Cleanups from PR (still todo: seperate into generic user agent and aws user agent).

Author: alextwoods

codegen/aws/core/src/main/java/software/amazon/smithy/python/aws/codegen/AwsUserAgentIntegration.java

@@ -4,7 +4,6 @@
  */
 package software.amazon.smithy.python.aws.codegen;
 
-import java.util.Collections;
 import java.util.List;
 import software.amazon.smithy.codegen.core.Symbol;
 import software.amazon.smithy.codegen.core.SymbolReference;
@@ -24,12 +23,11 @@ public List<RuntimeClientPlugin> getClientPlugins() {
                 RuntimeClientPlugin.builder()
                         .addConfigProperty(
                                 ConfigProperty.builder()
-                                // TODO: This is the name used in boto, but potentially could be user_agent_prefix.  Depends on backwards compat strategy.
-                                .name("user_agent_extra")
-                                .documentation("Additional suffix to be added to the User-Agent header.")
-                                .type(Symbol.builder().name("str").build()) // TODO: Should common types like this be defined as constants somewhere?
-                                .nullable(true)
-                                .build())
+                                        .name("user_agent_extra")
+                                        .documentation("Additional suffix to be added to the User-Agent header.")
+                                        .type(Symbol.builder().name("str").build())
+                                        .nullable(true)
+                                        .build())
                         .addConfigProperty(
                                 ConfigProperty.builder()
                                         .name("sdk_ua_app_id")

packages/smithy-aws-core/src/smithy_aws_core/interceptors/user_agent.py

@@ -12,14 +12,17 @@ class UserAgentInterceptor(Interceptor[Request, None, HTTPRequest, None]):
 
     def __init__(
         self,
+        *,
         ua_suffix: str | None = None,
         ua_app_id: str | None = None,
         sdk_version: str | None = "0.0.1",
     ) -> None:
         """Initialize the UserAgentInterceptor.
 
-        :ua_suffix: Additional suffix to be added to the UserAgent header. :ua_app_id:
-        User defined and opaque application ID to be added to the UserAgent header.
+        :param ua_suffix: Additional suffix to be added to the UserAgent header.
+        :param ua_app_id: User defined and opaque application ID to be added to the
+            UserAgent header.
+        :param sdk_version: SDK version to be added to the UserAgent header.
         """
         super().__init__()
         self._ua_suffix = ua_suffix

packages/smithy-aws-core/src/smithy_aws_core/user_agent.py

@@ -4,8 +4,9 @@
 
 import os
 import platform
+from dataclasses import dataclass
 from string import ascii_letters, digits
-from typing import NamedTuple, Optional, Self, Union, List
+from typing import Self
 
 from smithy_http.aio.crt import HAS_CRT
 
@@ -24,7 +25,8 @@
 _USERAGENT_SDK_NAME = "aws-sdk-python"
 
 
-class UserAgentComponent(NamedTuple):
+@dataclass(frozen=True, slots=True)
+class UserAgentComponent:
     """Component of a User-Agent header string in the standard format.
 
     Each component consists of a prefix, a name, and a value. In the string
@@ -37,7 +39,7 @@ class UserAgentComponent(NamedTuple):
     name: str
     value: str | None = None
 
-    def to_string(self):
+    def __str__(self):
         """Create string like 'prefix/name#value' from a UserAgentComponent."""
         clean_prefix = sanitize_user_agent_string_component(
             self.prefix, allow_hash=True
@@ -59,11 +61,11 @@ class RawStringUserAgentComponent:
     def __init__(self, value: str):
         self._value = value
 
-    def to_string(self) -> str:
+    def __str__(self) -> str:
         return self._value
 
 
-_UAComponent = Union[UserAgentComponent, RawStringUserAgentComponent]
+_UAComponent = UserAgentComponent | RawStringUserAgentComponent
 
 
 class UserAgent:
@@ -92,17 +94,14 @@ def __init__(
 
     @classmethod
     def from_environment(cls) -> Self:
-        crt_version = None
-        if HAS_CRT:
-            crt_version = _get_crt_version() or "Unknown"
         return cls(
             platform_name=platform.system(),
             platform_version=platform.release(),
             platform_machine=platform.machine(),
             python_version=platform.python_version(),
             python_implementation=platform.python_implementation(),
             execution_env=os.environ.get("AWS_EXECUTION_ENV"),
-            crt_version=crt_version,
+            crt_version=_get_crt_version(),
         )
 
     def with_config(
@@ -130,7 +129,7 @@ def to_string(self) -> str:
             *self._build_suffix(),
         ]
 
-        return " ".join([comp.to_string() for comp in components])
+        return " ".join([str(comp) for comp in components])
 
     def _build_sdk_metadata(self) -> list[UserAgentComponent]:
         """Build the SDK name and version component of the User-Agent header.
@@ -261,9 +260,9 @@ def sanitize_user_agent_string_component(raw_str: str, allow_hash: bool = False)
 
 def _get_crt_version() -> str | None:
     """This function is considered private and is subject to abrupt breaking changes."""
-    try:
+    if HAS_CRT:
         import awscrt
 
         return awscrt.__version__
-    except AttributeError:
+    else:
         return None