Add a landing page for app purchases

This page doesn't display anything yet, it just asks the backend for a
token and then redirects to another page to give flathub-authenticator
the token. Finally, flathub-authenticator redirects once again to
another landing page to let the user know the transaction is finished.

pages/purchase/finished.tsx

@@ -0,0 +1,27 @@
+import { GetStaticProps } from 'next'
+import { useTranslation } from 'next-i18next'
+import { serverSideTranslations } from 'next-i18next/serverSideTranslations'
+import { NextSeo } from 'next-seo'
+import Main from '../../src/components/layout/Main'
+
+export default function Purchase({ providers }) {
+  const { t } = useTranslation()
+
+  return (
+    <Main>
+      <NextSeo title={t('thank-you-for-your-purchase')} noindex={true} />
+      <div className='main-container'>
+        <h1>{t('thank-you-for-your-purchase')}</h1>
+        {t('safe-to-close-page')}
+      </div>
+    </Main>
+  )
+}
+
+export const getStaticProps: GetStaticProps = async ({ locale }) => {
+  return {
+    props: {
+      ...(await serverSideTranslations(locale, ['common'])),
+    },
+  }
+}

pages/purchase/index.tsx

@@ -0,0 +1,74 @@
+import { GetStaticProps } from 'next'
+import { useTranslation } from 'next-i18next'
+import { serverSideTranslations } from 'next-i18next/serverSideTranslations'
+import { NextSeo } from 'next-seo'
+import { useRouter } from 'next/router'
+import { ReactElement, useEffect, useState } from 'react'
+import { toast } from 'react-toastify'
+import Main from '../../src/components/layout/Main'
+import Spinner from '../../src/components/Spinner'
+import { generateTokens } from '../../src/context/actions'
+import { fetchLoginProviders } from '../../src/fetchers'
+import { LoginProvider } from '../../src/types/Login'
+
+const PERMITTED_REDIRECTS = [/http:\/\/localhost:\d+/, /http:\/\/127.0.0.1:\d+/];
+
+export default function Purchase({ providers }) {
+  const { t } = useTranslation();
+  const [waiting, setWaiting] = useState(false);
+  const [error, setError] = useState('');
+  const [token, setToken] = useState('');
+
+  const router = useRouter();
+
+  useEffect(() => {
+    if (!router.isReady) return;
+
+    let redirect = router.query.return.toString();
+    if (!PERMITTED_REDIRECTS.some(r => redirect.match(r))) {
+      setError(t('incorrect-redirect'));
+      return;
+    }
+
+    let refs = router.query.refs.toString().split(";");
+    /* We get refs in the form app/<app ID>/<arch>/<branch>, we just want the app ID part */
+    let appIDs = refs.map(ref => ref.split("/")[1]);
+
+    setWaiting(true);
+    generateTokens(setToken, appIDs)
+      .catch(err => toast.error(t(err)))
+      .finally(() => setWaiting(false));
+  }, [router]);
+
+  useEffect(() => {
+    if (token) {
+      window.location.href = router.query.return.toString() + "?token=" + token;
+    }
+  }, [token]);
+
+  let content: ReactElement = null;
+
+  if (waiting)
+    content = <Spinner size={150} />;
+
+  return (
+    <Main>
+      <NextSeo title={t('purchase-apps-title')} noindex={true} />
+      <div className='main-container'>
+        {content}
+      </div>
+    </Main>
+  )
+}
+
+// Need available login providers to show options on page
+export const getStaticProps: GetStaticProps = async ({ locale }) => {
+  const providers: LoginProvider[] = await fetchLoginProviders()
+
+  return {
+    props: {
+      ...(await serverSideTranslations(locale, ['common'])),
+      providers,
+    }
+  }
+}

public/locales/en/common.json

@@ -121,6 +121,10 @@
     "install": "Install",
     "screenshot": "Screenshot",
     "donate": "Donate",
+    "purchase-apps-title": "Purchase Apps",
+    "thank-you-for-your-purchase": "Thank you for your purchase!",
+    "safe-to-close-page": "It is safe to close this page.",
+    "incorrect-redirect": "Incorrect redirect specified.",
     "other-apps-by-developer": "Other apps by {{developer}}",
     "loading": "Loading…",
     "could-not-find-match-for-search": "Could not find a match for search.",

src/context/actions.ts

@@ -1,7 +1,7 @@
 import { ParsedUrlQuery } from "querystring";
 import { Dispatch } from "react";
 import {
-  LOGIN_PROVIDERS_URL, LOGOUT_URL, USER_DELETION_URL, USER_INFO_URL
+  LOGIN_PROVIDERS_URL, LOGOUT_URL, TOKEN_GENERATION_URL, USER_DELETION_URL, USER_INFO_URL
 } from "../env";
 import { UserStateAction } from "../types/Login";
 
@@ -152,3 +152,39 @@ export async function deleteAccount(
     throw 'network-error-try-again'
   }
 }
+
+
+/**
+ * Generates a token to download a set of apps.
+ * @param token Function to set the token when finished
+ * @param waiting Function to set the async state of the component
+ * @param error Function for displaying errors (usually component state)
+ * @param appids A list of app IDs to generate tokens for
+ */
+ export async function generateTokens(
+  token: Dispatch<string>,
+  appids: string[],
+) {
+  let res: Response
+  try {
+    res = await fetch(TOKEN_GENERATION_URL, {
+      method: 'POST',
+      credentials: 'include',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify(appids)
+    })
+  } catch {
+    throw 'network-error-try-again';
+  }
+
+  if (res.ok) {
+    const data = await res.json()
+    if (data.token) {
+      token(data.token);
+    } else {
+      throw data.message;
+    }
+  } else {
+    throw 'network-error-try-again';
+  }
+}

src/env.ts

@@ -38,6 +38,7 @@ export const LOGIN_PROVIDERS_URL: string = `${BASE_URI}/auth/login`
 export const USER_INFO_URL: string = `${BASE_URI}/auth/userinfo`
 export const LOGOUT_URL: string = `${BASE_URI}/auth/logout`
 export const USER_DELETION_URL: string = `${BASE_URI}/auth/deleteuser`
+export const TOKEN_GENERATION_URL: string = `${BASE_URI}/generate-download-token`
 
 export const IS_PRODUCTION: boolean =
   process.env.NEXT_PUBLIC_IS_PRODUCTION === 'true'

src/types/Purchase.ts

@@ -0,0 +1,8 @@
+export interface Transaction {
+  token?: string;
+  appids: string[];
+}
+
+export interface TransactionStateAction {
+  token: string;
+}