refactor: centralise token header and url query keys

docs/README.md

@@ -28,6 +28,11 @@ graphql-sse
 - [StreamDataForID](README.md#streamdataforid)
 - [StreamEvent](README.md#streamevent)
 
+### Variables
+
+- [TOKEN\_HEADER\_KEY](README.md#token_header_key)
+- [TOKEN\_QUERY\_KEY](README.md#token_query_key)
+
 ### Functions
 
 - [createClient](README.md#createclient)
@@ -95,6 +100,28 @@ ___
 
 ___
 
+### TOKEN\_HEADER\_KEY
+
+• **TOKEN\_HEADER\_KEY**: ``"x-graphql-event-stream-token"``
+
+Header key through which the event stream token is transmitted
+when using the client in "single connection mode".
+
+Read more: https://github.com/enisdenjo/graphql-sse/blob/master/PROTOCOL.md#single-connection-mode
+
+___
+
+### TOKEN\_QUERY\_KEY
+
+• **TOKEN\_QUERY\_KEY**: ``"token"``
+
+URL query parameter key through which the event stream token is transmitted
+when using the client in "single connection mode".
+
+Read more: https://github.com/enisdenjo/graphql-sse/blob/master/PROTOCOL.md#single-connection-mode
+
+___
+
 ### parseStreamData
 
 ▸ **parseStreamData**(`e`, `data`): [`StreamData`](README.md#streamdata)

src/__tests__/handler.ts

@@ -4,6 +4,7 @@ import EventSource from 'eventsource';
 import { startTServer, startDisposableServer } from './utils/tserver';
 import { eventStream } from './utils/eventStream';
 import { createClient, createHandler } from '../index';
+import { TOKEN_HEADER_KEY, TOKEN_QUERY_KEY } from '../common';
 import http from 'http';
 import { schema } from './fixtures/simple';
 import fetch from 'node-fetch';
@@ -17,20 +18,20 @@ it('should only accept valid accept headers', async () => {
 
   let res = await request('GET', {
     accept: 'gibberish',
-    ['x-graphql-event-stream-token']: token,
+    [TOKEN_HEADER_KEY]: token,
   });
   expect(res.statusCode).toBe(406);
 
   res = await request('GET', {
     accept: 'application/graphql+json',
-    ['x-graphql-event-stream-token']: token,
+    [TOKEN_HEADER_KEY]: token,
   });
   expect(res.statusCode).toBe(400);
   expect(res.statusMessage).toBe('Missing query');
 
   res = await request('GET', {
     accept: 'application/json',
-    ['x-graphql-event-stream-token']: token,
+    [TOKEN_HEADER_KEY]: token,
   });
   expect(res.statusCode).toBe(400);
   expect(res.statusMessage).toBe('Missing query');
@@ -95,7 +96,7 @@ describe('single connection mode', () => {
     // token can be sent through the header
     let res = await request('PUT');
     es = new EventSource(url, {
-      headers: { ['x-graphql-event-stream-token']: res.data },
+      headers: { [TOKEN_HEADER_KEY]: res.data },
     });
     await new Promise<void>((resolve, reject) => {
       es.onopen = () => resolve();
@@ -108,7 +109,7 @@ describe('single connection mode', () => {
 
     // token can be sent through the url
     res = await request('PUT');
-    es = new EventSource(url + '?token=' + res.data);
+    es = new EventSource(url + '?' + TOKEN_QUERY_KEY + '=' + res.data);
     await new Promise<void>((resolve, reject) => {
       es.onopen = () => resolve();
       es.onerror = (e) => {
@@ -126,7 +127,7 @@ describe('single connection mode', () => {
 
     const { statusCode, statusMessage } = await request(
       'POST',
-      { 'x-graphql-event-stream-token': token },
+      { [TOKEN_HEADER_KEY]: token },
       { query: '{ getValue }' },
     );
 
@@ -139,7 +140,7 @@ describe('single connection mode', () => {
 
     const { data: token } = await request('PUT');
 
-    const es = new EventSource(url + '?token=' + token);
+    const es = new EventSource(url + '?' + TOKEN_QUERY_KEY + '=' + token);
     es.addEventListener('next', (event) => {
       expect((event as any).data).toMatchSnapshot();
     });
@@ -150,7 +151,7 @@ describe('single connection mode', () => {
 
     const { statusCode } = await request(
       'POST',
-      { 'x-graphql-event-stream-token': token },
+      { [TOKEN_HEADER_KEY]: token },
       { query: '{ getValue }', extensions: { operationId: '1' } },
     );
     expect(statusCode).toBe(202);
@@ -163,7 +164,7 @@ describe('single connection mode', () => {
 
     const { data: token } = await request('PUT');
 
-    const es = new EventSource(url + '?token=' + token);
+    const es = new EventSource(url + '?' + TOKEN_QUERY_KEY + '=' + token);
     es.addEventListener('next', (event) => {
       // called 5 times
       expect((event as any).data).toMatchSnapshot();
@@ -175,7 +176,7 @@ describe('single connection mode', () => {
 
     const { statusCode } = await request(
       'POST',
-      { 'x-graphql-event-stream-token': token },
+      { [TOKEN_HEADER_KEY]: token },
       { query: 'subscription { greetings }', extensions: { operationId: '1' } },
     );
     expect(statusCode).toBe(202);
@@ -186,7 +187,7 @@ describe('single connection mode', () => {
 
     const { data: token } = await request('PUT');
 
-    const es = new EventSource(url + '?token=' + token);
+    const es = new EventSource(url + '?' + TOKEN_QUERY_KEY + '=' + token);
     es.addEventListener('next', () => {
       fail('Shouldnt have omitted');
     });
@@ -196,7 +197,7 @@ describe('single connection mode', () => {
 
     const { statusCode, data } = await request(
       'POST',
-      { 'x-graphql-event-stream-token': token },
+      { [TOKEN_HEADER_KEY]: token },
       { query: '{ notExists }', extensions: { operationId: '1' } },
     );
     expect(statusCode).toBe(400);

src/client.ts

@@ -12,6 +12,7 @@ import {
   StreamMessage,
   ExecutionResult,
   ExecutionPatchResult,
+  TOKEN_HEADER_KEY,
 } from './common';
 
 /** This file is the entry point for browsers, re-export common elements. */
@@ -289,7 +290,7 @@ export function createClient(options: ClientOptions): Client {
           if (res.status !== 201) throw new NetworkError(res);
 
           const token = await res.text();
-          headers['x-graphql-event-stream-token'] = token;
+          headers[TOKEN_HEADER_KEY] = token;
 
           const connected = await connect({
             signal: connCtrl.signal,

src/common.ts

@@ -6,6 +6,26 @@
 
 import type { DocumentNode, GraphQLError } from 'graphql';
 
+/**
+ * Header key through which the event stream token is transmitted
+ * when using the client in "single connection mode".
+ *
+ * Read more: https://github.com/enisdenjo/graphql-sse/blob/master/PROTOCOL.md#single-connection-mode
+ *
+ * @category Common
+ */
+export const TOKEN_HEADER_KEY = 'x-graphql-event-stream-token' as const;
+
+/**
+ * URL query parameter key through which the event stream token is transmitted
+ * when using the client in "single connection mode".
+ *
+ * Read more: https://github.com/enisdenjo/graphql-sse/blob/master/PROTOCOL.md#single-connection-mode
+ *
+ * @category Common
+ */
+export const TOKEN_QUERY_KEY = 'token' as const;
+
 /**
  * Parameters for GraphQL's request for execution.
  *

src/handler.ts

@@ -23,6 +23,8 @@ import {
   StreamDataForID,
   ExecutionResult,
   ExecutionPatchResult,
+  TOKEN_HEADER_KEY,
+  TOKEN_QUERY_KEY,
 } from './common';
 
 /**
@@ -334,15 +336,14 @@ export function createHandler<
     subscribe = graphqlSubscribe,
     authenticate = function extractOrCreateStreamToken(req) {
       const headerToken =
-        req.headers['x-graphql-event-stream-token'] ||
-        req.headers['x-graphql-stream-token']; // @deprecated >v1.0.0
+        req.headers[TOKEN_HEADER_KEY] || req.headers['x-graphql-stream-token']; // @deprecated >v1.0.0
       if (headerToken)
         return Array.isArray(headerToken) ? headerToken.join('') : headerToken;
 
       const urlToken = new URL(
         req.url ?? '',
         'http://localhost/',
-      ).searchParams.get('token');
+      ).searchParams.get(TOKEN_QUERY_KEY);
       if (urlToken) return urlToken;
 
       return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {