One way to demonstrate this distribution provider is to have a Java-based OSGi Remote Service and call/use/consume it from a Python process or a Java process. Just to be clear, with these same components (based upon OSGi Remote Services and Remote Service Admin specifications) it is completely possible to export a Python-implemented service, and consume the service from either a Java or Python process as well. For simplification, the example below exports a remote service from Java, and imports/uses/consumes that service from Python.
This example HelloImpl.java from this repository shows a small OSGi Async Remote Service with three service methods.
To install and start this example service in Karaf 4.4.6 paste or type the following into the karaf console:
karaf@root()> feature:repo-add https://download.eclipse.org/rt/ecf/latest/karaf-features.xml karaf@root()> feature:install ecf-rs-examples-python.java-hello
After installing all OSGi and ECF components, and exporting the HelloImpl service, the Karaf console will print out the OSGi standard export registration and endpoint desription
19:20:03.679;EXPORT_REGISTRATION;exportedSR=[org.eclipse.ecf.examples.hello.IHello];cID=URIID [uri=py4j://127.0.0.1:25333/java];rsId=1
--Endpoint Description---
<endpoint-descriptions xmlns="http://www.osgi.org/xmlns/rsa/v1.0.0">
<endpoint-description<
<property name="ecf.endpoint.id" value-type="String" value="py4j://127.0.0.1:25333/java"/>
...continues with the entire endpoint description
The py4j://127.0.0.1:25333/java as the value for ecf.endpoint.id property indicates that a listener has been opened on 127.0.0.1 (localhost) using port 25333 and waiting for connections from clients.
To run the example python client program it's necessary to first install the osgiservicebridge python library (part of this codebase in python/osgiservicebridge
Osgiservicebridge Install
Install via Pip/Pypi (currently version 1.5.7)
pip install osgiservicebridge
OR install via repo by going to the python/osgiservicebridge directory and running setup.py as follows
python setup.py install develop
The python hello service client can then be run by going to the examples/org.eclipse.ecf.examples.hello.pythonclient/src directory and starting the run.py example program.
python run.py
After starting run.py, on the Karaf/Java side you should see console output like this
Java.sayHello called by from.python with message: 'this is a big hello from Python!!!'
and on the Python side there should be console output like this
bridge created
service_imported endpointid=02ea388d-417d-48ce-8372-ed9ed0714bb4;proxy=org.eclipse.ecf.examples.hello.javahost.HelloImpl@59f0e37d;endpoint_props={'objectClass':
...more endpoint description contents
response=Java says: Hi from.python, nice to see you
bridge connected
service_unimported endpointid=02ea388d-417d-48ce-8372-ed9ed0714bb4;proxy=org.eclipse.ecf.examples.hello.javahost.HelloImpl@59f0e37d;endpoint_props={'objectClass':
...more endpoint description contents
disconnected...exiting
This codebase to use Google Protocol Buffers for high-performance serialization/deserialization, as well as support for client, server, and/or bidirectional streaming and gRPC.
For support please open an issue on this repo, or contact scottslewis@gmail.com
The OSGi Service Bridge Python source code is in the python/osgiservicebridge project. This package should be installed into Python 3.3+ prior to running the pythonclient example.
Python Impl of OSGi Bundle, Service, and Remote Service Admin in iPopo v3
A full Python implementation of OSGi bundle and service layer, along with Remote Services and Remote Service Admin implementations in python is also available via the iPopo v3 project. Note that this python based implementation of Remote Services and Remote Service Admin is makes Python and Java-based remote services completely interoperable, and allows the use of multi-language service discovery systems like etcd3 (discovery protocol for Kubernetes) and multi-language distribution systems such as grpc.
Python.Java Remote Services is distributed with the Apache2 license. See LICENSE in this directory for more information.