I've got a HighCharts javascript that i'm trying to convert to CoffeeScript, using some online converters.
However all of them error out with "missing operand"
Here's the code
$(function() {
$('#container').highcharts({
series: [{
name: "<%= x %>'",
data: [
<% #sprice = #price * #quantity %>
<% 0.upto(#years).each do |stack| %>
<%= number_with_precision(#sprice, precision: 2) %>,
<% #sprice = ((#sprice*percentage)/100)+#sprice %>,
<% end %>]
}]
});
});
Where's the missing operand tho? Does it have something to do with embedded ruby inside my JS script?
Script is working as intended inside HTML view file. But i'm trying to move it into controller's js file to clean it up abit. Controller's js file is in coffescript by default, so that's where im kind of stuck.
Any help appreciated, thanks!
As noted above:
If #years is small
then ERB a couple simple scalars and then build the array in CoffeeScript;
If #years is large
then do the heavy lifting in your controller and stuff the data into your CoffeeScript as a one line JSON blob.
Or AJAX it or split the data out into a separate piece of JavaScript and leave the code as CoffeeScript.
References
CoffeeScript, TypeScript? How about JavaScript
Related
Action: a javascript action attempting to retrieve data based on two parameters, a user-input one and an issuing page parameter.
whereas in the past something like the following would work:
<%= javascript_tag do %> chart.data = data_<%=j params[:nation_id] %>; <% end %>
now with the javascript being 'packed', the compilation of syntax like <%=j params[:nation_id] %> does not work and returns :
/search.json?nation_id=%22%3C%=j%20params[:nation_id]%20%%3E%22&q=mi
modifying the packs/muni.js file as follows, also does not generate a proper url for the search function
var options = {
url: function(phrase) {
return '/search.json?nation_id="#{params[:nation_id]}"&q=' + phrase;
},
getValue: "name",
};
returning
/search.json?nation_id=%22
the page is set with /new?top%5Bnation_id%5D=1&commit=Set
How does the javascript pack need to be written?
Javascript pack is not rendered for each request/visitor - whole point is that it is packed once per deploy and is the same for all (except for when you have several packs, dynamic module loading and other advanced techniques, but still code is not changed per request). In fact, older method with asset pipeline is very similar in this aspect.
Do not try using ruby inside the pack, but instead think of a way to pass the parameter to the js code.
For example, you can pass it via a adding some html tag an querying it from javascript:
In view:
<meta name="nation_id" content="<%= params[:nation_id] %>" />
in js:
nation_id = document.querySelector('meta[name="nation_id"]').content;
return `/search.json?nation_id=${nation_id}&q=${phrase}`;
PS. also you might need to escape your phrase with encodeURIComponent
I am using the FileStack API and the file picker gem (https://github.com/Ink/filepicker-rails). I have an Attachment model that has a :title as a string. When a file is uploaded, the URL from the FilePicker API is stored as the :title. But the gem has a onchange method that returns an event variable as a JSON object that contains attributes of the file. I use JavaScript to access those attributes but I want to find a way in Rails to store those attributes, accessed via JavaScript, in a Model so that I can access it through the rest of the Rails app.
<%= filepicker_js_include_tag %>
<%= simple_form_for(#attachment) do |f| %>
<%= f.filepicker_field :title, onchange: 'onUpload(event)' %>
<%= f.submit %>
<% end %>
<script>
function onUpload(event) {
console.log(event);
var name = event.fpfile.filename;
console.log(name);
}
</script>
Update:
So after looking into your solution and googling around I am using ajax to send the data via routes to the controller. Below is my updated Javascript as well as the route and controller. When I render and inspect the #foo instance variable it is nil. So my data isn't getting passed properly. Furthermore, this whole process from the firing of the Javascript function to displaying the index view is now very very slow. I think I have the right idea after viewing your solution and doing more digging but I'm missing something and/or overcomplicating this. Any advice would be much appreciated.
<script>
function onUpload(event) {
var name = event.fpfile.filename;
jQuery.ajax({
data : { data_value: event },
type: 'post',
url: "/attachment/index"
});
}
</script>
Route
post 'attachments/' => 'attachment#index'
Controller
def index
#attachments = Attachment.all
#foo = params[:data_value]
end
View (returns nil)
<%= raise #foo.inspect %>
If you're using Postgres 9.3 or above you should consider using the hstore module and creating a JSON column. In a migration you can do:
add_column :your_model, :your_attribute, :json
And then you can just update YourModel.your_attribute => {'your': 'JSON here'}
Docs here: http://edgeguides.rubyonrails.org/active_record_postgresql.html#json
If you're using MySQL it's tricky, but doable. You have to create a text column and save the JSON as a string, and parse it every time you interact with it. Postgres is definitely better at handling JSON. I realize that this answer relies on an assumption, so if you're not using one of the two data stores mentioned, let me know and I'll pull it down.
I'm writing an app that uses Rails on the backend and javascript/backbone on the frontend. I'm trying to bootstrap some rails models into my javascript. Specifically, I'd like to load the contents of #courses into a js variable called window.courses. I've got the following in an html.erb file.
<%= javascript_tag do %>
window.courses = JSON.parse('<%= #courses.to_json %>');
<% end %>
I'm expecting the erb preprocessor to render this into valid javascript, like so
<script type="text/javascript">
//<![CDATA[
window.courses = JSON.parse('[{"code":"myCourseCode", ...
//]]>
</script>
... but, instead, I'm getting code that includes HTML entities.
<script type="text/javascript">
//<![CDATA[
window.courses = JSON.parse('[{"code":"myCourseCode", ...
//]]>
</script>
Obviously, I get javascript errors when I try to parse this.
Does anyone know how I can deal with these HTML entities in order to produce valid javascript? I realize that one option would be to unescape the entities on the client side, but this seems like a roundabout solution. Is there a way that I can get Rails to produce JSON that doesn't need unescaping?
If you intend to use raw(obj.to_json) you MUST ensure the following is set.
ActiveSupport.escape_html_entities_in_json = true
The question is solved by my comment, just for the record:
Rails escapes strings that are printed using <%= 'string' %>. By this, it is save to ouput user data.
So, if you don't want Rails to escape the output, you have to tell Rails explicitly by using raw('string').
In your code, that would be:
<%= raw(#courses.to_json) %>
My setup: Rails 3.0.9, Ruby 1.9.2, jQuery 1.6.2
Rails
constants.rb (initializer file)
DEFAULT_REPLY = "Add a reply..."
Rails
index.html.erb
<%= javascript_include_tag 'reply' %>
...(rest of view code)...
reply.js
$(function() {
var default_reply = <%= h DEFAULT_REPLY -%>;
...(rest of jQuery code)...
});
This throws an error Uncaught SyntaxError:Unexpected token %=, I tried to enclose it in quotes like var default_reply = '<%= h DEFAULT_REPLY -%>' and it output the value as is, meaning default_value has the value of <%= h DEFAULT_REPLY -%>' which is clearly not what I intended. What am I doing wrong?
EDIT
Given the feedback, I have reconsidered and is now using a local variable and jQuery to pull the value from the textarea upon page load.
You need to add .erb to the end of your .js file, along with add the quotes around the string.
The name of your javascript file should be reply.js.erb.
Currently, your .js file is not being run through rails, and is being served statically. That is why when you put the quotes around the string, it output the string '<%= h DEFAULT_REPLY %>' instead of the correct text.
I'd strongly recommend against this approach but I think you're confusing two things here.
Assuming reply.js is in public/javascripts/reply.js, this is a static JS file that is served up by your server. You cannot put any dynamic ("server side") code in here as the file is not evaluated in any manner, just passed back statically.
If you want a global JS variable to use in your files, you'd need to do assign it in your layout file app/views/layouts/application.html.erb or in your action files (index.html.erb, show.html.erb, etc).
Any ERB file is evaluated before returning it, so you could put
<script type='text/javascript'>
$(function() {
var default_reply = "<%= escape_javascript DEFAULT_REPLY %>";
});
</script>
above the <%= yield %> statement of your layout file.
Again, I'd STRONGLY recommend against this approach but if that's why you need, I think this will solve it.
It sounds like you named your view template incorrectly, does it end in .html.erb? If not, it won't evaluate the ERB fragment you pasted.
Once you fix that, you can embed what you want with the following ERB code:
$(function() {
var default_reply = "<%= h DEFAULT_REPLY -%>";
...
});
If it is a rails 3 App why are you using that syntax? try:
var default_reply = <%= DEFAULT_REPLY %>;
I have a js.erb template with the following code:
var latlng = new google.maps.LatLng(<%= session[:lat] %>, <%= session[:lng] %>);
I'm now trying to do the opposite (insert javascript into ruby):
<% session[:lat] = javascript_tag("document.write(location.lat());") %>
I think you're missing the point of Javascript.
Ruby code (<% .. %> parts in your examples) is run on the server.
Javascript code (var latlng = new google.maps.LatLng(10, 20); and document.write(location.lat());) is executed in the browser.
It's also executed after ruby code, when server has processed request and generated result page already.
If you want to know value of location.lat() on the server, you'll have to send it from the browser to the server in AJAX request. Any popular Javascript library will help with that.
Maybe you could try <%= raw [ruby/rails code] %>
This link may help: http://groups.google.com/group/rubyonrails-talk/browse_thread/thread/a160d9c2e55cfe36