support local config and policy files

* DCAEGEN2-2733/DCAEGEN2-2753 - onap-dcae-cbs-docker-client support local config and policy files
	Support $CBS_CLIENT_CONFIG_PATH and $CBS_CLIENT_POLICY_PATH,
	Default paths are /app-config/application_config.yaml and /etc/policies/policies.json.
	If files are missing or malformed, drop back to the current behavior.

Change-Id: Iba2484f6be7fc54e412f7de302bb79a4d7bfde17
Signed-off-by: Hansen, Tony (th1395) <th1395@att.com>
Issue-ID: DCAEGEN2-2733
Issue-ID: DCAEGEN2-2753
Signed-off-by: Hansen, Tony (th1395) <th1395@att.com>

9 files changed, 470 insertions, 43 deletions

diff --git a/onap-dcae-cbs-docker-client/Changelog.md b/onap-dcae-cbs-docker-client/Changelog.md
index c16950d..c70aff4 100644
--- a/onap-dcae-cbs-docker-client/Changelog.md
+++ b/onap-dcae-cbs-docker-client/Changelog.md
@@ -4,16 +4,22 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## [2.1.2] - 05/13/2021 
+## [2.2.0] 2021/06/22
+* DCAEGEN2-2733/DCAEGEN2-2753 - onap-dcae-cbs-docker-client support local config and policy files
+	Support $CBS_CLIENT_CONFIG_PATH and $CBS_CLIENT_POLICY_PATH,
+	Default paths are /app-config/application_config.yaml and /etc/policies/policies.json.
+	If files are missing or malformed, drop back to the current behavior.
+
+## [2.1.2] - 2021/05/13
 * Add service for envs present in configuration
 
-## [2.1.1] - 04/27/2020
+## [2.1.1] - 2020/04/27
 * Bug fix DCAEGEN2-2213 ConnectionError exception is lost when CBSUnreachable is raised
 
-## [2.1.0] - 6/24/2019
+## [2.1.0] - 2019/6/24
 * Add support for connecting to the CBS if it is running as HTTPS instead of HTTP
 
-## [2.0.0] - 6/19/2019
+## [2.0.0] - 2019/6/19
 * The env variable CONFIG_BINDING_SERVICE now has a different meaning per DCAEGEN2-1537. Specifically this variable now holds a resolvable hostname for the CBS, rather than a consul lookup key
 * Since the API was broken anyway, the decision not to throw an exception was revisted and overturned. This was causing problems for some users, who were getting `{}` back in their configuration, but without knowing why; either the config wasn't set up, the config was set but as `{}`, or the CBS being unreachable altogether. This client library now throws native python exceptions, rather than logging and returning `{}`. The application client code can handle the exceptions, and retry if they choose.
 * Add more tests, move fixtures to conftest
diff --git a/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/client.py b/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/client.py
index 7f36169..c42b4ae 100644
--- a/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/client.py
+++ b/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/client.py
@@ -1,5 +1,5 @@
 # ================================================================================
-# Copyright (c) 2017-2019 AT&T Intellectual Property. All rights reserved.
+# Copyright (c) 2017-2021 AT&T Intellectual Property. All rights reserved.
 # Copyright (C) 2021 Nokia. All rights reserved.
 # ================================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -14,18 +14,36 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ============LICENSE_END=========================================================
-#
-# ECOMP is a trademark and service mark of AT&T Intellectual Property.
+
+""" provide a means to return a configuration to CBS """
 
 import json
 import os
 import requests
+import sys
+import yaml
+
 from onap_dcae_cbs_docker_client import get_module_logger
 from onap_dcae_cbs_docker_client.exceptions import ENVsMissing, CantGetConfig, CBSUnreachable
 
 logger = get_module_logger(__name__)
 
 
+DEFAULT_CONFIG_PATH = "/app-config/application_config.yaml"
+DEFAULT_POLICY_PATH = "/etc/policies/policies.json"
+
+
+# provide a means to import the default paths into unit tests
+# For some reason, tox does not like
+# from onap_dcae_cbs_docker_client.client import DEFAULT_CONFIG_PATH, DEFAULT_POLICY_PATH
+
+def default_config_path():
+    return DEFAULT_CONFIG_PATH
+
+
+def default_policy_path():
+    return DEFAULT_POLICY_PATH
+
 #########
 # HELPERS
 
@@ -35,7 +53,7 @@ def _recurse(config):
     Recurse through a configuration, or recursively a sub element of it.
     If it's a dict: recurse over all the values
     If it's a list: recurse over all the values
-    If it's a string: return the replacement
+    If it's a string: expand the string and return its replacement
     If none of the above, just return the item.
     """
     if isinstance(config, list):
@@ -96,11 +114,13 @@ def change_envs(value):
     """
     Replace env reference by actual value and return it
     """
-    if value.startswith('$'):
-        try:
-            value = os.environ[value.replace('${', '').replace('}', '')]
-        except KeyError as e:
-            raise ENVsMissing("Required ENV Variable {0} missing".format(e))
+    if value.startswith('${'):
+        name = value[2:-1]
+        if name in os.environ:
+            return os.environ[name]
+
+        logger.error(f"Required ENV Variable '{name}' missing. Is '{value}' properly formatted?")
+        raise ENVsMissing(f"Required ENV Variable {name} missing. Is '{value}' properly formatted?")
     return value
 
 
@@ -108,18 +128,113 @@ def change_envs(value):
 # Public
 def get_all():
     """
-    Hit the CBS service_component_all endpoint
+    If not configured locally,
+    hit the CBS service_component_all endpoint
+
+    Local configuration comes from $CBS_CLIENT_CONFIG_PATH and $CBS_CLIENT_POLICY_PATH,
+    defaulted to /app-config/application_config.yaml and /etc/policies/policies.json.
     """
+    config_path = os.getenv("CBS_CLIENT_CONFIG_PATH", DEFAULT_CONFIG_PATH)
+    if config_path == "":
+        config_path = DEFAULT_CONFIG_PATH
+    policy_path = os.getenv("CBS_CLIENT_POLICY_PATH", DEFAULT_POLICY_PATH)
+    if policy_path == "":
+        policy_path = DEFAULT_POLICY_PATH
+
+    try:
+        logger.debug(f"opening config_path={config_path}")
+        with open(config_path) as fp:
+            config = yaml.safe_load(fp)
+
+        policies = None
+        try:
+            logger.debug(f"opening policy_path={policy_path}")
+            with open(policy_path) as fp:
+                policies = json.load(fp)
+
+        except FileNotFoundError:
+            logger.debug("Policy File Not Found exception received")
+            pass
+
+        except (json.decoder.JSONDecodeError, ValueError) as e:
+            logger.error(f"The policy file '{policy_path}' has invalid JSON: %s", e)
+            pass
+
+        except Exception as e:
+            logger.error(f"An error occurred processing the policy file '{policy_path}': %s", e)
+            import traceback
+            traceback.print_exc(file=sys.stderr)
+            pass
+
+        if policies is not None:
+            if "policies" in policies:
+                logger.debug(f"Returning config read from {config_path} an policy read from {policy_path}")
+                ret = {"config": _recurse(config), "policies": policies["policies"]}
+            else:
+                logger.error(f"The policy file '{policy_path}' does NOT have a 'policies' block in it.")
+                ret = {"config": _recurse(config)}
+        else:
+            logger.debug(f"Returning config read from {config_path}")
+            ret = {"config": _recurse(config)}
+
+        return ret
+
+    except yaml.scanner.ScannerError as e:
+        logger.error(f"The configuration file '{config_path}' has invalid YAML: {e}")
+        pass
+
+    except FileNotFoundError:
+        logger.debug("Config File Not Found exception received")
+        pass
+
+    except Exception as e:
+        logger.error(f"An error occurred processing the configuration file '{config_path}': {e}")
+        import traceback
+        traceback.print_exc(file=sys.stderr)
+        pass
+
+    logger.debug("Fallback to using REST call")
     config = _get_path("service_component_all")
     return _recurse(config)
 
 
 def get_config():
     """
-    Hit the CBS service_component endpoint
+    If not configured locally,
+    hit the CBS service_component endpoint for the configuration.
+
+    Local configuration comes from $CBS_CLIENT_CONFIG_PATH,
+    defaulted to /app-config/application_config.yaml.
 
     TODO: should we take in a "retry" boolean, and retry on behalf of the caller?
     Currently, we return an exception and let the application decide how it wants to proceed (Crash, try again, etc).
     """
+    config_path = os.getenv("CBS_CLIENT_CONFIG_PATH", DEFAULT_CONFIG_PATH)
+    if config_path == "":
+        config_path = DEFAULT_CONFIG_PATH
+
+    try:
+        logger.debug(f"opening config_path={config_path}")
+        with open(config_path) as fp:
+            config = yaml.safe_load(fp)
+
+        logger.debug(f"Returning config read from {config_path}")
+        return _recurse({"config": config})
+
+    except yaml.scanner.ScannerError as e:
+        logger.error(f"The configuration file '{config_path}' has invalid YAML: {e}")
+        pass
+
+    except FileNotFoundError:
+        logger.debug("Config File Not Found exception received")
+        pass
+
+    except Exception as e:
+        logger.error(f"An error occurred processing the configuration file '{config_path}': {e}")
+        import traceback
+        traceback.print_exc(file=sys.stderr)
+        pass
+
+    logger.debug("Fallback to using REST call")
     config = _get_path("service_component")
     return _recurse(config)
diff --git a/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/exceptions.py b/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/exceptions.py
index 6b73b91..0cd19fd 100644
--- a/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/exceptions.py
+++ b/onap-dcae-cbs-docker-client/onap_dcae_cbs_docker_client/exceptions.py
@@ -1,5 +1,5 @@
 # ================================================================================
-# Copyright (c) 2019 AT&T Intellectual Property. All rights reserved.
+# Copyright (c) 2019-2021 AT&T Intellectual Property. All rights reserved.
 # ================================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -13,8 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ============LICENSE_END=========================================================
-#
-# ECOMP is a trademark and service mark of AT&T Intellectual Property.
+
+""" exceptions used by the Config Binding Server """
 
 
 class ENVsMissing(Exception):
diff --git a/onap-dcae-cbs-docker-client/pom.xml b/onap-dcae-cbs-docker-client/pom.xml
index b566d89..4783ada 100644
--- a/onap-dcae-cbs-docker-client/pom.xml
+++ b/onap-dcae-cbs-docker-client/pom.xml
@@ -28,7 +28,7 @@ ECOMP is a trademark and service mark of AT&T Intellectual Property.
   <groupId>org.onap.dcaegen2.utils</groupId>
   <artifactId>onap-dcae-cbs-docker-client</artifactId>
   <name>dcaegen2-utils-python-cbs-docker-client</name>
-  <version>2.1.2-SNAPSHOT</version>
+  <version>2.2.0-SNAPSHOT</version>
   <url>http://maven.apache.org</url>
 
   <properties>
diff --git a/onap-dcae-cbs-docker-client/setup.py b/onap-dcae-cbs-docker-client/setup.py
index 84b7436..585d628 100644
--- a/onap-dcae-cbs-docker-client/setup.py
+++ b/onap-dcae-cbs-docker-client/setup.py
@@ -1,5 +1,5 @@
 # ================================================================================
-# Copyright (c) 2017-2019 AT&T Intellectual Property. All rights reserved.
+# Copyright (c) 2017-2021 AT&T Intellectual Property. All rights reserved.
 # Copyright (C) 2021 Nokia. All rights reserved.
 # ================================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -20,7 +20,7 @@ from setuptools import setup, find_packages
 setup(
     name="onap_dcae_cbs_docker_client",
     description="very lightweight client for a DCAE dockerized component to get it's config from the CBS",
-    version="2.1.2",
+    version="2.2.0",
     packages=find_packages(),
     author="Tommy Carpenter",
     author_email="tommy@research.att.com",
diff --git a/onap-dcae-cbs-docker-client/tests/conftest.py b/onap-dcae-cbs-docker-client/tests/conftest.py
index 0f34ff1..5dc877d 100644
--- a/onap-dcae-cbs-docker-client/tests/conftest.py
+++ b/onap-dcae-cbs-docker-client/tests/conftest.py
@@ -1,5 +1,5 @@
 # ================================================================================
-# Copyright (c) 2019 AT&T Intellectual Property. All rights reserved.
+# Copyright (c) 2019-2021 AT&T Intellectual Property. All rights reserved.
 # Copyright (C) 2021 Nokia. All rights reserved.
 # ================================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -14,8 +14,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ============LICENSE_END=========================================================
-#
-# ECOMP is a trademark and service mark of AT&T Intellectual Property.
+
+""" helper functions/classes for unit tests for Config Binding Server """
+
 import pytest
 from requests.exceptions import HTTPError, ConnectionError
 
diff --git a/onap-dcae-cbs-docker-client/tests/test_client.py b/onap-dcae-cbs-docker-client/tests/test_client.py
index 3b10923..76249d4 100644
--- a/onap-dcae-cbs-docker-client/tests/test_client.py
+++ b/onap-dcae-cbs-docker-client/tests/test_client.py
@@ -1,5 +1,5 @@
 # ================================================================================
-# Copyright (c) 2017-2019 AT&T Intellectual Property. All rights reserved.
+# Copyright (c) 2017-2021 AT&T Intellectual Property. All rights reserved.
 # Copyright (C) 2021 Nokia. All rights reserved.
 # ================================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -14,22 +14,37 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ============LICENSE_END=========================================================
+
+""" unit tests for Config Binding Server """
+
 import pytest
+import io
+import json
+import os
+import yaml
+
+from unittest.mock import patch
+
 from onap_dcae_cbs_docker_client.client import get_config, get_all
+from onap_dcae_cbs_docker_client.client import default_config_path, default_policy_path
 from onap_dcae_cbs_docker_client.exceptions import CantGetConfig, CBSUnreachable, ENVsMissing
 
 
+DEFAULT_REQUESTS_CONFIG = {"key_to_your_heart": 666}
+DEFAULT_REQUESTS_CONFIG_ALL = {
+    "config": {"key_to_your_heart": 666},
+    "dti": {"some amazing": "dti stuff"},
+    "policies": {"event": {"foo": "bar"}, "items": [{"foo2": "bar2"}]},
+    "otherkey": {"foo3": "bar3"},
+}
+
+
 def test_http(monkeypatch, monkeyed_requests_get):
     monkeypatch.setattr("requests.get", monkeyed_requests_get)
 
-    assert get_config() == {"key_to_your_heart": 666}
+    assert get_config() == DEFAULT_REQUESTS_CONFIG
 
-    assert get_all() == {
-        "config": {"key_to_your_heart": 666},
-        "dti": {"some amazing": "dti stuff"},
-        "policies": {"event": {"foo": "bar"}, "items": [{"foo2": "bar2"}]},
-        "otherkey": {"foo3": "bar3"},
-    }
+    assert get_all() == DEFAULT_REQUESTS_CONFIG_ALL
 
 
 def test_https_url(monkeypatch, monkeyed_requests_get_https):
@@ -113,3 +128,288 @@ def test_http_with_wrong_env(monkeypatch, monkeyed_requests_get_http_with_wrong_
         get_config()
     with pytest.raises(ENVsMissing):
         get_all()
+
+
+################
+################
+# Tests for using local configuration and profile files.
+################
+################
+
+# Combinations to test:
+# $CBS_CLIENT_CONFIG_PATH set, set to "", not set
+# $CBS_CLIENT_POLICY_PATH set, set to "", not set
+# config_path file exists, not exists
+# policy_path file exists, not exists
+# good config, bad config
+# good policy, bad policy
+# call get_all(), get_config()
+# config has ${VAR} to be expanded
+# policy does NOT expand ${VAR}
+
+# JSON found in https://jira.onap.org/browse/DCAEGEN2-2753
+policy_default = ''.join(['{"policies": {"items": [{"type": "onap.policies.monitoring.tcagen2", ',
+                          '"type_version": "1.0.0", "name": "onap.vfirewall.tca", "version": "1.0.0", ',
+                          '"metadata": {"policy-id": "onap.vfirewall.tca", "policy-version": "1.0.0"}, ',
+                          '"policyName": "onap.vfirewall.tca.1-0-0.xml", "policyVersion": "1.0.0", ',
+                          '"config": {"tca.policy": {"domain": "measurementsForVfScaling", ',
+                          '"metricsPerEventName": [{"eventName": "vFirewallBroadcastPackets", ',
+                          '"controlLoopSchemaType": "VM", "policyScope": "DCAE", "policyName": ',
+                          '"DCAE.Config_tca-hi-lo", "policyVersion": "v0.0.1", "thresholds": ',
+                          '[{"closedLoopControlName": ',
+                          '"ControlLoop-vFirewall-d0a1dfc6-94f5-4fd4-a5b5-4630b438850a", ',
+                          '"version": "1.0.2", "fieldPath": ',
+                          '"$.event.measurementsForVfScalingFields.vNicPerformanceArray[*].',
+                          'receivedTotalPacketsDelta", "thresholdValue": 300, "direction": ',
+                          '"LESS_OR_EQUAL", "severity": "MAJOR", "closedLoopEventStatus": ',
+                          '"ONSET"}, {"closedLoopControlName": "ControlLoop-vFirewall-d0a1dfc6-',
+                          '94f5-4fd4-a5b5-4630b438850a", "version": "1.0.2", "fieldPath": ',
+                          '"$.event.measurementsForVfScalingFields.vNicPerformanceArray[*].',
+                          'receivedTotalPacketsDelta", "thresholdValue": 700, "direction": ',
+                          '"GREATER_OR_EQUAL", "severity": "CRITICAL", "closedLoopEventStatus": ',
+                          '"ONSET"}]}]}}}]}, "event": {"action": "gathered", "timestamp": ',
+                          '"2021-04-19T23:37:19.709Z", "update_id": "379fb01a-cfe2-4c06-8f6b-',
+                          'd51f3c8504af", "policies_count": 1}}'])
+found_policy_path = '{"policies": "found policy/path"}'
+found_policy_path_with_env = '{"policies": "${POLICYENV}"}'
+found_policy_path_with_env_expanded = '{"policies": "pOlIcYeNv"}'
+found_policy_path_missing_policy = '{"XXpoliciesXX": "found policy/path"}'
+found_config_default = '["found config/default"]'
+found_config_default_with_env = '["${CONFIGENV}"]'
+found_config_default_with_env_expanded = '["cOnFiGeNv"]'
+found_config_path = '["found config/path"]'
+
+
+class my_mock_open(io.StringIO):
+    """
+    This class acts like the mock_open function,
+    but is able to return different results dependent
+    on the path being opened, or even raise different
+    exceptions.
+    """
+
+    def __init__(self, fname, mode="r"):
+        """ Do the right thing for the filename
+        """
+        ce = os.getenv("CONFIG_EXISTS", "no")
+        pe = os.getenv("POLICY_EXISTS", "no")
+
+        # are we a file with data to be returned?
+        ret_data = {
+            "config/path": [ce, found_config_path],
+            "config/env": [ce, found_config_default_with_env],
+            default_config_path(): [ce, found_config_default],
+            "policy/path": [pe, found_policy_path],
+            "policy/env": [pe, found_policy_path_with_env],
+            default_policy_path(): [pe, policy_default],
+            "bad/policy3": ["yes", found_policy_path_missing_policy],
+        }
+
+        if fname in ret_data:
+            if ret_data[fname][0] == "yes":
+                super().__init__(ret_data[fname][1])
+                return
+
+        # These return specifc exceptions
+        if fname == "bad/config":
+            raise yaml.scanner.ScannerError()
+        if fname == "bad/policy":
+            raise ValueError()
+        if fname == "bad/policy2":
+            raise json.decoder.JSONDecodeError(msg="bad json", doc=fname, pos=1)
+        if fname == "other/error":
+            raise ZeroDivisionError()
+            # raise OSError(2, "ENOENT")
+
+        raise FileNotFoundError(fname)
+
+
+def test_config_file_both_exist(monkeypatch, monkeyed_requests_get):
+    """
+    These tests cover the cases where both the policy and configuration files exist.
+    We vary WHICH file is being pointed at using the environment variables.
+    """
+
+    monkeypatch.setattr("requests.get", monkeyed_requests_get)
+
+    monkeypatch.setenv("CONFIG_EXISTS", "yes")
+    monkeypatch.setenv("POLICY_EXISTS", "yes")
+    monkeypatch.setenv("CONFIGENV", "cOnFiGeNv")
+    monkeypatch.setenv("POLICYENV", "pOlIcYeNv")
+    for (config_path, expected_config, set_config) in [
+            ("config/path", json.loads(found_config_path), True),
+            ("config/env", json.loads(found_config_default_with_env_expanded), True),
+            ("", json.loads(found_config_default), True),
+            (None, json.loads(found_config_default), False)]:
+
+        if set_config:
+            monkeypatch.setenv("CBS_CLIENT_CONFIG_PATH", config_path)
+        else:
+            monkeypatch.delenv("CBS_CLIENT_CONFIG_PATH")
+
+        expected_get_config = {"config": expected_config}
+
+        for (policy_path, expected_policy, set_policy) in [
+                ("policy/path", json.loads(found_policy_path)['policies'], True),
+                ("policy/env", json.loads(found_policy_path_with_env)['policies'], True),
+                ("", json.loads(policy_default)['policies'], True),
+                (None, json.loads(policy_default)['policies'], False)]:
+
+            if set_policy:
+                monkeypatch.setenv("CBS_CLIENT_POLICY_PATH", policy_path)
+            else:
+                monkeypatch.delenv("CBS_CLIENT_POLICY_PATH")
+
+            expected_get_all = {"config": expected_config, "policies": expected_policy}
+
+            with patch('builtins.open', my_mock_open):
+                gc = get_config()
+                assert gc == expected_get_config
+
+                ga = get_all()
+                assert ga == expected_get_all
+
+
+def test_config_file_config_exists_policy_does_not(monkeypatch, monkeyed_requests_get):
+    """
+    In this test, the policy file is always missing. Its value is always defaulted to {}.
+    The test structure is identical to what we had in test_config_file_both_exist(), but
+    the expected configuration to be returned is different.
+    """
+
+    monkeypatch.setattr("requests.get", monkeyed_requests_get)
+
+    monkeypatch.setenv("CONFIG_EXISTS", "yes")
+    monkeypatch.setenv("POLICY_EXISTS", "no")
+
+    for (config_path, expected_config, set_config) in [
+            ("config/path", json.loads(found_config_path), True),
+            ("", json.loads(found_config_default), True),
+            (None, json.loads(found_config_default), False)]:
+
+        if set_config:
+            monkeypatch.setenv("CBS_CLIENT_CONFIG_PATH", config_path)
+        else:
+            monkeypatch.delenv("CBS_CLIENT_CONFIG_PATH")
+
+        expected_get_config = {"config": expected_config}
+        expected_get_all = {"config": expected_config}
+
+        for (policy_path, expected_policy, set_policy) in [
+                ("policy/path", json.loads(found_policy_path)['policies'], True),
+                ("", json.loads(policy_default)['policies'], True),
+                (None, json.loads(policy_default)['policies'], False)]:
+
+            if set_policy:
+                monkeypatch.setenv("CBS_CLIENT_POLICY_PATH", policy_path)
+            else:
+                monkeypatch.delenv("CBS_CLIENT_POLICY_PATH")
+
+            with patch('builtins.open', my_mock_open):
+                gc = get_config()
+                assert gc == expected_get_config
+
+                ga = get_all()
+                assert ga == expected_get_all
+
+
+def test_config_file_config_does_not_policy_exists(monkeypatch, monkeyed_requests_get):
+    """
+    In this test, the config file is always missing. Its value is always defaulted to
+    the CBS response.
+    The test structure is identical to what we had in test_config_file_both_exist(), but
+    the expected configuration to be returned is different.
+    """
+
+    monkeypatch.setattr("requests.get", monkeyed_requests_get)
+
+    monkeypatch.setenv("CONFIG_EXISTS", "no")
+    monkeypatch.setenv("POLICY_EXISTS", "yes")
+
+    expected_get_config = DEFAULT_REQUESTS_CONFIG
+    expected_get_all = DEFAULT_REQUESTS_CONFIG_ALL
+
+    for (config_path, expected_config, set_config) in [
+            ("config/path", json.loads(found_config_path), True),
+            ("", json.loads(found_config_default), True),
+            (None, json.loads(found_config_default), False)]:
+
+        if set_config:
+            monkeypatch.setenv("CBS_CLIENT_CONFIG_PATH", config_path)
+        else:
+            monkeypatch.delenv("CBS_CLIENT_CONFIG_PATH")
+
+        for (policy_path, expected_policy, set_policy) in [
+                ("policy/path", json.loads(found_policy_path)['policies'], True),
+                ("", json.loads(policy_default)['policies'], True),
+                (None, json.loads(policy_default)['policies'], False)]:
+
+            if set_policy:
+                monkeypatch.setenv("CBS_CLIENT_POLICY_PATH", policy_path)
+            else:
+                monkeypatch.delenv("CBS_CLIENT_POLICY_PATH")
+
+            with patch('builtins.open', my_mock_open):
+                gc = get_config()
+                assert gc == expected_get_config
+
+                ga = get_all()
+                assert ga == expected_get_all
+
+
+def test_config_file_various_exceptions(monkeypatch, monkeyed_requests_get):
+    """
+    In this test, various forms of exceptions are tested while accessing the
+    configuration and policy files.
+    Exceptions on the policy file act as if the policy file does not exist.
+    Exceptions on the configuration file act as if the configuration file does not exist.
+    """
+
+    monkeypatch.setattr("requests.get", monkeyed_requests_get)
+
+    monkeypatch.setenv("CONFIG_EXISTS", "yes")
+    monkeypatch.setenv("POLICY_EXISTS", "yes")
+
+    # first do exceptions for the policy file
+    for (config_path, expected_config, set_config) in [
+            ("config/path", json.loads(found_config_path), True),
+            ("", json.loads(found_config_default), True),
+            (None, json.loads(found_config_default), False)]:
+
+        if set_config:
+            monkeypatch.setenv("CBS_CLIENT_CONFIG_PATH", config_path)
+        else:
+            monkeypatch.delenv("CBS_CLIENT_CONFIG_PATH")
+
+        expected_get_config = {"config": expected_config}
+        expected_get_all = {"config": expected_config}
+
+        for policy_path in ["bad/policy", "bad/policy2",
+                            "bad/policy3", "other/error"]:
+
+            monkeypatch.setenv("CBS_CLIENT_POLICY_PATH", policy_path)
+
+            with patch('builtins.open', my_mock_open):
+                gc = get_config()
+                assert gc == expected_get_config
+
+                ga = get_all()
+                assert ga == expected_get_all
+
+    # next do exceptions for the config file
+    expected_get_config = DEFAULT_REQUESTS_CONFIG
+    expected_get_all = DEFAULT_REQUESTS_CONFIG_ALL
+
+    policy_path = "policy/path"
+    monkeypatch.setenv("CBS_CLIENT_POLICY_PATH", policy_path)
+
+    for config_path in ["bad/config", "other/error"]:
+
+        monkeypatch.setenv("CBS_CLIENT_CONFIG_PATH", config_path)
+
+        with patch('builtins.open', my_mock_open):
+            gc = get_config()
+            assert gc == expected_get_config
+
+            ga = get_all()
+            assert ga == expected_get_all
diff --git a/onap-dcae-cbs-docker-client/tox.ini b/onap-dcae-cbs-docker-client/tox.ini
index 04b292e..5f6d8f8 100644
--- a/onap-dcae-cbs-docker-client/tox.ini
+++ b/onap-dcae-cbs-docker-client/tox.ini
@@ -1,12 +1,15 @@
 # content of: tox.ini , put in same dir as setup.py
 [tox]
-envlist = py36, flake8, py38, py39
+# envlist = py36, flake8, py38, py39
+envlist = flake8, py38, py39
 
 [testenv]
 deps=
     pytest
     coverage
     pytest-cov
+    pyyaml
+
 setenv =
     HOSTNAME = testhostname
     CONFIG_BINDING_SERVICE = config-binding-service
@@ -14,7 +17,7 @@ setenv =
     TEST_ENV=test_env
 
 commands=
-    pytest --junitxml xunit-results.xml --cov onap_dcae_cbs_docker_client --cov-report xml
+    pytest --junitxml xunit-results.xml --cov onap_dcae_cbs_docker_client --cov-report xml --cov-report=term --cov-report=html
     coverage xml
 
 [testenv:flake8]
diff --git a/scripts/mvn-phase-lib.sh b/scripts/mvn-phase-lib.sh
index 47bcd06..c9e8db9 100644
--- a/scripts/mvn-phase-lib.sh
+++ b/scripts/mvn-phase-lib.sh
@@ -231,12 +231,13 @@ run_tox_test()
     DIR=$(echo "$TOXINI" | rev | cut -f2- -d'/' | rev)
     cd "${CURDIR}/${DIR}"
     rm -rf ./venv-tox ./.tox
-    virtualenv ./venv-tox
+    python3 -m venv ./venv-tox
     source ./venv-tox/bin/activate
-    pip install pip==9.0.3
-    pip install --upgrade argparse
-    pip install tox==2.9.1
-    pip freeze
+
+    pip3 install pip==9.0.3
+    pip3 install --upgrade argparse
+    pip3 install tox==2.9.1
+    pip3 freeze
     tox
     deactivate
     rm -rf ./venv-tox ./.tox
@@ -248,11 +249,12 @@ build_wagons()
   rm -rf ./*.wgn venv-pkg
   SETUPFILES=$(find . -name "setup.py")
   
-  virtualenv ./venv-pkg
+  python3 -m venv ./venv-pkg
   source ./venv-pkg/bin/activate
-  pip install --upgrade pip 
-  pip install wagon
-  
+
+  pip3 install --upgrade pip
+  pip3 install wagon
+
   CURDIR=$(pwd)
   for SETUPFILE in $SETUPFILES; do
     PLUGIN_DIR=$(dirname "$SETUPFILE")