In a web project using jsp, I have following requirement
Upload a file (say an image) to a different domain, which returns an xml that includes details of uploaded file (eg: path of uploaded image etc).
How do I capture this xml to save details in db?
I cannot do a normal html form submit, since I lose control after that. So I tried to implement this by setting form target to an iframe. But I cannot process contents of iframe?
Any suggestions how I can accomplish this?
Can I process this using yql?
Yes, you can do this using YQL. Not easy though, and you'll need to set up your own YQL table.
Each YQL table is a XML file describing how to operate on data. The YQL XML specification allows you to define an <execute> element that you can use to write JavaScript code that does almost anything.
Inside this <execute> block, you can use the y.rest object to POST data somewhere else.
You'll probably have to encode the file using base64 to be able to actually POST data using the YQL syntax, something like INSERT INTO mywebsite.files (name, data) VALUES ('foo.png', 'KBB987987JJBHBGV==') (second param is a illustrative base64-encoded file).
Assuming the server you are submitting the file to is not under your control (so you can't use CORS), you have proxy the request through your own server.
You can't use YQL as you can't make post requests with it.
Related
I am developing a web app which functions in a similar way to a search engine (except it's very specific and on a much smaller scale). When the user gives a query, I parse that query, and depending on what it is, proceed to carry out one of the following:
Grab data from an XML file located on another domain (ie: from www.example.com/rss/) which is essentially an RSS feed
Grab the HTML from an external web page, and proceed to parse it to locate text found in a certain div on that page
All the data is plain text, save for a couple of specific queries which will return images. This data will be displayed without requiring a page refresh/redirect.
I understand that there is the same domain policy which prevents me from using Javascript/Ajax to grab this data. An option is to use PHP to do this, but my main concern is the server load.
So my concerns are:
Are there any workarounds to obtain this data client-side instead of server-side?
If there are none, is the optimum solution in my case to: obtain the data via my server, pass it on to the client for parsing (with Javascript/Ajax) and then proceed to display it in the appropriate form?
If the above is my solution, all my server is doing with PHP is obtaining the data from the external domains. In the worst (best?) case scenario, let's say a thousand or so requests are being executed in a minute, is it efficient for my web server to be handling all those requests?
Once I have a clear idea of the flow of events it's much easier to begin.
Thanks.
I just finish a project to do the same request like your req.
My suggestion is:
use to files, [1] for frontend, make ajax call to sen back url; [2] receive ajax call, and get file content from url, then parse xml/html
in that way, it can avoid your php dead in some situation
for php, please look into [DomDocument] class, for parse xml/html, you also need [DOMXPath]
Please read: http://www.php.net/manual/en/class.domdocument.php
No matter what you do, I suggest you always archive the data in you local server.
So, the process become - search your local first, if not exist, then grab from remote also archive for - 24 hrs.
BTW, for your client-side parse idea, I suggest you do so. jQuery can handle both html and xml, for HTML you just need to filter all the js code before parse it.
So the idea become :
ajax call local service
local php grab xm/html (but no parsing)
archive to local
send filter html/xml to frontend, let jQuery to parse it.
HTML is similar to XML. I would suggest grabbing the page as HTML and traversing through it with an XML reader as XML.
I need to pass a bunch of parameters to a web API method which returns a byte array that is needed to display a PDF report on a page. I tried doing this via a GET method but the query string is too long and it throws an exception. I have tried shortening the query string as much as physically possibly but it is still too long. All of the external PDF viewer libraries require a string path to the PDF. I need something that allows me to supply a string path and some parameters or just a string path but that uses a POST instead of a GET. I was thinking about POSTing the object values to the web API along with a GUID and storing it somehow on the server then with an tag calling another API method and retrieving the stored data by only passing the GUID as a parameter but I don't want to make a database table for only that to save and retrieve the data. I entertained the idea of saving the byte array to a PDF on the server and then simply pointing a PDF viewer to that after but I had no success with that either and that is not ideal.
File.WriteAllBytes(path, res);
The code above is the most common way I have found to save the file but when I open the new PDF file after it says it is corrupt and it won't allow me to open it. Ideally I would just find a method that allows me to POST data to my web API then embeds the result in a pdf.js/pdfObject/ control. Please help, this has stumped me for days. Thanks in advance!!
Lets say there is a url out there e.g. www.website.com/data.jsp
the link has the following JSON data
{"successful":"true","rows":[{"zip":"65472","user_id":"10843","name":"Rufio"}]}
I just want to be able to extract this data at runtime however I am having a hard time getting it using getJSON
$.getJSON("test2.jsp",function(result){
$("div").append(result.rows[0].user_id + " ");
});
Now if I run it using a local file with the data residing in test2.jsp as shown above it appends the user_id. However when I try to access "www.website.com/data.jsp" instead nothing happens. I don't believe the website is configured to work with JSONP either.
I need a way to figure out how to pull this data from the website at run time. Does anyone have any solutions or workarounds?
p.s. Is this something that might need to be sorted out on the other end? The people who own the website set this scenario up to be like a fake api call like typically you would pass in parameters to get back the specific information that you would need. In the case of this endpoint or url it just returns a single record or the file just contains the data listed above. They would like me to extract the data from their url at runtime.
You can't make a normal ajax call to to this other domain due to same origin policy.
You can use JSONP to load the remote page, but looking at that example output you wouldn't be able to access the data unless the remote site is setup for JSONP (assigning the JSON to a variable, calling a callback function, etc).
You could create a server-side passthrough script of your own. You don't mention what server-side technology you have available, but if you can use PHP, you do a passthrough like this:
<?php
echo file_get_contents("http://www.website.com/data.jsp");
?>
PHP (or any other server-side language) can fetch the remote data, and now you can use ajax to call your own script (which works since you're on the same domain).
I have a WEBUI (using html and DOJO) which talks to a Web Service. The data required in the WEBUI is coming from a java Web Service using REST Calls.
IE (HTML/DOJO) <------ REST CALL(xml response) ----> Java WS on tomcat.
I have a certain data for a call
<AllData>
<DataList>
<type>A</type>
<xcoord>20</xcoord>
<ycoord>20</ycoord>
<length>250</length>
<width>350</width>
<imageName>images/myPic.jpg</imageName>
</DataList>
</AllData>
But in this case, if I have a list of data, for rendering each image, I have to do a http call again to my server.
Instead, I came to know that I can embed the image itself in the REST XML response.
I know I can read the image through ImageIO/BufferedImage classes in Java. But if I use the same to send the data which is read, is it possible to render the image on Dojo?
If there is any other method where I can send the image in the REST Response (XML or JSON) and using Dojo render the same, please let me know.
One thing that I could think of is Data URL. It allows you to store the entire image in URL form. On the client, you can insert an <img> tag with src="data:image/gif;base64,R0lGOD...... and you're done.
The drawback of this is, that the encoding overhead is huge, you'll save a request, but the data to transfer is bigger. I only used this approach in CSS files for tiny icons, where it's reasonable.
But I'd think about it again. Is that one more request really that bad? If not, you can run the same approach as above, just with a normal URL (in case your images are accessible from the web).
Is it possible to get temporary filename with javascript?
I want upload a file using ajax... So, i want to get the tmp filename with js. Is this possible?
AJAX itself won't let you upload a file via a web form - you need to perform a traditional form post to a window (or a frame/iframe) in order to send binary content. Such a post must be handled by your server code (in Java, PHP, python, etc), which can process the stream into a temporary file (some languages/frameworks such as PHP can do this automatically).
You can then make the temporary file available via a URL scheme, and return this URL back as the result page of the post. If this is all on the same domain as your main page, you can then use Javascript to look "inside" the result iframe to find the temporary URL.
If your using AJAX in combination with your server side language just return the temporary name and pull it in with the AJAX, if can all be done in 1 call.