[MacPorts] #63492: py37-openslide @1.1.2_1: OSError: dlopen(libopenslide.0.dylib, 6): image not found

[MacPorts]

#63492: py37-openslide @1.1.2_1: OSError: dlopen(libopenslide.0.dylib, 6): image
not found
--------------------------------------+----------------------
  Reporter:  DavidBAEpstein           |      Owner:  bgilbert
      Type:  defect                   |     Status:  assigned
  Priority:  Normal                   |  Milestone:
 Component:  ports                    |    Version:  2.7.1
Resolution:                           |   Keywords:
      Port:  openslide, py-openslide  |
--------------------------------------+----------------------

Comment (by bgilbert):

 As background info, there are two components here: OpenSlide is a C
 library, and OpenSlide Python is a Python package that uses it.  MacPorts
 has both, conda has both, and pip only has OpenSlide Python.  `import
 openslide` invokes OpenSlide Python and causes it to look for OpenSlide,
 which must be in a directory where Python will find it.  That's the
 problem you've encountered.  MacPorts' Python will look in the MacPorts
 library directory for OpenSlide, while Conda's Python presumably won't.

 I agree that it's safer to stick with one distribution, rather than mixing
 OpenSlide from MacPorts and OpenSlide Python from conda.  A mix //might//
 be made to work if your Python program only uses OpenSlide, since
 OpenSlide and Python may not have any library dependencies in common.  But
 the more libraries your Python program uses, the more likely it is that
 you'll inadvertently try to load, say, both the MacPorts and conda
 versions of the JPEG library into your program.

 **@DavidBAEpstein**, I think it should be okay to install OpenSlide Python
 with pip, so long as that pip matches the distribution you got OpenSlide
 from -- either MacPorts or conda.  I'm glad you were able to get it
 working.

 **@ryandesign**, for the record, the comment text you quoted was dropped
 from that file [https://github.com/openslide/openslide-
 python/commit/b59be96af0fbf7ab73a703caa268fe9d48b5cd4a a while ago].  It
 was originally written before the Python 3 ports
 [https://github.com/macports/macports-
 ports/commit/8c31c1344ae8c8c50ae74388e705a1312f6f9d28 started setting
 DEFAULT_LIBRARY_FALLBACK].

-- 
Ticket URL: <https://trac.macports.org/ticket/63492#comment:12>
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