Installing the REST Process
The following steps will help you install the REST Process (REST).
Overview
The files needed for the REST process are the same as the files provided for JWP in the same directory as all the other Automation Engine files.
Since the installation of the JWP is mandatory and the files necessary for the REST process are the same as those used to install the JWP, there is no need to unpack any files nor to carry out any other installation step.
Notes:
- The installation of the REST process is relevant for the AE REST API as well as for the advanced object search. Make sure to configure the [REST] section of the Automation Engine configuration file (ucsrv.ini, see Automation Engine) accordingly.
- The Automation Engine uses TLS/SSL to secure and encrypt the communication. Make sure to create the respective keystore beforehand using pkcs 12 format and to configure the [TLS] section of the Automation Engine configuration file (ucsrv.ini, see Automation Engine) accordingly. For more information, see Securing Connections to the AE (TLS/SSL).
- If no REST process is available at login, the login fails and an error message is displayed. The system also notifies you if, for any reason, the minimum number of processes is not fulfilled during a session. The notification disappears once the process is running again.
- When the REST processes is initiated, it binds to the port you have defined in the JCP.PORTS parameter in the [PORTS] section of the AE INI file. If there is no port defined in this section, it binds randomly to another port, which is necessary for the internal communication between WP and REST process. When the REST process starts, it opens a random port and sends it internally via the database to the WPs so that WPs can reach the REST process. For more information ,see Configuring Firewall and Ports.
Starting the REST Process
Use this kind of command to start the REST process via the command line:
java -Xmx2G -jar ucsrvjp.jar -Iucsrv.ini -rest
The file "ucsrvjp.jar" is provided in the same directory as the other Automation Engine files. It is used exclusively to start the JWP and the REST process.
The REST process can also be started via ServiceManager.
java -Xmx2G -jar ucsrvjp.jar -Iucsrv.ini -svc%port% -rest
The -svc parameter should be omitted when starting directly via the command line.
The parameter -I to specify the INI file is optional. If the parameter is missing, the REST process attempts to find the file ucsrv.ini in the current working directory (same directory in which the file ucsrvjp.jar is located).
Setting Up Multiple REST API Processes
The REST process installation is relevant for the AE REST API and for the advanced object search. You can install a single REST process (REST). In this case, all REST requests are sent to this single AE REST API instance and no REST API is available if the REST process is down.
You can also set up a system with multiple REST processes. In this case, two REST processes are used in a cluster but only one of them is available at the time.
It is recommended using one REST process per node. However, you can also set up a system with multiple REST processes, which can be convenient for load balancing capabilities and to provide failover capabilities, because the REST requests are sent and distributed only to available REST processes. For more information, see AE REST API - General Info.
Important!
-
When setting up a system with multiple REST processes, it is imperative that each one uses its own Automation Engine configuration file (ucsrv.ini, see Automation Engine) and that different ports are assigned for each REST process. Otherwise, the first one connects successfully while the others terminated upon trying to register the same REST port if both run on the same node. An error message is written to the log file of the REST process stating the reason for termination.
-
If no REST process is available at login, the login fails and an error message is displayed. The system also notifies you if, for any reason, the minimum number of processes is not fulfilled during a session. The notification disappears once the process is running again.
Next step: