I dont understand well of active storage documentation. I am using <%= image_tag current.user.avatar.variant(resize: "600x400") %> this in view but so slow in rendering while calling 10 images in index or show from s3. What is difference of variant and service_url? I just want to load images faster in rendering with caching. what are the options?
Related
Using 2sxc on DNN, I have a website that uses SVGs for icons in content types. The client wants to be able to upload the SVG icons to 2sxc via a Link field but then instead of rendering <img src="#Content.SVG" />, they want it to render the source code of the SVG (so we could manipulate the fill color via CSS). Is this even possible and how could it be done?
Basically 2 steps
Get the real file name using 2sxc and DNN
Then load the file as a string using normal .net stuff System.IO and add it to your html - https://learn.microsoft.com/en-us/dotnet/api/system.io.file.readalltext?view=netframework-4.5.1
ca. like this
<div>
#Html.Raw(System.IO.File.ReadAllText(fileName)
</div>
Some examples of how to do this can be found below
Using the fetch API
How to convert image (svg) to rendered svg in javascript?
Older methods such as XMLHttpRequest or jQuery
Include SVG files with HTML, and still be able to apply styles to them?
Using D3
(Embed and) Refer to an external SVG via D3 and/or javascript
Using a custom JS library
One example: SVGInjector
Interestingly Dnn is doing this nowadays and you can look at the code here. If you ignore the caching, you might be able to do similar in a View.
https://github.com/dnnsoftware/Dnn.Platform/blob/0d3b931d8483b01aaad0291a5fde2cbc0bac60ca/DNN%20Platform/Website/admin/Skins/Logo.ascx.cs#L123
And that is called from above, see ~line 71, so they are doing a real inject of the file contents to inline. Obviously caching file-access stuff should be a priority for caching if the website is high-traffic, but otherwise it is not needed or at least secondary.
In my hybrid Android app I use inline SVG to display images that are large (of the order of 2Mb) and complex (several hundred SVG elements per image). When I need to change the image I do the following
var puzzle = document.createElementNS(SVGNS,'svg'),
kutu = document.getElementById('kutu');
puzzle.id = 'puzzle';
puzzle.setAttribute('preserveAspectRatio','none');
puzzle.setAttribute('width','100vw');
puzzle.setAttribute('height','85.5vh');
puzzle.setAttribute('xmlns',SVGNS);
puzzle.setAttribute('xmlns:xlink',XLINK);
puzzle.setAttribute('fill-rule','evenodd');
puzzle.setAttribute('clip-rule','evenodd');
puzzle.setAttribute('stroke-linejoin','round');
puzzle.setAttribute('stroke-miterlimit','1.414');
puzzle.setAttribute('viewBox','0 0 1600 770');
puzzle.innerHTML = SVG;
//SVG here is the SVG image content shorn off the outer <svg>..</svg>
if (0 < kutu.children.length) kutu.children[0].remove();
//remove old image, iff any
kutu.appendChild(puzzle);
//append the new image
While this is working the process of displaying the new image is slow. I suspect it is because of the innerHTML assignment above. Recreating through a sequence of createElementNS, puzzle.àppendChild would require me to first parse the incoming raw SVG content etc. Is that the way to go or would there be a faster way to display the content.
Once again for clarity - SVG here is the content of the new SVG image to be displayed shorn of its outer <svg>...</svg> wrrapper.
Just a side note it would probably be better to use setAttributeNS in place of setAttribute for consistency purpose since createElementNS is used, though it might not make a difference in speeding up the SVG image change.
In the case of a native app, a tool like the Android Profiler if using Android Studio 3.0 and higher can be used to analyze performance bottleneck. However since your app is a hybrid app, some sort of performance profiler that's applicable to the hybrid app (Whether it's Ionic or Cordova, etc.) can help to pinpoint where your performance bottleneck is.
Since your app is a hybrid, without knowing the resource capacity of your android app session, the guess is it seems to be a possible cause that it calls something like .setAttribute to set session-level attributes on the fly during the change of the image and the session resource might not be enough, and also the DOM has to perform .innerHTML and appendChild, which are dynamic operations. DOM manipulation is known to be slow.
Conversion of attributes of all the SVGs and store the result in some sort of storage or cache, and when needed, call it from the persistent storage or cache might be helpful.
Or consider using AngularJS to do the SVG change beforehand and preload the SVG images, refer to easily preload images in your Angular app. Here is another similar code to yours except it's using AngularJS to add SVG for starters.
Another simpler way, without changing your code, if you could minify the incoming SVGs beforehand, is to use SVG Optimizer or SVGO, a node.js open source project to compress your SVGs. Quoted from the SVGO link it says:
"SVG files, especially those exported from various editors, usually contain a lot of redundant and useless information. This can include editor metadata, comments, hidden elements, default or non-optimal values and other stuff that can be safely removed or converted without affecting the SVG rendering result." Although the performance gain might not be obvious going this route.
I am inspecting a portal's page for loading of images ,its loading very slow.
We pick images from a filesystem , images name from database and read them, create a list and show results using a4j:mediaOutput tag. but the images are being loaded very slowly.
http://www.easyrenting.com/list-detail/3bhk-ardee-city-sector-52/6263
The first problem I see is that all your pictures are high-res (1800px x 2400px).
You really should create thumbnails server side to meet your view requirement and load images according of the size you want to show on the client size.
Have you only verified that your web page weight about 6.5MB including all images? (Check with Firebug).
I would recommand you a custom servlet like this one FileServlet supporting resume and caching with GZIP, and create a URL pattern according to load full res or thumbnail depending of the requirement.
There is no problem using the a4j:mediaOutput tag.
The images are getting loaded slowly because the size is too large, you need to find out a way to optimize the image size. Probably you can re-size the images before saving it to your file system.
Unless you are giving the zoom functionality, you do not need these big images.
That should help!
i want to know wheter open laszlo has data uri feature. The following example will show a red dot where the red dot is an image and base64 data is passed to it. Is it possible to do something like this?
example is given below
<div>
<p>Taken from wikpedia</p>
<img src="data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot" />
</div>
You are referring to Data URLs as specified in RFC 2397. That feature not supported in OpenLaszlo, and it only would be relevant for DHTML applications anyway. For the SWF runtime, images can be compiled into a SWF file as static resources, increasing the file size and reducing the number of requests needed to send to the server.
There are size limitations for inline images as well. Browsers are only required to support URLs up to 1,024 bytes in length, according to the above RFC. Browsers are more liberal in what they'll accept, however. Opera limits data URLs to about 4,100 characters. Firefox supports data URLs up to 100K, which means you should only use the technique for small to medium size images.
Even though Data URLs are not supported in OpenLaszlo, a similar - and in my eyes - more powerful option is available. The automatic generation of a CSS sprites for images you add as static resources. When you select the 'Use master sprite' compile option, the OpenLaszlo compiler will create one PNG sprite map containing all those static resources.
Here is an example of the master sprite PNG for the OpenLaszlo weather widget. Instead of making multiple requests to download the individual images, the browser just has to make one request.
I want to retrieve a user profile picture. How do i do it? Could you please share a code snippet? Im using Liferay 6.0.6. It has only user.getPortraitId() and no user.getPortraitURL(). So once i get the portrait id inside a JAVA class, what do i do with it?
See the implementation of UserConstants.getPortraitURL(...)
https://github.com/liferay/liferay-portal/blob/master/portal-service/src/com/liferay/portal/model/UserConstants.java
On this approach you can get the image url.
If you need the image object, you can load it with ImageLocalServiceUtil:
long portraitId = user.getPortraitId();
Image image = ImageLocalServiceUtil.getImage(portraitId);
There are at least two options on rendering portraits in JSP:
<img src="<%= themeDisplay.getPathImage()%>
/image_gallery?img_id=<%= image.getImageId()%>&t=
<%= ImageServletTokenUtil.getToken(image.getImageId())%>">
<img src="<%= themeDisplay.getPathImage() %>/user_portrait?img_id=<%=id %>">
The first approach contains additional security aspect based on security token which you may or may not find relevant to your needs.