing database. I'm not making use of mobile clients or most Darwino services with this, but the baseline is nonetheless a step up, and fits in with a JEE app like a glove.

JNoSQL

I brought in the JNoSQL Darwino driver I wrote a little while ago to handle the model layer. JNoSQL is essentially JPA but reformed for NoSQL access - no cruft, no relational/NoSQL impedence mismatch, and designed to fit with current JEE technologies.

CDI

CDI is one such technology, and it's a very interesting one to work with. The whole "dependency injection" realm is a little fraught and, if my Eclipse UI error reporter is any indication, prone to bizarre errors, but the core concept is good and very useful. I've gotten it into the swing of using it both as the "managed bean" provider for the front end as well as the general service provider glue for the app. It still takes some getting used to, and the learning curve falls prey to a similar problem as when I was learning Maven: something about learning how it works makes you forget what it was like to not know, and so a lot of the answers online assume way more knowledge than a neophyte has.

Bean Validation

I've long been a fan of the Java bean validation API, and it's a clean fit here too: JNoSQL picks up on the presence of Hibernate Validator without configuration beyond the dependency and it just works. No muss, no fuss.

JAX-RS + MVC Spec

JAX-RS is at this point familiar territory for a lot of Domino developers, but I decided to use it as the underpinnings of the whole UI, in tandem with a draft framework called MVC 1.0. The latter's generic name doesn't really give much detail, but it's essentially a spec that enhances JAX-RS entities with knowledge of HTML templating frameworks, allowing you to write a very clear app structure. It's not a server-state-based framework like JSF, but rather a bit "closer to the metal", where you deal directly with the HTTP method cycle.

As I'll go more into in the "UI" post, it's been surprisingly refreshing to get back to basics in this way - JSF/XPages is often a bit conceptually easier to work with (at first) and client-side JS frameworks have some REST+JSON purity to them, but just "this server-rendered HTML page with no server state is everything you need" feels really good sometimes.

Admittedly, the MVC spec itself is in a weird place. It was originally a candidate for inclusion in Java EE 8, but was dropped in the final runup. It's possible that this will prove to be a kiss of death, but the spec is so small but functional that I don't feel bad about taking the risk of building an app on it.


That about covers the technology stack. When I get around to writing the next post, I'll go into some of the specifics about how I decided to set up the UI, which has been a fun experiment of its own. In the mean time, the active repository is up at:

https://github.com/jesse-gallagher/frostillic.us-Blog/tree/develop/frostillicus-blog

A (Java-Centric) Domino Wish List

  • Jul 12, 2018

Seeing the information come out of this week's HCL "Golden Ticket" event has got me thinking about some of my wish-list items for Domino development, mostly in the form of enhancements for existing capabilities and entirely around Java (since that's what I do).

Quality of Life

Javadoc

For some reason, the lotus.domino classes ship without Javadoc or even variable-name information, leading to this trainwreck:

Designer has its built-in help, which is also on the web, but that's quite a few steps down. This is table stakes for a Java API and always has been.

Updated p2 Repository

Back in 2014, the XPages team uploaded a clean p2 repository of the XPages artifacts to OpenNTF, corresponding with the 9.0.1 release. This repository saves a ton of hassle when building Tycho-based projects or just setting up an Eclipse workspace. However, it's quite long the tooth, as there have been several Notes.jar additions not included in there, and, in FP10, a significant upgrade to the undergirding OSGi framework.

I ended up writing a script to generated an updated version, but I don't have the legal ability to publish the results anywhere for easy consumption, meaning it has to be done manually and configured for each build environment. It would be a great convenience if there was an official package (ideally including the Designer plugins as well) and, even better, hosted on OpenNTF so that we could reference it by URL as we do for Eclipse releases (and require users to accept a license first).

Mavenized Repository

The p2 repository is good for Tycho-based projects, but, especially when targetting Domino is only one part of a project, it can be much more convenient to use "normal" Maven projects with maven-bundle-plugin. However, those projects can't use p2 repositories as such. For Darwino's needs, I ended up writing a tool in the (available-for-free) Darwino Studio plugins to Maven-ize a Domino p2 repository, but that hits the same snag as above of requiring manual setup in each instance.

This is another case where my preference would be on the OpenNTF Maven repository (plus Javadoc Jars, naturally).

Extension Library Source

The latest Extension Library release on OpenNTF is from FP9, while the latest on GitHub is from the FP7 era. FP10 shipped with a newer version of indeterminate nature. It'd be good to have this on both of those sites and, like with Javadoc, have source bundles shipped with the product in a way that is picked up automatically by Designer and Eclipse.

Source Bundles for Third-Party Components

The source for the undergirding Equinox stack is available, but it would be best to have, as an adjunct to the updated p2 repositories, the source bundles for the actual versions used so that we don't have to cobble together a platform from Eclipse's repositories.

Open-Source the Rest of the Stack

Having XPages, the Expeditor husk, and the other miscellaneous doodads that make up the proprietary layer as open source with an Apache-compatible license would cover a lot of the above and also be of tremendous use for XPages and non-XPages apps alike that run on or with Domino. I have a hard time imagining that it would lead to a lot of community-driven improvement, but it may do some (I'd have a few words to share with the file-download control, for example), and even just as a static release would be a significant boon.

Domino Connectivity in Eclipse

An idea I've been toying with lately is to make an Eclipse plugin that allows you to add Domino servers to the "Servers" view and control them to some extent. The basics would be to start/stop/restart HTTP, but the stretch goals would be to open a console view, get a list of running modules, integrate with the existing "load bundles from PDE" support, and, ideally, an outright "Run on Server" command for OSGi bundles and NSFs. However, I have so much on my plate that I'm not sure that I'll get to this any time soon unless I get a real itch some weekend.

Longevity

Refreshed JVMs

Feature Pack 8 brought Java 8, a vital step forward. However, since then, Oracle moved to a faster release cycle for Java and the JRE is now at version 10. Domino uses IBM's JVM variant, J9, which they recently moved to the Eclipse foundation as OpenJ9, where it has... sort of been keeping up, I think?

In any event, this increased pace of change has meant that the Java 8 honeymoon is over, and Domino development again requires special consideration when using current tools. I have no idea how complex the integration between Domino's tasks and the underlying JVM is, but my ideal would be to have constant or near-constant parity.

Servlet API 4.x

After the JRE version, the most important foundational element of a Java web app is the servlet API release. The current version is 4.0.1, while Domino supports 2.5 (or 2.4, maybe?). The good news is that the Java/Jakarta EE world seems to be used to lagging versions here, and 2.5 is a minimum version for a lot of current tech in much the same way that Java 6 was until somewhat recently, but there has been quite a bit added in recent years.

Presumably, a reason for the lag is the implied requirements of newer versions, such as WebSockets and HTTP/2 support, that would require heavy modifications to the core Domino HTTP code. Honestly, the more practical route is almost definitely to just use a different JEE server paired with CrossWorlds, some Java wrapper for the GRPC stuff HCL has been talking about, or (best of all) a Darwino app replicating with Domino, but still. WebSphere Liberty is actually really nice, by the way.

Refreshed Equinox

Like with the underlying JVM, the Feature Pack 10 update to a Neon-based OSGi/Equinox framework was a critical shot in the arm for the platform, but it is now also two major versions behind. This is a little less critical, since Equinox brings a bit less to the table for our needs and Neon is "new enough" for now, particularly on the server side, but it'd still be proper to keep pace.

Odds and Ends

Non-OSGi JEE Support

The Equinox framework that Domino uses is quite capable, but there's no pretending that OSGi-targetted development has its share of headaches. Most Java apps just target plain-old .war files and don't impose any particular requirements on the build process. Java development is a much more pleasant experience when you can just toss in any Maven dependency and not have to think about building a target platform for Eclipse or jumping through bundle-resolution hoops. I really like OSGi in theory, but I can't pretend that non-OSGi development isn't much smoother.

Domino technically supports "regular" servlets currently, but, uh, here's a snippet from the current documentation on that:

Hrm.

Full Extension Manager Support for Java

JAVADDIN/DOTS added a lot of EM hooks, but it doesn't cover the full suite of capabilities that a C addin can provide, such as authentication handling. Having this be fully accessible from Java would be useful even when treating Domino just as a data store and not as an app server.

 


 

I'm sure I could come up with more, but that's probably good for now. All easy, right?