HTTP Response

[Christian Knoblauch]

Hello,

i have a question regarding HTTP request/response using ASP.NET.

PROBLEM:

My client-application is behind a firewall, so that the server must be
reached using HTTP. A started job on the server need a long time (ca. 1
hour) and produce intermediate results in a "not" fixed time-grid (that
means polling is not the best solution).

IDEA:

Some times ago i read an article to send a HTTP response in little pieces,
but i forget the location of that article ;-( My idea is to use this
approach for the server, every intermediate result send a little pice of the
HTTP response until the end of the job finish the HTTP response.

QUESTION:

I'am not sure if this is possible (especially over this long time of job).
In a book about HTTP i can't find such a solution in the first place. Is
this possible in ASP.NET ? I now that the HTTP implementation in ASP.NET is
very flexible/pluggable. Can one provide an example or link if this can be
done ?

Thanks in advantage !

Best Regards
Christian

 

[David Browne]

Hello,

i have a question regarding HTTP request/response using ASP.NET.

PROBLEM:

My client-application is behind a firewall, so that the server must be
reached using HTTP. A started job on the server need a long time (ca. 1
hour) and produce intermediate results in a "not" fixed time-grid (that
means polling is not the best solution).

IDEA:

Some times ago i read an article to send a HTTP response in little pieces,
but i forget the location of that article ;-( My idea is to use this
approach for the server, every intermediate result send a little pice of the
HTTP response until the end of the job finish the HTTP response.

This is possible, but requires it quite tricky to implement in ASP.NET
because it would require you to block an ASP.NET worker thread. A more
common approach to this problem is the "Orbitz" approach. The client
submits the job in one HTTP request and the server starts the job on an
application-created background thread (importantly not a thread-pool
thread), them immediately responds with a job ID to the client. The client
then waits and periodically sends additional HTTP requests quering the
status of the job.

David