ORDS (Oracle REST Data Services)

What is Oracle Rest Data Services (ORDS)?

Oracle Rest Data Services (ORDS) allows you to publish a REST API for your information in the database. ORDS simplifies developing a REST interface/service for relative information. This comparative information is often held on either Associate in Nursing Oracle information, Associate in Nursing Oracle 12c JSON Document Store, or Associate in Nursing Oracle NoSQL information.

ORDS could be a java-based utility employed to wrap your information DML operative with web-service like GET, PUT, POST, etc., and result in a JSON format.

Use Case

The primary use case is to expose existing data as a REST service. Data typically resides in a database, and with the help of ORDS, we can disclose data with secure REST API.

REST API can be consumed in applications, integrations, or any third-party tool which allows REST API calls.

The Audience:

Recommended users are those who have a technical background in REST service. This document will help organizations/users who need to install ORDS on their VM

Download ORDS

Download the file ords.zip from the Oracle REST Data Services page.

https://www.oracle.com/database/technologies/appdev/rest-data-services-downloads.html

Installation

Deploy Oracle REST Data Services. Deployment options include:

• Standalone Mode
• Oracle WebLogic Server
• GlassFish Server
• Apache Tomcat

This section describes how to run Oracle REST Data Services in standalone mode.

Standalone mode is suitable for designing web-service base functionality, and we can consume these services in VBCS, OIC, or third-party applications.

You can install ORDS into one or more pluggable databases PDBs in a multitenant database or the container database (CDB). The installation choices are as follows:

• If you want the same ORDS version available in all the PDBs, then install it into the CDB. Instructions are used in this topic to be installing into CDB.
• If you want only some PDBs to use ORDS, or if you wish to different PDBs to use different versions of ORDS, then install them into the desired PDBs.
• The below command is used to verify multitenant instances.

SELECT name, cdb, con_id FROM v$database;

The CDB column will contain a 'Y' if the instance is multitenant. There is an option to install APEX in the CDB or as a standalone install for PDB. The following query lists the PDBs in a multitenant instance:

select name, open_mode, restricted from v$pdbs;

In general, the standalone APEX installation for the PDB is recommended.

Installation commands:

Download Oracle REST Data Services (ORDS) file from - ords-20.2.1.227.0350.zip

https://www.oracle.com/database/technologies/appdev/rest-data-services-downloads.html

Copy ords-20.2.1.227.0350.zip to /home/opc.

Connect with the OPC user to your VM.

Installing a Trusted SSL Certificate

https://blogs.oracle.com/dbcs/installing-a-trusted-ssl-certificate-on-oracle-database-cloud-service-for-apex

or

You can generate a certificate with your own- or a third-party tool. Oracle recommends Comodo.

Move cert and key to the /home/opc path and edit the. properties file.

Secure port registration

• Register port in OIC console – Add ingress rule for your port > in OIC console.

  Network – VCN Cloud Networks – click on Subnet and add ingress rule.

  

• Register your port at the OS level.

  Connect to the VM with OPC and register your port.

  Sudo -i
  To list the existing rules run:

  # iptables -L INPUT -n --line-number

  To add the rule at the end of the list, it should be added before the last "REJECT" line:

  # iptables -I INPUT 12 -m state --state NEW -m tcp -p tcp --dport >-j ACCEPT

  To save the configuration to make it permanent so it gets automatically applied after reboot, run:

  # service iptables save

  Reboot the system (optional)

Authorization

To protect the web service from the outside world, we need to create a role with an associated privilege and then map the privilege to the web service. Typically, we would expect a position to be a collection of privileges and permissions; of course, a single privilege can be part of multiple roles.

Example:

Connect to ORDS enabled schema with PDB service.

Create Role:

Define privilege

Authentication user creation

Go to the ORDS directory and execute the below command

$JAVA_HOME/bin/java -jar ords.war user <<user_name>> <<role_name>>

User information gets stored in the credential file.

Example:

Useful Commands

Summary:

Standalone ORDS is useful to expose PL/SQL APIs, and a Custom table using RESTfull web services. This would be particularly useful when creating an integration/VBCS application with REST API and want to get data in the desired pattern.