I've written an app that contains an html text input:
<form method="POST" action="" enctype="multipart/form-data">
<input class="ocsp_override_box_input" type="text" id="ocsp_override" name="ocsp_override" placeholder="Override the AIA field with a URL here..." value="">
</form>
In the flask app, I access the data with the following:
ocsp_override = request.form.get('ocsp_override')
It works as expected and the rest of my code is able to use this string value and do things with it. So far, so good. The way the code works is that this field should be optional. If it is blank, then it is ignored. If data is filled in it, it runs some checks and then uses this override string later on.
The issue I'm finding is that if I complete the text form using flask dev, it works as expected, but when I reload the page and leave it blank, it appears to be caching the previous entry.
For instance, if I enter in http://example.com in the text field, the code will use that string. If I reload the page (not using F5, by reloading the get page so I can post again), and I leave the field blank, the code appears to be trying to use http://example.com again. What's weird is that if I try to print(request.form.get('ocsp_override')) then it shows nothing.
If I wait a length of time (I want to say 10 mins), and then try again, everything works as expected with the field blank.
Is there some kind of caching happening here and how can I force it to reload and be fresh every time?
You might try disabling autocomplete:
e.g.
<input class="ocsp_override_box_input" ... autocomplete="off">
And if that does not work, you can try adding a cache control header to the response to prevent the browser from caching the page:
response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
response.headers['Pragma'] = 'no-cache'
response.headers['Expires'] = '0'
return response
See this answer describing Cache-Control vs Pragma headers.
I am writing a tool to record and monitor downtime on a range of equipment.
I have my file structure as below:
File Structure
Sites is just a subfolder containing individual HTMLS for where the equipment is located.
Currently, flask runs webapp.py which contains:
>from . import app
>#app = (__init__.app)
>from . import views
>from . import ReportingTool
views.py has all of my #app.route's in it, up until the [site].html files. From there, on the [site].html file I ask for input from the user. I haven't started writing code to record the user input in any meaningful way, just want to get the data to a python script and commit them to variables. To this end, in the html file I have
<body>
<div class="menu">
<form method="post" enctype="multipart\form-data" action="{{ url_for('downTime') }}">
<fieldset class="datafieldset">
This then requests different data from the user in the form of multiple field sets as seen here: fieldsets
as you see in the code snippet above I set the action to be url_for('downTime'), downTime is a function in my python file ReportingTool.py. this throws out an error, "werkzeug.routing.exceptions.BuildError: Could not build url for endpoint 'downTime'. Did you mean 'supportguide' instead?" traceback
Is there something I need to add or specify on the html document to enable this page (and the other [site].html pages to call functions from the ReportingTool.py file? the #app.route that calls the [site].html file is this and that is called with a redirected from here I've only got it setup like that becuase I wanted the name for the site to appear in the address bar.
Thanks in advance.
I am not sure on steps to fix as I am kind of throwing myself in the deep end to learn basic coding by creating an application for my workplace to replace an excel spreadsheet I created.
You are not reaching the downTime function in the ReportingTool.py file. I suggest trying add_url_rule in your views.py by adding the /reported endpoint referencing the downTime function in ReportingTool.py. Something like this;
app.add_url_rule('/reported', 'ReportingTool.downTime', view_func=ReportingTool.downTime, methods=METHODS)
This answer is based on the responds for this question. You are trying to reach a function in a different file from your main view file. Assuming you are calling the page with the form from a function in the views.py file.
Solved with info from Kakedis' input, and the links they provided.
I added:
app.add_url_rule('/reported', 'ReportingTool.downTime', view_func=ReportingTool.downTime, methods=METHODS)
to webbapp.py, then:
#app.route('/reported')
def downTime():
try:
DTref = request.form['refDT']
except:
DTref = "No Reference"
print(DTref)
print("reported")
return(render_template("/UserRip.html"))
to ReportingTool.py
This now prints the above to console to confirm it's pulling the correct func and brings the user back to the starting page.
Is there a way I can modify the URL of the current page without reloading the page?
I would like to access the portion before the # hash if possible.
I only need to change the portion after the domain, so it's not like I'm violating cross-domain policies.
window.location.href = "www.mysite.com/page2.php"; // this reloads
This can now be done in Chrome, Safari, Firefox 4+, and Internet Explorer 10pp4+!
See this question's answer for more information:
Updating address bar with new URL without hash or reloading the page
Example:
function processAjaxData(response, urlPath){
document.getElementById("content").innerHTML = response.html;
document.title = response.pageTitle;
window.history.pushState({"html":response.html,"pageTitle":response.pageTitle},"", urlPath);
}
You can then use window.onpopstate to detect the back/forward button navigation:
window.onpopstate = function(e){
if(e.state){
document.getElementById("content").innerHTML = e.state.html;
document.title = e.state.pageTitle;
}
};
For a more in-depth look at manipulating browser history, see this MDN article.
HTML5 introduced the history.pushState() and history.replaceState() methods, which allow you to add and modify history entries, respectively.
window.history.pushState('page2', 'Title', '/page2.php');
Read more about this from here
You can also use HTML5 replaceState if you want to change the url but don't want to add the entry to the browser history:
if (window.history.replaceState) {
//prevents browser from storing history with each change:
window.history.replaceState(statedata, title, url);
}
This would 'break' the back button functionality. This may be required in some instances such as an image gallery (where you want the back button to return back to the gallery index page instead of moving back through each and every image you viewed) whilst giving each image its own unique url.
Here is my solution (newUrl is your new URL which you want to replace with the current one):
history.pushState({}, null, newUrl);
NOTE: If you are working with an HTML5 browser then you should ignore this answer. This is now possible as can be seen in the other answers.
There is no way to modify the URL in the browser without reloading the page. The URL represents what the last loaded page was. If you change it (document.location) then it will reload the page.
One obvious reason being, you write a site on www.mysite.com that looks like a bank login page. Then you change the browser URL bar to say www.mybank.com. The user will be totally unaware that they are really looking at www.mysite.com.
parent.location.hash = "hello";
In modern browsers and HTML5, there is a method called pushState on window history. That will change the URL and push it to the history without loading the page.
You can use it like this, it will take 3 parameters, 1) state object 2) title and a URL):
window.history.pushState({page: "another"}, "another page", "example.html");
This will change the URL, but not reload the page. Also, it doesn't check if the page exists, so if you do some JavaScript code that is reacting to the URL, you can work with them like this.
Also, there is history.replaceState() which does exactly the same thing, except it will modify the current history instead of creating a new one!
Also you can create a function to check if history.pushState exist, then carry on with the rest like this:
function goTo(page, title, url) {
if ("undefined" !== typeof history.pushState) {
history.pushState({page: page}, title, url);
} else {
window.location.assign(url);
}
}
goTo("another page", "example", 'example.html');
Also, you can change the # for <HTML5 browsers, which won't reload the page. That's the way Angular uses to do SPA according to hashtag...
Changing # is quite easy, doing like:
window.location.hash = "example";
And you can detect it like this:
window.onhashchange = function () {
console.log("#changed", window.location.hash);
}
The HTML5 replaceState is the answer, as already mentioned by Vivart and geo1701. However it is not supported in all browsers/versions.
History.js wraps HTML5 state features and provides additional support for HTML4 browsers.
Before HTML5 we can use:
parent.location.hash = "hello";
and:
window.location.replace("http:www.example.com");
This method will reload your page, but HTML5 introduced the history.pushState(page, caption, replace_url) that should not reload your page.
If what you're trying to do is allow users to bookmark/share pages, and you don't need it to be exactly the right URL, and you're not using hash anchors for anything else, then you can do this in two parts; you use the location. hash discussed above, and then implement a check on the home page, to look for a URL with a hash anchor in it, and redirect you to the subsequent result.
For instance:
User is on www.site.com/section/page/4
User does some action which changes the URL to www.site.com/#/section/page/6 (with the hash). Say you've loaded the correct content for page 6 into the page, so apart from the hash the user is not too disturbed.
User passes this URL on to someone else, or bookmarks it
Someone else, or the same user at a later date, goes to www.site.com/#/section/page/6
Code on www.site.com/ redirects the user to www.site.com/section/page/6, using something like this:
if (window.location.hash.length > 0){
window.location = window.location.hash.substring(1);
}
Hope that makes sense! It's a useful approach for some situations.
Below is the function to change the URL without reloading the page. It is only supported for HTML5.
function ChangeUrl(page, url) {
if (typeof (history.pushState) != "undefined") {
var obj = {Page: page, Url: url};
history.pushState(obj, obj.Page, obj.Url);
} else {
window.location.href = "homePage";
// alert("Browser does not support HTML5.");
}
}
ChangeUrl('Page1', 'homePage');
You can use this beautiful and simple function to do so anywhere on your application.
function changeurl(url, title) {
var new_url = '/' + url;
window.history.pushState('data', title, new_url);
}
You can not only edit the URL but you can update the title along with it.
Any changes of the loction (either window.location or document.location) will cause a request on that new URL, if you’re not just changing the URL fragment. If you change the URL, you change the URL.
Use server-side URL rewrite techniques like Apache’s mod_rewrite if you don’t like the URLs you are currently using.
You can add anchor tags. I use this on my site so that I can track with Google Analytics what people are visiting on the page.
I just add an anchor tag and then the part of the page I want to track:
var trackCode = "/#" + urlencode($("myDiv").text());
window.location.href = "http://www.piano-chords.net" + trackCode;
pageTracker._trackPageview(trackCode);
As pointed out by Thomas Stjernegaard Jeppesen, you could use History.js to modify URL parameters whilst the user navigates through your Ajax links and apps.
Almost an year has passed since that answer, and History.js grew and became more stable and cross-browser. Now it can be used to manage history states in HTML5-compliant as well as in many HTML4-only browsers. In this demo You can see an example of how it works (as well as being able to try its functionalities and limits.
Should you need any help in how to use and implement this library, i suggest you to take a look at the source code of the demo page: you will see it's very easy to do.
Finally, for a comprehensive explanation of what can be the issues about using hashes (and hashbangs), check out this link by Benjamin Lupton.
Use history.pushState() from the HTML 5 History API.
Refer to the HTML5 History API for more details.
Your new url.
let newUrlIS = window.location.origin + '/user/profile/management';
In a sense, calling pushState() is similar to setting window.location = "#foo", in that both will also create and activate another history entry associated with the current document. But pushState() has a few advantages:
history.pushState({}, null, newUrlIS);
You can check out the root: https://developer.mozilla.org/en-US/docs/Web/API/History_API
This code works for me. I used it into my application in ajax.
history.pushState({ foo: 'bar' }, '', '/bank');
Once a page load into an ID using ajax, It does change the browser url automatically without reloading the page.
This is ajax function bellow.
function showData(){
$.ajax({
type: "POST",
url: "Bank.php",
data: {},
success: function(html){
$("#viewpage").html(html).show();
$("#viewpage").css("margin-left","0px");
}
});
}
Example: From any page or controller like "Dashboard", When I click on the bank, it loads bank list using the ajax code without reloading the page. At this time, browser URL will not be changed.
history.pushState({ foo: 'bar' }, '', '/bank');
But when I use this code into the ajax, it change the browser url without reloading the page.
This is the full ajax code here in the bellow.
function showData(){
$.ajax({
type: "POST",
url: "Bank.php",
data: {},
success: function(html){
$("#viewpage").html(html).show();
$("#viewpage").css("margin-left","0px");
history.pushState({ foo: 'bar' }, '', '/bank');
}
});
}
This is all you will need to navigate without reload
// add setting without reload
location.hash = "setting";
// if url change with hash do somthing
window.addEventListener('hashchange', () => {
console.log('url hash changed!');
});
// if url change do somthing (dont detect changes with hash)
//window.addEventListener('locationchange', function(){
// console.log('url changed!');
//})
// remove #setting without reload
history.back();
Simply use, it will not reload the page, but just the URL :
$('#form_name').attr('action', '/shop/index.htm').submit();
With two <a>:
<a id="100" onclick="createTriggered(this.id)"<i></i> Click Link </a>
<a id="200" onclick="createTriggered(this.id)"<i></i> Click Link </a>
both linked to the same onClick javascript function:
<script type=text/javascript>
$SCRIPT_ROOT = {{ request.script_root|tojson|safe }};
function onClick(id){
var data = $.getJSON($SCRIPT_ROOT + '/triggered', {a:id} );
window.alert({{ "session.keys()" }});
}
</script>
This javascript function takes the clicked <a> id and sends it to flask function:
#app.route('/onClick')
def onClick():
session['a_id'] = request.args.get('a')
return ('ok')
After Flask function gets id it updates session object creating a new key session['a_id'].
Finally javascript window.alert is used to check if the session object has the new 'a_id' key which should be already set by Flask function. When window.alert pops up it shows that the new key is missing. Refreshing the page and re-clicking the <a> link will pop up the window.alert() again but this time showing the new session['a_id'] key is there. It looks like the update of the session object is lagging behind. I have to refresh the page in order for the browser to pick up the change made by Flask function. Is there a way to assure that the update made by the Flask function to the session object is reflected immediately?
Finally, since I am updating the session object which is global to the entire session I really don't want to return any template or to redirect to another link. All I want is Flask function to set the session variables so it could be used somewhere down the logic. Would it be ok to return a dummy string from Flask function in this case?
It looks like the update of the session object is lagging behind.
It is not lagging. The issue is that originally you don't have anything in your session, thus your HTML page and your javascript is equivalent to
window.alert().
After you update your session, re-render the page update the javascript code to window.alert('a_id').
Is there a way to assure that the update made by the Flask function to the session object is reflected immediately?
You can examine your javascript callback to check the cookie return. The cookie is encrypted, so you won't see the value unless you know how to decrypt it. It is not recommended to do that. However, at the very least you can see the value of the cookie is changed.