Add python module (python wrapper for libcppl)

Author: jenshiller

Makefile

@@ -68,6 +68,10 @@ performance.o: performance.c performance.h
 policy-decision-point:
 	$(MAKE) -C policy-decision-point
 
+.PHONY: python-module
+python-module:
+	$(MAKE) -C python-module
+
 test:
 	make -C examples/test_cases/
 	make -C examples/test_cases/ clean
@@ -81,3 +85,4 @@ clean:
 	#delete output from reason printer
 	$(RM) *.json
 	$(MAKE) clean -C policy-decision-point
+	$(MAKE) clean -C python-module

README.md

@@ -26,6 +26,15 @@ make
 make test
 ```
 
+#### Integrating CPPL in your python project
+
+If you want to use CPPL from a python project you may use the available python module, which is built with
+```bash
+make python-module
+```
+This will produce `cppl_cpp_python_bridge.so` and `cppl.py` in `python-module/build/lib.<architecture>`.
+You should only use `cppl.py` in your python project, but still need to make `cppl_cpp_python_bridge.so` and `policy-decision-point/libcppl.so` available for the python interpreter, e.g., by setting `LD_LIBRARY_PATH` accordingly.
+
 #### Troubeshooting
 
 If your system provides the jsoncpp library in version smaller 0.7.0 the compiling process will encounter errors such as ```undefined reference to `Json::Value::isInt64() const'```. In such a case, please set `USE_SYSTEM_JSONCPP` in Makefile and policy-decision-point/Makefile to 0 to use the jsoncpp version included in this repository.

python-module/.gitignore

@@ -0,0 +1,3 @@
+build
+cppl.so
+

python-module/Makefile

@@ -0,0 +1,29 @@
+
+SOURCES = cpplmodule.cc cppl.py
+OBJFILES = 
+
+MODULES =
+
+cppl.so: build
+
+# TODO clean dependency ensures that always the newest ../../libprivercloud.a is used
+build: clean setup.py $(SOURCES) $(OBJFILES) $(MODULES) libcppl
+	python setup.py build
+
+sdist: $(SOURCES) setup.py $(OBJFILES) libcppl
+	@echo "WARNING: untested makefile target"
+	python setup.py sdist
+
+install: $(SOURCES) setup.py $(OBJFILES) libcppl
+	@echo "WARNING: untested makefile target"
+	python setup.py install
+
+.PHONY: libcppl
+libcppl:
+	make -C ../policy-decision-point/ lib
+
+tidy:
+	rm -fr build
+
+clean: tidy
+

python-module/cppl.py

@@ -0,0 +1,87 @@
+import cppl_cpp_python_bridge as cppl_bridge
+
+error = cppl_bridge.error
+
+def init():
+    cppl_bridge.init()
+
+def cleanup():
+    cppl_bridge.cleanup()
+
+class PolicyDefinition(object):
+    """docstring for PolicyDefinition"""
+    def __init__(self, policyDefinitionPath, functionHandlerPath):
+        super(PolicyDefinition, self).__init__()
+        self.pd_id = cppl_bridge.read_policy_definition_from_file( policyDefinitionPath, functionHandlerPath)
+
+    def get_id(self):
+        return self.pd_id
+
+    def __del__(self):
+        cppl_bridge.policy_definition_free( self.get_id() )
+
+class NodeParameters(object):
+    """docstring for NodeParameters"""
+    def __init__(self, nodeParametersPath, nodeRuntimeParametersPath, policyDefinition):
+        # sanity checks
+        if type(policyDefinition) != PolicyDefinition:
+            raise TypeError
+
+        super(NodeParameters, self).__init__()
+        self.np_id = cppl_bridge.read_node_parameters_from_file( nodeParametersPath, nodeRuntimeParametersPath, policyDefinition.get_id() )
+
+    def get_id(self):
+        return self.np_id
+
+    def __del__(self):
+        cppl_bridge.node_parameters_free( self.get_id() )
+
+class Policy(object):
+    """docstring for Policy"""
+    def __init__(self, policyPath):
+        super(Policy, self).__init__()
+        self.string = cppl_bridge.read_policy_from_file( policyPath )
+
+    def get_string(self):
+        return self.string
+
+    def compress_to_file(self, destPath, policyDefinition):
+        # sanity checks
+        if type(policyDefinition) != PolicyDefinition:
+            raise TypeError
+
+        ret = cppl_bridge.compress_policy_to_file(self.get_string(), policyDefinition.get_id(), destPath)
+
+    # def __del__(self):
+    #     # Nothing todo as only a string is passed from C++ to Python
+    #     cppl_bridge.compressed_cppl_free( self.get_id() )
+
+class CompressedPolicy(object):
+    """docstring for CompressedPolicy"""
+    def __init__(self, compressedPolicyPath, policyDefinition):
+        # sanity checks
+        if type(policyDefinition) != PolicyDefinition:
+            raise TypeError
+
+        super(CompressedPolicy, self).__init__()
+        self.ccppl_id = cppl_bridge.read_compressed_cppl_from_file( compressedPolicyPath, policyDefinition.get_id() )
+        self.policyDefinition = policyDefinition
+
+    def get_id(self):
+        return self.ccppl_id
+
+    def __del__(self):
+        cppl_bridge.compressed_cppl_free( self.get_id() )
+
+    def evaluate(self, nodeParameters, with_reason=True):
+        # sanity checks
+        if type( nodeParameters ) != NodeParameters:
+            raise TypeError
+
+        ret_eval = cppl_bridge.evaluate(self.get_id(), nodeParameters.get_id() )
+
+        reason = None
+        if with_reason:
+            reason = cppl_bridge.get_reason( self.get_id(), self.policyDefinition.get_id() )
+
+        return ret_eval, reason