Support custom endpoint URLs

README.md

@@ -22,6 +22,8 @@ The default location of the configuration file used by collectd-cloudwatch plugi
  * __credentials_path__ - Used to point to AWS account configuration file
  * __region__ - Manual override for [region](http://docs.aws.amazon.com/general/latest/gr/rande.html#cw_region)  used to publish metrics
  * __host__ - Manual override for EC2 Instance ID and Host information propagated by collectd
+ * __ec2_endpoint_url__ - Manual override for EC2 endpoint
+ * __monitoring_endpoint_url__ - Manual override for Monitoring endpoint
  * __proxy_server_name__ - Manual override for proxy server name, used by plugin to connect aws cloudwatch at *.amazonaws.com.
  * __proxy_server_port__ - Manual override for proxy server port, used by plugin to connect aws cloudwatch at *.amazonaws.com.
  * __enable_high_resolution_metrics__ - The storage resolution is for high resolution support

src/cloudwatch/modules/client/baserequestbuilder.py

@@ -1,6 +1,9 @@
-from ..awsutils import get_aws_timestamp, get_datestamp
-from signer import Signer
+import re
+
 from querystringbuilder import QuerystringBuilder
+from signer import Signer
+from ..awsutils import get_aws_timestamp, get_datestamp
+
 
 class BaseRequestBuilder(object):
     """
@@ -17,7 +20,8 @@ class BaseRequestBuilder(object):
     _ALGORITHM = "AWS4-HMAC-SHA256"
     _V4_TERMINATOR = "aws4_request"
 
-    def __init__(self, credentials, region, service, action, api_version, enable_high_resolution_metrics=False):
+    def __init__(self, endpoint, credentials, region, service, action, api_version, enable_high_resolution_metrics=False):
+        self.endpoint = endpoint
         self.credentials = credentials
         self.region = region
         self.datestamp = None
@@ -61,4 +65,16 @@ def _get_request_map(self):
         }
         if self.credentials.token:
             canonical_map["X-Amz-Security-Token"] = self.credentials.token
-        return canonical_map
+        return canonical_map
+
+    def _get_host(self):
+        """ Returns the endpoint's hostname derived from the endpoint """
+        match = re.search(r"http://(.*)/", self.endpoint)
+        if match:
+            return match.group(1)
+
+        match = re.search(r"https://(.*)/", self.endpoint)
+        if match:
+            return match.group(1)
+
+        raise ValueError("Cannot extract endpoint hostname")

src/cloudwatch/modules/client/ec2getclient.py

@@ -25,7 +25,7 @@ class EC2GetClient(object):
     _TOTAL_RETRIES = 1
 
     def __init__(self, config_helper, connection_timeout=_DEFAULT_CONNECTION_TIMEOUT, response_timeout=_DEFAULT_RESPONSE_TIMEOUT):
-        self.request_builder = EC2RequestBuilder(config_helper.credentials, config_helper.region)
+        self.request_builder = EC2RequestBuilder(config_helper.ec2_endpoint, config_helper.credentials, config_helper.region)
         self._validate_and_set_endpoint(config_helper.ec2_endpoint)
         self.timeout = (connection_timeout, response_timeout)
 

src/cloudwatch/modules/client/ec2requestbuilder.py

@@ -13,8 +13,8 @@ class EC2RequestBuilder(BaseRequestBuilder):
     _ACTION = "DescribeTags"
     _API_VERSION = "2016-11-15"
 
-    def __init__(self, credentials, region):
-        super(self.__class__, self).__init__(credentials, region, self._SERVICE, self._ACTION, self._API_VERSION)
+    def __init__(self, ec2_endpoint, credentials, region):
+        super(self.__class__, self).__init__(ec2_endpoint, credentials, region, self._SERVICE, self._ACTION, self._API_VERSION)
 
     def create_signed_request(self, request_map):
         """ Creates a ready to send request with metrics from the metric list passed as parameter """
@@ -32,11 +32,3 @@ def _create_canonical_querystring(self, request_map):
         http://docs.aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html 
         """
         return self.querystring_builder.build_querystring_from_map(request_map, self._get_request_map())
-
-    def _get_host(self):
-        """ Returns the endpoint's hostname derived from the region """
-        if self.region == "localhost":
-            return "localhost"
-        elif self.region.startswith("cn-"):
-            return "ec2." + self.region + ".amazonaws.com.cn"
-        return "ec2." + self.region + ".amazonaws.com"

src/cloudwatch/modules/client/putclient.py

@@ -29,7 +29,7 @@ class PutClient(object):
     _LOG_FILE_MAX_SIZE = 10*1024*1024
 
     def __init__(self, config_helper, connection_timeout=_DEFAULT_CONNECTION_TIMEOUT, response_timeout=_DEFAULT_RESPONSE_TIMEOUT):
-        self.request_builder = RequestBuilder(config_helper.credentials, config_helper.region, config_helper.enable_high_resolution_metrics)
+        self.request_builder = RequestBuilder(config_helper.endpoint, config_helper.credentials, config_helper.region, config_helper.enable_high_resolution_metrics)
         self._validate_and_set_endpoint(config_helper.endpoint)
         self.timeout = (connection_timeout, response_timeout)
         self.proxy_server_name = config_helper.proxy_server_name

src/cloudwatch/modules/client/requestbuilder.py

@@ -13,8 +13,8 @@ class RequestBuilder(BaseRequestBuilder):
     _ACTION = "PutMetricData"
     _API_VERSION = "2010-08-01"
 
-    def __init__(self, credentials, region, enable_high_resolution_metrics):
-        super(self.__class__, self).__init__(credentials, region, self._SERVICE, self._ACTION, self._API_VERSION, enable_high_resolution_metrics)
+    def __init__(self, endpoint, credentials, region, enable_high_resolution_metrics):
+        super(self.__class__, self).__init__(endpoint, credentials, region, self._SERVICE, self._ACTION, self._API_VERSION, enable_high_resolution_metrics)
         self.namespace = ""
 
     def create_signed_request(self, namespace, metric_list):
@@ -44,11 +44,3 @@ def _get_namespace_request_map(self):
         if (self.namespace):
             canonical_map["Namespace"] = self.namespace
         return canonical_map
-
-    def _get_host(self):
-        """ Returns the endpoint's hostname derived from the region """
-        if self.region == "localhost":
-            return "localhost"
-        elif self.region.startswith("cn-"):
-            return "monitoring." + self.region + ".amazonaws.com.cn"
-        return "monitoring." + self.region + ".amazonaws.com"

src/cloudwatch/modules/configuration/confighelper.py

@@ -139,7 +139,11 @@ def _load_hostname(self):
                     " Using host information provided by Collectd.")
 
     def _set_ec2_endpoint(self):
-        """ Creates endpoint from region information """
+        """ Creates endpoint from region information (if the endpoint not explicitly set via ec2_endpoint_url) """
+        if self.config_reader.ec2_endpoint_url:
+            self.ec2_endpoint = self.config_reader.ec2_endpoint_url
+            return
+
         if self.region is "localhost":
             self.ec2_endpoint = "http://" + self.region + "/"
         elif self.region.startswith("cn-"):
@@ -179,7 +183,11 @@ def _load_flush_interval_in_seconds(self):
             self._LOGGER.warning("flush_interval_in_seconds in configuration is invalid: " + str(self.config_reader.flush_interval_in_seconds) + " use the default value: " + self.flush_interval_in_seconds)
 
     def _set_endpoint(self):
-        """ Creates endpoint from region information """
+        """ Creates endpoint from region information (if the endpoint not explicitly set via monitoring_endpoint_url) """
+        if self.config_reader.monitoring_endpoint_url:
+            self.endpoint = self.config_reader.monitoring_endpoint_url
+            return
+
         if self.region is "localhost":
             self.endpoint = "http://" + self.region + "/"
         elif self.region.startswith("cn-"):

src/cloudwatch/modules/configuration/configreader.py

@@ -39,6 +39,8 @@ class ConfigReader(object):
     PROXY_SERVER_PORT_KEY = "proxy_server_port"
     ENABLE_HIGH_DEFINITION_METRICS = "enable_high_resolution_metrics"
     FLUSH_INTERVAL_IN_SECONDS = "flush_interval_in_seconds"
+    EC2_ENDPOINT_URL = "ec2_endpoint_url"
+    MONITORING_ENDPOINT_URL = "monitoring_endpoint_url"
 
     def __init__(self, config_path):
         self.config_path = config_path
@@ -78,3 +80,5 @@ def _parse_config_file(self):
         self.push_asg = self.reader_utils.try_get_boolean(self.PUSH_ASG_KEY, self._PUSH_ASG_DEFAULT_VALUE)
         self.push_constant = self.reader_utils.try_get_boolean(self.PUSH_CONSTANT_KEY, self._PUSH_CONSTANT_DEFAULT_VALUE)
         self.constant_dimension_value = self.reader_utils.get_string(self.CONSTANT_DIMENSION_KEY)
+        self.ec2_endpoint_url = self.reader_utils.get_string(self.EC2_ENDPOINT_URL)
+        self.monitoring_endpoint_url = self.reader_utils.get_string(self.MONITORING_ENDPOINT_URL)

test/test_requestbuilder.py

@@ -12,13 +12,13 @@ def setUp(self):
         self.region = "test_region"
         self.namespace = "test_namespace"
         self.credentials = AWSCredentials("access_key", "secret_key")
-        self.builder = RequestBuilder(self.credentials, self.region, "10")
+        self.builder = RequestBuilder("https://monitoring." + self.region + ".amazonaws.com/", self.credentials, self.region, "10")
 
     def test_get_host(self):
         self.assertEquals("monitoring." + self.region +".amazonaws.com", self.builder._get_host())
 
-    def test_get_host_for_localhost_region(self):
-        self.builder.region = "localhost"
+    def test_get_host_for_localhost_endpoint(self):
+        self.builder.endpoint = "http://localhost/"
         self.assertEquals("localhost", self.builder._get_host())
 
     def test_get_signed_headers(self):
@@ -54,7 +54,7 @@ def test_create_signed_request_generates_all_required_parameters(self):
         self.assertTrue("X-Amz-SignedHeaders" in request)
 
     def test_create_signed_request_with_iam_role_has_token_parameter(self):
-        self.builder = RequestBuilder(AWSCredentials("access_key", "secret_key", "token"), self.region, "10")
+        self.builder = RequestBuilder("https://localhost/", AWSCredentials("access_key", "secret_key", "token"), self.region, "10")
         metric = MetricDataStatistic("test_metric", statistic_values=MetricDataStatistic.Statistics(20))
         request = self.builder.create_signed_request(self.namespace, [metric])
         self.assertTrue("X-Amz-Security-Token" in request)