Pinch - Some crazy HTTP ZIP Magic

Retrieve a file from inside a ZIP file, over the network!

Pretty sweet, eh?

Transcript

1. PINCH
   Some crazy
   HTTP ZIP Magic
   

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2. @peterhellberg
   

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3. I’m a Senior Systems
   Architect at Athega
   (where I build stuff in Ruby)
   ⃔
   I’m also the owner
   o Code7 Interactive
   (where I build stuff in Ruby)
   ⃕
   

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4. Retrieve a ile rom
   inside a ZIP ile,
   over the network!
   Pretty sweet, eh?
   

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5. require 'pinch'
   url = 'http://peterhellberg.github.com/pinch/test.zip'
   data = Pinch.get(url, 'data.json')
   # Do something with the data
   How?
   

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6. Now, let’s go
   back in⏰
   

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7. ’89
   APPNOTE.TXT
   http://PKWARE.com/documents/casestudies/APPNOTE.TXT
   

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8. FILE ENTRY 1
   FILE ENTRY 2
   CENTRAL DIRECTORY
   END OF CENTRAL DIRECTORY
   Signature 0x06054b50
   
   ZIP File Format
   

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9. Pinch does NOT
   understand the
   ZIP File Format
   

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10. HTTP/1.1
    14.16 Content-Range
    ❤ || ☠
    

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11. 1 HEAD Total ile size
    2 GET Last 4096 bytes (End of Central Directory)
    3 GET Central Directory start → Central Directory start + size
    4 GET File offset → File offset + (compressed) size
    HTTP Requests
    

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12. String#unpack
    Zlib::In late
    Array#pack
    

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13. gem install pinch
    

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14. github.com/peterhellberg/pinch
    

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15. @peterhellberg
    peterhellberg.info
    git.io/peterhellberg
    

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