如何创建PWA MANIFENT.json动态？ [英] How to create PWA manifest.json dynamic?

问题描述

我在清单.json中使用静态变量变量创建了一个功能，例如：

 -- name
 -- short_name
 -- start_url

它在"添加到主屏幕"上运行得很好。 当我动态设置MANIFEST.json变量时，添加到屏幕不起作用

基本上我有一个电子商务PWA。我的要求如下：如果用户访问应用程序URL(例如：www.Example.com/Products/PRODUCT_NAME_A)，他应该能够在主屏幕上创建一个快捷方式链接，或者根据不同的URL创建许多他们想要的快捷方式链接。

您还可以查看我到目前为止用Java脚本编写的代码：

var domain = document.location.origin;
var currentUrl = window. location. href;

var myDynamicManifest = {
    "name": "My App",
    "short_name": "My App",
    "description": "This is my App",
    "start_url": currentUrl,
    "scope": ".",
    "background_color": "#5F6EDD",
    "theme_color": "#efbc4b",
    "orientation": "portrait",
    "display": "standalone",
    "lang": "en",
    "dir": "ltr",
    "icons": [
        {
          "src"     : domain + "/images/logo/logo_70x70.png",
          "sizes"   : "70x70",
          "type"    : "image/png"
        },
        {
          "src"     : domain + "/images/logo/logo_120x120.png",
          "sizes"   : "120x120",
          "type"    : "image/png"
        },
        {
          "src"     : domain + "/images/logo/logo_144x144.png",
          "sizes"   : "144x144",
          "type"    : "image/png"
        },

    ]
    }

const stringManifest = JSON.stringify(myDynamicManifest);

const blob = new Blob([stringManifest], {type: 'application/javascript'});

const manifestURL = URL.createObjectURL(blob);

document.querySelector('#manifest').setAttribute('href', manifestURL);

我预计输出如下：http://prntscr.com/oej48u

推荐答案

我意识到这是一个老问题。但是，我想我应该传达一下我是如何解决这个问题的。我的前端是通过Netlify服务的，后端API都是GCP云函数。我添加了一个Cloud函数，它响应/manifest?startUrl=...&name=...并返回正确的清单.json内容。然后，在单页应用程序中，当页面加载或用户导航时，它会动态更新标题<link />以指向适当的URL。

客户端：

const manifest = document.getElementById('manifest');
const nextManifest = document.createElement('link');
nextManifest.id = 'manifest';
nextManifest.rel = 'manifest';
nextManifest.href =
  `https://<cloud function host>/manifest?startUrl=${
    encodeURIComponent(`/events/${token}`)
  }&name=${encodeURIComponent(event.name)}`;
manifest.parentNode.replaceChild(nextManifest, manifest);

服务器端：

const manifest = {
  "short_name": "Photo Feed",
  "name": "Photo Feed",
  "icons": [
    {
      "src": "shortcut-icon.png",
      "sizes": "16x16",
      "type": "image/png"
    },
    {
      "src": "mobile-app-icon.png",
      "sizes": "180x180",
      "type": "image/png"
    }
  ],
  "start_url": ".",
  "display": "standalone",
  "theme_color": "#591A0C",
  "background_color": "#06B8B3"
};

/**
 * Responds to any HTTP request.
 *
 * @param {!express:Request} req HTTP request context.
 * @param {!express:Response} res HTTP response context.
 */
exports.manifest = (req, res) => {
  res.set('Access-Control-Allow-Origin', '*');

  if (req.method === 'OPTIONS') {
    res.set('Access-Control-Allow-Methods', 'GET');
    res.set('Access-Control-Allow-Headers', 'Content-Type');
    res.set('Access-Control-Max-Age', '3600');
    res.status(204).send('');
    return;
  }

  if (req.method === 'GET') {
    // take /?startUrl=<url> and return a manifest file
    // with `star_url`, same with name
    if (req.query.startUrl) {
      res.json({
        ...manifest,
        short_name: req.query.name || manifest.short_name,
        name: req.query.name ? `${req.query.name} Photo Feed` : manifest.name,
        start_url: req.query.startUrl,
      });
    } else {
      res.json(manifest);
    }
  }

  res.status(405).send();
};

这篇关于如何创建PWA MANIFENT.json动态？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！