Process Operation Context Params in Endpoints

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/CommandGenerator.java

@@ -299,6 +299,14 @@ private void generateEndpointParameterInstructionProvider() {
                 }
                 paramNames.add(name);
             });
+
+            parameterFinder.getOperationContextParamValues(operation).forEach((name, jmesPathForInputInJs) -> {
+                writer.write(
+                    """
+                    $L: { type: \"operationContextParams\", name: $L },
+                    """,
+                    name, jmesPathForInputInJs);
+            });
         }
         writer.write("})")
             .dedent();

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/RuleSetParameterFinder.java

@@ -32,6 +32,7 @@
 import software.amazon.smithy.rulesengine.traits.ClientContextParamsTrait;
 import software.amazon.smithy.rulesengine.traits.ContextParamTrait;
 import software.amazon.smithy.rulesengine.traits.EndpointRuleSetTrait;
+import software.amazon.smithy.rulesengine.traits.OperationContextParamsTrait;
 import software.amazon.smithy.rulesengine.traits.StaticContextParamsTrait;
 import software.amazon.smithy.utils.SmithyInternalApi;
 
@@ -152,6 +153,68 @@ public Map<String, String> getContextParams(Shape operationInput) {
         return map;
     }
 
+    /**
+     * Get map of params to JavaScript equivalent of provided JMESPath expressions.
+     */
+    public Map<String, String> getOperationContextParamValues(OperationShape operation) {
+        Map<String, String> map = new HashMap<>();
+
+        Optional<OperationContextParamsTrait> trait = operation.getTrait(OperationContextParamsTrait.class);
+        if (trait.isPresent()) {
+            trait.get().getParameters().forEach((name, definition) -> {
+                String separator = ".";
+                String value = "this" + separator + "input";
+                String path = definition.getPath();
+
+                // Split JMESPath expression string on separator and add JavaScript equivalent.
+                for (String part : path.split("[" + separator + "]")) {
+                    if (value.endsWith(")")) {
+                        // The value is an object, which needs to run on map.
+                        value += ".map(obj => obj";
+                    }
+
+                    // Process keys https://jmespath.org/specification.html#keys
+                    if (part.startsWith("keys(")) {
+                        // Get provided object for which keys are to be extracted.
+                        String object = part.substring(5, part.length() - 1);
+                        value = "Object.keys(" + value + separator + object + ")";
+                        continue;
+                    }
+
+                    // Process list wildcard expression https://jmespath.org/specification.html#wildcard-expressions
+                    if (part.equals("*") || part.equals("[*]")) {
+                        value = "Object.values(" + value + ")";
+                        continue;
+                    }
+
+                    // Process hash wildcard expression https://jmespath.org/specification.html#wildcard-expressions
+                    if (part.endsWith("[*]")) {
+                        // Get key to run hash wildcard on.
+                        String key = part.substring(0, part.length() - 3);
+                        value = value + separator + key + separator + "map(obj => obj";
+                        continue;
+                    }
+
+                    // Treat remaining part as identifier without spaces https://jmespath.org/specification.html#identifiers
+                    value += separator + part;
+                }
+
+                // Remove no-op map, if it exists.
+                if (value.endsWith(separator + "map(obj => obj")) {
+                    value = value.substring(0, value.length() - 15);
+                }
+
+                // Close all open brackets.
+                value += ")".repeat((int) (
+                    value.chars().filter(ch -> ch == '(').count() - value.chars().filter(ch -> ch == ')').count()));
+
+                map.put(name, value);
+            });
+        }
+
+        return map;
+    }
+
     private static class RuleSetParameterFinderVisitor extends NodeVisitor.Default<Void> {
         private final Map<String, String> map;
 

smithy-typescript-codegen/src/test/java/software/amazon/smithy/typescript/codegen/CommandGeneratorTest.java

@@ -14,46 +14,64 @@ public class CommandGeneratorTest {
     public void addsCommandSpecificPlugins() {
         testCommmandCodegen(
             "output-structure.smithy",
-            "getSerdePlugin(config, this.serialize, this.deserialize)"
+            new String[] {"getSerdePlugin(config, this.serialize, this.deserialize)"}
         );
     }
 
     @Test
     public void writesSerializer() {
         testCommmandCodegen(
             "output-structure.smithy",
-            ".ser("
+            new String[] {".ser("}
         );
     }
 
     @Test
     public void writesDeserializer() {
         testCommmandCodegen(
             "output-structure.smithy",
-        ".de("
+            new String[] {".de("}
         );
     }
 
-    private void testCommmandCodegen(String file, String expectedType) {
-        Model model = Model.assembler()
-                .addImport(getClass().getResource(file))
-                .assemble()
-                .unwrap();
+    @Test
+    public void writesOperationContextParamValues() {
+        testCommmandCodegen(
+            "endpointsV2/endpoints-operation-context-params.smithy",
+            new String[] {
+                "opContextParamIdentifier: { type: \"operationContextParams\", name: this.input.fooString }",
+                "opContextParamSubExpression: { type: \"operationContextParams\", name: this.input.fooObj.bar }",
+                "opContextParamWildcardExpressionList: { type: \"operationContextParams\", name: this.input.fooList }",
+                "opContextParamWildcardExpressionListObj: { type: \"operationContextParams\", name: this.input.fooListObj.map(obj => obj.key) }",
+                "opContextParamWildcardExpressionHash: { type: \"operationContextParams\", name: Object.values(this.input.fooObjObj).map(obj => obj.bar) }",
+                "opContextParamKeys: { type: \"operationContextParams\", name: Object.keys(this.input.fooKeys) }",
+            }
+        );
+    }
+
+    private void testCommmandCodegen(String filename, String[] expectedTypeArray) {
         MockManifest manifest = new MockManifest();
         PluginContext context = PluginContext.builder()
-                .model(model)
-                .fileManifest(manifest)
-                .settings(Node.objectNodeBuilder()
-                                  .withMember("service", Node.from("smithy.example#Example"))
-                                  .withMember("package", Node.from("example"))
-                                  .withMember("packageVersion", Node.from("1.0.0"))
-                                  .build())
-                .build();
+            .pluginClassLoader(getClass().getClassLoader())
+            .model(Model.assembler()
+                .addImport(getClass().getResource(filename))
+                .discoverModels()
+                .assemble()
+                .unwrap())
+            .fileManifest(manifest)
+            .settings(Node.objectNodeBuilder()
+                .withMember("service", Node.from("smithy.example#Example"))
+                .withMember("package", Node.from("example"))
+                .withMember("packageVersion", Node.from("1.0.0"))
+                .build())
+            .build();
 
         new TypeScriptCodegenPlugin().execute(context);
         String contents = manifest.getFileString(CodegenUtils.SOURCE_FOLDER + "//commands/GetFooCommand.ts").get();
 
         assertThat(contents, containsString("as __MetadataBearer"));
-        assertThat(contents, containsString(expectedType));
+        for (String expectedType : expectedTypeArray) {
+            assertThat(contents, containsString(expectedType));
+        }
     }
 }

smithy-typescript-codegen/src/test/resources/software/amazon/smithy/typescript/codegen/endpointsV2/endpoints-operation-context-params.smithy

@@ -0,0 +1,80 @@
+$version: "2.0"
+
+namespace smithy.example
+
+@smithy.rules#endpointRuleSet({
+    version: "1.0",
+    parameters: {
+        opContextParamIdentifier: {
+            type: "string",
+        },
+        opContextParamSubExpression: {
+            type: "string",
+        },
+        opContextParamWildcardExpressionList: {
+            type: "stringArray",
+        },
+        opContextParamWildcardExpressionListObj: {
+            type: "stringArray",
+        },
+        opContextParamWildcardExpressionHash: {
+            type: "stringArray",
+        },
+        opContextParamKeys: {
+            type: "stringArray",
+        },
+    },
+    rules: []
+})
+service Example {
+    version: "1.0.0",
+    operations: [GetFoo]
+}
+
+@smithy.rules#operationContextParams(
+    "opContextParamIdentifier": { path: "fooString" }
+    "opContextParamSubExpression": { path: "fooObj.bar" }
+    "opContextParamWildcardExpressionList": { path: "fooList[*]" }
+    "opContextParamWildcardExpressionListObj": { path: "fooListObj[*].key" }
+    "opContextParamWildcardExpressionHash": { path: "fooObjObj.*.bar" }
+    "opContextParamKeys": { path: "keys(fooKeys)" }
+)
+operation GetFoo {
+    input: GetFooInput,
+    output: GetFooOutput,
+    errors: [GetFooError]
+}
+
+structure GetFooInput {
+    fooKeys: FooObject,
+    fooList: FooList,
+    fooListObj: FooListObj,
+    fooObj: FooObject,
+    fooObjObj: FooObjectObject,
+    fooString: String,
+}
+
+structure FooObject {
+    bar: String
+}
+
+structure FooObjectObject {
+    baz: FooObject
+}
+
+list FooList {
+    member: String
+}
+
+list FooListObj {
+    member: FooListObjMember
+}
+
+structure FooListObjMember {
+    key: String
+}
+
+structure GetFooOutput {}
+
+@error("client")
+structure GetFooError {}