Add support for operation and service schemas (#413)

* Update weather example to use correct dependency

* Only import `Field` when single-value `httpHeader` is actually in the model

squish

* Add support for generating schemas for operations and service shapes

Author: haydenbaker

codegen/core/src/main/java/software/amazon/smithy/python/codegen/generators/SchemaGenerator.java

@@ -83,8 +83,7 @@ public static void generateAll(
         var index = TopologicalIndex.of(context.model());
         Stream.concat(index.getOrderedShapes().stream(), index.getRecursiveShapes().stream())
                 .filter(shapes::contains)
-                .filter(shape -> !shape.isOperationShape() && !shape.isResourceShape()
-                        && !shape.isServiceShape()
+                .filter(shape -> !shape.isResourceShape()
                         && !shape.isMemberShape()
                         && !Prelude.isPreludeShape(shape))
                 .filter(filter::apply)

codegen/core/src/main/java/software/amazon/smithy/python/codegen/integrations/HttpBindingProtocolGenerator.java

@@ -199,7 +199,7 @@ private void serializeHeaders(
     ) {
         writer.pushState(new SerializeFieldsSection(operation));
         writer.addDependency(SmithyPythonDependency.SMITHY_HTTP);
-        writer.addImports("smithy_http", Set.of("Field", "Fields"));
+        writer.addImport("smithy_http", "Fields");
         writer.write("""
                 headers = Fields(
                     [
@@ -234,9 +234,12 @@ private void writeContentType(GenerationContext context, PythonWriter writer, Op
         if (optionalContentType.isEmpty() && shouldWriteDefaultBody(context, operation)) {
             optionalContentType = Optional.of(getDocumentContentType());
         }
-        optionalContentType.ifPresent(contentType -> writer.write(
-                "Field(name=\"Content-Type\", values=[$S]),",
-                contentType));
+        if (optionalContentType.isPresent()) {
+            writer.addImport("smithy_http", "Field");
+            writer.write(
+                    "Field(name=\"Content-Type\", values=[$S]),",
+                    optionalContentType.get());
+        }
     }
 
     private void writeContentLength(GenerationContext context, PythonWriter writer, OperationShape operation) {
@@ -249,6 +252,7 @@ private void writeContentLength(GenerationContext context, PythonWriter writer,
             // The requiresLength trait, however, can force a length calculation.
             // see: https://smithy.io/2.0/spec/streaming.html#requireslength-trait
             if (requiresLength(context, operation)) {
+                writer.addImport("smithy_http", "Field");
                 writer.write("Field(name=\"Content-Length\", values=[str(content_length)]),");
             }
             return;
@@ -262,6 +266,7 @@ private void writeContentLength(GenerationContext context, PythonWriter writer,
                 .anyMatch(binding -> binding.getLocation() == PAYLOAD || binding.getLocation() == DOCUMENT);
 
         if (hasBodyBindings) {
+            writer.addImport("smithy_http", "Field");
             writer.write("Field(name=\"Content-Length\", values=[str(content_length)]),");
         }
     }
@@ -331,6 +336,7 @@ private void serializeIndividualHeaders(GenerationContext context, PythonWriter
                             headers.extend(tuples_to_fields(($S, $L) for e in input.$L$L))
                             """, binding.getLocationName(), inputValue, pythonName, trailer);
                 } else {
+                    writer.addImport("smithy_http", "Field");
                     var dataSource = "input." + pythonName;
                     var inputValue = target.accept(new HttpMemberSerVisitor(
                             context,

codegen/plugins/types/src/main/java/software/amazon/smithy/python/codegen/types/DirectedPythonTypeCodegen.java

@@ -64,6 +64,9 @@ public GenerationContext createContext(CreateContextDirective<PythonSettings, Py
     public void customizeBeforeShapeGeneration(CustomizeDirective<GenerationContext, PythonSettings> directive) {
         new ServiceErrorGenerator(directive.settings(), directive.context().writerDelegator()).run();
         SchemaGenerator.generateAll(directive.context(), directive.connectedShapes().values(), shape -> {
+            if (shape.isOperationShape() || shape.isServiceShape()) {
+                return false;
+            }
             if (shape.isStructureShape()) {
                 return shouldGenerateStructure(directive.settings(), shape);
             }

examples/weather/smithy-build.json

@@ -5,7 +5,7 @@
     "dependencies": [
       "software.amazon.smithy:smithy-model:[1.41.0,2.0)",
       "software.amazon.smithy:smithy-aws-traits:[1.41.0,2.0)",
-      "software.amazon.smithy.python:smithy-python-codegen:0.1.0"
+      "software.amazon.smithy.python.codegen:core:0.0.1"
     ]
   },
   "projections": {

packages/smithy-core/src/smithy_core/documents.py

@@ -94,7 +94,11 @@ def __init__(
         else:
             self._value = value
 
-        if self._schema.shape_type is not ShapeType.DOCUMENT:
+        if self._schema.shape_type not in (
+            ShapeType.DOCUMENT,
+            ShapeType.OPERATION,
+            ShapeType.SERVICE,
+        ):
             self._type = self._schema.shape_type
         else:
             # TODO: set an appropriate schema if one was not provided
@@ -311,6 +315,10 @@ def serialize_contents(self, serializer: ShapeSerializer) -> None:
                 raise SmithyException(
                     f"Unexpexcted DOCUMENT shape type for document value: {self.as_value()}"
                 )
+            case _:
+                raise SmithyException(
+                    f"Unexpected {self._type} shape type for document value: {self.as_value()}"
+                )
 
     def serialize_members(self, serializer: ShapeSerializer) -> None:
         for value in self.as_map().values():

packages/smithy-core/src/smithy_core/shapes.py

@@ -122,6 +122,6 @@ class ShapeType(Enum):
 
     # We won't acutally be using these, probably
     # MEMBER = 20
-    # SERVICE = 21
+    SERVICE = 21
     # RESOURCE = 22
-    # OPERATION = 23
+    OPERATION = 23