I'm writing an aurelia application with aurelia-fetch-client library.
When I try to post an object to my api service I get the error:
TypeMismatchError
In console only from Edge. Other browsers (Chrome, Firefox and IE11) have no problems. There are no description or any other details about it.
In all but the newest versions of Edge you need to include the fetch polyfill in order for aurelia-fetch-client to work. I think it's supported since version 14 but I wouldn't necessarily rely on it. Edge is known to be quirky with some of these things (the Promise implementation is also horribly slow, which is why I personally always use bluebird)
You can install it with npm i whatwg-fetch --save and make sure to import it + include it in your bundle config (the instructions for this depend on which build system you're using)
Related
I am using Vue CLI to create a Vue 2.0 project and one of the options is using Babel. I understand Babel is a transpiler but what exactly does it do? I created a project with it and another without it and I don't see the difference so what exactly is the pro/con of it ? I can't see offhand what it is doing.
You are correct. Babel is a transpiler. It transpiles your JavaScript code to one or more taget browsers, that does not support the lastest fetures. You will not see any difference, if using a newer browser.
Babal usually only makes sense if you need to support older browsers, like IE 11 or browsers from before 2017.
I've recently installed some npm package (recommended Kubernetes client) for my react app.
After writing code that uses the package and deploying the code for testing I got some weird errors about missing functions or packages. Then I've read the documentation and realized that the package was Node-only.
Is there any way to check that the npm package works in browser before writing code that uses the package?
Python packages specify compatible python versions. Do npm packages have something like this whether they indicate support for particular Node versions and the browsers?
Some packages/libraries contain .browserlistrc file which I've found to be a starting point to find out the browsers and platforms the devs intend to support or have their code compile for. While it may not always be true and the package might just be able to support a browser that isn't mentioned, it's a good starting point. It surely helps to find out if IE (the bane of front-end dev) is supported or not.
Then again many packages don't necessarily include a .browserlistrc. You can then check the package.json for a "browserslist" field.
If neither are found, you can always clone the repo and add your own .browserlistrc in the root with queries that will let you know if the package supports your intended browser or platform - little more work but yeah it can help. Not full proof but a decent enough way to find out.
Though the best answer is really to just ask the maintainers.
I am trying to deploy a vue application. I have to use Firefox ESR as browser (45.4.0) but I get the following error: TypeError: Object.values is not a function. If I use a different browser it works fine.
Could anyone help me?
Thank you
Support for Object.values was introduced in Firefox 47.
Your browser is from 2015. That is hideously ancient in Internet terms. Upgrade it.
(If you really want to to get the Vue application to work, you'll need to set up a Polyfill for Object.values. There is one linked from the MDN page I linked to above. It should also be available in core-js which can be used with Babel in the transpiling step of your build process.)
Say I wanted to support IE11 (and sadly, I do), how would I go about making gatsby develop work on that poor old browser?
Right now, I get this message:
webpack-hot-middleware's client requires EventSource to work.
This polyfill looks promising, but that's as far as I've made it.
Any help?
P.S. Probably worth mentioning that I'm using Gatsby v 2.4.7
Looks like Gatsby doesn't support IE in development, only in production, so no polyfills will be added and IE will error when using gatsby develop.
https://www.gatsbyjs.org/packages/babel-preset-gatsby/
Can confirm on my project that running gatsby develop doesn't make it work for IE11, but using gatsby build does. When running gatsby develop, all I could see on IE11 is a blank page.
As per the documentation of Gatsby, You need to use babel 7.
Babel helps ensure the JavaScript you write works across different browsers (including older versions of Internet Explorer).
Reference:
Babel 7 (Gatsby)
Gatsby leverages Babel 7’s ability to automatically add polyfills for your target browsers.
Newer browsers support more JavaScript APIs than older browsers. For older versions, Gatsby (via Babel) automatically adds the minimum “polyfills” necessary for your code to work in those browsers.
If you start using a newer JavaScript API like [].includes that isn’t supported by some of your targeted browsers, you won’t have to worry about it breaking the older browsers as Babel will automatically add the needed polyfill core-js/modules/es7.array.includes.
Reference:
Browser Support
Does it still make sense to use Express.js with io.js or does io.js have some sort of built-in functionality now that Express.js gave or do we still rely on Express.js. I mean Express.js doesn't extend io.js, it extends node.js.
I'm trying to figure out how you'd do the Web Server part if using io.js.
Think of io.js just as a new release of node.js. They have essentially identical feature sets and are essentially drop-in compatible with each other. You use any library from npm in the same matter on either io.js or node.js. Express.js and most other libraries in npm work on both just fine. There are still many npm modules that contain binary add-ons that don't yet work with io.js, but that should sort itself out quickly enough.