Merge pull request #4 from billsacks/nc_via_lfs

Store netCDF files via Git LFS

.gitattributes

@@ -4,3 +4,4 @@
 *.jpeg filter=lfs diff=lfs merge=lfs -text
 *.gif filter=lfs diff=lfs merge=lfs -text
 *.pdf filter=lfs diff=lfs merge=lfs -text
+*.nc filter=lfs diff=lfs merge=lfs -text

.gitignore

@@ -13,8 +13,10 @@ manage_externals.log
 **/.svn/**
 .svn/
 
-# binary files
+# netcdf files
 *.nc
+# but don't ignore netcdf files here:
+!/python/ctsm/test/testinputs/*.nc
 
 # editor files
 *.swp

.lfsconfig

@@ -1,2 +1,7 @@
 [lfs]
-        fetchexclude = *
+	# We auto-fetch any netCDF files, because they are needed for
+	# running tests; however, we do NOT auto-fetch other binary
+	# files, in particular image files that are part of the
+	# documentation source (these are fetched as part of the
+	# documentation build process).
+	fetchinclude = *.nc

python/ctsm/test/testinputs/README.md

@@ -0,0 +1,35 @@
+Any netCDF files in this directory (and elsewhere in the repository) should be
+stored via Git LFS (Large File Support). To retrieve any netCDF files, or to add
+or modify any netCDF files, you will need to install the Git LFS tool.
+
+Installing Git LFS on your machine is a two-step process; step (1) needs to be
+done once per machine, and step (2) needs to be done once per user:
+1. Install the Git LFS tool: Follow the instructions on the [Git LFS
+page](https://git-lfs.github.com/) for installing Git LFS on your platform.
+  - On cheyenne, Git LFS is already available as long as you are using a git
+    module rather than the default system-level git. So just make sure that you
+    are always using git via a git module (`module load git`).
+  - On a Mac using homebrew, this can be done with `brew install git-lfs`.
+2. Set up your git configuration to use Git LFS by running: `git lfs install`
+   (this will add a few lines to your `.gitconfig` file in your home directory).
+   (If you're not sure whether you have already done this, it is safe to rerun
+   that command to be sure.)
+
+If any netCDF file appears to be a text file like this:
+
+```
+version https://git-lfs.github.com/spec/v1
+oid sha256:df03c76138bbdcdd12497a4bb0a86591283d1d8ef90cba80d823660f549381c0
+size 896
+```
+
+then that is a sign that you may not have Git LFS installed. You can first try
+running "git lfs pull". If that doesn't work, then install Git LFS as documented
+above.
+
+For more information on using Git LFS with CTSM, search for lfs here:
+<https://github.com/ESCOMP/CTSM/wiki/Directions-for-editing-CLM-documentation-on-github-and-sphinx>.
+Most of the notes about using Git LFS for the documentation's image files apply
+here as well, although (in contrast to image files) netCDF files *are* pulled
+down by default, so you usually should *not* need to explicitly run `git lfs
+pull` to get new or updated netCDF files.