File size of web-based flv. Reading some bytes from a web-based file

ruby-talk
1

This is such a noobie question.

I have a file, http:// ... /One-minute-commercial-027.flv (I can't enter the name because the email gets rejected with a 5.7.1 as spam, apparently.

I want to do two simple things:

1) I want to get the file size. Please note that File.size() does not seem to work for me for a web-based file but does work for a local file.

C:\Users\Ralph>irb
irb(main):001:0> File.size('c:/RailsInstaller/Sites/ultradedup002/app/views/usage/VideoTutorials.html.haml')
=> 32406
irb(main):002:0> File.size('http:// ... /One-minute-commercial-027.flv')
Errno::EINVAL: Invalid argument - http:// something /One-minute-commercial-027.flv
        from (irb):2:in `size'
        from (irb):2
        from C:/RailsInstaller/Ruby1.9.2/bin/irb:12:in `<main>'
irb(main):003:0>

2) I want to read a few hundred bytes from the beginning of the file so as to pick up the flv's time duration.

Are there Ruby facilities to do this?

Ralph Shnelvar

2

You should probably make a HEAD request and parse Content-Length header

curl --head '<Your URL>' | grep 'Content-Length'

http:// ... /One-minute-commercial-027.flv'

···

On 03/01/12 6:56 PM, Ralph Shnelvar wrote:

This is such a noobie question.

I have a file, http:// ... /One-minute-commercial-027.flv (I can't enter the name because the email gets rejected with a 5.7.1 as spam, apparently.

I want to do two simple things:

1) I want to get the file size. Please note that File.size() does not seem to work for me for a web-based file but does work for a local file.

C:\Users\Ralph>irb
irb(main):001:0> File.size('c:/RailsInstaller/Sites/ultradedup002/app/views/usage/VideoTutorials.html.haml')
=> 32406
irb(main):002:0> File.size('http:// ... /One-minute-commercial-027.flv')
Errno::EINVAL: Invalid argument - http:// something /One-minute-commercial-027.flv
         from (irb):2:in `size'
         from (irb):2
         from C:/RailsInstaller/Ruby1.9.2/bin/irb:12:in `<main>'
irb(main):003:0>

2) I want to read a few hundred bytes from the beginning of the file so as to pick up the flv's time duration.

Are there Ruby facilities to do this?

Ralph Shnelvar

3

Tuesday, January 3, 2012, 6:39:07 AM, you wrote:

You should probably make a HEAD request and parse Content-Length header

curl --head '<Your URL>' | grep 'Content-Length'

http:// ... /One-minute-commercial-027.flv'

Could you beef up the example/explanation a bit, please.

Also, what about reading a few hundred bytes from the flv?

···

On 03/01/12 6:56 PM, Ralph Shnelvar wrote:

This is such a noobie question.

I have a file, http:// ... /One-minute-commercial-027.flv (I can't enter the name because the email gets rejected with a 5.7.1 as spam, apparently.

I want to do two simple things:

1) I want to get the file size. Please note that File.size() does not seem to work for me for a web-based file but does work for a local file.

C:\Users\Ralph>irb
irb(main):001:0> File.size('c:/RailsInstaller/Sites/ultradedup002/app/views/usage/VideoTutorials.html.haml')
=> 32406
irb(main):002:0> File.size('http:// ... /One-minute-commercial-027.flv')
Errno::EINVAL: Invalid argument - http:// something /One-minute-commercial-027.flv
         from (irb):2:in `size'
         from (irb):2
         from C:/RailsInstaller/Ruby1.9.2/bin/irb:12:in `<main>'
irb(main):003:0>

2) I want to read a few hundred bytes from the beginning of the file so as to pick up the flv's time duration.

Are there Ruby facilities to do this?

Ralph Shnelvar

--
Best regards,
Ralph mailto:ralphs@dos32.com

4

using net/http -- something like

ruby-1.9.2-p290 :035 > uri = URI('http://localhost/&#39;\)
=> #<URI::HTTP:0x00000101861f80 URL:http://localhost/&gt;
ruby-1.9.2-p290 :036 > req = Net::HTTP::Get.new(uri.request_uri)
=> #<Net::HTTP::Get GET>
ruby-1.9.2-p290 :037 > req['Range'] = 'bytes=0-99'
=> "bytes=0-99"
ruby-1.9.2-p290 :038 > Net::HTTP.start(uri.host, uri.port) {|http|
http.request(req) }.body
=> "<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"\n
     "http://www.w3.org/TR/xhtml1/D&quot;
ruby-1.9.2-p290 :039 >

The above *does* assume that your web server supports the Range
header, so YMMV.

···

On Tue, Jan 3, 2012 at 6:03 AM, Ralph Shnelvar <ralphs@dos32.com> wrote:

Also, what about reading a few hundred bytes from the flv?

--
Hassan Schroeder ------------------------ hassan.schroeder@gmail.com

twitter: @hassan