CodeCrafters
Build your own BitTorrent
Learn about .torrent files, the BitTorrent Peer Protocol and more
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Python
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Java
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Kotlin
Ruby
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Zig
C
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C#
Elixir
TypeScript
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BitTorrent is a peer-to-peer file sharing protocol used for distributing large amounts of data. In this challenge, you'll build a BitTorrent client that's capable of downloading a publicly available file using the BitTorrent protocol.
Along the way, you'll learn about the BitTorrent protocol, .torrent files more.
Stages
Decode bencoded strings
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Decode bencoded integers
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Decode bencoded lists
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Decode bencoded dictionaries
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Parse torrent file
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Calculate info hash
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Piece hashes
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Discover peers
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Peer handshake
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Download a piece
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Download the whole file
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Magnet Links
Parse magnet link
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Announce extension support
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Send extension handshake
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Receive extension handshake
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Request metadata
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Receive metadata
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Download a piece
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Download the whole file
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RECENT ATTEMPTS
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“
There are few sites I like as much that have a step by step guide. The real-time feedback is so good, it's creepy!
Ananthalakshmi Sankar
Automation Engineer at Apple
“
I think the instant feedback right there in the git push is really cool.
Didn't even know that was possible!
Patrick Burris
Senior Software Developer, CenturyLink
Ananthalakshmi Sankar
Automation Engineer at Apple
“
I think the instant feedback right there in the git push is really cool.
Didn't even know that was possible!
Patrick Burris
Senior Software Developer, CenturyLink