Build it Yourself — Chatbot API with Keras/TensorFlow Model

Is not that complex to build your own chatbot (or assistant, this word is a new trendy term for chatbot) as you may think. Various chatbot platforms are using classification models to recognize user intent. While obviously, you get a strong heads-up when building a chatbot on top of the existing platform, it never hurts to study the background concepts and try to build it yourself. Why not use a similar model yourself. Chatbot implementation (more...)

Hide Pagination if one page results – Oracle APEX

I love this period of development not long after an APEX upgrade, where I discover all these little improvements that will help us out. Stuff that's not quite noteworthy in the wonderful read that is the new features guide (that's not sarcasm. Read it. Now.)

Recently I made an observation regarding a handy new template option, one that hides pagination if there is only one page of records. I've had a bit of jQuery (more...)

Oracle JET Table with Template Slots for Custom Cells

Oracle JET table comes with template slot option. This is helpful to build generic functionality to render custom cell within the table.

In this example, custom cells are used to render dates, amount and risk gauge:


While implementing Oracle JET table it is a best practice to read table column structure from a variable, not to define the entire structure in HTML itself. Property columns refer to the variable. Template called cellTemplate is a default (more...)

Cross Field Form Validation in Oracle JET

JET keeps evolving and in the latest versions  - toolkit provides improved support for form cross-field validation. It is much easier to implement validation than it was before. I will show it in this example.

Example of the data entry form. Validation logic:

- Invoice Date before Payment Due Date and Payment Date
- Payment Due Date before Payment Date


Example when two fields fail validation:


JET provides component called validation group. Form can be (more...)

Search Form in Oracle Visual Builder based on ADF BC REST

Oracle Visual Builder supports ADF BC REST out of the box. Build service connection using "Define by Specification" wizard:


Wizards support ADF as API type. Add describe at the end of the REST URL, this will bring metadata for exposed ADF BC REST service (information about attribute types, etc.):


List of endpoints will be populated automatically. You could select all endpoints to be supported for your connection or select only few:


The most typical (more...)

Oracle Visual Builder 18.4.5 and JET 6 Support

Oracle Visual Builder 18.4.5 comes with very neat and polished UI. Also it brings Oracle JET 6 support (latest JET version to date). Read more about it - New Features in Oracle Visual Builder December Release.

I have upgraded our VBCS instance to 18.4.5:


I was curious how automatic upgrade would work for VBCS app implemented in the previous version (download source code for the upgraded app from my GitHub repo). (more...)

Knockout.js – Updating Single Array Element (Oracle JET)

If you implement tables and using Knockout.js to push data updates from JS to HTML - probably you experience a situation when it doesn't work to push an update for one of the columns. I mean you could replace the whole observable array element - this would cause full row refresh. But visually this doesn't look nice and why to refresh the whole row, if only one (or few) element (-s) from the row must be refreshed.

(more...)

Off Canvas Menu in Oracle VBCS/JET Cloud

These days I'm actively working with VBCS/JET Cloud product from Oracle. The more I work with VBCS the more I like it. VBCS follows similar declarative development concepts as Oracle ADF, this makes it easy to get up to speed with VBCS development. VBCS with declarative JavaScript development approach brings unique solution for JavaScript systems implementation for enterprise.

I will share sample with off canvas menu implementation for VBCS app. Sample is based on step (more...)

Date Format Handling in Oracle JET

Oracle JET comes with out of the box support for date converter, check more about it in cookbook - Date Converter. This makes it very handy to format dates in JavaScript. Here is date picker field example with yyyy-MM-dd format applied:


When button Process is pressed, I take date value from date picker and add one day - result is printed in the log. This is just to test simple date operation in JavaScript.

Date (more...)

Notification Messages in Oracle JET

Let's take a look into cool component available in Oracle JET - notification messages (it is possible to display messages in different ways - inline or overlay. Check more about messages functionality in JET Cookbook example).

This is how notifications messages are showing up, very cool way to send information to the user:


Messages are implemented with oj-messages components. This component accepts observable array of messages to be displayed. We can specify how message (more...)

await in turn by mistake

I really enjoy working with the new async functions but it is really easy to set up a situation where code that could be running in parallel is force to run in sequence. Consider this simple invocation of a javascript function that takes two values returned from other async functions:

   const combination = await combine(await value(1), await value(2));

The problem here is that unless the JS environment does some optimisation for you, the actions contained (more...)

Oracle ADF + Jasper Visualize.js = Awesome

This week I was working on a task to integrate Jasper Visualize.js into Oracle ADF application JSF page fragment. I must say integration was successful and Jasper report renders very well in Oracle ADF screen with the help of Visualize.js. Great thing about Visualize.js - it renders report in ADF page through client side HTML/JS, there is no iFrame. Report HTML structure is included into HTML generated by ADF, this allows to (more...)

Amazon SageMaker Model Endpoint Access from Oracle JET

If you are implementing machine learning model with Amazon SageMaker, obviously you would want to know how to access trained model from the outside. There is good article posted on AWS Machine Learning Blog related to this topic - Call an Amazon SageMaker model endpoint using Amazon API Gateway and AWS Lambda. I went through described steps and implemented REST API for my own module. I went one step further and tested API call (more...)

Managing Persisted State for Oracle JET Web Component Variable with Writeback Property

Starting from JET 6.0.0 Composite Components (CCA) are renamed to be Web Components (I like this new name more, it sounds more simple to me). In today post I will talk about Web Component writeback property and importance of it.

All variables (observable or not) defined inside Web Component will be reset when navigating away and navigating back to the module where Web Component is included. This means you can't store any values (more...)

Lazy Loading Menu

I've been using the lazy loading concept demonstrated in Maxime's post quite a lot recently, I'd love to see this as a declarative feature one day.

I also wondered if I could apply this concept to the badge count in the side menu.


Turns out it wasn't that hard, particularly since I already had the jQuery I needed from a previous requirement.

We first need to add a unique class to the link definition, so (more...)

TypeScript Example in Oracle JET 6.0.0

JET 6.0.0 officially supports TypeScript, wow that great news. If you are building large JavaScript application with JET, it will be much easier to manage code with TypeScript - it does type checking and reports code errors during build time. Logic can be encapsulated into classes with inheritance. Read more about classes support in TypeScript.

In this post I will share simple JET application enabled with TypeScript support. Sample application can be downloaded (more...)

Oracle Offline Persistence Toolkit – Applying Server Changes

This is my final post related to Oracle Offline Persistence Toolkit. I will show simple example, which explains how to apply server changes, if data conflict comes up. Read previous post about - Oracle Offline Persistence Toolkit - Submitting Client Changes.

To apply server changes is easier, than to apply client changes. You need to remove failed request from sync queue and fetch server data to client by key.

Example of data conflict during sync:


(more...)

Oracle Offline Persistence Toolkit – Submitting Client Changes

One of the key topics related to Oracle Offline Persistence toolkit - submitting client changes to backend when data conflict exists. If data was updated on the backend, while client was offline and client wants to submit his changes - we inform about the conflict and ask what client really wants to do. If client choose to submit changes, this means we should push client changes to the backend with the latest change indicator.

There (more...)

Understanding ordering with JavaScript async methods

So I challenged someone in a code review to prove that there code that made use of async functions wouldn't be susceptible to a race condition. To that end I came up with a very trivial code example to demonstrate the issue, worth trying to write down the output and line orderings before you read on.

let list;

async function clearList () {
    list = []; // A
}

async function processList (processList) {
   await  (more...)

Oracle Offline Persistence Toolkit – Before Request Sync Listener

One more post from me related to Oracle Offline Persistence Toolkit. I already described how after request listener could be useful to read response data after sync - Oracle Offline Persistence Toolkit - After Request Sync Listener. Today will explain when before request listener could be useful. Same as after request listener, it is defined during persistence manager registration:


Before request listener must return promise. We can control resolved action. For example if there is (more...)