writing down filecaps: revise URI scheme #432

New Issue

warner · 2008-06-01T21:34:06Z

warner commented

2008-06-01 21:34:06 +00:00

I'd like to sit down and draw up a plan for "cap reification": what are the exact strings used to represent our various file/directory capabilities. We know that there will be at least two kinds (human-readable and packed machine-readable), and that we might want the human-readable ones to be browser-friendly (or 72-column friendly, or concise, or some combination thereof). And we've drawn up a couple of proposals based upon adequate crypto key sizes and "base62" encoding schemes, but we haven't finished the roadmap yet.

Various features and tradeoffs:

printable
pronounceable, error-resistant (base32 with o/0 tolerance)
short
browser-friendly (starts with <http://localhost>)
IANA-friendly (starts with x-tahoe: or tahoe:)
email friendly (printable and shorter than 72 characters)
self-identifying (includes some redundant prefix, version number)
visually distinct

I'd like to sit down and draw up a plan for "cap reification": what are the exact strings used to represent our various file/directory capabilities. We know that there will be at least two kinds (human-readable and packed machine-readable), and that we might want the human-readable ones to be browser-friendly (or 72-column friendly, or concise, or some combination thereof). And we've drawn up a couple of proposals based upon adequate crypto key sizes and "base62" encoding schemes, but we haven't finished the roadmap yet. Various features and tradeoffs: * printable * pronounceable, error-resistant (base32 with o/0 tolerance) * short * browser-friendly (starts with `<http://localhost>`) * IANA-friendly (starts with `x-tahoe:` or `tahoe:`) * email friendly (printable and shorter than 72 characters) * self-identifying (includes some redundant prefix, version number) * visually distinct

warner added the

labels 2008-06-01 21:34:06 +00:00

warner added this to the 1.5.0 milestone 2008-06-01 21:34:06 +00:00

warner commented

2008-06-01 21:40:48 +00:00

Related tickets:

#418: create tahoe: URI scheme identifier, register with IANA
#217: DSA-based mutable files, will enable shorter caps
#102: "smaller and prettier directory URIs"
#105: "command-line access to URIs" (printable caps should be distinguishable
from filenames, so "tahoe cp $CAP local/foo.txt" is not too ambiguous)
#52: "browser integration": caps that are legal URIs and make IANA happy can also
be handled by browser plugins
#125: caps for files and directories should be human-distinguishable. It is even
more important that humans be able to distinguish read-caps and write-caps.

Related tickets: * #418: create `tahoe:` URI scheme identifier, register with IANA * #217: DSA-based mutable files, will enable shorter caps * #102: "smaller and prettier directory URIs" * #105: "command-line access to URIs" (printable caps should be distinguishable from filenames, so "tahoe cp $CAP local/foo.txt" is not too ambiguous) * #52: "browser integration": caps that are legal URIs and make IANA happy can also be handled by browser plugins * #125: caps for files and directories should be human-distinguishable. It is even more important that humans be able to distinguish read-caps and write-caps.