Implement endpoint generation

Author: alextwoods

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

@@ -0,0 +1,127 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package software.amazon.smithy.python.aws.codegen;
+
+import java.util.List;
+import software.amazon.smithy.aws.traits.ServiceTrait;
+import software.amazon.smithy.codegen.core.Symbol;
+import software.amazon.smithy.python.codegen.CodegenUtils;
+import software.amazon.smithy.python.codegen.ConfigProperty;
+import software.amazon.smithy.python.codegen.GenerationContext;
+import software.amazon.smithy.python.codegen.integrations.PythonIntegration;
+import software.amazon.smithy.python.codegen.integrations.RuntimeClientPlugin;
+import software.amazon.smithy.python.codegen.sections.EndpointParametersSection;
+import software.amazon.smithy.python.codegen.sections.EndpointResolverSection;
+import software.amazon.smithy.python.codegen.sections.InitDefaultEndpointResolverSection;
+import software.amazon.smithy.python.codegen.writer.PythonWriter;
+import software.amazon.smithy.utils.CodeInterceptor;
+import software.amazon.smithy.utils.CodeSection;
+
+public class AwsStandardRegionalEndpointsIntegration implements PythonIntegration {
+    @Override
+    public List<RuntimeClientPlugin> getClientPlugins(GenerationContext context) {
+        if (context.applicationProtocol().isHttpProtocol()) {
+            var region = ConfigProperty.builder()
+                    .name("region")
+                    .type(Symbol.builder().name("str").build())
+                    .documentation(" The AWS region to connect to. The configured region is used to "
+                            + "determine the service endpoint.")
+                    .build();
+            return List.of(
+                    RuntimeClientPlugin.builder()
+                            .addConfigProperty(region)
+                            .build());
+        } else {
+            return List.of();
+        }
+    }
+
+    @Override
+    public List<? extends CodeInterceptor<? extends CodeSection, PythonWriter>> interceptors(
+            GenerationContext context
+    ) {
+        return List.of(
+                new RegionalEndpointParametersInterceptor(context),
+                new RegionalEndpointResolverInterceptor(context),
+                new RegionalInitEndpointResolverInterceptor(context));
+    }
+
+    private static final class RegionalEndpointParametersInterceptor
+            implements CodeInterceptor<EndpointParametersSection, PythonWriter> {
+
+        private final GenerationContext context;
+
+        public RegionalEndpointParametersInterceptor(GenerationContext context) {
+            this.context = context;
+        }
+
+        @Override
+        public Class<EndpointParametersSection> sectionType() {
+            return EndpointParametersSection.class;
+        }
+
+        @Override
+        public void write(PythonWriter writer, String previousText, EndpointParametersSection section) {
+            var params = CodegenUtils.getEndpointParametersSymbol(context.settings());
+
+            writer.write("from smithy_aws_core.endpoints.standard_regional import RegionalEndpointParameters");
+            writer.write("$L = RegionalEndpointParameters", params.getName());
+        }
+    }
+
+    private static final class RegionalEndpointResolverInterceptor
+            implements CodeInterceptor<EndpointResolverSection, PythonWriter> {
+
+        private final GenerationContext context;
+
+        public RegionalEndpointResolverInterceptor(GenerationContext context) {
+            this.context = context;
+        }
+
+        @Override
+        public Class<EndpointResolverSection> sectionType() {
+            return EndpointResolverSection.class;
+        }
+
+        @Override
+        public void write(PythonWriter writer, String previousText, EndpointResolverSection section) {
+            var resolver = CodegenUtils.getEndpointResolverSymbol(context.settings());
+
+            writer.write("from smithy_aws_core.endpoints.standard_regional import StandardRegionalEndpointsResolver");
+            writer.write("$L = StandardRegionalEndpointsResolver", resolver.getName());
+        }
+    }
+
+    private static final class RegionalInitEndpointResolverInterceptor
+            implements CodeInterceptor<InitDefaultEndpointResolverSection, PythonWriter> {
+
+        private final GenerationContext context;
+
+        public RegionalInitEndpointResolverInterceptor(GenerationContext context) {
+            this.context = context;
+        }
+
+        @Override
+        public Class<InitDefaultEndpointResolverSection> sectionType() {
+            return InitDefaultEndpointResolverSection.class;
+        }
+
+        @Override
+        public void write(PythonWriter writer, String previousText, InitDefaultEndpointResolverSection section) {
+            var resolver = CodegenUtils.getEndpointResolverSymbol(context.settings());
+
+            String endpointPrefix = context.settings()
+                    .service(context.model())
+                    .getTrait(ServiceTrait.class)
+                    .map(ServiceTrait::getEndpointPrefix)
+                    .orElse(context.settings().service().getName());
+
+            writer.write("self.endpoint_resolver = endpoint_resolver or $T(endpoint_prefix=$S)",
+                    resolver,
+                    endpointPrefix);
+
+        }
+    }
+}

codegen/aws/core/src/main/resources/META-INF/services/software.amazon.smithy.python.codegen.integrations.PythonIntegration

@@ -6,3 +6,4 @@
 software.amazon.smithy.python.aws.codegen.AwsAuthIntegration
 software.amazon.smithy.python.aws.codegen.AwsProtocolsIntegration
 software.amazon.smithy.python.aws.codegen.AwsUserAgentIntegration
+software.amazon.smithy.python.aws.codegen.AwsStandardRegionalEndpointsIntegration