meteor with flow router layout is rendered twice - layout

I don't know why but my layout is rendered two times.
Here is my index.html:
<head>
<title>title</title>
</head>
<body>
{{>layout}}
</body>
Here is my layout:
<template name="layout">
{{#if canShow}}
{{>Template.dynamic template=content}}
{{else}}
{{> loginButtons}}
{{/if}}
</template>
So here without route my template is display just one time.
Here is my route:
FlowRouter.route('/', {
action() {
BlazeLayout.render("layout", {
content: "home"
});
}
});
But with this route my template is display a second time.
This is my helpers, I think there is nothing to do with this problem but we never know.
Template.home.onCreated(function() {
this.autorun(() => {
this.subscribe('post');
});
});
Template.layout.helpers({
canShow() {
return !!Meteor.user();
}
});
Template.home.helpers({
cats() {
return Posts.find({});
}
});

you don't need to render layout in the body.
The router will take care of the rendering.
so, just have
<body>
</body>
or don't even have it at all.
Edit: Thanks to Keith, I have a better understanding of my problem. Here is his comment:
one thing to keep in mind, all the html you write in meteor isn't kept as html. It all gets converted to javascript. Things like index.html do not get pushed to the browsesr. Meteor just takes all the html you write converts it to javascript and renders what it needs to based on what your code says. This is how it knows todynamically change and rerender html
For things like changing title of the head or add meta etc, we can do it directely in the javascript.
ex: Meteor - Setting the document title

Related

POST FORM in node and receive data response back to same webpage

I have a webpage that takes form details, POSTS the data and should then show the results. I'm using express for my routing.
This all works fine by resending the data with the HTML template after the POST but I think there must be a better way by hiding the "results" HTML section then just showing it once the data is known from the form. I've shown a cutdown version of my pages below.
On first load, the page says "your result is undefined", which I would expect but is ugly.
I could remove the "result" section and create a 2nd HTML page to resend from the POST route with it in which would work but I think there must be a better way.
I want to hide the result section on 1st page load then make it appear on the button submit with the result data. I can get the section hide/unhide but I can't get the data results back to display them. On button submit the form results just appear in the weburl www.mywebsite.com/?data almost like a GET request
I have tried using FormData and npm 'form-data' in a POST but can't get it working following these examples https://javascript.info/formdata and https://www.npmjs.com/package/form-data.
My structure in Node is
Router.js file
return res.send(htmlFormTemplate({}));
});
router.post('/css',
[],
async (req, res) => {
let {data} = req.body;
///
result= do some calculation on {data}
///
return res.send(htmlFormTemplate({result}));
});
The htmlFormTemplate is a js file
module.exports = ({result}) => {
return `
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<form class="box" method ="POST">
<inputname="data" />
<button>Submit</button>
</form>
<script>
///tried form processing here
</script>
<section id="Results">
<ul><li>Your result is ${result}</li></ul>
</section>
</body>
</html>
`;
};
I'm self-taught and new so hope this makes sense and thanks for any help/ideas
You can check if the result variable is null before it gets to the section div:
${ result === null ? '' :
`<section id="Results">
<ul><li>Your result is ${result}</li></ul>
</section>`}
Like this, it wont show the result div if result if null.
There is a very simple to solve this problem,
just use some templating engine for ex EJS, its very easy to use and will help you better,
and your result is undefined because your using a promise and it might have happened that the response might have not come and you loaded the page. Just use await
return await res.send(htmlFormTemplate({result}));

Node.JS :How to forward to the login page with parameter?

I am building the login function with node.js, express,express-session, ejs.
This is the log-in page (i.e. index.ejs)
<html>
<head>
<meta charset="UTF-8">
<title>Video Chat Room</title>
<link rel="stylesheet" type="text/css" href="/css/style.css">
<style>
#message
{
color:red;
font-weight: bold;
}
</style>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script>
$( document ).ready(function() {
var messageBox=document.getElementById("message");
<%
if (typeof errorField!="undefined") {
switch (errorField) {
case "email":%>
messageBox.innerHTML="Your email address has been used by another user, please use another one.";
document.getElementById("email").focus();
<% break;
case "logoutSuccess":%>
messageBox.innerHTML="<%=alias%> has successfully logged out.";
<% break;
}
}
%>
});
</script>
</head>
<body>
<form method="post" action="/login">
Nick name/Alias:<input type=text required name="alias" value="<%=((typeof user=='undefined')?'':user.alias)%>"><br>
Email Address:<input type=email id="email" required name="email" value="<%=((typeof user=='undefined')?'':user.email)%>"><br>
<input type="submit" value="Login">
</form>
<div id="message">
</div>
</body>
</html>
Here is the server-side code(i.e. server.js)
........
app.get('/',function (req,res) {
res.render('../ejs/index.ejs');
});
app.post('/login', function(req, res) {
var alias = req.body.alias;
var email = req.body.email;
var user=require("./classes/user.js");
user.alias=alias;
user.email=email;
if (user.login) {
req.session.user = user;
res.redirect('/home/');
} else {
res.locals.errorField="email";
res.locals.user=user;
res.render('../ejs/index.ejs');
}
It works fine, however, when the login process failed, although the web output the login page(i.e. index.ejs), the browser address bar still stay in "/login"; is it possible to change the browser address bar to "/" and the index.ejs can read the errorField and user value also?
If you want a user login error to go back to /, then you need to do res.redirect("/"). If you want to add some parameters to that page that can be used either in server-side rendering or client-side rendering, then the simplest way to do that is to add query parameters:
res.redirect("/?error=email")
Then, either your server-side rendering or some client-side Javascript can pick up that query parameter and display something like a message in the page that explains what happened.
There are lots of ways to do something like this. Here's a partial list:
Send data in a query parameter that server-side rendering picks up and adds some explanatory text to the page.
Send data in a query parameter that client-side Javascript picks up and adds some explanatory text to the page.
Set a cookie that contains an error message that your server-side rendering will pick upon the redirect and then clear the cookie.
Set some error data in the user session object on the server that your server-side rendering will pick up when rendering the redirected page and the clean that info from the session.
Use an Express middleware module built for these temporary messages called flash.
Render an error page from the server (without an immediate redirect) and then have a client-driven redirect back to "/" that occurs after a few seconds time. The client-driven redirect can either be from a <meta> tag or can be client-side Javascript on a timer.

How to render the HTML into react component

I want to render the pure HTML coming from some external source into react component. I saw few solutions where people are talking about some conversion tools (HTML to JSX) but I want to handle everything in my component so while mounting it will get the HTML response and that needs to render.
You can use dangerouslySetInnerHTML for this:
function createMarkup() { return {__html: 'First ยท Second'}; };
<div dangerouslySetInnerHTML={createMarkup()} />
But as the method name suggests: you should be very sure of what you are doing there and the security implications it has.
This shouldn't be difficult to do . Assign your HTML to a div and then render it using {variable name} JSX allows you to do this and with ES6 integration you can also use class instead of className.
var Hello = React.createClass({
render: function() {
var htmlDiv = <div>How are you</div>
return <div>Hello {this.props.name}
{htmlDiv}
</div>;
}
});
ReactDOM.render(
<Hello name="World" />,
document.getElementById('container')
);
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.14.8/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.14.8/react-dom.min.js"></script>
<div id="container">
<!-- This element's contents will be replaced with your component. -->
</div>

How to change something dynamically in the main handlebars skeleton?

I am using handelbars as my templating engine and I am curious to whether I could edit the main handlebars file. What I can do at the moment is something like this:
main.handlebars:
<html>
<head>
</head>
<body>
<div id='headerBox></div>
<div id='contents'>{{{body}}}</div><!--all contents goes here-->
</body>
When I use this method I will could create templates e.g. home.handlebars etc.
But what If I wanted to change something dynamically in the main.handlebars? For example in my website, I would love to have a login form so I would like to have something like this in the main.handelbars:
<html>
<head>
</head>
<body>
<div id='headerBox>{{If logged in print name, if not print sign up}}</div>
<div id='contents'>{{{body}}}</div><!--all contents goes here-->
</body>
</html>
TLDR, how to I change something dynamically in the main handlebars skeleton.
Thanks!
You'll want to write a Handlebars Helper function. Since you didn't include anything about how you're verifying login, I'll write a little demo.
In your template file:
<div id='headerBox'>{{header}}</div>
Handlerbars.registerHelper('header', function() {
if (loggedIn) {
return //however you're getting a username
} else {
return Sign Up
}
});

node/express retrieving html templates from mongodb

Hi I'm new to node and I'm trying to make a simple blog.
I want to route /pages/:post to search a database for "post" and return an html template file that I can use as a partial.
var posts = {
'myarticle': {
template: partial1.html
}
};
var findPost = function (post, callback) {
if (!posts[post])
return callback(new Error(
'No post matching '
+ post
)
);
return callback(null, posts[post]);
};
app.get('/pages/:post', function(request, response) {
var post = request.params.post;
findPost(post, function(error, post) {
if (error) return;
return response.render('posttemplate', post);
});
});
and posttemplate is a template file like ejs (i'm not comfortable with Jade as of yet) that looks like
<html>
<% include ../partials/header %>
<body>
<% include /thereturnedpost %>
</body>
</html>
Is this possible? I've looked through documentation/tutorials but none of them are clear.
I'l answer with codes examples from my current project
<body>
<%- body %>
<script type="text/javascript" src="/vendors.js"></script>
<script type="text/javascript" src="/main.js"></script>
</body>
and
res.render('index', {
body: content
});
So your example is almost correct. After fetching the data from the database you send it to render function (in my case I render content ).
It is for the case when you keep in the db html string.
Also I can recommend you to use markdown (e.g. markdown-js) for the blog posts. It may be simpler to write and edit well formatted content, and less information to keep (comparing to html).
As per your coding, your blog post contents are static and are in template htmls.
If you get the data from db, you should modify your code such that the template file is with the HTML markup/ejs variables and send the data values separately.
This can be accomplished through ejs.renderFile method...https://www.npmjs.com/package/ejs2
Hope it will help you...

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