feat: Add support for persisted documents via the documentId property

.changeset/two-bananas-grow.md

@@ -0,0 +1,5 @@
+---
+'@urql/core': minor
+---
+
+Add support for sending persisted documents. Any `DocumentNode` with no/empty definitions and a `documentId` property is considered a persisted document. When this is detected a `documentId` parameter rather than a `query` string is sent to the GraphQL API, similar to Automatic Persisted Queries (APQs). However, APQs are only supported via `@urql/exchange-persisted`, while support for `documentId` is now built-in.

packages/core/src/internal/fetchOptions.test.ts

@@ -1,6 +1,7 @@
 // @vitest-environment jsdom
 
 import { expect, describe, it } from 'vitest';
+import { Kind } from '@0no-co/graphql.web';
 import { makeOperation } from '../utils/operation';
 import { queryOperation, mutationOperation } from '../test-utils';
 import { makeFetchBody, makeFetchURL, makeFetchOptions } from './fetchOptions';
@@ -10,6 +11,7 @@ describe('makeFetchBody', () => {
     const body = makeFetchBody(queryOperation);
     expect(body).toMatchInlineSnapshot(`
       {
+        "documentId": undefined,
         "extensions": undefined,
         "operationName": "getUser",
         "query": "query getUser($name: String) {
@@ -42,6 +44,22 @@ describe('makeFetchBody', () => {
     apqOperation.extensions.persistedQuery!.miss = true;
     expect(makeFetchBody(apqOperation).query).not.toBe(undefined);
   });
+
+  it('omits the query property when query is a persisted document', () => {
+    // A persisted documents is one that carries a `documentId` property and
+    // has no definitions
+    const persistedOperation = makeOperation(queryOperation.kind, {
+      ...queryOperation,
+      query: {
+        kind: Kind.DOCUMENT,
+        definitions: [],
+        documentId: 'TestDocumentId',
+      },
+    });
+
+    expect(makeFetchBody(persistedOperation).query).toBe(undefined);
+    expect(makeFetchBody(persistedOperation).documentId).toBe('TestDocumentId');
+  });
 });
 
 describe('makeFetchURL', () => {

packages/core/src/internal/fetchOptions.ts

@@ -10,6 +10,7 @@ import type { AnyVariables, GraphQLRequest, Operation } from '../types';
 /** Abstract definition of the JSON data sent during GraphQL HTTP POST requests. */
 export interface FetchBody {
   query?: string;
+  documentId?: string;
   operationName: string | undefined;
   variables: undefined | Record<string, any>;
   extensions: undefined | Record<string, any>;
@@ -24,16 +25,31 @@ export function makeFetchBody<
   Data = any,
   Variables extends AnyVariables = AnyVariables,
 >(request: Omit<GraphQLRequest<Data, Variables>, 'key'>): FetchBody {
-  const isAPQ =
-    request.extensions &&
-    request.extensions.persistedQuery &&
-    !request.extensions.persistedQuery.miss;
-  return {
-    query: isAPQ ? undefined : stringifyDocument(request.query),
+  const body: FetchBody = {
+    query: undefined,
+    documentId: undefined,
     operationName: getOperationName(request.query),
     variables: request.variables || undefined,
     extensions: request.extensions,
   };
+
+  if (
+    'documentId' in request.query &&
+    request.query.documentId &&
+    // NOTE: We have to check that the document will definitely be sent
+    // as a persisted document to avoid breaking changes
+    (!request.query.definitions || !request.query.definitions.length)
+  ) {
+    body.documentId = request.query.documentId;
+  } else if (
+    !request.extensions ||
+    !request.extensions.persistedQuery ||
+    !!request.extensions.persistedQuery.miss
+  ) {
+    body.query = stringifyDocument(request.query);
+  }
+
+  return body;
 }
 
 /** Creates a URL that will be called for a GraphQL HTTP request.

packages/core/src/types.ts

@@ -9,6 +9,11 @@ import type { Subscription, Source } from 'wonka';
 import type { Client } from './client';
 import type { CombinedError } from './utils/error';
 
+/** A GraphQL persisted document will contain `documentId` that replaces its definitions */
+export interface PersistedDocument extends DocumentNode {
+  documentId?: string;
+}
+
 /** A GraphQL `DocumentNode` with attached generics for its result data and variables.
  *
  * @remarks
@@ -340,7 +345,7 @@ export interface GraphQLRequest<
    * In `urql`, we expect a document to only contain a single operation that is executed rather than
    * multiple ones by convention.
    */
-  query: DocumentNode | TypedDocumentNode<Data, Variables>;
+  query: DocumentNode | PersistedDocument | TypedDocumentNode<Data, Variables>;
   /** Variables used to execute the `query` document.
    *
    * @remarks