add optional [data] dependencies to give access to data behind the ca…

…talog

pyproject.toml

@@ -19,11 +19,24 @@ classifiers = [
 dependencies = [
     "requests",
     "pyyaml",
-    "intake!=0.6.1",  # due to lacking jinja2 dependency
+    "intake!=0.6.1,<2.0.0",  # due to lacking jinja2 dependency
     "aiohttp",  # required by intake to access catalogs via http
+    "fsspec>=0.7.4",
     "ipfsspec",
 ]
 dynamic = ["version"]
 
+[project.optional-dependencies]
+data = [
+    # the most recent version of intake-xarray (v3.2.2) only supports the OPeNDAP
+    # servers by URS and ESGF, the fork bellow allows for connecting to general OPeNDAP servers
+    "xarray",
+    "zarr",
+    "netcdf4!=1.5.4,!=1.5.5,!=1.5.5.1,!=1.6.0,!=1.6.1,!=1.6.2,!=1.6.3,!=1.6.4", # this is due to https://github.com/Unidata/netcdf4-python/issues/1052 and a CURL error in 1.6.0 (https://github.com/Unidata/netcdf-c/issues/2459) and https://github.com/eurec4a/eurec4a-intake/issues/121
+    "s3fs",
+    "requests",
+    "intake-xarray>=0.3.2",
+]
+
 [tool.setuptools_scm]
 version_file = "eurec4a/_version.py"