how do I refresh a rails path with an error message using ajax. I'm waiting for a callback from a payment API and if I get an error I want to reload the page and show the error. Problem is I'm using ajax. How can I pull this off ?
Refreshing the page to display a simple feedback error is completely unnecessary and long-winded. A much cleaner, and more direct method, is to use js to update the dom within the callback.
A very very simple demonstration:
$(".errors").append('<li>My error</li>');
In the name of simplicity, do that (or something similar within javascript), don't redirect just to display an error.
If error is persisted on database, you can use window.location on callback function in order to relaod the page with errors.
In the action that responds to the AJAX request you can do
flash[:alert] = "My error"
And then have the action render the redirect as such:
render js: "window.location.href = '#{my_named_route_path}'"
Or, you may want to write a method to abstract this, such as:
app/controllers/application_controller.rb
def redirect_to_via_xhr_if_applicable(url, options = {})
flash[:info] = options[:info] if options.key?(:info)
flash[:alert] = options[:alert] if options.key?(:alert)
flash[:notice] = options[:notice] if options.key?(:notice)
if request.xhr?
render js: "window.location.href = '#{url}'"
else
redirect_to(url)
end
end
Then you can just make this call from your AJAX (or non-AJAX) action:
redirect_to_via_xhr_if_applicable(my_named_route_path, alert: 'My error!')
Related
I've been reading a lot about Rails and AJAX and 5.1 Unobtrusive javascript. It explains a lot about responding to Rails version of AJAX calls with a .js file for example.
However what im wanting to do isn't serving up an entire .js file, it's simply updating an element after a <% link_to %> POST request. From my understanding setting remote: true submits it as a AJAX request.
Essentially I have a "Post" which a user can like via a linked Like button. This sends a POST request to the "Post" controller which updates a post to liked and adds a like to the post.
Unfortunately to see the effects of the post being liked (Which is simply that the link changes color as well as the font-awesome icon) you need to refresh the page. I basically want it to update without needing refresh.
I "think" based off what i've read I need to make a respond do and respond via .js to the request with a .js file in the view I want to update (for instance if the controller action is called "like", maybe a like.js.erb file in the view im updating?). But I don't want to serve an entire new page..or would this simply just run the .js?
Then I could do something like $('i.fa-icon#id').style.color = "blue" or something? (Im assuming I can send data from the controller to the .js.erb file?). Not sure the best way to do this, don't rails elements a lot of times have some sort of data-attribute or something (Im still a beginner at this).
Your description is quite correct!
Opposed to the other answer, you don't even need a event listener but as you said you want to have a respond_to in the controller.
So starting from the html:
# post/index.html.erb
<div id="like-button">
<%= button_to "Like this post", post_path(#post), remote: true %>
</div>
Note, that when you use a button_to helper it'll be a POST request by default.
If you click it, it'll go to the controller#update, which you want to change to this:
#posts_controller.rb
...
def update
#post.save
respond_to do |format|
format.html { redirect_to post_path(#post) }
format.js # <-- will render `app/views/posts/update.js.erb`
end
end
Note: the format.html is rendered when JS is disabled.
Now in the scenario that JS is enabled, it executes the app/views/posts/update.js.erb file. It can look like this:
const likeButton = document.getElementById('like-button');
likeButton.innerHTML = '<%= j render "posts/liked-link", post: #post %>';
What is the last line doing? Of course, you can change the style directly with the JavaScript, but you can also render a new partial - and this you will create in a new html file:
# app/views/posts/liked_link.html.erb
<div id="like-button ">
<p>"You liked this post!" </p>
</div>
I just changed the link/button to ap now, but of course you can do whatever you want.
Hope that makes sense :)
Not sure if I understand the question, but if you want to update like button:
What you want to do is to add an event listener to the button, and when clicked it makes a POST request to whatever route handles the likes(with the correct parameters) and your controller should respond with the like object (or whatever in the database gets stored). Have your post request on success method to grab the like button and change it to whatever you want it to look like
$(“#like-btn”).click(function(){
Rails.ajax({
url: "/some/url/to/like/controller",
type: "post",
data: [your post data],
success: function(data) { $(`#${ data[“btn-name”] }`).attr(“color”, “blue”; }
})
}
You can stick this script right in the bottom of the html page
You don’t have to do it exactly like this, just giving you an idea of how to set up the pattern of having JavaScript and Ajax handle the post request and updating of the frontend instead of using html buttons
I posted a very poor question about this earlier, so I am reposting and making it MVCE.
I'm building a messaging service with Rails and AJAX. So far I can submit a message through a form, it will update in the HTML DOM, an AJAX POST method will send it to the controller, and the controller will save it in the database.
Now I need to add an AJAX method that will GET the message that was just submitted -- so that other users (in other browsers) will be able to view it.
Currently, and this is a hack job way of doing it, in my JS code I set a timeout that calls an AJAX GET function every half second. Is there a better way to do this -- as in, once the controller saves the message can it call the AJAX function? The AJAX code looks like this:
function retrieveMessages(){
var message;
<%debugger%>
$.ajax({
type:"GET",
url:"<%= messages_get_path %>",
dataType:"json",
data: { what_goes_here: "blah" }, //this is the part I do not understand -- see below
success:function(data){
message = data;
console.log(data)
}
});
setTimeout(retrieveMessages, 500);
}
$(document).ready(function(){
//get messages
setTimeout(retrieveMessages, 500);
... more irrelevant
The line data: { what_goes_here: "blah" } doesn't make sense to me. What is the syntax for the controller to send data back to be stored into data:? Furthermore, from the console I can see that what_goes_here is being passed as a parameter to the controller -- again this doesn't make sense to me.
My route looks like this get 'messages/get', :to => 'messages#get' (this might be incorrect?)
rake routes shows
messages_get GET /messages/get(.:format) messages#get
And as of now, I don't have anything in my controller other than a respond_to because at this point I'm just trying to call the controller. What is the syntax to send data back to the AJAX method?
def get
debugger
respond_to do |format|
format.html
format.json {render json: #variable} //is this #variable being passed to the AJAX call?
end
end
UPDATE
This makes more sense to me... the AJAX method simply calls the def get function. The def get function then finds the message in the database, and stores it in an instance variable. Subsequently, I can add some Javascript code that will insert it into the DOM. However I must have something wrong in my routing because I'm getting (in the console) http://localhost:3000/messages/get 404 (Not Found)
What you are doing, as you suspect, is not effective. The more users are online the more will be load from these refreshing requests, most of them probably returning no new data.
You should consider more active way of notifying your browsers about changes on the server. One option is to use ActionCable.
I have a custom extension and i am working on functionality enhancement.
i have a custom grid and when i click on edit some part of the form comes from.
Hello/Mymodule/Block/Adminhtml/Mymodule/Edit/Field/Items.php
from the items.php i am sending ajax request to adminhtml controller function and implementing something there. now i want to render that items.php block onsuccess of ajax post.
I used this in controller after implementing things in database.
$table= $this->getLayout()->createBlock('mymodule/adminhtml_mymodule_edit_field_item');
$response['itemstable'] = $table;
return $this->getResponse()->setBody(Mage::helper('core')->jsonEncode($response));
When i tried to get that in onsuccess of ajax
var json = response.responseText.evalJSON(true);
alert(json.itemstable);
it shows nothing
Please help
I think you need to change the second line to
$response['itemstable'] = $table->_toHtml();
otherwise you won't get the html output of the created block.
Rails 3, JRuby
I recently took part in a quick crash course in jQuery that included a bit of ajax partial rendering. This got me thinking, could I use this to poll the Rails server using setInterval(), every x seconds to refresh a specific part of my page constantly?
The problem I'm having is how I could use the $.get() method to grab the url of the partial and reload it using load(). This is where the confusion starts- using Rails 3, I have a partial called "_microposts", rendered within a div with an 'id="gf" ' (gf meaning global feed). This happens on my Rails app homepage, so the url in this case would be "//localhost:8080/home" and not the url of the partial.
Here is my initial javascript/ jQuery
<script>
$(document).ready(function() {
setInterval(function (e) {
var url = $.get("<%= escape_javascript render :partial =>
'microposts/micropost', :locals => {:microposts => #microposts }%>");
$('#gf').html('loading...').load(url);
},10000);
});
</script>
This looks wrong, and so far, just blanks out my _microposts partial after 10 seconds (so the setInterval is working, and it's definitely updating the correct area, just with a blank space!)
Edit:
Thinking about my problem, I realised that this is similar to updating a partial from an event, such as clicking a button or something. The only real difference is the "event" that should trigger this the setInterval() function. So, my revised jQuery code is as follows:
<script>
$(document).ready(function() {
setInterval(function (e) {
$('#gf').html("<%= escape_javascript render :partial =>
'microposts/micropost', :locals => {:microposts => #microposts } %>")},
10000);
});
</script>
Unfortunately now, nothing seems to be happening from a user point of view, but the server is showing an ajax request every 10 seconds.
So why can't I poll for updates using ajax, and apply the changes to my _microposts partial? Is $.get the correct function to use in this case? What would the url for the load() method be when trying to re-load a partial?
Thanks,
Hopefully this will help anybody who wants to refresh a partial using ajax- especially if you're a beginner following Michael Hartl's tutorials to learn Ruby on Rails. Here's how I managed to solve my problem.
Firstly, I created a separate .js.erb file in the micropost view folder called 'polling.js.erb' that will refresh the global feed partial.
$('#gf').html("<%= escape_javascript render :partial =>
'microposts/micropost', :locals => {:microposts => #mps} %>");
I needed to write a method in the micropost controller that will correspond with the above javascript- this essentially supplies the information needed to refresh the partial. It's basically a simplified version of my index method in the micropost controller and avoids executing the additional code that's not needed for the partial I want to refresh.
def polling
#mps = Micropost.all #add some paginate code if you wish
#micropost = current_user.microposts.build(params[:micropost])
end
I then revised my javascript code, as I wanted to call the polling method every 5 seconds, loading the information specific to the current_user of my webapp.
$(document).ready(function() {
setInterval(function () {
$.ajax('microposts/<%= current_user.id %>/polling');
} , 5000);
});
Finally, I updated my routes.rb file to allow a web browser to call my polling method, using a get request, without causing a routing error. I'm using a member do block because the request is passing the current_user id via the request.
resources :microposts do
member do
post :polling
end
end
I'm not even sure how to ask this question in a way thats understandable.
Basically, I'd like to do some javascript using a js.erb after I save. I'm submitting the form using a regular javascript/coffee-script file (if all fields are filled in correctly, then the form is submitted, else the form does nothing & just displays errors).
Part of my coffee-script:
fieldCorrectResponse: (fields, response) ->
if fields == correct
$('#new_mail')[0].submit()
else
$('#mail_error').text('error while filling out form')
my mail controller:
def create
#mail = Mail.new(mail_params)
if #mail.save
#PERFORM SOME JS USING A JS.ERB
else
render :new
end
END
So I guess what I'm really is asking is, how would you call a js.erb in the controller?
Wrote the solution to my problem below..
You should be able to render js and use create.js.erb.
Please try:
# MailsController
def create
#mail = Mail.new(mail_params)
if #mail.save
respond_to do |format|
format.js
end
else
render :new
end
END
Then, implement your javascript in app/views/mails/create.js.erb.
"do some javascript" isn't terribly descriptive. are you wanting to return a JSON object from the create action, which can then be parsed by the success callback on your jquery? Or do you want to have a template that has javascript in it that gets called as a result of the save action?
vinod covered the second way. make sure you have your routes set up correctly.
if you want to return a parseable JSON object, then write
render json: { some: 'json objects', should: 'go here' }
Also, not knowing what "mails" are, if you're trying to send emails that should be done with action mailer, and probably done as a part of committing the main model to the database (if you're creating a user and also trying to send an email, have a method as part of user creation that sends out the email).