Code Structure

An exploration of the POB open-source code base.

Last Updated: 27 May 2022 • Page Author: Jillur Quddus

Overview

This page is intended for software engineers who wish to gain a better understanding of the structure of the POB open-source code base.

Prerequisites

Please ensure that you have read and followed the instructions in the Build from Source and Development Environment articles respectively prior to reading this page.

Software Services

The POB open-source code base can be broadly divided into the following categories.

Configuration

The following Maven modules are relative to $POB_BASE.

Maven Module	Logical Software Service	Description
pob-configuration	Global configuration	This Maven module contains the global configuration for POB's Spring bootstrap and application contexts respectively, and is included as a dependency in all of POB's applications.

Entity Model

The following Maven modules are relative to $POB_BASE.

Maven Module	Logical Software Service	Description
pob-model	Entity Model	This Maven module contains the POB entity model (for example the framework, opportunity and publisher class definitions), and is included as a dependency in all of POB's applications.

Core Services

The following Maven modules are relative to $POB_BASE/pob-core.

Maven Module	Logical Software Service	Description
pob-io	IO services	This Maven module contains POB's services for processing YAML files and mapping Java objects to JSON.
pob-jpa	RDBMS data services	This Maven module contains POB's Spring Data JPA entity repositories (for example managing the persistence and querying of framework and opportunity objects in relevant SQL tables).
pob-utils	Utility services	This Maven module contains POB's utility methods, including utility methods for date formatting and hashing.

Data Services

The following Maven modules are relative to $POB_BASE/pob-data.

Maven Module	Logical Software Service	Description
pob-parsers	Native procurement framework parsers	This Maven module contains POB's native procurement framework parsers.
pob-pipelines	Native end-to-end data pipelines	This Maven module contains POB's main end-to-end data pipeline responsible for executing all the registered parsers and publishers listed and enabled in the POB Application Configuration.
pob-publishers	Native opportunity publishers to downstream applications	This Maven module contains POB's native opportunity publishers to downstream applications such as Slack, Microsoft Teams and Google Chat.

Application Wrappers

The following Maven modules are relative to $POB_BASE/pob-apps.

Maven Module	Logical Software Service	Description
pob-apps-spring	Spring Boot applications	This Maven module contains POB's Spring Boot applications that are designed for deployment to self-managed or Spring Cloud environments.
pob-apps-aws	AWS Spring Boot applications	This Maven module contains POB's Spring Boot applications that are designed for deployment to AWS Lambda functions.
pob-apps-azure	Azure Spring Boot applications	This Maven module contains POB's Spring Boot applications that are designed for deployment to Azure Function apps.

Parent POM

The POB parent POM, found at $POB_BASE/pom.xml, contains the exhaustive list of all 3rd party Java dependencies directly utilised by the POB open-source project along with their version numbers. All the POB Maven modules listed above are children (or grandchildren) of the parent POM and thus inherit all configuration defined in it.

Parent Maven Profiles

In addition to dependency management, the POB parent POM also defines the following Maven profiles that can be selected based on which services you wish to build and package:

Profile Name	Default Profile	Description
apps	Yes	Manages the lifecycle of all of POB's core services as well as all POB Spring Boot applications across all cloud vendors.

Maven Application Profiles

In addition to the Maven profiles defined in the POB parent POM, four (4) further Maven application-specific profiles are defined in $POB_BASE/pob-apps/pom.xml. These Maven profiles enable software and platform engineers to explicitly select which Spring Boot applications to compile, build and package based on the target deployment environment, as follows:

Profile Name	Default Profile	Description
apps-multicloud	Yes	Manages the lifecycle of all POB Spring Boot applications (i.e. serverless function apps and API applications) across all cloud vendors.
apps-spring	No	Manages the lifecycle of Spring Boot applications designed for development and testing purposes, or for deployment to self-managed or Spring Cloud environments.
apps-aws	No	Manages the lifecycle of AWS Spring Boot applications designed for deployment to AWS Lambda and AWS Beanstalk apps respectively.
apps-azure	No	Manages the lifecycle of Microsoft Azure Spring Boot applications designed for deployment to Azure Function apps and Azure Web Apps respectively.