34 lines
1.1 KiB
Go
34 lines
1.1 KiB
Go
package flatfs
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var README_IPFS_DEF_SHARD = `This is a repository of IPLD objects. Each IPLD object is in a single file,
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named <base32 encoding of cid>.data. Where <base32 encoding of cid> is the
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"base32" encoding of the CID (as specified in
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https://github.com/multiformats/multibase) without the 'B' prefix.
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All the object files are placed in a tree of directories, based on a
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function of the CID. This is a form of sharding similar to
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the objects directory in git repositories. Previously, we used
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prefixes, we now use the next-to-last two charters.
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func NextToLast(base32cid string) {
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nextToLastLen := 2
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offset := len(base32cid) - nextToLastLen - 1
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return str[offset : offset+nextToLastLen]
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}
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For example, an object with a base58 CIDv1 of
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zb2rhYSxw4ZjuzgCnWSt19Q94ERaeFhu9uSqRgjSdx9bsgM6f
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has a base32 CIDv1 of
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BAFKREIA22FLID5AJ2KU7URG47MDLROZIH6YF2KALU2PWEFPVI37YLKRSCA
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and will be placed at
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SC/AFKREIA22FLID5AJ2KU7URG47MDLROZIH6YF2KALU2PWEFPVI37YLKRSCA.data
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with 'SC' being the last-to-next two characters and the 'B' at the
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beginning of the CIDv1 string is the multibase prefix that is not
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stored in the filename.
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`
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