Description files in the echo example
Description of the Client entity
The Client entity does not implement an interface, so all you need to do is declare the entity name in its EDL description:
Client.edl
/* Description of the Client entity. */
entity echo.Client
Server entity description
The description of the Server entity must contain information stating that it implements the Ping interface. Using static descriptions, you need to insert the implementation of the Ping interface into the new component (for example, Ping) and insert the instance of this component into the Server entity.
The Server entity contains an instance of the Ping component:
Server.edl
/* Description of the Server entity. */
entity echo.Server
/* Server is a named instance of the echo.Ping component. */
components {
Server: echo.Ping
}
The Ping component contains the implementation of the Ping interface:
Ping.cdl
/* Description of the Ping component. */
component echo.Ping
/* ping is the Ping interface implementation. */
interfaces {
ping: echo.Ping
}
The Ping package contains a declaration of the Ping interface:
Ping.idl
/* Description of the Ping package. */
package echo.Ping
interface {
Ping(in UInt32 value, out UInt32 result);
}
Init description
To enable the Client entity to call a method of the Server entity, a connection (IPC channel) must be created between them.
To do so, in the init description indicate that the Client and Server entities must be started and connect them:
init.yaml
entities:
- name: echo.Client
connections:
- target: echo.Server
id: server_connection
- name: Server
The Server entity is indicated as - target, so it will perform the server entity role, meaning it will accept requests from the Client entity and respond to them.
The created IPC channel is named server_connection. You can obtain the handle of this channel by using the Service Locator.