I'm developing an integration between 2 applications. Application 1 uses HttpClient GetMethod to request from Application 2. Application 2 will return a multipart response with files embedded. I thought this was a simple exercise, but cannot seem to find common support for parsing a multipart response from HTTP GET. How can Application 1 parse the multipart response from Application 2?
As you are using multi part encode to send the request to the server(Servlet). As multi part encode encrypt all the data in that form you have to decrypt them first and then you can use those values.
Please follow this link.
What does enctype='multipart/form-data' mean?.
Convenient way to parse incoming multipart/form-data parameters in a Servlet.
I was also stuck with same problem. I solved it using javax mail MimeMultiPart. you can see my solution here:- https://stackoverflow.com/a/42548549/5236494
For posterity, there is nothing wrong with this pattern even if it is badly supported by HTTP libraries:
https://www.w3.org/Protocols/rfc1341/7_2_Multipart.html
Notice, though that Content-Type isn't multipart/form-data but multipart/mixed but encoding with boundaries between parts is nearly identical.
Related
How can I write a content of a file into http response? I prefer to write it to an entity first if possible. I searched for examples, but unfortunately didn't find any suitable working one..
Of course it is possible. After all that's what all web servers do when they serve you pages. Add proper Content-Type and Content-Lenght (if known) to your headers, open your file, read it and write it your response.
I want to read a multipart/mixed content-type response returned from xquery in java. I am using http client in java to call/execute the xquery. In java i can able to get only the response body as string or stream or byte content. I want to separate the parts of the multipart response in java using existing multipart APIs.
As far as I know, the Apache HTTP Client does not support such a multipart response. But you can use MIME4J for instance to parse it. The class org.expath.httpclient.impl.MultipartResponseBody does exactly that (look at the function analyzeParts).
On running the example provided in the link https://hc.apache.org/httpcomponents-client-ga/httpmime/examples/org/apache/http/examples/entity/mime/ClientMultipartFormPost.java, I am getting the below exception
com.sun.xml.ws.server.UnsupportedMediaException: Unsupported Content-Type: multipart/form-data; boundary=APQdLVD1_Zc9bPMSMCmGCk012pvQ6Yv Supported ones are: [text/xml]
Any idea why it is coming?
I think you are confusing two topics:
A HTML form post
A SOAP request post
In the former you indeed send a multipart/form-data as you seem to have done.
In the latter you generally don't send multiparts (unless you are using something like MTOM) but simply post the entire content as "application/soap+xml"
When using MTOM, you don't use multipart/form-data but multipart/related and you still need to follow some conventions that are not found in HTML and as such not in the example code you posted.
Does anyone have an example of how to send both binary (image) and text-based data in a single servlet response? An example is returning an image and image-map all generated on the server. I was also not able to find a mixed-mode mime type to use to be able to perform this operation.
Thoughts?
Browser support for multipart responses is still pretty dicey (read here). But if you are planning to parse the response on the client side yourself there are some pretty good examples out there. The mime-type you are looking for is multipart/mixed.
You can use Data URI to embed binary objects into generated HTML.
E.g.
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4/8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot">
See also: https://serverfault.com/questions/241218/why-do-http-servers-not-send-a-single-file-back-when-possible#241224
This is not how HTTP and HTML work. A first request is made to load HTML code. This HTML code contains <img src="..."/> tags, which point to the URL of the image. A second request is then made by the browser to load the image. You can't download the HTML and the image in a single request.
Many WAP browsers supports multi-part responses, but I don't think "regular" browsers do.
Also see Browser support of multipart responses
I'm a little unfamiliar both with the Servlet API and Apache Http Components.
I need to handle an incoming POST request with unknown data (although probably the result of a form submission) using HttpServlet.doPost() which I've implemented, and request the same posted information from another URL, effectively acting as a relay for the HTTP POST. I then need to convert the response to a String (it will be text/html) and process it further before returning it to the web browser that requested it from me.
Due to my unfamiliarity with these libraries, its not clear to me how to handle issues like the content-type of the posted data, and also avoiding any problems due to neglecting to release resources.
Can anyone provide any pointers on this?
You should start by having a look at HttpClient class from apache API.
It will handle both get and posts as needed and later you could feel its request with the data you receive in your own servlet.