I'm building a sort-of clone of CoverItLive in Rails 3.1 and want to have the stream of comments automatically update. I'm using a partial in the view to display comments. There's a lot of info out there on doing UJS and AJAX wit forms or buttons or links in Rails, but I can't find any specific examples for what I need to do.
I'm assuming that .ajax() is the best approach, but I've never used it before and not sure if I need to provide .js.erb files when using this particular function? Could I just have the controller send JSON back to the client and go from there, or is there a better approach in rails?
This is what I'm thinking so far, based on what I read at another question:
setInterval(function() {
$.ajax({
type: 'GET',
url: ''<%= comments_path(:json) %>'',
data: {
data: "comments_data"
},
cache: false,
success: function(result) {
if (result == "true"){
alert("true");
}else{
alert("false");
}
}
});
}, 3000);
As an alternative you should look into Private Pub, a gem that Ryan Bates has put togeather. See a screencast about it on railscasts.
The trouble with your solution is now often you server will be hit unnecessarily, i guess it depends on the number of concurrent users you thing will be viewing this page.
if you do go down your route the .js.erb could just have a somthing like this in it:
$('#id_of_area_to_replace').html("<%= escape_javascript(render"comments/index") %>")
This would replace the whole area else you could just append new comments to the bottom of the area
Related
I use the dynamic source for vue-webpack images in nuxt :src="require('path/to/image' + dynamic.variable)" in my project navbar. If the users substitute their image through a form which refetches their information and deletes their previous image I get a webpack error module (img) not found (it does not find the new one): is there a way to solve this, like wait for webpack HRM to finish?
I tried setting up a setTimeout() of one second before user re-fetch and it works, but I don't like a random waiting, I'd use a promise or a sync dynamic, the point is webpack hot reload is not controlled by my functions.. I also tried with setting the dynamic path as a computed: but it doesn't fix.
My image tag:
<img v-if="this.$auth.user.image" class="userlogo m-2 rounded-circle" :src="require('#assets/images/users/' + this.$auth.user.image)" alt="usrimg">
My Useredit page methods:
...
methods: {
userEdit() {
//uploads the image
if (this.formImageFilename.name) {
let formImageData = new FormData()
formImageData.append('file', this.formImageFilename)
axios.post('/db/userimage', formImageData, { headers: { 'Content-Type': 'multipart/form-data' } })
// once it has uploaded the new image, it deletes the old one
.then(res=>{this.deleteOldImage()})
.catch(err=>{console.log(err)})
}else{
this.userUpdate() //if no new image has to be inserted, it proceeds to update the user information
}
},
deleteOldImage(){
if(this.$auth.user.image){axios.delete('/db/userimage', {data: {delimage: this.$auth.user.image}} )}
console.log(this.$auth.user.image + ' deleted')
this.userUpdate() // it has deleted the old image so it proceeds to update the user information
},
userUpdate(){
axios.put(
'/db/user', {
id: this.id,
name: this.formName,
surname: this.formSurname,
email: this.formEmail,
password: this.formPassword,
image: this.formImageFilename.name,
})
.then(() => { console.log('User updated'); this.userReload()}) // reloads the updated user information
.catch(err => {console.log(err)} )
},
userReload(){
console.log('User reloading..')
this.$auth.fetchUser()
.then(() => { console.log('User reloaded')})
.catch(err => {console.log(err)} )
},
}
...
the problem happens after "console.log('User reloading..')" and before "console.log('User reloaded');", it is not related to the file upload nor the server response. I broke a single function in many little ones just to check the function progression and its asynchronous dynamics but the only one that is not manageable is the webpack hot reload :/
I'd like the users to upload their images and see their logo in the Navbar appear updated after submitting the form.
First of all, as somebody told you in the comments, webpack hmr shouldn't be used for production.
In Nuxt, everything that you reference from the assets folder will be optimized and bundled into the project package. So the ideal use case for this folder is all assets that can be packaged and optimized, and most likely won't change like fonts, css, background images, icons, etc.
Then, require is called only once by webpack when it is either building the site for local development or building the site for generating a production package. The problem in your case is that you delete the original file while you're in development and webpack tries to read it and fails.
In the case of these images that the user uploads, I think you should use the static folder instead and instead of using require you'll have to change the :src with
:src="'/images/users/' + this.$auth.user.image"
Let me know if this helps.
Okay, I probably solved it.
HMR: you are of course right. Thank you for pointing out, I am sorry, I am a beginner and I try to understand stuff along the way.
Aldarund, thank you, your idea of not changing the path and cache it client side.. I am too noob to understand how I could implement it ( :) ) but it gave me a good hint: the solution was to keep the image name as the user id + the '.png' extension and to manage the image with jimp so that the image name, extension and file type are always the same, and with or without webpack compiling the new path, I always have the correct require().
Jair, thank you for the help, I didn't follow that road, but I will keep it as a second chance if my way creates errors. Just to be specific: the error comes when it does not find -and asks for the name of- the NEW image, not the OLD one, as I wrote in my question: it happens because the fetchUser() functions reloads the user information including the new image name.
Do you guys see any future problems in my methodology?
Really thank you for your answers. I am learning alone and it's great to receive support.
I'm using Bootstrap 3.2.0 and jQuery 2.1.1.
I've implemented typeahead search suggestions and now wanted to go a step further. I am using the remote method and was hoping to send more than just the query to the PHP that will run a SQL script:
$(function() {
var productEngine = new Bloodhound({
datumTokenizer: function (datum) { return Bloodhound.tokenizers.whitespace(datum.value); },
queryTokenizer: Bloodhound.tokenizers.whitespace,
limit: 10,
remote: { url: 'php/product_suggest.php?storeid='.concat(localStorage.getItem('store_id'), '&query=%QUERY') }
});
productEngine.initialize();
$('input#product_suggest').typeahead(null, {
displayKey: 'value',
source: productEngine.ttAdapter()
});
});
I've also tried building the URL and saving as a variable. Then attempting to call that variable in the remote.
remote: { url: builtURL }
As I don't particularly know how this url is being parsed and used or how the %QUERY is being added, I'm assuming my issue lies in my lack of knowledge around how typeahead is processing this.
I thought this would be a fairly common request, but Google has let me down. Anyone have any suggestions or can point me towards examples of sending additional info with a typeahead query?
I'm trying to automate an application that uses form security in order to upload a file and then scrape data from the returned HTML.
I started out using the solution from this question. I can define my steps and get through the entire workflow as long as the last step is rendering the page.
Here are the two steps that are the meat of my script:
function() {
page.open("https://remotesite.com/do/something", function(status) {
if ('success' === status) {
page.uploadFile('input[name=file]', 'x.csv');
page.evaluate(function() {
// assignButton is used to associate modules with an account
document.getElementById("assignButton").click();
});
}
});
},
function() {
page.render('upload-results.png');
page.evaluate(function() {
var results = document.getElementById("moduleProcessingReport");
console.log("results: " + results);
});
},
When I run the script, I see that the output render is correct. However, the evaluate part isn't working. I can confirm that my DOM selection is correct by running it in the Javascript console while on the remote site.
I have seen other questions, but they revolve around using setTimeout. Unfortunately, the step strategy from the original approach already has a timeout.
UPDATE
I tried a slightly different approach, using this post and got similar results. I believe that document uses an older PhantomJS API, so I used the 'onLoadFinished' event to drive between steps.
i recomend you use casperjs or if you use PJS's webPage.injectScript() you could load up jquery and then your own script to do form input/navigation.
I'm having a bunch of problems getting jQuery's .on to work with my Rails ajax link.
Specifically, I've got this link:
<div id="item_7_tools" class="item_tools">
<a rel="nofollow" id="book_item_7" data-remote="true" data-method="post" class="book_link" href="bookings">Book this item</a>
</div>
I've trimmed some of the text in the HTML, but suffice to say that that, and my controller response work.
I click "Book this item", it goes off to the controller, the controller does its magic, and sends back my partial that replaces the contents of that div.
So I'm now trying to replace the contents with an ajax spinner while the loading is working, and that's where its going pear-shape.
I'm trying this initial bunch of jQuery code just to make sure I've got my javascript working:
$('div.item_tools')
.on('click', 'a', function() {
console.log("clicky click")
})
.on('ajax:beforeSend', "a", function() {
console.log('the a in div.item_tools is sending its ajax command');
})
.on('ajax:complete', "a", function() {
console.log('ajax request completed');
})
My understanding of that, is that when I then click any link (a) that lives within an element with the item_tools class, it will bubble up to this function, and then log the message into the console. Similarly, a link that has triggered an ajax request will get the same treatment...
(And assuming I can get that to work, then I'll go to work doing the ajax loader spinner).
The behaviour I'm seeing instead, is that when I click the link, there are no messages appearing in my console (trying this on both firefox and chrome), and my ajax link goes off and does its stuff correctly. Just completely ignoring the javascript...
Is this because my clicking the ajax link somehow has blocked the click event from bubbling up? I know that there's a way to do that, but I don't think I've done it anywhere knowingly. Unless OOTB rails/ujs does that?
So my questions:
Is there a way to tell what has had a binding attached to it?
What am I doing wrong with my javascript?
Thanks!
I use this all the time... and it seems to work fine.
Have you tried adding one that's .on('ajax:success')?
Besides that try putting the . for each line on the previous line...? It's possible that it gets to $('div.item_tools') and then auto-inserts a semi-colon as per javascript's standard... Although if that were the case I'd expect it to give you a JS error about the . on the next line. In any case try changing it to:
$('div.item_tools').
on('click', 'a', function() {
console.log("clicky click")
}).
on('ajax:beforeSend', "a", function() {
console.log('the a in div.item_tools is sending its ajax command');
}).
on('ajax:complete', "a", function() {
console.log('ajax request completed');
})
If worse comes to worse try just doing:
$("a").on("ajax:success", function(){
console.log('ajax:success done');
})
And see if it works without the event delegation...
Then change it to this:
$(document).on("ajax:success", "a", function(){
console.log("ajax:success with delegation to document");
})
And see if delegation works all the way up to document instead of just your item_tools
Are you sure that you've named everything right? it's div.item_tools a in your markup?
Turns out that the javascript was being triggered before the DOM had loaded, which meant that stuff weren't being bound...
$(function () {
$('div.item_tools')
.on('click', 'a', function itemToolsAjaxy() {
console.log("clicky click");
})
.on('ajax:beforeSend', "a", function() {
console.log('the a in div.item_tools is sending its ajax command');
$(this).closest('div').html('<img src=/assets/ajax-loader.gif>');
})
});
Added the $(function()) right at the beginning and it delayed the binding until after the DOM had loaded, and then it started working.
Figured this out by using the Chrome developer tools to stick a break on the div.item_tools selector and watched as the browser hit that even before the DOM had been loaded. /facepalm
(I removed the .on('ajax:complete') callback, because it turns out that there's a known limitation where the original trigger element no longer exists because it had been replaced, so there's nothing to perform the callback on. Not relevant to my original problem, but I thought I'd mention it.)
As far as i'm aware, you can either do ajax stuff 2 ways:
By using :remote => true
By using jQuery's $.ajax (or $.post).
With number 2, make sure to change your href='#'
My suggeston is to remove the :remote => true and manually make a jQuery ajax call. That way you can use beforeSend, complete, etc.
If i'm way off track here, someone please help clarify things for me as well.
i have already read this topix : "http://stackoverflow.com/questions/4820637/how-do-i-perform-an-ajax-request-to-the-create-action-on-loading-a-page-in-rails" but it doesn't respond to the question..
I want to make a loading animation into my rails 3 app cause the server takes time to send email and do some other calculation so the user experience is not so good...
I have read this tutorial : http://www.marketingformavens.com/blog/create-a-page-loading-animation-with-ruby-on-rails-and-ajax but it's for rails2 (remote_function doesn't exist anymore in rails 3).
I wonder if someone can tell the way i should do so :
-> having a nice animation loaded onto the screen when the user click on an action (like create, or update)
Thank's a lot.
Hope to find a answer...
If I understand you want to load an animation while your action is done in ajax. Just use the jQuery API to call your controller actions in Ajax and use callbacks to stop your animations :
$("#myaction").click(function(){
//write your animation code here
$.ajax({
url: "http://localhost:3000/yourcontrolleraction",
dataType: "json",
type: "POST",
processData: false,
contentType: "application/json",
data: yourdata
success: function(){
//stop your animation here
}
})
});
For more on using jQuery Ajax with Rails I suggest your read this excellent post : http://blog.project-sierra.de/archives/1788