Implement options and scrollYOffset option

demo/playground/hmr-playground.tsx

@@ -3,11 +3,11 @@ import { render } from 'react-dom';
 import { AppContainer } from 'react-hot-loader';
 // import DevTools from 'mobx-react-devtools';
 
-import { Redoc } from '../../src/components/Redoc/Redoc';
+import { Redoc, RedocProps } from '../../src/components/Redoc/Redoc';
 import { AppStore } from '../../src/services/AppStore';
 import { loadAndBundleSpec } from '../../src/utils/loadAndBundleSpec';
 
-const renderRoot = (Component: typeof Redoc, props: { store: AppStore }) =>
+const renderRoot = (Component: typeof Redoc, props: RedocProps) =>
   render(
     <div>
       <AppContainer>
@@ -23,11 +23,12 @@ const swagger = window.location.search.indexOf('swagger') > -1; //compatibility
 const specUrl = swagger ? 'swagger.yaml' : big ? 'big-openapi.json' : 'openapi.yaml';
 
 let store;
+const options = {};
 
 async function init() {
   const spec = await loadAndBundleSpec(specUrl);
   store = new AppStore(spec, specUrl);
-  renderRoot(Redoc, { store: store });
+  renderRoot(Redoc, { store: store, options });
 }
 
 init();
@@ -42,7 +43,7 @@ if (module.hot) {
       store = AppStore.fromJS(state);
     }
 
-    renderRoot(Redoc, { store: store });
+    renderRoot(Redoc, { store: store, options });
   };
 
   module.hot.accept(['../../src/components/Redoc/Redoc'], reload());

package.json

@@ -69,6 +69,7 @@
     "webpack-node-externals": "^1.6.0"
   },
   "dependencies": {
+    "@types/prop-types": "^15.5.2",
     "decko": "^1.2.0",
     "eventemitter3": "^2.0.3",
     "json-pointer": "^0.6.0",
@@ -77,6 +78,7 @@
     "mobx-react": "^4.3.3",
     "openapi-sampler": "^1.0.0-beta.1",
     "prismjs": "^1.8.1",
+    "prop-types": "^15.6.0",
     "react": "^16.0.0",
     "react-dom": "^16.0.0",
     "react-dropdown": "^1.3.0",

src/components/OptionsProvider.ts

@@ -0,0 +1,40 @@
+import * as React from 'react';
+import * as PropTypes from 'prop-types';
+
+import { RedocNormalizedOptions } from '../services/RedocNormalizedOptions';
+import { ThemeInterface } from '../theme';
+
+export interface RedocRawOptions {
+  theme?: ThemeInterface;
+  scrollYOffset?: number | string | Function;
+}
+
+export interface OptionsProviderProps {
+  options: RedocRawOptions;
+}
+
+export class OptionsProvider extends React.Component<OptionsProviderProps> {
+  static childContextTypes = {
+    redocOptions: PropTypes.object.isRequired,
+  };
+
+  getChildContext() {
+    return {
+      redocOptions: new RedocNormalizedOptions(this.props.options),
+    };
+  }
+
+  render() {
+    return React.Children.only(this.props.children);
+  }
+}
+
+export class ComponentWithOptions<P = {}, S = {}> extends React.Component<P, S> {
+  static contextTypes = {
+    redocOptions: PropTypes.object,
+  };
+
+  get options(): RedocNormalizedOptions {
+    return this.context.redocOptions || {};
+  }
+}

src/components/Redoc/Redoc.tsx

@@ -1,56 +1,50 @@
 import * as React from 'react';
-import Stickyfill from 'stickyfill';
+import * as PropTypes from 'prop-types';
 
 import { ThemeProvider } from '../../styled-components';
 
 import { ApiInfo } from '../ApiInfo/ApiInfo';
-import { RedocWrap, StickySidebar, ApiContent } from './elements';
+import { RedocWrap, ApiContent } from './elements';
 import { ApiLogo } from '../ApiLogo/ApiLogo';
 import { SideMenu } from '../SideMenu/SideMenu';
 import { ContentItems } from '../ContentItems/ContentItems';
 import { AppStore } from '../../services';
+import { OptionsProvider, RedocRawOptions } from '../OptionsProvider';
+import { StickySidebar } from '../StickySidebar/StickySidebar';
 
-import defaultTheme, { ThemeInterface } from '../../theme';
+import defaultTheme from '../../theme';
 
 export interface RedocProps {
   store: AppStore;
-  options?: {
-    theme?: ThemeInterface;
-  };
+  options?: RedocRawOptions;
 }
 
-const stickyfill = Stickyfill();
 export class Redoc extends React.Component<RedocProps> {
-  stickyElement: Element;
+  static propTypes = {
+    store: PropTypes.instanceOf(AppStore).isRequired,
+    options: PropTypes.object,
+  };
 
   componentDidMount() {
     this.props.store.menu.updateOnHash();
-    stickyfill.add(this.stickyElement);
-  }
-
-  componentWillUnmount() {
-    stickyfill.remove(this.stickyElement);
   }
 
   render() {
     const { store: { spec, menu }, options = {} } = this.props;
     return (
       <ThemeProvider theme={{ ...options.theme, ...defaultTheme }}>
-        <RedocWrap className="redoc-wrap">
-          <StickySidebar
-            className="menu-content"
-            innerRef={el => {
-              this.stickyElement = el;
-            }}
-          >
-            <ApiLogo info={spec.info} />
-            <SideMenu menu={menu} />
-          </StickySidebar>
-          <ApiContent className="api-content">
-            <ApiInfo info={spec.info} externalDocs={spec.externalDocs} />
-            <ContentItems items={menu.items as any} />
-          </ApiContent>
-        </RedocWrap>
+        <OptionsProvider options={options}>
+          <RedocWrap className="redoc-wrap">
+            <StickySidebar className="menu-content">
+              <ApiLogo info={spec.info} />
+              <SideMenu menu={menu} />
+            </StickySidebar>
+            <ApiContent className="api-content">
+              <ApiInfo info={spec.info} externalDocs={spec.externalDocs} />
+              <ContentItems items={menu.items as any} />
+            </ApiContent>
+          </RedocWrap>
+        </OptionsProvider>
       </ThemeProvider>
     );
   }

src/components/Redoc/elements.tsx

@@ -33,21 +33,6 @@ export const RedocWrap = styled.div`
   }
 `;
 
-export const StickySidebar = styled.div`
-  width: ${props => props.theme.menu.width};
-  background-color: ${props => props.theme.menu.backgroundColor};
-  overflow: hidden;
-  display: flex;
-  flex-direction: column;
-
-  transform: translateZ(0);
-
-  height: 100vh;
-  position: sticky;
-  position: -webkit-sticky;
-  top: 0;
-`;
-
 export const ApiContent = styled.div`
   z-index: 10;
   position: relative;

src/components/StickySidebar/StickySidebar.tsx

@@ -0,0 +1,68 @@
+import * as React from 'react';
+import Stickyfill from 'stickyfill';
+
+import { ComponentWithOptions, RedocRawOptions } from '../OptionsProvider';
+import { RedocNormalizedOptions } from '../../services/RedocNormalizedOptions';
+import styled from '../../styled-components';
+
+export interface StickySidebarProps {
+  className?: string;
+  scrollYOffset?: RedocRawOptions['scrollYOffset']; // passed directly or via context
+}
+
+const stickyfill = Stickyfill();
+
+const StyledStickySidebar = styled.div`
+  width: ${props => props.theme.menu.width};
+  background-color: ${props => props.theme.menu.backgroundColor};
+  overflow: hidden;
+  display: flex;
+  flex-direction: column;
+
+  transform: translateZ(0);
+
+  height: 100vh;
+  position: sticky;
+  position: -webkit-sticky;
+  top: 0;
+`;
+
+export class StickySidebar extends ComponentWithOptions<StickySidebarProps> {
+  stickyElement: Element;
+
+  componentDidMount() {
+    stickyfill.add(this.refs['sticky-children']);
+  }
+
+  componentWillUnmount() {
+    stickyfill.remove(this.refs['sticky-children']);
+  }
+
+  get scrollYOffset() {
+    let top;
+    if (this.props.scrollYOffset !== undefined) {
+      top = RedocNormalizedOptions.normalizeScrollYOffset(this.props.scrollYOffset)();
+    } else {
+      top = this.options.scrollYOffset();
+    }
+    return top + 'px';
+  }
+
+  render() {
+    let top = this.scrollYOffset;
+
+    const height = `calc(100vh - ${top})`;
+
+    return (
+      <StyledStickySidebar
+        className={this.props.className}
+        style={{ top, height }}
+        innerRef={el => {
+          this.stickyElement = el;
+        }}
+      >
+        {this.props.children}
+      </StyledStickySidebar>
+    );
+  }
+}

src/components/StoreProvider.ts

@@ -1,4 +1,5 @@
 import { Component } from 'react';
+
 import { AppStore } from '../services/';
 import { loadAndBundleSpec } from '../utils';
 

src/services/RedocNormalizedOptions.ts

@@ -0,0 +1,44 @@
+import { RedocRawOptions } from '../components/OptionsProvider';
+import { ThemeInterface } from '../theme';
+import { isNumeric } from '../utils/helpers';
+
+export class RedocNormalizedOptions {
+  theme: ThemeInterface;
+  scrollYOffset: () => number;
+
+  constructor(raw: RedocRawOptions) {
+    this.scrollYOffset = RedocNormalizedOptions.normalizeScrollYOffset(raw.scrollYOffset);
+  }
+
+  static normalizeScrollYOffset(value: RedocRawOptions['scrollYOffset']): () => number {
+    // just number is not valid selector and leads to crash so checking if isNumeric here
+    if (typeof value === 'string' && !isNumeric(value)) {
+      const el = document.querySelector(value);
+      if (!el) {
+        console.warn(
+          'scrollYOffset value is a selector to non-existing element. Using offset 0 by default',
+        );
+      }
+      const bottom = (el && el.getBoundingClientRect().bottom) || 0;
+      return () => bottom;
+    } else if (typeof value === 'number' || isNumeric(value)) {
+      return () => (typeof value === 'number' ? value : parseFloat(value));
+    } else if (typeof value === 'function') {
+      return () => {
+        const res = value();
+        if (typeof res !== 'number') {
+          console.warn(
+            `scrollYOffset should return number but returned value "${res}" of type ${typeof res}`,
+          );
+        }
+        return res;
+      };
+    } else if (value !== undefined) {
+      console.warn(
+        'Wrong value for scrollYOffset ReDoc option: should be string, number or function',
+      );
+    }
+
+    return () => 0;
+  }
+}

src/utils/helpers.ts

@@ -63,3 +63,7 @@ export function stripTrailingSlash(path: string): string {
 export function isAbsolutePath(path: string): boolean {
   return /^(?:[a-z]+:)?/i.test(path);
 }
+
+export function isNumeric(n: any): n is Number {
+  return !isNaN(parseFloat(n)) && isFinite(n);
+}

yarn.lock

@@ -67,6 +67,10 @@
   version "1.6.5"
   resolved "https://registry.yarnpkg.com/@types/prismjs/-/prismjs-1.6.5.tgz#e222615538ea2df248c72512e1faf346af2640d6"
 
+"@types/prop-types@^15.5.2":
+  version "15.5.2"
+  resolved "https://registry.yarnpkg.com/@types/prop-types/-/prop-types-15.5.2.tgz#3c6b8dceb2906cc87fe4358e809f9d20c8d59be1"
+
 "@types/react-dom@^16.0.0":
   version "16.0.3"
   resolved "https://registry.yarnpkg.com/@types/react-dom/-/react-dom-16.0.3.tgz#8accad7eabdab4cca3e1a56f5ccb57de2da0ff64"