From: Daira Hopwood Date: Tue, 7 Oct 2014 20:04:40 +0000 (+0100) Subject: Improve comments in _auto_deps.py. refs #2249, #2028, #2193, #2005, #1258 X-Git-Tag: allmydata-tahoe-1.10.1a1~116 X-Git-Url: https://git.rkrishnan.org/Site/Content/Exhibitors/FOOURL?a=commitdiff_plain;h=refs%2Fpull%2F118%2Fhead;p=tahoe-lafs%2Ftahoe-lafs.git Improve comments in _auto_deps.py. refs #2249, #2028, #2193, #2005, #1258 Signed-off-by: Daira Hopwood --- diff --git a/src/allmydata/_auto_deps.py b/src/allmydata/_auto_deps.py index b05309c1..4993c563 100644 --- a/src/allmydata/_auto_deps.py +++ b/src/allmydata/_auto_deps.py @@ -22,18 +22,7 @@ install_requires = [ # transferring large mutable files of size N. # * foolscap < 0.6 is incompatible with Twisted 10.2.0. # * foolscap 0.6.1 quiets a DeprecationWarning. - # * foolscap < 0.6.3 is incompatible with Twisted-11.1.0 and newer. Since - # current Twisted is 12.0, any build which needs twisted will grab a - # version that requires foolscap>=0.6.3 - # * pyOpenSSL is required by foolscap for it (foolscap) to provide secure - # connections. Foolscap doesn't reliably declare this dependency in a - # machine-readable way, so we need to declare a dependency on pyOpenSSL - # ourselves. Tahoe-LAFS doesn't *really* depend directly on pyOpenSSL, - # so if something changes in the relationship between foolscap and - # pyOpenSSL, such as foolscap requiring a specific version of - # pyOpenSSL, or foolscap switching from pyOpenSSL to a different crypto - # library, we need to update this declaration here. - # + # * foolscap < 0.6.3 is incompatible with Twisted 11.1.0 and newer. "foolscap >= 0.6.3", # Needed for SFTP. @@ -95,6 +84,11 @@ import sys if not hasattr(sys, 'frozen'): package_imports.append(('setuptools', 'setuptools')) + +# Splitting the dependencies for Windows and non-Windows helps to fix +# and +# . + if sys.platform == "win32": install_requires += [ # * On Windows we need at least Twisted 9.0 to avoid an indirect @@ -149,10 +143,32 @@ else: ('pyasn1-modules', 'pyasn1_modules'), ] -# If pyOpenSSL >= 0.14 is *already* installed, then accept it, otherwise -# require pyOpenSSL 0.13 or 0.13.1. -# See for why -# we don't rely on pkg_resources to tell us the installed pyOpenSSL version number. + +# * pyOpenSSL is required in order for foolscap to provide secure connections. +# Since foolscap doesn't reliably declare this dependency in a machine-readable +# way, we need to declare a dependency on pyOpenSSL ourselves. Tahoe-LAFS does +# not *directly* depend on pyOpenSSL. +# +# * pyOpenSSL >= 0.13 is needed in order to avoid +# . +# +# * pyOpenSSL >= 0.14 is built on the 'cryptography' package which depends +# on 'cffi' (and indirectly several other packages). Unfortunately cffi +# attempts to compile code dynamically, which causes problems on many systems. +# It also depends on the libffi OS package which may not be installed. +# +# +# +# So, if pyOpenSSL 0.14 has *already* been installed and is importable, we +# want to accept it; otherwise we ask for pyOpenSSL 0.13 or 0.13.1. +# +# +# We don't rely on pkg_resources to tell us the installed pyOpenSSL version +# number, because pkg_resources telling us that we have 0.14 is not sufficient +# evidence that 0.14 will be the imported version (or will work correctly). +# One possible reason why it might not be is explained in +# and +# . _can_use_pyOpenSSL_0_14 = False try: @@ -165,8 +181,8 @@ except Exception: if _can_use_pyOpenSSL_0_14: install_requires += [ - # pyOpenSSL >= 0.13 is needed in order to fix - # . + # Although we checked for pyOpenSSL >= 0.14 above, we only actually + # need pyOpenSSL >= 0.13; requiring 0.14 here cannot help. "pyOpenSSL >= 0.13", # ... and now all the new stuff that pyOpenSSL 0.14 transitively