improvement(tree): Simpler JSON schema in non-polymorphic field cases (…

…microsoft#22538) Simplifies the JSON Schema output of `getJsonSchema` for non-polymorphic field cases from ```json "anyOf": [ { "$ref": "foo" } ] ``` to ```json "$ref": "foo" ```
pragya91 · Sep 17, 2024 · 5f3dc05 · 5f3dc05
1 parent ba93cde
commit 5f3dc05
Show file tree

Hide file tree

Showing 6 changed files with 78 additions and 137 deletions.
diff --git a/packages/dds/tree/api-report/tree.alpha.api.md b/packages/dds/tree/api-report/tree.alpha.api.md
@@ -200,15 +200,13 @@ export interface ITreeViewConfiguration<TSchema extends ImplicitFieldSchema = Im
 
 // @alpha @sealed
 export interface JsonArrayNodeSchema extends JsonNodeSchemaBase<NodeKind.Array, "array"> {
-    readonly items: {
-        anyOf: JsonSchemaRef[];
-    };
+    readonly items: JsonFieldSchema;
 }
 
 // @alpha @sealed
-export interface JsonFieldSchema {
+export type JsonFieldSchema = {
     readonly anyOf: JsonSchemaRef[];
-}
+} | JsonSchemaRef;
 
 // @alpha @sealed
 export interface JsonLeafNodeSchema extends JsonNodeSchemaBase<NodeKind.Leaf, JsonLeafSchemaType> {
@@ -256,9 +254,9 @@ export interface JsonSchemaRef {
 export type JsonSchemaType = "object" | "array" | JsonLeafSchemaType;
 
 // @alpha @sealed
-export interface JsonTreeSchema extends JsonFieldSchema {
+export type JsonTreeSchema = JsonFieldSchema & {
     readonly $defs: Record<JsonSchemaId, JsonNodeSchema>;
-}
+};
 
 // @public
 export type LazyItem<Item = unknown> = Item | (() => Item);

diff --git a/packages/dds/tree/src/simple-tree/api/jsonSchema.ts b/packages/dds/tree/src/simple-tree/api/jsonSchema.ts
@@ -103,18 +103,10 @@ export interface JsonObjectNodeSchema extends JsonNodeSchemaBase<NodeKind.Object
 export interface JsonArrayNodeSchema extends JsonNodeSchemaBase<NodeKind.Array, "array"> {
 	/**
 	 * The kinds of items allowed under the array.
-	 * @remarks Always represented via references to {@link JsonTreeSchema.$defs}.
 	 *
 	 * @see {@link https://json-schema.org/draft/2020-12/json-schema-core#name-items}.
 	 */
-	readonly items: {
-		/**
-		 * The kinds of items allowed under the array.
-		 * @remarks Always represented via references to {@link JsonTreeSchema.$defs}.
-		 * @see {@link https://json-schema.org/draft/2020-12/json-schema-core#name-anyof}.
-		 */
-		anyOf: JsonSchemaRef[];
-	};
+	readonly items: JsonFieldSchema;
 }
 
 /**
@@ -191,14 +183,16 @@ export type JsonNodeSchema =
  * @sealed
  * @alpha
  */
-export interface JsonFieldSchema {
-	/**
-	 * The kinds of items allowed under the field.
-	 * @remarks Always represented via references to {@link JsonTreeSchema.$defs}.
-	 * @see {@link https://json-schema.org/draft/2020-12/json-schema-core#name-anyof}.
-	 */
-	readonly anyOf: JsonSchemaRef[];
-}
+export type JsonFieldSchema =
+	| {
+			/**
+			 * The kinds of items allowed under the field, for polymorphic types.
+			 * @remarks Always represented via references to {@link JsonTreeSchema.$defs}.
+			 * @see {@link https://json-schema.org/draft/2020-12/json-schema-core#name-anyof}.
+			 */
+			readonly anyOf: JsonSchemaRef[];
+	  }
+	| JsonSchemaRef;
 
 /**
  * {@link https://json-schema.org/draft/2020-12/json-schema-core | JSON Schema} representation of a tree schema.
@@ -221,10 +215,10 @@ export interface JsonFieldSchema {
  * @sealed
  * @alpha
  */
-export interface JsonTreeSchema extends JsonFieldSchema {
+export type JsonTreeSchema = JsonFieldSchema & {
 	/**
 	 * The set of definitions reachable from this schema's root.
 	 * @see {@link https://json-schema.org/draft/2020-12/json-schema-core#name-schema-re-use-with-defs}
 	 */
 	readonly $defs: Record<JsonSchemaId, JsonNodeSchema>;
-}
+};
diff --git a/packages/dds/tree/src/simple-tree/api/simpleSchemaToJsonSchema.ts b/packages/dds/tree/src/simple-tree/api/simpleSchemaToJsonSchema.ts
@@ -3,7 +3,7 @@
  * Licensed under the MIT License.
  */
 
-import { unreachableCase } from "@fluidframework/core-utils/internal";
+import { oob, unreachableCase } from "@fluidframework/core-utils/internal";
 import { UsageError } from "@fluidframework/telemetry-utils/internal";
 import { ValueSchema } from "../../core/index.js";
 import { getOrCreate } from "../../util/index.js";
@@ -37,15 +37,20 @@ import { NodeKind } from "../core/index.js";
 export function toJsonSchema(schema: SimpleTreeSchema): JsonTreeSchema {
 	const definitions = convertDefinitions(schema.definitions);
 
-	const anyOf: JsonSchemaRef[] = [];
+	const allowedTypes: JsonSchemaRef[] = [];
 	for (const allowedType of schema.allowedTypes) {
-		anyOf.push(createSchemaRef(allowedType));
+		allowedTypes.push(createSchemaRef(allowedType));
 	}
 
-	return {
-		$defs: definitions,
-		anyOf,
-	};
+	return allowedTypes.length === 1
+		? {
+				...(allowedTypes[0] ?? oob()),
+				$defs: definitions,
+			}
+		: {
+				$defs: definitions,
+				anyOf: allowedTypes,
+			};
 }
 
 function convertDefinitions(
@@ -90,12 +95,14 @@ function convertArrayNodeSchema(schema: SimpleArrayNodeSchema): JsonArrayNodeSch
 	schema.allowedTypes.forEach((type) => {
 		allowedTypes.push(createSchemaRef(type));
 	});
+
+	const items: JsonFieldSchema =
+		allowedTypes.length === 1 ? allowedTypes[0] ?? oob() : { anyOf: allowedTypes };
+
 	return {
 		type: "array",
 		_treeNodeSchemaKind: NodeKind.Array,
-		items: {
-			anyOf: allowedTypes,
-		},
+		items,
 	};
 }
 
@@ -130,14 +137,17 @@ function convertObjectNodeSchema(schema: SimpleObjectNodeSchema): JsonObjectNode
 	const properties: Record<string, JsonFieldSchema> = {};
 	const required: string[] = [];
 	for (const [key, value] of Object.entries(schema.fields)) {
-		const anyOf: JsonSchemaRef[] = [];
+		const allowedTypes: JsonSchemaRef[] = [];
 		for (const allowedType of value.allowedTypes) {
-			anyOf.push(createSchemaRef(allowedType));
+			allowedTypes.push(createSchemaRef(allowedType));
 		}
 
-		properties[key] = {
-			anyOf,
-		};
+		properties[key] =
+			allowedTypes.length === 1
+				? allowedTypes[0] ?? oob()
+				: {
+						anyOf: allowedTypes,
+					};
 		if (value.kind === FieldKind.Required) {
 			required.push(key);
 		}
@@ -160,9 +170,12 @@ function convertMapNodeSchema(schema: SimpleMapNodeSchema): JsonMapNodeSchema {
 		type: "object",
 		_treeNodeSchemaKind: NodeKind.Map,
 		patternProperties: {
-			"^.*$": {
-				anyOf: allowedTypes,
-			},
+			"^.*$":
+				allowedTypes.length === 1
+					? allowedTypes[0] ?? oob()
+					: {
+							anyOf: allowedTypes,
+						},
 		},
 	};
 }

diff --git a/packages/dds/tree/src/test/simple-tree/api/simpleSchemaToJsonSchema.spec.ts b/packages/dds/tree/src/test/simple-tree/api/simpleSchemaToJsonSchema.spec.ts
@@ -33,11 +33,7 @@ describe("simpleSchemaToJsonSchema", () => {
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.string",
-				},
-			],
+			$ref: "#/$defs/test.string",
 		};
 		assert.deepEqual(actual, expected);
 
@@ -83,19 +79,15 @@ describe("simpleSchemaToJsonSchema", () => {
 					type: "array",
 					_treeNodeSchemaKind: NodeKind.Array,
 					items: {
-						anyOf: [{ $ref: "#/$defs/test.string" }],
+						$ref: "#/$defs/test.string",
 					},
 				},
 				"test.string": {
 					type: "string",
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.array",
-				},
-			],
+			$ref: "#/$defs/test.array",
 		};
 		assert.deepEqual(actual, expected);
 
@@ -128,19 +120,15 @@ describe("simpleSchemaToJsonSchema", () => {
 					type: "object",
 					_treeNodeSchemaKind: NodeKind.Map,
 					patternProperties: {
-						"^.*$": { anyOf: [{ $ref: "#/$defs/test.string" }] },
+						"^.*$": { $ref: "#/$defs/test.string" },
 					},
 				},
 				"test.string": {
 					type: "string",
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.map",
-				},
-			],
+			$ref: "#/$defs/test.map",
 		};
 		assert.deepEqual(actual, expected);
 
@@ -201,12 +189,8 @@ describe("simpleSchemaToJsonSchema", () => {
 					type: "object",
 					_treeNodeSchemaKind: NodeKind.Object,
 					properties: {
-						foo: {
-							anyOf: [{ $ref: "#/$defs/test.number" }],
-						},
-						bar: {
-							anyOf: [{ $ref: "#/$defs/test.string" }],
-						},
+						foo: { $ref: "#/$defs/test.number" },
+						bar: { $ref: "#/$defs/test.string" },
 					},
 					required: ["bar"],
 					additionalProperties: false,
@@ -220,11 +204,7 @@ describe("simpleSchemaToJsonSchema", () => {
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.object",
-				},
-			],
+			$ref: "#/$defs/test.object",
 		};
 		assert.deepEqual(actual, expected);
 
@@ -292,9 +272,7 @@ describe("simpleSchemaToJsonSchema", () => {
 					type: "object",
 					_treeNodeSchemaKind: NodeKind.Object,
 					properties: {
-						id: {
-							anyOf: [{ $ref: "#/$defs/test.identifier" }],
-						},
+						id: { $ref: "#/$defs/test.identifier" },
 					},
 					required: [],
 					additionalProperties: false,
@@ -304,11 +282,7 @@ describe("simpleSchemaToJsonSchema", () => {
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.object",
-				},
-			],
+			$ref: "#/$defs/test.object",
 		};
 		assert.deepEqual(actual, expected);
 	});
@@ -358,11 +332,7 @@ describe("simpleSchemaToJsonSchema", () => {
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.object",
-				},
-			],
+			$ref: "#/$defs/test.object",
 		};
 		assert.deepEqual(actual, expected);
 	});
@@ -409,11 +379,7 @@ describe("simpleSchemaToJsonSchema", () => {
 					_treeNodeSchemaKind: NodeKind.Leaf,
 				},
 			},
-			anyOf: [
-				{
-					$ref: "#/$defs/test.recursive-object",
-				},
-			],
+			$ref: "#/$defs/test.recursive-object",
 		};
 		assert.deepEqual(actual, expected);