Question
Parsing multipart/form-data response from Connect-REST
What are the options for processing a multipart/form-data response from a REST service? We are receiving a response with an attachment, what would be the best way to extract that file as well as the json response data accompanying it? Does anyone have experience with this or know of resources they can point me to? Searches within PDN have not returned much information on processing multipart responses.
~ Thank you.
Hi,
Analysis of the Connect-REST multipart functionality (attachments )
In general we have four properties to be set on pyRequestAttachmentPage(Data-ServiceMessage)
The generation of multipart request depends on the four properties which is present in Data-ServiceMessage class
1)pyAttachFileNames
2)pyAttachTypes
3)pyAttachValues
4)pyAttachNames
UseCase-1 (Setting all the properties)-Generates the following message
POST / HTTP/1.1
Content-Length: 220
Content-Type: multipart/form-data; boundary=QHdb-kDg6LLU0cJOgInu1ExR_GY95o
Host: google.com:8877
Connection: Keep-Alive
User-Agent: Apache-HttpClient/UNAVAILABLE (java 1.5)
--QHdb-kDg6LLU0cJOgInu1ExR_GY95o
Content-Disposition: form-data; name="attachname"; filename="santy.txt"
Content-Type: application/json
Content-Transfer-Encoding: binary
?©ž±©í
--QHdb-kDg6LLU0cJOgInu1ExR_GY95o--
Here is the summary of each type
Value of pyAttachTypes is content type –see highlighted in blue
Value of pyAttachNames and pyAttachFileNames is a part of content disposition header-see highlighted text in yellow
Over all content type of the message is multipart/form-data-highlighted in red
Usecase-2 Not setting pyAttachTypes - content type of individual part is defaulted to application/octetstream
POST / HTTP/1.1
Content-Length: 248
Content-Type: multipart/form-data; boundary=Qj8f74fBMDunqoRSdJqh38KRUxJIzXMN6hLe2njS
Host: google.com:8877
Connection: Keep-Alive
User-Agent: Apache-HttpClient/UNAVAILABLE (java 1.5)
--Qj8f74fBMDunqoRSdJqh38KRUxJIzXMN6hLe2njS
Content-Disposition: form-data; name="attachname"; filename="santy.txt"
Content-Type: application/octet-stream
Content-Transfer-Encoding: binary
?©ž±©í
--Qj8f74fBMDunqoRSdJqh38KRUxJIzXMN6hLe2njS--
Usecase-3Not setting pyAttachFileNames
pyAttachFileNames is defaulted to pyAttachnames
POST / HTTP/1.1
Content-Length: 229
Content-Type: multipart/form-data; boundary=b4S38RrAPScj8swlzOyPRB79OzD0f6Uxhy
Host: google.com:8877
Connection: Keep-Alive
User-Agent: Apache-HttpClient/UNAVAILABLE (java 1.5)
--b4S38RrAPScj8swlzOyPRB79OzD0f6Uxhy
Content-Disposition: form-data; name="attachname"; filename="attachname"
Content-Type: application/json
Content-Transfer-Encoding: binary
?©ž±©í
--b4S38RrAPScj8swlzOyPRB79OzD0f6Uxhy--
Not setting pyAttachname and pyAttachFileNames - No data is sent as binary attachment, at least attachname is mandatory
POST / HTTP/1.1
Content-Length: 37
Content-Type: multipart/form-data; boundary=q75QKTzvoo0A_ZoTMqSZhaDh3AVQgua
Host: google.com:8877
Connection: Keep-Alive
User-Agent: Apache-HttpClient/UNAVAILABLE (java 1.5)
--q75QKTzvoo0A_ZoTMqSZhaDh3AVQgua--
Conclusion: pyAttachname,pyValues is mandatory to be set, pyAttachtype and pyAttachFilename is also optional
pyAttachtype generates content-type of the part
if not given falls back to default application/octetstream
pyAttachname generates the content-disposition header where name is the parameter
if pyAttachname option is not given the file name is defaulted to whatever value is specified in attachname
Hope this can help you.
Thanks,
Narasimha
You can handle the attachments in response using 'pyResponseAttachmentPage' which will have pyAttachValues pagelist to handle each attachment returned by the service.