netcdf-c/nc_test
Dennis Heimbigner 231ae96c4b Add support for Zarr string type to NCZarr
* re: https://github.com/Unidata/netcdf-c/pull/2278
* re: https://github.com/Unidata/netcdf-c/issues/2485
* re: https://github.com/Unidata/netcdf-c/issues/2474

This PR subsumes PR https://github.com/Unidata/netcdf-c/pull/2278.
Actually is a bit an omnibus covering several issues.

## PR https://github.com/Unidata/netcdf-c/pull/2278
Add support for the Zarr string type.
Zarr strings are restricted currently to be of fixed size.
The primary issue to be addressed is to provide a way for user to
specify the size of the fixed length strings. This is handled by providing
the following new attributes special:
1. **_nczarr_default_maxstrlen** —
This is an attribute of the root group. It specifies the default
maximum string length for string types. If not specified, then
it has the value of 64 characters.
2. **_nczarr_maxstrlen** —
This is a per-variable attribute. It specifies the maximum
string length for the string type associated with the variable.
If not specified, then it is assigned the value of
**_nczarr_default_maxstrlen**.

This PR also requires some hacking to handle the existing netcdf-c NC_CHAR
type, which does not exist in zarr. The goal was to choose numpy types for
both the netcdf-c NC_STRING type and the netcdf-c NC_CHAR type such that
if a pure zarr implementation read them, it would still work and an
NC_CHAR type would be handled by zarr as a string of length 1.

For writing variables and NCZarr attributes, the type mapping is as follows:
* "|S1" for NC_CHAR.
* ">S1" for NC_STRING && MAXSTRLEN==1
* ">Sn" for NC_STRING && MAXSTRLEN==n

Note that it is a bit of a hack to use endianness, but it should be ok since for
string/char, the endianness has no meaning.

For reading attributes with pure zarr (i.e. with no nczarr
atribute types defined), they will always be interpreted as of
type NC_CHAR.

## Issue: https://github.com/Unidata/netcdf-c/issues/2474
This PR partly fixes this issue because it provided more
comprehensive support for Zarr attributes that are JSON valued expressions.
This PR still does not address the problem in that issue where the
_ARRAY_DIMENSION attribute is incorrectly set. Than can only be
fixed by the creator of the datasets.

## Issue: https://github.com/Unidata/netcdf-c/issues/2485
This PR also fixes the scalar failure shown in this issue.
It generally cleans up scalar handling.
It also adds a note to the documentation describing that
NCZarr supports scalars while Zarr does not and also how
scalar interoperability is achieved.

## Misc. Other Changes
1. Convert the nczarr special attributes and keys to be all lower case. So "_NCZARR_ATTR" now used "_nczarr_attr. Support back compatibility for the upper case names.
2. Cleanup my too-clever-by-half handling of scalars in libnczarr.
2022-08-27 20:21:13 -06:00
..
bad_cdf5_begin.nc add a test program to read a CDF-5 file with a corrupted header 2017-09-16 14:04:39 -05:00
CMakeLists.txt Add support for Zarr string type to NCZarr 2022-08-27 20:21:13 -06:00
error.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
error.h More copyright stanza updates. 2018-12-06 14:56:42 -07:00
f03tst_open_mem.nc Fix use of 'int' to represent 'hid_t' that caused HDF5 1.10 to fail. 2018-05-30 14:47:37 -06:00
large_files.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
make_test_file.sh Swapped /bin/bash for /bin/sh to test on osx. 2018-08-12 23:01:08 -06:00
Makefile.am Add support for Zarr string type to NCZarr 2022-08-27 20:21:13 -06:00
nc_enddef.cdl Fix additional S3 support issues 2021-10-29 20:06:37 -06:00
nc_sync.cdl moving to trunk subdir 2010-06-03 13:24:43 +00:00
nc_test.c Turn verbose output on in nc_test. 2021-06-16 16:34:06 -06:00
nc_test.html moving to trunk subdir 2010-06-03 13:24:43 +00:00
quick_large_files.c Spelling fixes 2019-09-18 08:03:01 -06:00
ref_tst_diskless2.cdl - Implemented diskless files for both netcdf classic and extended. 2012-03-26 01:34:32 +00:00
ref_tst_diskless3_create.cdl Fix cmake X mmap 2019-04-19 20:32:26 -06:00
ref_tst_diskless3_open.cdl Fix cmake X mmap 2019-04-19 20:32:26 -06:00
ref_tst_http_nc3.cdl Use the built-in HDF5 byte-range reader, if available. 2020-09-24 14:33:58 -06:00
ref_tst_http_nc4a.cdl Use the built-in HDF5 byte-range reader, if available. 2020-09-24 14:33:58 -06:00
ref_tst_http_nc4b.cdl Mostly revert the filter code to reduce its complexity of use. 2020-09-27 12:43:46 -06:00
ref_tst_http_nc4c.cdl Fix additional S3 support issues 2021-10-29 20:06:37 -06:00
run_cdf5.sh add another test program to check if a CDF-5 file has a corrupted header 2017-09-16 14:30:09 -05:00
run_diskless2.sh Two fixes for the price of one! 2022-04-28 15:51:20 -06:00
run_diskless5.sh typo 2017-05-03 10:19:35 -06:00
run_diskless.sh Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
run_inmemory.sh Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
run_mmap.sh Fix cmake X mmap 2019-04-19 20:32:26 -06:00
run_pnetcdf_tests.sh.in Update to default --with-plugin-dir to yes 2022-05-24 20:05:19 -06:00
t_nc_p5.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
t_nc.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
test_byterange.sh Add support for Zarr string type to NCZarr 2022-08-27 20:21:13 -06:00
test_get.m4 Docs migration 2021-11-11 10:47:49 -07:00
test_put.m4 Fix an accidentally-introduced bug. 2021-07-13 12:07:56 -06:00
test_read.m4 Eliminate a lot of 'result of operation is undefined or garbage' errors reported by static analysis. These errors appeared to be false positives as there was logic that should prevent their occurance, but it's possible that optimization would result in these error states occuring. 2021-07-12 16:40:27 -06:00
test_write.m4 Eliminate a lot of 'result of operation is undefined or garbage' errors reported by static analysis. These errors appeared to be false positives as there was logic that should prevent their occurance, but it's possible that optimization would result in these error states occuring. 2021-07-12 16:40:27 -06:00
testnc3perf.c cleaned up makefile.am, added config.h to some tests 2019-01-02 05:31:15 -07:00
tests.h windows: detect Windows using the correct define name 2019-11-07 07:55:47 -05:00
tst_addvar.c cleaned up makefile.am, added config.h to some tests 2019-01-02 05:31:15 -07:00
tst_atts3.c fixed comment 2020-08-12 07:59:45 -06:00
tst_big_rvar.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_big_var2.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_big_var6.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_big_var.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_byterange.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_cdf5_begin.c cleaned up makefile.am, added config.h to some tests 2019-01-02 05:31:15 -07:00
tst_cdf5format.c Added int i and j declarations 2019-02-12 15:10:39 +00:00
tst_def_var_fill.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_default_format_pnetcdf.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_default_format.c Merge remote-tracking branch 'origin/license_update.wif' into pr-aggregation.wif 2018-12-11 17:08:21 -05:00
tst_diskless2.c Fix cmake X mmap 2019-04-19 20:32:26 -06:00
tst_diskless3.c Spelling fixes 2019-09-18 08:03:01 -06:00
tst_diskless4.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
tst_diskless5.c Improve UTF8 Support On Windows 2022-02-08 20:53:30 -07:00
tst_diskless5.cdl Add testcase 2017-05-03 09:58:49 -06:00
tst_diskless6.c fixed warnings 2022-04-26 05:31:07 -06:00
tst_diskless.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_err_enddef.c Addendum: This PR has been extended to include 2021-04-02 18:39:50 -06:00
tst_formats.c Mostly revert the filter code to reduce its complexity of use. 2020-09-27 12:43:46 -06:00
tst_formatx_pnetcdf.c warnings fixes 2019-01-03 07:07:13 -07:00
tst_global_fillval.c Merge remote-tracking branch 'origin/license_update.wif' into pr-aggregation.wif 2018-12-11 17:08:21 -05:00
tst_inmemory.c Improve UTF8 Support On Windows 2022-02-08 20:53:30 -07:00
tst_inq_type.c merged ejh_test_null_vars_stride this time I mean it! 2019-01-03 06:36:58 -07:00
tst_large_cdf5.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_large.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_max_var_dims.c cleaned up makefile.am, added config.h to some tests 2019-01-02 05:31:15 -07:00
tst_meta.c cleaned up makefile.am, added config.h to some tests 2019-01-02 05:31:15 -07:00
tst_misc.c Improve UTF8 Support On Windows 2022-02-08 20:53:30 -07:00
tst_names.c Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
tst_nofill2.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
tst_nofill3.c Spelling fixes 2019-09-18 08:03:01 -06:00
tst_nofill.c fixing some issuses of pnetcdf tests in nc_test 2022-04-09 13:52:29 -06:00
tst_norm.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
tst_open_cdf5.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
tst_open_mem.c Remove need for HDF5-1.6 API being defined 2021-04-28 13:59:24 -06:00
tst_parallel2.c More copyright stanza updates. 2018-12-06 14:56:42 -07:00
tst_pnetcdf.c fixed problems running mpi-enabled tests with --enable-pnetcdf in nc_test 2022-04-09 14:27:13 -06:00
tst_small.c Spelling fixes 2019-09-18 08:03:01 -06:00
tst_utf8_phrases.c Spelling fixes 2019-09-18 08:03:01 -06:00
tst_utf8_validate.c Testing a fix for a failure I observed. 2018-12-06 17:46:30 -07:00
util.c Docs migration 2021-11-11 10:47:49 -07:00