[Float] support all links as Resources (#25515)

stacked on #25514

This PR adds support for any type of Link as long as it has a string rel
and href and does not include an onLoad or onError property.

The semantics for generic link resources matches other head resources,
they will be inserted and removed as their ref counts go positive and
back to zero.

Keys are based on rel, href, sizes, and media.

on the server preconnect and prefetch-dns are privileged and will emit
near the start of the stream.

packages/react-dom-bindings/src/client/ReactDOMFloatClient.js

@@ -13,7 +13,7 @@ import ReactDOMSharedInternals from 'shared/ReactDOMSharedInternals.js';
 const {Dispatcher} = ReactDOMSharedInternals;
 import {DOCUMENT_NODE} from '../shared/HTMLNodeType';
 import {
-  validateUnmatchedLinkResourceProps,
+  warnOnMissingHrefAndRel,
   validatePreloadResourceDifference,
   validateURLKeyedUpdatedProps,
   validateStyleResourceDifference,
@@ -54,7 +54,7 @@ type StyleProps = {
   'data-precedence': string,
   [string]: mixed,
 };
-export type StyleResource = {
+type StyleResource = {
   type: 'style',
 
   // Ref count for resource
@@ -79,7 +79,7 @@ type ScriptProps = {
   src: string,
   [string]: mixed,
 };
-export type ScriptResource = {
+type ScriptResource = {
   type: 'script',
   src: string,
   props: ScriptProps,
@@ -88,12 +88,10 @@ export type ScriptResource = {
   root: FloatRoot,
 };
 
-export type HeadResource = TitleResource | MetaResource;
-
 type TitleProps = {
   [string]: mixed,
 };
-export type TitleResource = {
+type TitleResource = {
   type: 'title',
   props: TitleProps,
 
@@ -105,7 +103,7 @@ export type TitleResource = {
 type MetaProps = {
   [string]: mixed,
 };
-export type MetaResource = {
+type MetaResource = {
   type: 'meta',
   matcher: string,
   property: ?string,
@@ -117,8 +115,23 @@ export type MetaResource = {
   root: Document,
 };
 
+type LinkProps = {
+  href: string,
+  rel: string,
+  [string]: mixed,
+};
+type LinkResource = {
+  type: 'link',
+  props: LinkProps,
+
+  count: number,
+  instance: ?Element,
+  root: Document,
+};
+
 type Props = {[string]: mixed};
 
+type HeadResource = TitleResource | MetaResource | LinkResource;
 type Resource = StyleResource | ScriptResource | PreloadResource | HeadResource;
 
 export type RootResources = {
@@ -617,8 +630,30 @@ export function getResource(
           return null;
         }
         default: {
+          const {href, sizes, media} = pendingProps;
+          if (typeof rel === 'string' && typeof href === 'string') {
+            const sizeKey =
+              '::sizes:' + (typeof sizes === 'string' ? sizes : '');
+            const mediaKey =
+              '::media:' + (typeof media === 'string' ? media : '');
+            const key = 'rel:' + rel + '::href:' + href + sizeKey + mediaKey;
+            const headRoot = getDocumentFromRoot(resourceRoot);
+            const headResources = getResourcesFromRoot(headRoot).head;
+            let resource = headResources.get(key);
+            if (!resource) {
+              resource = {
+                type: 'link',
+                props: Object.assign({}, pendingProps),
+                count: 0,
+                instance: null,
+                root: headRoot,
+              };
+              headResources.set(key, resource);
+            }
+            return resource;
+          }
           if (__DEV__) {
-            validateUnmatchedLinkResourceProps(pendingProps, currentProps);
+            warnOnMissingHrefAndRel(pendingProps, currentProps);
           }
           return null;
         }
@@ -710,6 +745,7 @@ function scriptPropsFromRawProps(rawProps: ScriptQualifyingProps): ScriptProps {
 export function acquireResource(resource: Resource): Instance {
   switch (resource.type) {
     case 'title':
+    case 'link':
     case 'meta': {
       return acquireHeadResource(resource);
     }
@@ -732,6 +768,7 @@ export function acquireResource(resource: Resource): Instance {
 
 export function releaseResource(resource: Resource): void {
   switch (resource.type) {
+    case 'link':
     case 'title':
     case 'meta': {
       return releaseHeadResource(resource);
@@ -1050,6 +1087,41 @@ function acquireHeadResource(resource: HeadResource): Instance {
         insertResourceInstanceBefore(root, instance, insertBefore);
         break;
       }
+      case 'link': {
+        const linkProps: LinkProps = (props: any);
+        const limitedEscapedRel = escapeSelectorAttributeValueInsideDoubleQuotes(
+          linkProps.rel,
+        );
+        const limitedEscapedHref = escapeSelectorAttributeValueInsideDoubleQuotes(
+          linkProps.href,
+        );
+        let selector = `link[rel="${limitedEscapedRel}"][href="${limitedEscapedHref}"]`;
+        if (typeof linkProps.sizes === 'string') {
+          const limitedEscapedSizes = escapeSelectorAttributeValueInsideDoubleQuotes(
+            linkProps.sizes,
+          );
+          selector += `[sizes="${limitedEscapedSizes}"]`;
+        }
+        if (typeof linkProps.media === 'string') {
+          const limitedEscapedMedia = escapeSelectorAttributeValueInsideDoubleQuotes(
+            linkProps.media,
+          );
+          selector += `[media="${limitedEscapedMedia}"]`;
+        }
+        const existingEl = root.querySelector(selector);
+        if (existingEl) {
+          instance = resource.instance = existingEl;
+          markNodeAsResource(instance);
+          return instance;
+        }
+        instance = resource.instance = createResourceInstance(
+          type,
+          props,
+          root,
+        );
+        insertResourceInstanceBefore(root, instance, null);
+        return instance;
+      }
       default: {
         throw new Error(
           `acquireHeadResource encountered a resource type it did not expect: "${type}". This is a bug in React.`,
@@ -1265,26 +1337,27 @@ export function isHostResourceType(type: string, props: Props): boolean {
       return true;
     }
     case 'link': {
+      const {onLoad, onError} = props;
+      if (onLoad || onError) {
+        return false;
+      }
       switch (props.rel) {
         case 'stylesheet': {
           if (__DEV__) {
             validateLinkPropsForStyleResource(props);
           }
-          const {href, precedence, onLoad, onError, disabled} = props;
+          const {href, precedence, disabled} = props;
           return (
             typeof href === 'string' &&
             typeof precedence === 'string' &&
-            !onLoad &&
-            !onError &&
             disabled == null
           );
         }
-        case 'preload': {
-          const {href, onLoad, onError} = props;
-          return !onLoad && !onError && typeof href === 'string';
+        default: {
+          const {rel, href} = props;
+          return typeof href === 'string' && typeof rel === 'string';
         }
       }
-      return false;
     }
     case 'script': {
       // We don't validate because it is valid to use async with onLoad/onError unlike combining

packages/react-dom-bindings/src/server/ReactDOMFloatServer.js

@@ -89,8 +89,20 @@ type MetaResource = {
   flushed: boolean,
 };
 
+type LinkProps = {
+  href: string,
+  rel: string,
+  [string]: mixed,
+};
+type LinkResource = {
+  type: 'link',
+  props: LinkProps,
+
+  flushed: boolean,
+};
+
 export type Resource = PreloadResource | StyleResource | ScriptResource;
-export type HeadResource = TitleResource | MetaResource;
+export type HeadResource = TitleResource | MetaResource | LinkResource;
 
 export type Resources = {
   // Request local cache
@@ -101,6 +113,7 @@ export type Resources = {
 
   // Flushing queues for Resource dependencies
   charset: null | MetaResource,
+  preconnects: Set<LinkResource>,
   fontPreloads: Set<PreloadResource>,
   // usedImagePreloads: Set<PreloadResource>,
   precedences: Map<string, Set<StyleResource>>,
@@ -131,6 +144,7 @@ export function createResources(): Resources {
 
     // cleared on flush
     charset: null,
+    preconnects: new Set(),
     fontPreloads: new Set(),
     // usedImagePreloads: new Set(),
     precedences: new Map(),
@@ -697,10 +711,11 @@ export function resourcesFromLink(props: Props): boolean {
   const resources = currentResources;
 
   const {rel, href} = props;
-  if (!href || typeof href !== 'string') {
+  if (!href || typeof href !== 'string' || !rel || typeof rel !== 'string') {
     return false;
   }
 
+  let key = '';
   switch (rel) {
     case 'stylesheet': {
       const {onLoad, onError, precedence, disabled} = props;
@@ -813,10 +828,37 @@ export function resourcesFromLink(props: Props): boolean {
           return true;
         }
       }
-      return false;
+      break;
     }
   }
-  return false;
+  if (props.onLoad || props.onError) {
+    return false;
+  }
+
+  const sizes = typeof props.sizes === 'string' ? props.sizes : '';
+  const media = typeof props.media === 'string' ? props.media : '';
+  key =
+    'rel:' + rel + '::href:' + href + '::sizes:' + sizes + '::media:' + media;
+  let resource = resources.headsMap.get(key);
+  if (!resource) {
+    resource = {
+      type: 'link',
+      props: Object.assign({}, props),
+      flushed: false,
+    };
+    resources.headsMap.set(key, resource);
+    switch (rel) {
+      case 'preconnect':
+      case 'dns-prefetch': {
+        resources.preconnects.add(resource);
+        break;
+      }
+      default: {
+        resources.headResources.add(resource);
+      }
+    }
+  }
+  return true;
 }
 
 // Construct a resource from link props.

packages/react-dom-bindings/src/server/ReactDOMServerFormatConfig.js

@@ -2340,6 +2340,7 @@ export function writeInitialResources(
 
   const {
     charset,
+    preconnects,
     fontPreloads,
     precedences,
     usedStylePreloads,
@@ -2356,6 +2357,13 @@ export function writeInitialResources(
     resources.charset = null;
   }
 
+  preconnects.forEach(r => {
+    // font preload Resources should not already be flushed so we elide this check
+    pushLinkImpl(target, r.props, responseState);
+    r.flushed = true;
+  });
+  preconnects.clear();
+
   fontPreloads.forEach(r => {
     // font preload Resources should not already be flushed so we elide this check
     pushLinkImpl(target, r.props, responseState);
@@ -2418,6 +2426,10 @@ export function writeInitialResources(
         pushSelfClosing(target, r.props, 'meta', responseState);
         break;
       }
+      case 'link': {
+        pushLinkImpl(target, r.props, responseState);
+        break;
+      }
     }
     r.flushed = true;
   });
@@ -2450,6 +2462,7 @@ export function writeImmediateResources(
 
   const {
     charset,
+    preconnects,
     fontPreloads,
     usedStylePreloads,
     scripts,
@@ -2465,6 +2478,13 @@ export function writeImmediateResources(
     resources.charset = null;
   }
 
+  preconnects.forEach(r => {
+    // font preload Resources should not already be flushed so we elide this check
+    pushLinkImpl(target, r.props, responseState);
+    r.flushed = true;
+  });
+  preconnects.clear();
+
   fontPreloads.forEach(r => {
     // font preload Resources should not already be flushed so we elide this check
     pushLinkImpl(target, r.props, responseState);
@@ -2507,6 +2527,10 @@ export function writeImmediateResources(
         pushSelfClosing(target, r.props, 'meta', responseState);
         break;
       }
+      case 'link': {
+        pushLinkImpl(target, r.props, responseState);
+        break;
+      }
     }
     r.flushed = true;
   });