I have an unusual problem that I can't wrap my head around and figure what is causing this and how to tackle it.
I've created a webpage that allows image uploads to the server! After the user uplaoded an image the host of the page receives an e-mail with the path to the uploaded image - really straight forward.
In the e-mail for instance a url like this is coming in.
https://www.something.com/uploads/FB_IMG_1525868856883.jpg
I can open that in Safari on Mac, I can open that in some cases in Chrome Incogntio, but it never renders in Internet Explorer or normal Chrome Window (in Incognito it does)
In the image you see something weird happening. In Incognito a different source is rendered than in a normal chrome window. (this is btw. not a caching issue)
you also see the page-title of the actual website resolved in the normal window, but not in incognito.
Why is that happening? What could cause that? is that some server setting? Some react setting I have to set?
I'm posting this in case someone else runs into it as well. I ran into this same issue where 500 kept happening for me and I knew it was not the extensions.
What fixed it for me:
Open Developer Tools in Chrome
Navigate to Applications Tab
Click "Clear Storage
Click Clear Site Data
As Nitish Phanse said, it is because the page is cached. Turning off browser caching will solve it.
I faced a similar problem, when any of the changes in CSS were not being reflected in the webpage, because the cached version was being used by chrome. However, the changes were visible in other browsers and devices. Turning off caching in chrome solved this problem for me.
I prefer to use incognito mode when developing website because when browsing normally the files are cached, thus, not reflecting the changes you made. When you use incognito mode, fresh cache and cookies are stored and the cache and cookies are disposed when you close the incognito window. Another plus point of using incognito mode for testing is that, it disables all the plugins, unless you explicitly enable them.
You might want to check out this question on Quora for further details on why to use incognito mode when developing websites.
Seems like you use quite amount of Chrome plugins. In Incognito-mode those are disabled by default. Try remove/disable AdBlock etc. stuff which blocks scripts and disallow them from running.
Makes quite a lot sense why they run in other browsers too.
I strongly recommend to NOT use plugins when you do web development. You might see different kind of behaviour with same code as user who do not use them. Only use this approach if you especially wan't to develop under certain conditions.
As most people suggest, it definitely sounds like a caching issue. Incognito doesn't load the page with cache. You could ctrl+f5 the page (reload without chache) and see if it still does it. If the caching itself proves to be an issue, you could add a ghost/phantom string (I don't know if that's the actual correct terminology). Basically you add,
<?php echo '?'.date('Y-m-d H:i:s'); ?>
at the end CSS or JavaScript import (whatever may cause the issue). I.e,
<script src="/js/regexps.js<?php echo '?'.date('Y-m-d H:i:s'); ?>" type="text/javascript"></script>
What this does, is that it will prevent people from caching your file, since the name of that file will change by the second. This way, you make sure that if you make changes to files that are often cached, that everyone gets the uncached changes as you update your CSS/JavaScript or whatever. This is very useful for files where you make JavaScript check for instance, in case you make changes to some regex etc.
I have a quite large app build using phonegap and jQuery mobile. I have about 5 pages withing the one HTML page (as per jQuery mobiles navigation system) all sharing one main JS file, which has 3400 lines of JS code.
The app has ran slower over the development period, and I Was wondering if it would make a difference splitting the app up into seperate HTML files and having them load into the DOM?
And secondly, would it also be worth splitting the javascript up so only javascript needed on the page is currently loaded with the page?
Like shall I have the whole 3400 lines of code loaded on device ready? or inject needed JS along with the page?
Yep as Nathan said I think you already know the answer.
I'd definitely recommend splitting your application into separate HTML pages and JavaScript, and loading the JavaScript only as and when you need it. I've heard people recommend a single-page architecture approach, although the difference there is that the HTML pages and JavaScript are injected in and loaded as and when they are needed.
See part 4 here in this PhoneGap tutorial for more information on properly implementing a single-page architecture.
It's not a good idea to load everything into memory at the start... it's an inefficient use of resources - as you can see from the slow performance.
And having separate HTML and JavaScript files should also be a lot easier to manage and understand as well.
After loading the too much data ~(250 records in listview) in jquery mobile page DOM. The navigation sytem transits very slow. I have tried verious tricks but unsuccessful. finally, I got the exceptable performance of navigation by applying below tricks.
Try to remove/hide the populated data from DOM when trying to change page.
when come back to page. repopulate it.
http://www.puppykisses.org/
i made a WordPress page for a client, and for some reason it is taking over a minute to load the page. The only thing that I could think of being the problem is the amount of photos that he inserted into the slider up top on the home page. It looks like all those pictures need to load before anything else pops up. But then I click on Contact or any other page that has no real images to speak of, and the problem is still there. Just wondering if anyone can point me in the right direction to fix this. thanks!
Like #David said, its the initial request (the source for the page) that is giving you the issues. This means it is unlikely an issue with hosting, and most likely an issue with your code. I would go through any plugins you have installed and disable them one-by-one, and slowly start commenting out your own custom dynamic code bit by bit, till you see what is taking so incredibly long. Then rewrite/excise that code from the site.
Start With the Basics
Keep the number of WordPress plugins you use to a minimum
Get a Proper Hosting Provider
Remove Unnecessary Code From WordPress Header -> http://goo.gl/yfRcF
Use firebug and click Network tab to check loading speed for each files
Check Suggestion how to improve website speed -> http://goo.gl/FtiX3
Install WP Super Cache plugin -> http://wordpress.org/extend/plugins/wp-super-cache/
*If you use gallery try to use image thumbnail rather than load whole images size
Some years ago I decided I could bypass all the browser inconsistencies by producing sites entirely in Flash. Doesn't look such a good decision now so I'm re-writing my semi-CMS framework in php, javascript/jQuery and HTML. One aspect of my Flash sites which I am very pleased with is the ability to load all pages or states in the background so the user rarely requests a page that isn't already loaded. When that does happen I can display a progress bar. In AJAX I can't display progress but I also found a significant difference I hadn't anticipated. In Flash I load the .swf for page 1 completely, before starting to load page 2. That means everything including images etc. In AJAX I can't see a way to do that. I can check that the HTML file itself has completed loading, but not that all its images have loaded before loading the next HTML file. Is it possible?
If you're looking for an HTML5 solution rather than just an AJAX solution you might want to investigate the Application Cache. There is a progress event which you could hook into, though it possibly doesn't get into the level of detail you need. As far as I'm aware, resources will start downloading in the order they're listed in the manifest file.
What Firefox add-ons do you use that are useful for programmers?
I guess it's silly to mention Firebug -- doubt any of us could live without it. Other than that I use the following (only listing dev-related):
Console2: next-generation error console
DOM inspector: as the title might indicate, allows you to browse the DOM
Edit Cookies: change cookies on the fly
Execute JS: ad-hoc Javascript execution
IE Tab: render a page in IE
Inspect This: brings the selected object into the DOM inspector
JSView: display linked javascript and CSS
LORI (Life of Request Info): shows how long it takes to render a page
Measure IT: a popup ruler.
URL Params: shows GET and POST variables
Web Developer: a myriad of tools for the web developer
Here are mine (developer centric):
FireBug - a myriad of productivity enhancing tools, includes javascript debugger, DOM inspector, allows you to edit the CSS/HTML on the fly which is highly valuable for troubleshooing layout and display problems.
Web Developer - again another great developer productivity tool. I mostly use it for quickly validating pages, disabling javascript (yes I disable javascript sometimes, don't you?), viewing cookies, etc.
Tamper Data - lets you tamper with http headers, form values, cookies, etc. prior to posting back to a page, or getting a page. Incredibly valuable for poking and prodding your pages, and seeing how your web app responds when used with slightly malicious intent.
JavaScript Debugger - has a few more features than javascript debugger provided by firebug. Although I must admit, I sparingly use this one since firebug has largely won me over.
Live HTTP Headers - invaluable for troubleshooting, use it frequently. Lets you spy on all HTTP headers communicated back and forth between client and server. It has helped me track down nefarious problems, especially when debugging issues when deploying your web app between environments.
Header Spy - nice addon for the geeky types, shows you the web server and platform a web site runs on in the status bar.
MeasureIt - I don't use this all too frequently, but I've still found it valuable from time to time.
ColorZilla - again, not something I use all that frequently, but when I need it, I need it. Valuable when you want to know a color and you don't want to dig through a CSS file, or open up a graphics editing app to get a color embedded in some image.
Add N Edit Cookies - this has been a great debugging tool in web farms where the load balancer writes a cookie, and uses the cookie value to keep your session "sticky". It allowed me to switch at will between servers to track down problems on specific machine. Also a good tool if you want to try to mess with a site that uses cookies to track your login status/account, and you want to see how your code responds to malformed or hacked info.
Yellowpipe Lynx Viewer Tool - yeah I know what your thinking, lynx, who needs it, its so 1994. But if you are developing a site that needs to take web accessibility into account (meaning accessible to users with visual impairments who use screen readers), or if you need to get a sense of how a web spider/indexer "sees" your site, this tool is invaluable. Granted, you could always just go out and grab Lynx for yourselfhere's the windows xp port that I use.
I've got a handful of other addons that I've used from time to time that I'll just quickly mention: FireFTP (one I installed wasn't stable and I've not tried a newer release), Html Validator (also found this one unstable, least back when I installed like a year ago), IE Tab (I usually just have both IE and FireFox open concurrently, but that is just me, I know many others that find this addon useful).
I'd also recommend the Web Developer extension by Chris Pederick.
As far as web development, especially for javascript, I find Firebug to be invaluable. Web developer toolbar is also very useful.
The ones I have are...
Y-SLow
Live Headers
Firebug
Dom Inspector
One that wasn't mentioned yet is this HTML Validator extension that I found very useful.
#Flávio Amieiro
MeasureIt is an unnecessary extension to have if you install the Web Developer Toolbar. Web Developer Toolbar includes a ruler as one of its features. Under the "Miscellaneous" category for Web Developer click the option "Display Ruler" to use a ruler identical to the MeasureIt one.
That will allow you reduce the number of extensions needed by at least one.
Firefox addons:
FireBug:helps web developers and designers test and inspect front-end code. It provides us with many useful features such as a console panel for logging information, a DOM inspector, detailed information about page elements, and much, much more.
Web Developer-gives you the power disable CSS, edit CSS on the fly, measure certain areas of a page and much more.
ColorZilla
Just click on the icon, hover over the area you'd like to know the hex color for, and click.
Window Resizer
to make sure the layout is displayed properly in the standard resolutions of today.
Total Validator
validating websites much easier by checking HTML, links, CSS and doing a lot more.
Web Developer for web development. Scribefire if you're a blogger-progammer
For web developing I use the Web Developer Toolbar, CSS Viewer and MeasureIt.
But I'm really not one of those who has a thousand of extensions to do everything. I like to keep things simple.
EDIT: Thanks to Dan's answer I don't need MeasureIt anymore. Can't believe I've never seen that! I guess I'll just have to pay more atention to this WebDeveloper toolbar.
Adding to everyones lists, Tamper Data is quite useful, lets you intercept requests and change the data in them.
It can be used to bypass javascript validation and check whether the server side is doing its thing.
I use Web Developer, it's a real time saver.
+1 for LORI ("life-of-request-info"). It's a very convenient alternative for rough measurements of the load time of a particular web page -- the kind of thing that you might otherwise use an external stopwatch for.
New Tab Homepage. Combined with a "speed dial"-type homepage (a personal, fast-loading page of links that you use frequently), helps you get where you're going faster when you open a new browser tab.
LastTab. Changes the behavior of Ctrl+Tab to let you navigate back and forth between your most-recently-used tabs with repeated presses of Ctrl+Tab, the same way that Alt+Tab works in Windows. Also provides a nice view of all open tabs while Ctrl is still being held down for easy navigation. (The resultant behavior is very similar to the Ctrl+Tab behavior in recent releases of Visual Studio.)
FireFTP is good for grabbing/uploading any necessary files.
I find Hackbar to be quite useful. Very useful if you want to edit the querystring part of the url, to test for vulnerabilities, or just general other types of testing where you might end up with complicated query string values.
I was learning DOM inspector, but I've switched to Firebug.
Some of which has been missed above are here
Load Time Analyzer – View detailed graphs of the loading time of web pages in firefox. The graphs display events like page requests, image loading times etc.
Poster – A must have tool for web developers enabling them to interact with web services and other web resources.
Aardvark – A cool extension for web developers and designers, allows them to view CSS attributes, id, class by highlighting page element individually.
Fiddler is a really great debugging proxy. Think of it as a more powerful version of the "Net" panel in Firebug or the Live HTTP headers.
It used to be an IE-only extension, now it also has hooks into Firefox.
Groundspeed, is useful for testing server side code. It was created for input validation tests during pentest, but can be useful for any test that require manipulating input (similar to TamperData).
It lets you control the form elements in the page, you can change their type and other attributes (size, lenght, javascript event handlers, etc). So for example you can change a hidden field or a select to a textbox and then enter any value to test the server response and stuff like that.