view tests/test-hybridencode.py @ 26623:5a95fe44121d

clonebundles: support for seeding clones from pre-generated bundles

Cloning can be an expensive operation for servers because the server
generates a bundle from existing repository data at request time. For
a large repository like mozilla-central, this consumes 4+ minutes
of CPU time on the server. It also results in significant network
utilization. Multiplied by hundreds or even thousands of clients and
the ensuing load can result in difficulties scaling the Mercurial server.

Despite generation of bundles being deterministic until the next
changeset is added, the generation of bundles to service a clone request
is not cached. Each clone thus performs redundant work. This is
wasteful.

This patch introduces the "clonebundles" extension and related
client-side functionality to help alleviate this deficiency. The
client-side feature is behind an experimental flag and is not enabled by
default.

It works as follows:

1) Server operator generates a bundle and makes it available on a
   server (likely HTTP).
2) Server operator defines the URL of a bundle file in a
   .hg/clonebundles.manifest file.
3) Client `hg clone`ing sees the server is advertising bundle URLs.
4) Client fetches and applies the advertised bundle.
5) Client performs equivalent of `hg pull` to fetch changes made since
   the bundle was created.

Essentially, the server performs the expensive work of generating a
bundle once and all subsequent clones fetch a static file from
somewhere. Scaling static file serving is a much more manageable
problem than scaling a Python application like Mercurial. Assuming your
repository grows less than 1% per day, the end result is 99+% of CPU
and network load from clones is eliminated, allowing Mercurial servers
to scale more easily. Serving static files also means data can be
transferred to clients as fast as they can consume it, rather than as
fast as servers can generate it. This makes clones faster.

Mozilla has implemented similar functionality of this patch on
hg.mozilla.org using a custom extension. We are hosting bundle files in
Amazon S3 and CloudFront (a CDN) and have successfully offloaded
>1 TB/day in data transfer from hg.mozilla.org, freeing up significant
bandwidth and CPU resources. The positive impact has been stellar and
I believe it has proved its value to be included in Mercurial core. I
feel it is important for the client-side support to be enabled in core
by default because it means that clients will get faster, more reliable
clones and will enable server operators to reduce load without
requiring any client-side configuration changes (assuming clients are
up to date, of course).

The scope of this feature is narrowly and specifically tailored to
cloning, despite "serve pulls from pre-generated bundles" being a valid
and useful feature. I would eventually like for Mercurial servers to
support transferring *all* repository data via statically hosted files.
You could imagine a server that siphons all pushed data to bundle files
and instructs clients to apply a stream of bundles to reconstruct all
repository data. This feature, while useful and powerful, is
significantly more work to implement because it requires the server
component have awareness of discovery and a mapping of which changesets
are in which files. Full, clone bundles, by contrast, are much simpler.

The wire protocol command is named "clonebundles" instead of something
more generic like "staticbundles" to leave the door open for a new, more
powerful and more generic server-side component with minimal backwards
compatibility implications. The name "bundleclone" is used by Mozilla's
extension and would cause problems since there are subtle differences
in Mozilla's extension.

Mozilla's experience with this idea has taught us that some form of
"content negotiation" is required. Not all clients will support all
bundle formats or even URLs (advanced TLS requirements, etc). To ensure
the highest uptake possible, a server needs to advertise multiple
versions of bundles and clients need to be able to choose the most
appropriate from that list one. The "attributes" in each
server-advertised entry facilitate this filtering and sorting. Their
use will become apparent in subsequent patches.

Initial inspiration and credit for the idea of cloning from static files
belongs to Augie Fackler and his "lookaside clone" extension proof of
concept.

from mercurial import store

def show(s):
    # show test input
    print "A = '%s'" % s.encode("string_escape")

    # show the result of the C implementation, if available
    h = store._pathencode(s)
    print "B = '%s'" % h.encode("string_escape")

    # compare it with reference implementation in Python
    r = store._hybridencode(s, True)
    if h != r:
        print "R = '%s'" % r.encode("string_escape")
    print

show("data/abcdefghijklmnopqrstuvwxyz0123456789 !#%&'()+,-.;=[]^`{}")

print "uppercase char X is encoded as _x"
show("data/ABCDEFGHIJKLMNOPQRSTUVWXYZ")

print "underbar is doubled"
show("data/_")

print "tilde is character-encoded"
show("data/~")

print "characters in ASCII code range 1..31"
show('data/\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f'
          '\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f')

print "characters in ASCII code range 126..255"
show('data/\x7e\x7f'
          '\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f'
          '\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f')
show('data/\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf'
          '\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf')
show('data/\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf'
          '\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf')
show('data/\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef'
          '\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff')

print "Windows reserved characters"
show('data/less <, greater >, colon :, double-quote ", backslash \\'
           ', pipe |, question-mark ?, asterisk *')

print "encoding directories ending in .hg, .i or .d with '.hg' suffix"
show('data/x.h.i/x.hg/x.i/x.d/foo')
show('data/a.hg/a.i/a.d/foo')
show('data/au.hg/au.i/au.d/foo')
show('data/aux.hg/aux.i/aux.d/foo')
show('data/auxy.hg/auxy.i/auxy.d/foo')

print "but these are not encoded on *filenames*"
show('data/foo/x.hg')
show('data/foo/x.i')
show('data/foo/x.d')
show('data/foo/a.hg')
show('data/foo/a.i')
show('data/foo/a.d')
show('data/foo/au.hg')
show('data/foo/au.i')
show('data/foo/au.d')
show('data/foo/aux.hg')
show('data/foo/aux.i')
show('data/foo/aux.d')
show('data/foo/auxy.hg')
show('data/foo/auxy.i')
show('data/foo/auxy.d')

print "plain .hg, .i and .d directories have the leading dot encoded"
show('data/.hg/.i/.d/foo')

show('data/aux.bla/bla.aux/prn/PRN/lpt/com3/nul/coma/foo.NUL/normal.c.i')

show('data/AUX/SECOND/X.PRN/FOURTH/FI:FTH/SIXTH/SEVENTH/EIGHTH/NINETH/'
     'TENTH/ELEVENTH/LOREMIPSUM.TXT.i')
show('data/enterprise/openesbaddons/contrib-imola/corba-bc/netbeansplugin/'
     'wsdlExtension/src/main/java/META-INF/services/org.netbeans.modules'
     '.xml.wsdl.bindingsupport.spi.ExtensibilityElementTemplateProvider.i')
show('data/AUX.THE-QUICK-BROWN-FOX-JU:MPS-OVER-THE-LAZY-DOG-THE-QUICK-'
     'BROWN-FOX-JUMPS-OVER-THE-LAZY-DOG.TXT.i')
show('data/Project Planning/Resources/AnotherLongDirectoryName/'
     'Followedbyanother/AndAnother/AndThenAnExtremelyLongFileName.txt')
show('data/Project.Planning/Resources/AnotherLongDirectoryName/'
     'Followedbyanother/AndAnother/AndThenAnExtremelyLongFileName.txt')
show('data/foo.../foo   / /a./_. /__/.x../    bla/.FOO/something.i')

show('data/c/co/com/com0/com1/com2/com3/com4/com5/com6/com7/com8/com9')
show('data/C/CO/COM/COM0/COM1/COM2/COM3/COM4/COM5/COM6/COM7/COM8/COM9')
show('data/c.x/co.x/com.x/com0.x/com1.x/com2.x/com3.x/com4.x/com5.x'
                                        '/com6.x/com7.x/com8.x/com9.x')
show('data/x.c/x.co/x.com0/x.com1/x.com2/x.com3/x.com4/x.com5'
                                        '/x.com6/x.com7/x.com8/x.com9')
show('data/cx/cox/comx/com0x/com1x/com2x/com3x/com4x/com5x'
                                            '/com6x/com7x/com8x/com9x')
show('data/xc/xco/xcom0/xcom1/xcom2/xcom3/xcom4/xcom5'
                                            '/xcom6/xcom7/xcom8/xcom9')

show('data/l/lp/lpt/lpt0/lpt1/lpt2/lpt3/lpt4/lpt5/lpt6/lpt7/lpt8/lpt9')
show('data/L/LP/LPT/LPT0/LPT1/LPT2/LPT3/LPT4/LPT5/LPT6/LPT7/LPT8/LPT9')
show('data/l.x/lp.x/lpt.x/lpt0.x/lpt1.x/lpt2.x/lpt3.x/lpt4.x/lpt5.x'
                                        '/lpt6.x/lpt7.x/lpt8.x/lpt9.x')
show('data/x.l/x.lp/x.lpt/x.lpt0/x.lpt1/x.lpt2/x.lpt3/x.lpt4/x.lpt5'
                                        '/x.lpt6/x.lpt7/x.lpt8/x.lpt9')
show('data/lx/lpx/lptx/lpt0x/lpt1x/lpt2x/lpt3x/lpt4x/lpt5x'
                                            '/lpt6x/lpt7x/lpt8x/lpt9x')
show('data/xl/xlp/xlpt/xlpt0/xlpt1/xlpt2/xlpt3/xlpt4/xlpt5'
                                            '/xlpt6/xlpt7/xlpt8/xlpt9')

show('data/con/p/pr/prn/a/au/aux/n/nu/nul')
show('data/CON/P/PR/PRN/A/AU/AUX/N/NU/NUL')
show('data/con.x/p.x/pr.x/prn.x/a.x/au.x/aux.x/n.x/nu.x/nul.x')
show('data/x.con/x.p/x.pr/x.prn/x.a/x.au/x.aux/x.n/x.nu/x.nul')
show('data/conx/px/prx/prnx/ax/aux/auxx/nx/nux/nulx')
show('data/xcon/xp/xpr/xprn/xa/xau/xaux/xn/xnu/xnul')

show('data/a./au./aux./auxy./aux.')
show('data/c./co./con./cony./con.')
show('data/p./pr./prn./prny./prn.')
show('data/n./nu./nul./nuly./nul.')
show('data/l./lp./lpt./lpt1./lpt1y./lpt1.')
show('data/lpt9./lpt9y./lpt9.')
show('data/com./com1./com1y./com1.')
show('data/com9./com9y./com9.')

show('data/a /au /aux /auxy /aux ')

print "largest unhashed path"
show('data/123456789-123456789-123456789-123456789-123456789-'
          'unhashed--xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "shortest hashed path"
show('data/123456789-123456789-123456789-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "changing one char in part that's hashed away produces a different hash"
show('data/123456789-123456789-123456789-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxy-'
          '123456789-123456')

print "uppercase hitting length limit due to encoding"
show('data/A23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/Z23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "compare with lowercase not hitting limit"
show('data/a23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/z23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "not hitting limit with any of these"
show("data/abcdefghijklmnopqrstuvwxyz0123456789 !#%&'()+,-.;="
          "[]^`{}xxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-"
          "123456789-12345")

print "underbar hitting length limit due to encoding"
show('data/_23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "tilde hitting length limit due to encoding"
show('data/~23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "Windows reserved characters hitting length limit"
show('data/<23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/>23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/:23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/"23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/\\23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/|23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/?23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/*23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "initial space hitting length limit"
show('data/ 23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "initial dot hitting length limit"
show('data/.23456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "trailing space in filename hitting length limit"
show('data/123456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-1234 ')

print "trailing dot in filename hitting length limit"
show('data/123456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-1234.')

print "initial space in directory hitting length limit"
show('data/ x/456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "initial dot in directory hitting length limit"
show('data/.x/456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "trailing space in directory hitting length limit"
show('data/x /456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "trailing dot in directory hitting length limit"
show('data/x./456789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "with directories that need direncoding, hitting length limit"
show('data/x.i/56789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/x.d/56789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/x.hg/5789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "Windows reserved filenames, hitting length limit"
show('data/con/56789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/prn/56789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/aux/56789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/nul/56789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/com1/6789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/com9/6789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/lpt1/6789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')
show('data/lpt9/6789-123456789-123456789-123456789-123456789-'
          'xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "non-reserved names, just not hitting limit"
show('data/123456789-123456789-123456789-123456789-123456789-'
          '/com/com0/lpt/lpt0/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12345')

print "hashed path with largest untruncated 1st dir"
show('data/12345678/-123456789-123456789-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated 1st dir"
show('data/123456789/123456789-123456789-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated two dirs"
show('data/12345678/12345678/9-123456789-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated two dirs"
show('data/123456789/123456789/123456789-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated three dirs"
show('data/12345678/12345678/12345678/89-123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated three dirs"
show('data/123456789/123456789/123456789/123456789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated four dirs"
show('data/12345678/12345678/12345678/12345678/789-123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated four dirs"
show('data/123456789/123456789/123456789/123456789/123456789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated five dirs"
show('data/12345678/12345678/12345678/12345678/12345678/6789-'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated five dirs"
show('data/123456789/123456789/123456789/123456789/123456789/'
          'hashed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated six dirs"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/ed----xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated six dirs"
show('data/123456789/123456789/123456789/123456789/123456789/'
          '123456789/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated seven dirs"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/xxxxxx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated seven dirs"
show('data/123456789/123456789/123456789/123456789/123456789/'
          '123456789/123456789/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest untruncated eight dirs"
print "(directory 8 is dropped because it hits _maxshortdirslen)"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345678/xxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with smallest truncated eight dirs"
print "(directory 8 is dropped because it hits _maxshortdirslen)"
show('data/123456789/123456789/123456789/123456789/123456789/'
          '123456789/123456789/123456789/xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with largest non-dropped directory 8"
print "(just not hitting the _maxshortdirslen boundary)"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "...adding one truncated char to dir 1..7 won't drop dir 8"
show('data/12345678x/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678x/12345678/12345678/12345678/12345'
          '678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678x/12345678/12345678/12345'
          '678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678/12345678x/12345678/12345'
          '678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678/12345678/12345678x/12345'
          '678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678x/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678x/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path with shortest dropped directory 8"
print "(just hitting the _maxshortdirslen boundary)"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/123456/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "hashed path that drops dir 8 due to dot or space at end is"
print "encoded, and thus causing to hit _maxshortdirslen"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/1234./-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/1234 /-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print "... with dir 8 short enough for encoding"
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12./xx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12 /xx-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-123456')

print '''Extensions are replicated on hashed paths. Note that
we only get to encode files that end in .i or .d inside the
store. Encoded filenames are thus bound in length.'''
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.345.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.345.d')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.34567.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.345678.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-1.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-12.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-123.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-1234.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-12345.i')
show('data/12345678/12345678/12345678/12345678/12345678/12345'
          '678/12345678/12345/-xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-'
          '123456789-12.3456789-12345-ABCDEFGHIJKLMNOPRSTUVWX'
          'YZ-abcdefghjiklmnopqrstuvwxyz-ABCDEFGHIJKLMNOPRSTU'
          'VWXYZ-1234567890-xxxxxxxxx-xxxxxxxxx-xxxxxxxx-xxxx'
          'xxxxx-wwwwwwwww-wwwwwwwww-wwwwwwwww-wwwwwwwww-wwww'
          'wwwww-wwwwwwwww-wwwwwwwww-wwwwwwwww-wwwwwwwww.i')

print "paths outside data/ can be encoded"
show('metadata/dir/00manifest.i')
show('metadata/12345678/12345678/12345678/12345678/12345678/'
          '12345678/12345678/12345678/12345678/12345678/12345678/'
          '12345678/12345678/00manifest.i')