Oracle JET – How To Reference JavaScript Module in HTML

I will explain how to reference JavaScript module function in Oracle JET HTML. In previous Oracle JET versions, we were using $root to access parent appController module. Syntax $root looks a bit like magic, it is better to reference module through a predefined variable. I will show you how.

Sample app comes with number converter, which helps to format numeric value. For convenience reasons and better reuse, number formatting function is moved to a separate (more...)

Oracle JET Model ID Attribute

When building Oracle JET Model/Collection structure to render table, you should be careful defining ID attribute. This attribute must have unique values only, if there will be duplicates in ID, then table rows will be rendered incorrectly.

Take as example below structure for Employees REST endpoint. EmployeId attribute provides unique values and it should be defined as ID for JET model:


Let's try and see what happens when non-unique DepartmentId attribute is set for a (more...)

Report Time Execution Prediction with Keras and TensorFlow

The aim of this post is to explain Machine Learning to software developers in hands-on terms. Model is based on a common use case in enterprise systems — predicting wait time until the business report is generated.

Report generation in business applications typically takes time, it can be from a few seconds to minutes. Report generation requires time, because typically it would fetch and process many records, this process needs time. Users often get frustrated, (more...)

Fix for Oracle VBCS "Error 404–Not Found"

We are using Pay As You Go Oracle VBCS instance and had an issue with accessing VBCS home page after starting the service. The service was started successfully, without errors. But when accessing VBCS home page URL - "Error 404--Not Found" was returned.

I raised a support ticket and must say - received the response and help promptly. If you would encounter similar issue yourself, hopefully, this post will share some light.

Apparently "Error 404--Not (more...)

Forecast Model Tuning with Additional Regressors in Prophet

I’m going to share my experiment results with Prophet additional regressors. My goal was to check how extra regressor would weight on forecast calculated by Prophet.

Using dataset from Kaggle — Bike Sharing in Washington D.C. Dataset. Data comes with a number for bike rentals per day and weather conditions. I have created and compared three models:

1. Time series Prophet model with date and number of bike rentals
2. A model with additional (more...)

Oracle ADF A Status Update

Oracle posted information update for Oracle ADF - "With the continuous investment and usage of Oracle ADF inside Oracle we expect external customers will also continue to enjoy the benefits of Oracle ADF for many more years."

Read the complete post here: https://blogs.oracle.com/jdeveloperpm/oracle-adf-a-status-update

Happy to read the update, sounds positive. Thanks to Oracle for taking time and publishing this information. #adf #middleware #javascript #oracle #cloud #oraclefusion

Serving Prophet Model with Flask — Predicting Future

The solution to demonstrate how to serve Prophet model API on the Web with Flask. Prophet — Open-Source Python library developed by Facebook to predict time series data.

An accurate forecast and future prediction are crucial almost for any business. This is an obvious thing and it doesn’t need explanation. There is a concept of time series data, this data is ordered by date and typically each date is assigned with one or more values specific to (more...)

Oracle Developer Tools – Do They Still Exist?

People are frustrated about @OracleADF @JDeveloper on social media - "ADF boat has no captain", etc. I agree @Oracle is to blame big time for such lame handling of its own Developer Tools stack. @Oracle please wake up and spend some budget on @OracleADF. Read more:

Oracle VBCS - right now this tool gets the most of Oracle focus. Supposed to offer declarative #JavaScript development experience in the Cloud. Not well received by the community. (more...)

Running Oracle JET as Progressive Web App

Progressive Web Apps (PWA) topic is a hot thing in web development these days. Read more about it - Progressive Web Apps. The beauty and power behind PWA - user can install a web app to his mobile device, without going through the app store. This simplifies update process too, when a new version of the app is available, the user will get it straight away, because it is essentially a Web page, wrapped to (more...)

Running Oracle JET on Heroku with Node.js (JET Showcase)

I have implemented JET (more about Oracle JET) showcase app with data visualization components usage. This app shows historical weather data in Boston city, the dataset is taken from Kaggle. Switching years makes data visualization to change and show new data - I love how polar chat is updated. Calendar displays temperature for each day during the year using JET picto chart component:


App is deployed on Heroku and available by this URL. Heroku (more...)

ADF Faces and Client Side Value with innerHTML

In ADF Faces you can leverage the full power of JavaScript. I will explain how you could assign a value from ADF Faces component to the plain HTML div.

The sample app is available on GitHub repo. It doesn't require DB connection, you can run it straight away in Oracle JDeveloper.

Look into JSF page. I have implemented ADF Faces input component with value change listener. Below this component, there is HTML div with ID (more...)

Cat or Dog — Image Classification with Convolutional Neural Network

The goal of this post is to show how convnet (CNN — Convolutional Neural Network) works. I will be using classical cat/dog classification example described in François Chollet book — Deep Learning with Python. Source code for this example is available on François Chollet GitHub. I’m using this source code to run my experiment.

Convnet works by abstracting image features from the detail to higher level elements. An analogy can be described with the way how humans think. (more...)

Run Oracle VBCS Application on Your Own Server

Latest VBCS release brings an option to export VBCS application and run on your own server (or different cloud provider). This is a truly strong step forward for VCBS. Read more about it in Shay Shmeltzer blog post. If you decide to keep running VBCS app within VBCS itself, then you get additional functionality of VBCS Business Services, Oracle Cloud security, etc. out of the box. If you export VBCS application and run on your (more...)

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...)

Publishing Machine Learning API with Python Flask

Flask is fun and easy to setup, as it says on Flask website. And that's true. This microframework for Python offers a powerful way of annotating Python function with REST endpoint. I’m using Flask to publish ML model API to be accessible by the 3rd party business applications.

This example is based on XGBoost.

For better code maintenance, I would recommend using a separate Jupyter notebook where ML model API will be published. Import Flask (more...)

Selecting Optimal Parameters for XGBoost Model Training

There is always a bit of luck involved when selecting parameters for Machine Learning model training. Lately, I work with gradient boosted trees and XGBoost in particular. We are using XGBoost in the enterprise to automate repetitive human tasks. While training ML models with XGBoost, I created a pattern to choose parameters, which helps me to build new models quicker. I will share it in this post, hopefully you will find it useful too.

I’m (more...)

Prepare Your Data for Machine Learning Training

The process to prepare data for Machine Learning model training to me looks somewhat similar to the process of preparing food ingredients to cook dinner. You know in both cases it takes time, but then you are rewarded with tasty dinner or a great ML model.

I will not be diving here into data science subject and discussing how to structure and transform data. It all depends on the use case and there are so (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...)

Intercepting ADF Table Column Show/Hide Event with Custom Change Manager Class

Ever wondered how to intercept ADF table column show/hide event from ADF Panel Collection component? Yes, you could use ADF MDS functionality to store user preference for table visible columns. But what if you would want to implement it yourself without using MDS? Actually, this is possible through custom persistence manager class. I will show you how.

If you don't know what I'm talking about. Check below screenshot, this popup comes out of the box (more...)

ADF Performance Improvement with Nginx Compression

We are using Nginx web server for Oracle ADF WorkBetter hosted demo hosted on DigitalOcean cloud server. Nginx helps to serve web application content fast and offer improved performance. One of the important tuning options - content compression, Nginx does this job well and is simple to setup.

Content compression doesn't provide direct runtime performance, a browser would run the same code, doesn't matter it was compressed or not. But it brings improved perceived performance (which (more...)