exporter/zipkin: adding support for env var OTEL_EXPORTER_ZIPKIN_ENDP…

…OINT (#1064)

* add support for env var: OTEL_EXPORTER_ZIPKIN_ENDPOINT
* update method signature to use url

exporter/opentelemetry-exporter-zipkin/CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ## Unreleased
 
+- Add support for OTEL_EXPORTER_ZIPKIN_ENDPOINT env var. As part of this change, the 
+  configuration of the ZipkinSpanExporter exposes a `url` argument to replace `host_name`,
+  `port`, `protocol`, `endpoint`. This brings this implementation inline with other
+  implementations. 
+  ([#1064](https://github.com/open-telemetry/opentelemetry-python/pull/1064))
+
 ## Version 0.12b0
 
 Released 2020-08-14

exporter/opentelemetry-exporter-zipkin/src/opentelemetry/exporter/zipkin/__init__.py

@@ -24,6 +24,7 @@
 
 .. _Zipkin: https://zipkin.io/
 .. _OpenTelemetry: https://github.com/open-telemetry/opentelemetry-python/
+.. _Specification: https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/sdk-environment-variables.md#zipkin-exporter
 
 .. code:: python
 
@@ -39,10 +40,7 @@
     zipkin_exporter = zipkin.ZipkinSpanExporter(
         service_name="my-helloworld-service",
         # optional:
-        # host_name="localhost",
-        # port=9411,
-        # endpoint="/api/v2/spans",
-        # protocol="http",
+        # url="http://localhost:9411/api/v2/spans",
         # ipv4="",
         # ipv6="",
         # retry=False,
@@ -57,24 +55,25 @@
     with tracer.start_as_current_span("foo"):
         print("Hello world!")
 
+The exporter supports endpoint configuration via the OTEL_EXPORTER_ZIPKIN_ENDPOINT environment variables as defined in the `Specification`_
+
 API
 ---
 """
 
 import json
 import logging
+import os
 from typing import Optional, Sequence
+from urllib.parse import urlparse
 
 import requests
 
 from opentelemetry.sdk.trace.export import SpanExporter, SpanExportResult
 from opentelemetry.trace import Span, SpanContext, SpanKind
 
-DEFAULT_ENDPOINT = "/api/v2/spans"
-DEFAULT_HOST_NAME = "localhost"
-DEFAULT_PORT = 9411
-DEFAULT_PROTOCOL = "http"
 DEFAULT_RETRY = False
+DEFAULT_URL = "http://localhost:9411/api/v2/spans"
 ZIPKIN_HEADERS = {"Content-Type": "application/json"}
 
 SPAN_KIND_MAP = {
@@ -96,10 +95,7 @@ class ZipkinSpanExporter(SpanExporter):
     Args:
         service_name: Service that logged an annotation in a trace.Classifier
             when query for spans.
-        host_name: The host name of the Zipkin server
-        port: The port of the Zipkin server
-        endpoint: The endpoint of the Zipkin server
-        protocol: The protocol used for the request.
+        url: The Zipkin endpoint URL
         ipv4: Primary IPv4 address associated with this connection.
         ipv6: Primary IPv6 address associated with this connection.
         retry: Set to True to configure the exporter to retry on failure.
@@ -108,22 +104,21 @@ class ZipkinSpanExporter(SpanExporter):
     def __init__(
         self,
         service_name: str,
-        host_name: str = DEFAULT_HOST_NAME,
-        port: int = DEFAULT_PORT,
-        endpoint: str = DEFAULT_ENDPOINT,
-        protocol: str = DEFAULT_PROTOCOL,
+        url: str = None,
         ipv4: Optional[str] = None,
         ipv6: Optional[str] = None,
         retry: Optional[str] = DEFAULT_RETRY,
     ):
         self.service_name = service_name
-        self.host_name = host_name
-        self.port = port
-        self.endpoint = endpoint
-        self.protocol = protocol
-        self.url = "{}://{}:{}{}".format(
-            self.protocol, self.host_name, self.port, self.endpoint
-        )
+        if url is None:
+            self.url = os.environ.get(
+                "OTEL_EXPORTER_ZIPKIN_ENDPOINT", DEFAULT_URL
+            )
+        else:
+            self.url = url
+
+        self.port = urlparse(self.url).port
+
         self.ipv4 = ipv4
         self.ipv6 = ipv6
         self.retry = retry

exporter/opentelemetry-exporter-zipkin/tests/test_zipkin_exporter.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 import json
+import os
 import unittest
 from unittest.mock import MagicMock, patch
 
@@ -43,54 +44,56 @@ def setUp(self):
         self._test_span.start()
         self._test_span.end()
 
+    def tearDown(self):
+        if "OTEL_EXPORTER_ZIPKIN_ENDPOINT" in os.environ:
+            del os.environ["OTEL_EXPORTER_ZIPKIN_ENDPOINT"]
+
+    def test_constructor_env_var(self):
+        """Test the default values assigned by constructor."""
+        url = "https://foo:9911/path"
+        os.environ["OTEL_EXPORTER_ZIPKIN_ENDPOINT"] = url
+        service_name = "my-service-name"
+        port = 9911
+        exporter = ZipkinSpanExporter(service_name)
+        ipv4 = None
+        ipv6 = None
+
+        self.assertEqual(exporter.service_name, service_name)
+        self.assertEqual(exporter.ipv4, ipv4)
+        self.assertEqual(exporter.ipv6, ipv6)
+        self.assertEqual(exporter.url, url)
+        self.assertEqual(exporter.port, port)
+
     def test_constructor_default(self):
         """Test the default values assigned by constructor."""
         service_name = "my-service-name"
-        host_name = "localhost"
         port = 9411
-        endpoint = "/api/v2/spans"
         exporter = ZipkinSpanExporter(service_name)
         ipv4 = None
         ipv6 = None
-        protocol = "http"
         url = "http://localhost:9411/api/v2/spans"
 
         self.assertEqual(exporter.service_name, service_name)
-        self.assertEqual(exporter.host_name, host_name)
         self.assertEqual(exporter.port, port)
-        self.assertEqual(exporter.endpoint, endpoint)
         self.assertEqual(exporter.ipv4, ipv4)
         self.assertEqual(exporter.ipv6, ipv6)
-        self.assertEqual(exporter.protocol, protocol)
         self.assertEqual(exporter.url, url)
 
     def test_constructor_explicit(self):
         """Test the constructor passing all the options."""
         service_name = "my-opentelemetry-zipkin"
-        host_name = "opentelemetry.io"
         port = 15875
-        endpoint = "/myapi/traces?format=zipkin"
         ipv4 = "1.2.3.4"
         ipv6 = "2001:0db8:85a3:0000:0000:8a2e:0370:7334"
-        protocol = "https"
         url = "https://opentelemetry.io:15875/myapi/traces?format=zipkin"
         exporter = ZipkinSpanExporter(
-            service_name=service_name,
-            host_name=host_name,
-            port=port,
-            endpoint=endpoint,
-            ipv4=ipv4,
-            ipv6=ipv6,
-            protocol=protocol,
+            service_name=service_name, url=url, ipv4=ipv4, ipv6=ipv6,
         )
 
         self.assertEqual(exporter.service_name, service_name)
-        self.assertEqual(exporter.host_name, host_name)
         self.assertEqual(exporter.port, port)
-        self.assertEqual(exporter.endpoint, endpoint)
         self.assertEqual(exporter.ipv4, ipv4)
         self.assertEqual(exporter.ipv6, ipv6)
-        self.assertEqual(exporter.protocol, protocol)
         self.assertEqual(exporter.url, url)
 
     # pylint: disable=too-many-locals