Resolve Deprecation Warnings

[Mikejmnez]

Description

Running test with python 3.12, I noticed various Deprecation Warnings, one outside the scope of pydap, and the others within pydap. These are

Within scope of pydap:

• pkg_resources. Largely resolved by Solve pkg_resources DeprecationWarning #290, but care must be taken about the way namespaces are being discovered & imported with pydap (pydap/handlers/lib.py).

src/pydap/handlers/lib.py:19
  ../pydap/src/pydap/handlers/lib.py:19: DeprecationWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html
    import pkg_resources

../mambaforge/envs/pydap_tests/lib/python3.12/site-packages/pkg_resources/__init__.py:2832
  ../mambaforge/envs/pydap_tests/lib/python3.12/site-packages/pkg_resources/__init__.py:2832: DeprecationWarning: Deprecated call to `pkg_resources.declare_namespace('paste')`.
  Implementing implicit namespace packages (as specified in PEP 420) is preferred to `pkg_resources.declare_namespace`. See https://setuptools.pypa.io/en/latest/references/keywords.html#keyword-namespace-packages
    declare_namespace(pkg)

• for val in sequence. This is internal within pydap >= 3.4.

  ../pydap/src/pydap/model.py:643: PendingDeprecationWarning: Starting with pydap 3.4 ``for val in sequence: ...`` will give children names. To iterate over data the construct ``for val in sequence.iterdata(): ...``is available now and will be supported in thefuture to iterate over data.

• thread locks. This is associated with fork vs spawn when using multiprocessing, as described in pydap#292. This is an important one to figure out.

  ../mambaforge/envs/pydap_tests/lib/python3.12/multiprocessing/popen_fork.py:66: DeprecationWarning: This process (pid=30734) is multi-threaded, use of fork() may lead to deadlocks in the child.
    self.pid = os.fork()

• Conversion of an array with ndim > 0 to a scalar is deprecated for numpy > 1.25

  ../pydap/src/pydap/lib.py:161: DeprecationWarning: Conversion of an array with ndim > 0 to a scalar is deprecated, and will error in future. Ensure you extract a single element from your array before performing this operation. (Deprecated NumPy 1.25.)
    return "%.6g" % obj

• Unverified HTTPS request

src/pydap/tests/test_server_devel_ssl.py::test_verify_open_url
  ../mambaforge/envs/pydap_tests/lib/python3.12/site-packages/urllib3/connectionpool.py:1103: InsecureRequestWarning: Unverified HTTPS request is being made to host '0.0.0.0'. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#tls-warnings

Outside scope of pydap

• cgi is deprecated

../mambaforge/envs/pydap_tests/lib/python3.12/site-packages/webob/compat.py:5
  ../mambaforge/envs/pydap_tests/lib/python3.12/site-packages/webob/compat.py:5: DeprecationWarning: 'cgi' is deprecated and slated for removal in Python 3.13
    from cgi import parse_header

Solution method

For package outside of scope of pydap: It will surely take sometime before python 3.13 arrives. It looks like the devs of webob are aware of this via webob#437. We should simply suppress this Deprecation warning on the pyproject.toml (otherwise the warning will appear in other packages that may depend on pydap).

For the other ones, I will spend some time. Some of them can be fixed easily. But two or more will require some effort.