6.12.1 Prerequisites

Before you begin, complete the following tasks.

• Create or identify a working stack comprising of Oracle REST Data Services (ORDS), Oracle APEX, and Oracle Database. This stack can run in the same Kubernetes cluster in which MicroTx runs or it can run in any other environment.
• Ensure that there is network access or connectivity between MicroTx and the database application if you have not deployed them in the same Kubernetes cluster.
• Use an existing schema or create a new schema in Oracle Database. Ensure that you register the schema with ORDS. See How to Access RESTful Services in Oracle® Application Express SQL Workshop Guide.
• Ensure that the ORDS service is available for the schema you have registered. For example, http://localhost:50080/ords.
• Log in to your SQL Developer Web interface using the admin or sysdba user credentials. To enable SQL Developer Web, see Enabling User Access to SQL Developer Web in Using Oracle® SQL Developer Web.
• Grant connect privileges to the APEX database user. See Granting Connect Privileges in Oracle® APEX Installation Guide.

• Add permissions by creating an access control list (ACL) if outbound REST calls are not allowed by default.

  The MicroTx library makes an outbound REST call to the MicroTx transaction coordinator for enlisting the participant service into an XA transaction.

  Create the required ACL, configure it, and then add it to the database. You will need sysdba permissions to add an ACL. The following example shows a sample ACL which is used only in restricted environments, such as production environments. For more information about adding an ACL, see the APEX documentation.

  /
  BEGIN
  DBMS_NETWORK_ACL_ADMIN.APPEND_HOST_ACE(
  host => '#TMM_HOST_NAME',
  lower_port => null,
  upper_port => null,
  ace => xs$ace_type(privilege_list => xs$name_list('connect', 'resolve', 'http'),
  principal_name => '#PRINCIPAL_NAME',
  principal_type => xs_acl.ptype_db));
  END;
  /

  Where, you must replace the following values with values that are specific to your environment.

  • #TMM_HOST_NAME: Enter the host name or the external IP address of MicroTx.
  • #PRINCIPAL_NAME: Enter the name of the principal user of APEX.