I am using spark as the backend to a project I am working on. I noticed that spark has the ability to serve templated html, using a templating engine such as velocity, freemaker, etc.
However, this isn't quite what I want. Instead of serving an html template, I would like to serve a plaintext file, while still allowing me to insert parameters where needed. For context, I am trying to allow the user to download code examples based on the parameters they have supplied.
Does anything like this exist, or do I need to essentially build the desired file's content and return it as a string?
Example of what I am trying to do
// example.java
public class Example {
public static void main(String [] args) {
System.out.println( {{ param }} );
}
}
So this ^ would be the plain text template that I am attempting to serve... "param" would be passed to the backend via http request, and inserted into the file. Then I would serve the file to the frontend.
So, (as mentioned in the comment :), glad it helped) you can serve this content as HTML page (then you can use template manager) containing only this plaintext content only. Only exception will be the extension which will be .html instead of .java if the user saves the file.
You could declare a route whose return type is 'text/plain'
get(Main.API_PUBLIC + "/sourcecode", (req, res) -> {
res.status(200);
res.type("text/plain");
return " /* This will be the code snippet you'll be returning */ ";
});
Another alternative would be putting your source code files into the static files directory and link to them in your html.
Related
I am trying to select a local json file and load it in my blazor client component.
<input type="file" onchange="LoadFile" accept="application/json;.json" class="btn btn-primary" />
protected async Task LoadFile(UIChangeEventArgs args)
{
string data = args.Value as string;
}
P,S I do not understand , do i need to keep track both the name of the file and the content when retrieving it ?
I guess you're trying to read the contents of a JSON file on the client (Blazor), right? Why not on the server !?
Anyhow, args.Value can only furnish you with the name of the file. In order to read the contents of the file, you can use the FileReader API (See here: https://developer.mozilla.org/en-US/docs/Web/API/FileReader). That means that you should use JSIntrop to communicate with the FileReader API. But before you start, I'd suggest you try to find out if this API have been implemented by the community (something like the localStorage, etc.). You may also need to deserialize the read contents into something meaningful such as a C# object.
Hope this helps...
There is a tool that can help, but it currently doesn't support the 3.0 preview. https://github.com/jburman/W8lessLabs.Blazor.LocalFiles
(no affiliation with the developer)
The input control will give you the location of the file as a full path along with the name of the file. Then you still have to retrieve the file and download it to the server.
Late response but with 3.1 there is an additional AspNetCore.Components module you can download via NuGet to get access to HttpClient extensions. These make it simple:
// fetch mock data for now
var results = await _http.GetJsonAsync<WellDetail[]>("sample-data/well.json");
You could inject the location of the file from your input control in place of the "sample-data/well.json" string.
Something like:
using Microsoft.AspNetCore.Components;
private async Task<List<MyData>> LoadFile(string filePath)
{
HttpClient _http;
// fetch data
// convert file data to MyData object
var results = await _http.GetJsonAsync<MyData[]>(filePath);
return results.ToList();
}
I am uploading user profile image which is uploading and moved to storage/app/upload/images folder but when I am trying to display that image, below given error occurs.
Method App\Image::__toString() must not throw an exception, caught Illuminate\Database\Eloquent\JsonEncodingException
Here is my controller function for displaying
public function userProfile() {
$image = Image::all();
return view('frontend.layouts.Profile',compact('image'));
}
My view in which I am displaying image
#foreach($image as $images)
<img style="width:210px ; height: 230px " src="/storage/app/upload/images/{{$images->image}}" >
#endforeach
Please Upload your image in Public directory and then try to access that, it will work fine
There are three ways of making an image available to a user:
1. As a public asset
Here the image is made available to everyone. For instance your website logo, or landing page image would be accessed by all. So there is a url to the image that is easily accessed by all. These sort of files would go straight to public/img/ folder.
2. As a protected image available only if specific url is requested
Here user specific images would be accessed by specific people. Think of your members' personal photos that you want to make available only to the member herself or to some specific person. In this case you would store the images in storage/app/public and make a symlink using the artisan command php artisan storage:link You can read more on this here. Assuming that you store your files using random names using str_random() you would then generate urls to your image using the asset() helper like: echo asset('storage/X3jf5j5b2j3n.jpg'); Given that the file names are random, it would be hard to access this image by everyone excepting those who have the url generated using the asset() helper.
3. As a protected image made available using Intervention library
In this case you would first check if user is logged in and then dynamically load the image using Intervention via another protected route. So in your web routes you would first have the user authorization using auth middleware:
Route::group(['middleware' => 'auth'], function () {
Route::get('user', 'UserController#userProfile');
Route::get('images/{image}', 'UserController#serveImage'); // this route serves the image only if user is logged in
});
Then once your have installed Intervention library using composer, our UserController would look like:
use Intervention;
class UserController extends Controller
{
public function userProfile()
{
$images = Image::all();
return view('frontend.layouts.Profile', compact('images'));
}
public function serveImage($image)
{
$filename = storage_path('app/images/'.$image);
return Intervention::make($filename)->response();
}
}
You can see that the image is now being served from the storage folder and not public folder. So this method serveImage() is called only when the route defined earlier for it is authorized. Intervention then works its magic to read the image and send it as a http response.
Your view would change one tad bit to accommodate the new route end point that we defined called images. I assume here that you are storing the filename of the image in db by a field named filename:
#foreach($images as $image)
<img style="width:210px ; height: 230px " src="{{ url('/images/'.$image->filename) }}" >
#endforeach
Note: Do bear in mind that the preferred way to serve images is by using method 2 since it is much faster. You can use method 3 sparingly if you really don't want anyone to even stumble upon the files using the urls.
I am using the PDF.js library to display PDf files within my site (using the pdf_viewer.js to display documents on-screen), but the PDF files I am displaying are confidential and I need to be able to show them within the site but block non-authorized public folks from being able to view the same files just by typing in theie URLs and seeing them show up right in their browser.
I tried to add the Deny from all line in my htaccess file, but that also of courfse blocked the viewer from showing the docs, so that seems to be a no-go. Clearly anyone could simply look at inspector and see the pdf file that is being read by the viewer, so it seems a direct URL is not going to be secure in any way.
I did read about PDF.js being able to read binary data, but I have no knowledge of how I might read in a PDF in my own file system and prep it for use by the library, eveen if that means it is all a bit slower in loading to get the file contents and prep it on the fly.
Anyone have a solution that allows PDFJS to work without revealing the source PDF URL, or to otherwise read the file using local file calls?
Okay, after some testing, the solution is very easy:
Get the PDF data using an Ajax-called function that can figure out what actual file is to be viewed.
In that PHP file...
Read the file into memory, using fopen and fread normally.
Convert to base64 using the base64_encode
Pass that string back to the calling Javascript.
In the original calling function, use the following to convert the string to a Uint array and then pass that to the PDFJS library...
## The function that turns the base64 string into whatever a Uint8 array is...
function base64ToUint8Array(base64) {
var raw = atob(base64);
var uint8Array = new Uint8Array(raw.length);
for (var i = 0; i < raw.length; i++) {
uint8Array[i] = raw.charCodeAt(i);
}
return uint8Array;
}
## the guts that gets the file data, calls the above function to convert it, and then calls PDF.JS to display it
$.ajax({
type: "GET",
data: {file: <a file id or whatever distinguishes this PDF>},
url: 'getFilePDFdata.php', (the PHP file that reads the data and returns it encoded)
success: function(base64Data){
var pdfData = base64ToUint8Array(base64Data);
## Loading document.
PDFJS.getDocument(pdfData).then(function (pdfDocument) {
## Document loaded, specifying document for the viewer and
## the (optional) linkService.
pdfViewer.setDocument(pdfDocument);
pdfLinkService.setDocument(pdfDocument, null);
});
}
});
I am building a UI into a JAR for Spring Server. I have a bunch of Angular JS pages. I want to pass in a command line argument to my jar that tells it where the API server is like so:
java -jar application.jar --api=http://ip:9000
So my application.properties file has:
url=${api:http://localhost:9000}
The way I am currently doing is it just having a hardocoded js config file and on each of my .html pages:
<script src="../js/appName/config.angular.js"></script>
Which contains:
var configData = {
url:"http://localhost:9000"
};
And called in each file:
$scope.apiUrl = configData.url;
How do I tap into the applications.properties file that I can override with my JAR command line parameter during runtime vs. the way it has been coded now.
When you pass a value from command line and the same property name is present in properties file then spring boot overrides the value from command line. So to achieve what you want do something like this
In application.properties
#this is default value
app.url=localhost:8080
Create a class to map the properties value or you can use existing class or something else based on your project structure.
#Component
public class Sample {
#Value("${app.url}")
private String url;
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
}
Now when your execute a jar with argument --app.url="someserver:9090" the value will be overriden and you can use this value anywhere.
Note it will also work if you try to access the properties value directly in jsp using expression.
Try it, it works. I have used the same thing in my latest project which is a composite microservices and each component need each others url.
[Edit]
Reference : http://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-external-config.html
Am I getting it right: The client part is delivered by the application? So the part of the last sentence 'during runtime' has more the meaning of 'bootstrap/initial loading', right? One (old school) approach is to provide the entry html (e.g. index.html) through the application (a simple template engine) and provide the needed information with a setter in a JS config object:
// pseudo js code with thymeleaf
<script th:inline="javascript">
/*<![CDATA[*/
myConfig.url = [[${#httpServletRequest.remoteHost}]];
/*]]>*/
</script>
This is just a sample that will only set the remote host name but I think you get the idea.
Side note: I still don't really get why do you have to set this. If the application contains the client code, why do you work with absolute URLs for remote calls? (Disclaimer: I have only experience in Angular(2) and not with AngularJS)
I'm not sure how I should be serving partials from Symfony to Angular.
I was thinking I should set up a route in Symfony, and then have the controller output the file?
I wasn't sure however how to simply output a file from the controller (i.e. no twig stuff, not really rendering anything, etc.) And will this method cache it properly?
For example,if I want angular to download partials/button.html, should I set up a route like:
partials:
pattern: /web/partials/{partial}
defaults: { _controller: AcmeWebBundle:Partials:show, _format: html }
Then, in my controller have,
...
public function showAction() {
return file_get_contents(' ... path to file ...');
}
....
That obviously doesn't work.. I'm not sure how to output just a straight file without going through twig. Or maybe all my partials should just be twig files (just without any twig stuff in them)?
If you wanted to return the contents like that you would need to add the contents of the file to the response body.
use Symfony\Component\HttpFoundation\Response;
...
public function showAction() {
return new Response(file_get_contents(' ... path to file ...'),200);
}
...
But really you should just let your web server serve the file. What I do is put my partials in a sub folder under the web directory:
web/
partials/
img/
js/
css/
Then just call them domain.com/parials/partialFileName.html and because the file exists symfonys rewrites should ignore it by default and just serve the file.
Another method (mentioned here) is to put the files in your bundle's Resources/public folder, then run
php app/console assets:install --symlink
(where web is the actual directory web/)
This will generate symlinks in the web directory pointing to the public directories. So, if you have:
Acme/DemoBundle/Resources/public/partials/myPartial.html
it'll be available at:
http://www.mydomain.com/bundles/acmedemo/partials/myPartial.html