Add the ability to set some additional curlopt values via .daprc (aka .dodsrc).
This effects both DAP2 and DAP4 protocols.
Related issues:
[1] re: esupport: KOZ-821332
[2] re: github issue https://github.com/Unidata/netcdf4-python/issues/836
[3] re: github issue https://github.com/Unidata/netcdf-c/issues/1074
1. CURLOPT_BUFFERSIZE: Relevant to [1]. Allow user to set the read/write
buffersizes used by curl.
This is done by adding the following to .daprc (aka .dodsrc):
HTTP.READ.BUFFERSIZE=n
where n is the buffersize in bytes. There is a built-in (to curl)
limit of 512k for this value.
2. CURLOPT_TCP_KEEPALIVE (and CURLOPT_TCP_KEEPIDLE and CURLOPT_TCP_KEEPINTVL):
Relevant (maybe) to [2] and [3]. Allow the user to turn on KEEPALIVE
This is done by adding the following to .daprc (aka .dodsrc):
HTTP.KEEPALIVE=on|n/m
If the value is "on", then simply enable default KEEPALIVE. If the value
is n/m, then enable KEEPALIVE and set KEEPIDLE to n and KEEPINTVL to m.
This relies on the HDF5 capability to
dynamically load compression filters.
Note that a compression filter is just
a subcase of filters.
The primary user-visible changes are as follows:
1. Add a standard header "netcdf_filter.h" that defines
the necessary API extensions
2. Modify ncgen to support two new special attributes
"_Filter_ID" and "_Filter_Parameters" so that compression
can be turned on when creating a file using ncgen.
4. Add a detailed description of filtering support
to the user's guide; see the file filters.md
5. Add a test case directory for this: nc_test4/filter_test.
It is fragile and a ./configure flags (-enable-filter-test)
is defined (default disabled) to shut this off this test
to avoid spurious 'make check' failures.
Note that the HDF5 documentation is not up-to-date, so
much of what is encoded here comes from examining the
actual code in the file H5PL.c in the HDF5 source code.
Specific changes:
1. Add dap4 code: libdap4 and dap4_test.
Note that until the d4ts server problem is solved, dap4 is turned off.
2. Modify various files to support dap4 flags:
configure.ac, Makefile.am, CMakeLists.txt, etc.
3. Add nc_test/test_common.sh. This centralizes
the handling of the locations of various
things in the build tree: e.g. where is
ncgen.exe located. See nc_test/test_common.sh
for details.
4. Modify .sh files to use test_common.sh
5. Obsolete separate oc2 by moving it to be part of
netcdf-c. This means replacing code with netcdf-c
equivalents.
5. Add --with-testserver to configure.ac to allow
override of the servers to be used for --enable-dap-remote-tests.
6. There were multiple versions of nctypealignment code. Try to
centralize in libdispatch/doffset.c and include/ncoffsets.h
7. Add a unit test for the ncuri code because of its complexity.
8. Move the findserver code out of libdispatch and into
a separate, self contained program in ncdap_test and dap4_test.
9. Move the dispatch header files (nc{3,4}dispatch.h) to
.../include because they are now shared by modules.
10. Revamp the handling of TOPSRCDIR and TOPBUILDDIR for shell scripts.
11. Make use of MREMAP if available
12. Misc. minor changes e.g.
- #include <config.h> -> #include "config.h"
- Add some no-install headers to /include
- extern -> EXTERNL and vice versa as needed
- misc header cleanup
- clean up checking for misc. unix vs microsoft functions
13. Change copyright decls in some files to point to LICENSE file.
14. Add notes to RELEASENOTES.md