Jade template, how to pass concrete object to pages? - node.js

I have a jade template for my node.js project. I would like to send an object to the jade template and pass it to a function inside the page (to render something).
I am sure I send the right stuff from the server like this
res.render(__dirname + '/pages/viz.jade', {
vizJson: newJson,
});
in the client I do something like this:
script
sunburst(#{vizJson})
Thus, inside a script function, I want to call a function that creates my visualization with some json I created on the server side.
The problem is that when rendered I have something like sunburst([Object object]). I also tried to send the stringified version of the JSON but when I do JSON.parse(#{vizJson}) it complains like Unexpected token &.
The json I send is always different and has different level of depths.
Does anyone knows what to do?
Thanks

I hope this is going to help someone. I solved it like this:
script
sunburst(!{JSON.stringify(vizJson)})
Notice the ! and the {...} wrapping the stringify method.

For this to work, you need to stringify on the server.
res.render(__dirname + '/pages/viz.jade', {
vizJson: JSON.stringify(newJson),
});
Then, as you mentioned, parse the JSON on the client.
script
sunburst(JSON.parse(#{vizJson}))
Hope that helps!

Oddly enough, for me the solution involved no calls to JSON.parse. I stringified my object on the server and just used the !{vizJson} method and got my object clientside.
Per the docs, unescaped string interpolation: http://jade-lang.com/reference/interpolation/

On the JS side, you send back
res.render(__dirname + '/pages/viz.jade', {
vizJson: JSON.stringify(newJson),
});
On the HTML side, I have found that something like:
JSON.parse( '!{vizJson}' )
works.

Related

get values from client side to server side (node.js + express.js)

I'm still trying to understand the concepts of node.js so please don't blame me if this is a dumb question..
In node.js, is it possible to get a value from index.jade to index.js?
For example:
index.jade
a(href="/bla" name="someName") Blabla
index.js
router.get('/bla', function(req, res){
//get value of name ("someName") or string ("Blabla")
console.log(req.body.name) ??
});
If this is not possible, I would like to know why...
Thanks.
No, it's not possible, for the simple reason that the name attribute in your HTML doesn't get passed to the server (any server, not necessarily a Node-based server).
If you want to pass a value in a GET request, you generally pass it as part of the URL:
a(href="/bla?name=someName") Blabla
This will generate the following HTML:
Blabla
In your server code, you can access the value using req.query.name.
Taking this a step further: if you have a variable available to your template called "name", you can use something similar, but a bit more dynamic:
a(href="/bla?name=" + encodeURIComponent(name)) Blabla
encodeURIComponent makes sure that any "special" characters (that may have a special meaning in URL's) will be encoded properly.

Render raw html in response with Express

I would like to know how to render a raw HTML string in a response with Express.
My question is different from the others because I am not trying to render a raw HTML template; rather I just want to render a single raw HTML string.
Here is what I have tried in my route file.
router.get('/myRoute', function (req, res, next) {
var someHTML = "bar"
res.send(someHTML);
});
But when I point my browser to this route, I see a hyperlink, instead of a raw HTML string. I have tried to set the content-type to text by doing: res.setHeader('Content-Type', 'text'); with no avail.
Any suggestions?
For others arriving here; this worked best for me:
res.set('Content-Type', 'text/html');
res.send(Buffer.from('<h2>Test String</h2>'));
Edit:
And if your issue is escaping certain characters, then try using template literals: Template literals
The best way to do this is, assuming you're using callback style, declare var output=""....then go through appending what you need to the output var with +=.... use a template literal (new line doesn't matter ${variables in here}) if it's a large string... then res.writeHead(200,{Content-Type: text/html); res.end(output)
Encode the HTML before sending it. Someone made a Gist for this: https://gist.github.com/mikedeboer/1aa7cd2bbcb8e0abc16a
Just add tags around it
someHTML = "<plaintext>" + someHTML + "</plaintext>";
Just a word of caution that the plaintext is considered obsolete which means browser vendors have no obligation to implement them. However ,it still works on major browsers.
Another way you could do it is
someHTML = someHTML.replace(/</g, '<').replace(/>/g, '>');

Meteor's Iron Router: get query parameter on both Client and Server Side

there
In my application, if someone pass a parameter on the URL I want to do different things on the template.
I know I can get on server side a query string using this.params.query but how can I pass it to client OR get this value on client-side?
In my case I will send an optional redirect on the URL, and if it was passed, after the main task, my app will redirect the user to the url given. But I just know how to see redirect on server side, not on client, so this information get lost when I, for example, submit a form
Could you help me?
You can access the router params in your template with:
Router.current().params.query
Maybe in your route you can do like this:
onBeforeAction: function() {
Session.set("query", this.params.query);
this.next();
},
Then somewhere on the client you can make a helper like this:
Template.yourTemplateName.helpers({
query: function() {
return Session.get("query");
}
});
I'm not sure what to do with your redirect, but maybe it will work in the helper. So your html would be something like:
{{#if query}}{{query}}{{/if}}
And in the helper you could possibly replace "return Session.get("query")" with something like "Router.go('/wherever-you-want-to-go');". Or just write another helper to run in your html if the query is positive.

node.js express.js Error handling in View

I am very new to node.js and express.js and in programming concepts. I already made a basic MVC modeled app on node and express.
My problem is how do you handle error, I got this following code:
exports.submitBloodRequest=function(kaiseki,resView,request){
var params = {
bloodCenterId:request.session.centerID,
bloodTypeId: request.body.bloodType,
requestQuantity:request.body.numberOfDonors
}
kaiseki.createObject('blood_center_request', params, function(err, res, body, success) {
if(success){
resView.redirect('/bloodRequest')
}else{
//WHAT TO DO HERE?
}
});
}
Kaiseki is just a middleware for parse.com, I don't know what to do if it got error. Usually I use ajaxForm.js to look for BadRequest then use javascript to display error message in my view.
I want my error to appear in the same page, where it is success, should I pass a json error to my view?
Or still use ajaxForm.js and instead of res.render or res.redirect I should use res.status(500)
Is there anyway to handle the error and showing it into the view. Without using any javascript to detect BadRequest?
And can a view have a optional variable? In my view If I didnt pass any value on it it gives me error like if i have #{variable} it asks for its value. Can it be made to be optional? Im using Jade Template
To respond to an XHR request with an error you can do something like return resView.status(500).send(err); which will send the err object back as JSON. If you want to render an HTML error page instead you can do return resView.status(500).locals({err: err}).render('/errorPage');
You didn't say which template engine you are using but most likely the #{} version will automatically escape HTML characters for you (turn < into <, etc) to avoid XSS attacks and rendering problems whereas !{} will render the contents of the variable directly without escaping, which is dangerous if the variable contains any user-generated content, but necessary if the variable has HTML you want rendered by the browser.

Get return value of `include` in jade template

What I basically try to accomplish is to re-use jade partials/templates when getting data through a socket connection. Non working example:
socket.on('company_created', function(company) {
var html = include _company;
$('#companies ul').append(html);
});
Normally I had to create a new li and set the content like so (which is working as expected):
$('#companies ul').append($('<li>').text(company.name));
This is okay for a simple list, but if I had complexer list and stuff, this could get messy pretty quick, plus I had to write plain HTML again, so I figured re-using my already existing jade templates with all their goodness would be awesome, but had not luck, yet.
Any clue?
PS: Please do not tell my to use Ember, Backbone, Derby, Meteor, Angular or whatsoever.
Thanks in advance!
You can compile your jade sources to JS with jade.compile. Then include these sources in the client-side javascript, include jade's runtime.min.js, and refer to your jade templates as to normal JS functions in your client-side code.
For example,
server.js
app.get('/templates/:template.js', function (req, res) {
var template = req.params.template;
response.end([
"window.templates = window.templates || {};",
"window.templates[\"" + template + "\"] = " + jade.compile(template + ".jade", { client: true; });
].join("\r\n"));
});
client.js
$(function() { $("#placeholder").html(window.templates["content"]({user: "Daniel" })); });
content.jade
h1: Hello #{user}!
index.jade
!!!
html
head
script(src='/lib/jquery/jquery.js')
script(src='/lib/jade/runtime.min.js')
script(src='/templates/content.js')
script(src='/scripts/client.js')
body
#placeholder
Note that the code above might be syntactically incorrect and is provided solely to illustrate the idea.
we have a build step that compiles them to functions sort of like penartur mentioned. I dont use extend or include (which dont work on the client anyway ATM), but personally I find we have absolutely no need for that on the client at all since the DOM provides all the separation we need.

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