Partial Read From URL

[Elliot Temple]

Can anyone see a problem with this code to read only 20k from a URL? The
http connection will get closed, right?

Is there a better way to do this? My goal is to download the start of
mp3 files and then estimate their duration without downloading the
entire file.

def partial_uri_read(uri)
u = URI.parse(uri)
s = ""
Net::HTTP.start(u.host, u.port) do |http|
http.request_get(u.path) do |response|
response.read_body do |chunk|
s << chunk
return s if s.size > 20000
end
end
end
s
end

Thanks
Elliot Temple

 

[ara.t.howard]

Can anyone see a problem with this code to read only 20k from a URL?
The
http connection will get closed, right?

Is there a better way to do this? My goal is to download the start of
mp3 files and then estimate their duration without downloading the
entire file.

def partial_uri_read(uri)
u = URI.parse(uri)
s = ""
Net::HTTP.start(u.host, u.port) do |http|
http.request_get(u.path) do |response|
response.read_body do |chunk|
s << chunk
return s if s.size > 20000
end
end
end
s
end

Thanks
Elliot Temple

maybe try


require 'open-uri'

uri = ......

open(uri){|fd| fd.read 20000}




a @ http://codeforpeople.com/

 

[Elliot Temple]

maybe try


require 'open-uri'

uri = ......

open(uri){|fd| fd.read 20000}

I did try that, but it downloads the entire file in my tests. I tried it
on a large file and it takes minutes to return, whereas my code returns
in a couple seconds. Am I missing something?

ruby -v

ruby 1.8.6 (2008-03-03 patchlevel 114) [universal-darwin9.0]

Elliot

 

[Michael Morin]

Can anyone see a problem with this code to read only 20k from a URL? The
http connection will get closed, right?

Is there a better way to do this? My goal is to download the start of
mp3 files and then estimate their duration without downloading the
entire file.

def partial_uri_read(uri)
u = URI.parse(uri)
s = ""
Net::HTTP.start(u.host, u.port) do |http|
http.request_get(u.path) do |response|
response.read_body do |chunk|
s << chunk
return s if s.size > 20000
end
end
end
s
end

Thanks
Elliot Temple

You can try using the Range header in HTTP. Not all servers have it
enabled I think (or that's what 3 minutes playing with telnet tells me).
Using range you can define which bytes of the file you want to
download, so the whole file is not downloaded. You can use this to
download the header and use the length of the file to estimate its length.