Merge pull request openedx#3 from edx/djoy/shoulders_of_giants

Absorbing work from douglashall/learning_sequence

.env.development

@@ -1,7 +1,7 @@
 NODE_ENV='development'
-PORT=8080
+PORT=2000
 ACCESS_TOKEN_COOKIE_NAME='edx-jwt-cookie-header-payload'
-BASE_URL='localhost:8080'
+BASE_URL='localhost:2000'
 CREDENTIALS_BASE_URL='http://localhost:18150'
 CSRF_TOKEN_API_PATH='/csrf/api/v1/token'
 ECOMMERCE_BASE_URL='http://localhost:18130'

src/index.jsx

@@ -4,12 +4,13 @@ import { APP_INIT_ERROR, APP_READY, subscribe, initialize } from '@edx/frontend-
 import { AppProvider, ErrorPage } from '@edx/frontend-platform/react';
 import React from 'react';
 import ReactDOM from 'react-dom';
+import { Route, Switch, Link } from 'react-router-dom';
 
 import Header, { messages as headerMessages } from '@edx/frontend-component-header';
 import Footer, { messages as footerMessages } from '@edx/frontend-component-footer';
 
 import appMessages from './i18n';
-import ExamplePage from './example/ExamplePage';
+import LearningSequencePage from './learning-sequence/LearningSequencePage';
 
 import './index.scss';
 import './assets/favicon.ico';
@@ -18,7 +19,14 @@ subscribe(APP_READY, () => {
   ReactDOM.render(
     <AppProvider>
       <Header />
-      <ExamplePage />
+      <Switch>
+        <Route
+          exact
+          path="/"
+          render={() => <Link to="/course/course-v1%3AedX%2BDemoX%2BDemo_Course/0">Visit Demo Course</Link>}
+        />
+        <Route path="/course/:courseId/:blockIndex" component={LearningSequencePage} />
+      </Switch>
       <Footer />
     </AppProvider>,
     document.getElementById('root'),

src/index.scss

@@ -1,6 +1,6 @@
 @import '~@edx/paragon/scss/edx/theme.scss';
 
-@import './example/index.scss';
+@import './learning-sequence/index';
 
 @import "~@edx/frontend-component-header/dist/index";
 @import "~@edx/frontend-component-footer/dist/footer";

src/learning-sequence/LearningSequencePage.jsx

@@ -0,0 +1,116 @@
+import React, { useState, useEffect, useCallback, useRef } from 'react';
+import PropTypes from 'prop-types';
+import { camelCaseObject, getConfig } from '@edx/frontend-platform';
+import { getAuthenticatedHttpClient } from '@edx/frontend-platform/auth';
+import { injectIntl, intlShape } from '@edx/frontend-platform/i18n';
+
+import PageLoading from './PageLoading';
+
+import messages from './messages';
+
+function useApi(apiFunction, {
+  format = true, keepDataIfFailed = false, loadedIfFailed = false, refreshParams = [],
+}) {
+  const [data, setData] = useState(null);
+  const [loading, setLoading] = useState(false);
+  const [loaded, setLoaded] = useState(false);
+  const [failed, setFailed] = useState(false);
+  const [error, setError] = useState(null);
+
+  useEffect(() => {
+    setLoading(true);
+    apiFunction().then((response) => {
+      const result = format ? camelCaseObject(response.data) : response.data;
+      setData(result);
+      setLoaded(true);
+      setLoading(false);
+      setError(null);
+      setFailed(false);
+    })
+      .catch((e) => {
+        if (keepDataIfFailed) {
+          setData(null);
+        }
+        setFailed(true);
+        setLoading(false);
+        if (loadedIfFailed) {
+          setLoaded(true);
+        }
+        setError(e);
+      });
+  }, refreshParams);
+
+  return {
+    data,
+    loading,
+    loaded,
+    failed,
+    error,
+  };
+}
+
+function LearningSequencePage(props) {
+  const iframeRef = useRef(null);
+
+  const handleResizeIframe = useCallback(() => {
+    // TODO: This won't work because of crossdomain issues.  Leaving here for reference once we're
+    // able to have the iFrame content publish resize events through postMessage
+    console.log('**** Resizing iframe...');
+    const iframe = iframeRef.current;
+    const contentHeight = iframe.contentWindow.document.body.scrollHeight;
+    console.log(`**** Height is: ${contentHeight}`);
+    iframe.height = contentHeight + 20;
+  });
+
+  const {
+    data,
+    loading,
+    loaded,
+  } = useApi(
+    async () => getAuthenticatedHttpClient().get(`${getConfig().LMS_BASE_URL}/api/courses/v1/blocks/?course_id=${props.match.params.courseId}&username=staff&depth=all&block_types_filter=sequential&requested_fields=children`, {}),
+    {
+      keepDataIfFailed: false,
+      refreshParams: [
+        props.match.params.courseId,
+        props.match.params.blockIndex,
+      ],
+    },
+  );
+
+  console.log(data);
+
+  if (loading) {
+    return (
+      <PageLoading srMessage={props.intl.formatMessage(messages['learn.loading.learning.sequence'])} />
+    );
+  }
+
+  return (
+    <main>
+      <div className="container-fluid">
+        <h1>Learning Sequence Page</h1>
+        {loaded && data.blocks ? (
+          <iframe
+            title="yus"
+            ref={iframeRef}
+            src={Object.values(data.blocks)[parseInt(props.match.params.blockIndex, 10)].studentViewUrl}
+            onLoad={handleResizeIframe}
+            height={500}
+          />
+        ) : null}
+      </div>
+    </main>
+  );
+}
+
+LearningSequencePage.propTypes = {
+  match: PropTypes.shape({
+    params: PropTypes.shape({
+      courseId: PropTypes.string.isRequired,
+      blockIndex: PropTypes.number.isRequired,
+    }).isRequired,
+  }).isRequired,
+  intl: intlShape.isRequired,
+};
+
+export default injectIntl(LearningSequencePage);

src/learning-sequence/PageLoading.jsx

@@ -0,0 +1,37 @@
+import React, { Component } from 'react';
+import PropTypes from 'prop-types';
+
+export default class PageLoading extends Component {
+  renderSrMessage() {
+    if (!this.props.srMessage) {
+      return null;
+    }
+
+    return (
+      <span className="sr-only">
+        {this.props.srMessage}
+      </span>
+    );
+  }
+
+  render() {
+    return (
+      <div>
+        <div
+          className="d-flex justify-content-center align-items-center flex-column"
+          style={{
+            height: '50vh',
+          }}
+        >
+          <div className="spinner-border text-primary" role="status">
+            {this.renderSrMessage()}
+          </div>
+        </div>
+      </div>
+    );
+  }
+}
+
+PageLoading.propTypes = {
+  srMessage: PropTypes.string.isRequired,
+};

src/learning-sequence/index.scss

@@ -0,0 +1,4 @@
+iframe {
+  border: 0;
+  width: 100%;
+}

src/learning-sequence/messages.js

@@ -0,0 +1,16 @@
+import { defineMessages } from '@edx/frontend-platform/i18n';
+
+const messages = defineMessages({
+  'learn.loading.learning.sequence': {
+    id: 'learn.loading.learning.sequence',
+    defaultMessage: 'Loading learning sequence...',
+    description: 'Message when learning sequence is being loaded',
+  },
+  'learn.loading.error': {
+    id: 'learn.loading.error',
+    defaultMessage: 'Error: {error}',
+    description: 'Message when learning sequence fails to load',
+  },
+});
+
+export default messages;