Refactor containers to share more code (#61)

Specifically, make sure that the header, footer, and tabs are all
shared code so that they look the same and don't need to be
redefined as we add more tab pages.

src/data/api.js

@@ -3,6 +3,20 @@ import { getConfig, camelCaseObject } from '@edx/frontend-platform';
 import { getAuthenticatedHttpClient, getAuthenticatedUser } from '@edx/frontend-platform/auth';
 import { logError } from '@edx/frontend-platform/logging';
 
+function overrideTabUrls(id, tabs) {
+  // "LMS tab slug" to "MFE URL slug" for overridden tabs
+  const tabOverrides = {};
+  return tabs.map((tab) => {
+    let url;
+    if (tabOverrides[tab.slug]) {
+      url = `/course/${id}/${tabOverrides[tab.slug]}`;
+    } else {
+      url = `${getConfig().LMS_BASE_URL}${tab.url}`;
+    }
+    return { ...tab, url };
+  });
+}
+
 function normalizeMetadata(metadata) {
   return {
     canShowUpgradeSock: metadata.can_show_upgrade_sock,
@@ -23,7 +37,7 @@ function normalizeMetadata(metadata) {
     canLoadCourseware: camelCaseObject(metadata.can_load_courseware),
     isStaff: metadata.is_staff,
     verifiedMode: camelCaseObject(metadata.verified_mode),
-    tabs: camelCaseObject(metadata.tabs),
+    tabs: overrideTabUrls(metadata.id, camelCaseObject(metadata.tabs)),
     showCalculator: metadata.show_calculator,
     notes: camelCaseObject(metadata.notes),
   };