FAQ¶

Requests¶

Q: I'm getting an SSL Error when making a request to url containing cern.ch.

A: If you run into SSL errors with CERN websites, you might need the CERN certificate chain to sign the certificates correctly. Just add a verify keyword into your calls:

client.get(..., verify=itkdb.data / "CERN_chain.pem")

and it should work.

Q: How do I upload a file to EOS?

A: To upload a file to EOS, you need to install this package with the eos feature. Then refer to some examples for usage.

Q: I got a The token is not yet valid (nbf) error when trying to authenticate. How do I fix this?

A: If you receive an error like so

Traceback (most recent call last):
...
jose.exceptions.JWTClaimsError: The token is not yet valid (nbf)

then the indication here is that the machine running the code has a clock that is not properly synced to the timeserver. You will need to figure out how to re-sync your clock as it is a security issue.

Q: I got an ImportError related to pycurl and libcurl. How do I fix this?

A: If you try running itkdb and run into an issue like:

Traceback (most recent call last):
...
ImportError: pycurl: libcurl link-time ssl backends (secure-transport, openssl) do not include compile-time ssl backend (none/other)

You will need to reinstall pycurl and force re-compilation. This can be done by first checking the config for curl on your machine:

$ curl-config --features
AsynchDNS
GSS-API
HTTPS-proxy
IPv6
Kerberos
Largefile
MultiSSL
NTLM
NTLM_WB
SPNEGO
SSL
UnixSockets
alt-svc
libz

and then setting the appropriate compile flags. For example, the above shows I have SSL enabled, if I have openssl then...

$ brew info openssl
...
...

For compilers to find openssl@3 you may need to set:
  export LDFLAGS="-L/usr/local/opt/openssl@3/lib"
  export CPPFLAGS="-I/usr/local/opt/openssl@3/include"

...

$ export LDFLAGS="-L/usr/local/opt/openssl@3/lib"
$ export CPPFLAGS="-I/usr/local/opt/openssl@3/include"
$ python -m pip install --no-cache-dir --compile --ignore-installed --install-option="--with-openssl" pycurl

$ lsetup "views dev4 latest/x86_64-centos7-gcc11-opt"
$ python3 -m venv venv
$ source venv/bin/activate

$ export LDFLAGS="-L/usr/local/lib/openssl"
$ export CPPFLAGS="-I/usr/local/include/openssl"
$ export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/lib/pkgconfig/
$ python -m pip install --no-cache-dir --compile --ignore-installed --install-option="--with-nss" pycurl

$ python3 -m venv venv
$ source venv/bin/activate

$ export LDFLAGS="-L/usr/lib64/openssl"
$ export CPPFLAGS="-I/usr/include/openssl"
$ export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/lib64/pkgconfig/
$ python -m pip install --no-cache-dir --compile \
                        --ignore-installed \
                        --install-option="--with-nss" pycurl

$ lsetup "views LCG_105 x86_64-el9-gcc11-opt"
$ python3 -m venv venv
$ source venv/bin/activate

$ export LDFLAGS="-L/usr/local/lib/openssl"
$ export CPPFLAGS="-I/usr/local/include/openssl"
$ export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/lib/pkgconfig/
$ python -m pip install --no-cache-dir --compile --ignore-installed --install-option="--with-nss" pycurl

Additional note that if you have pip >= 23.0, you will need to modify the commands above to supply:

--no-use-pep517 --global-option="--with..."

instead of using --install-option which is deprecated in favor of --global-option, and disabling the use of PEP517 to allow the use of --global-option. An example command with this is below:

python -m pip install --no-cache-dir --compile \
                      --ignore-installed --no-use-pep517 \
                      --global-option="--with-openssl" pycurl

Also be sure that you have the curl headers installed (e.g. via libcurl-devel) on your machine.

Developing¶

Q: How do I update a cassette for a test to include new requests to the database that I added in as functionality in itkdb?

A: You can do so like below's steps. First you need to generate a temporary authenticated client to use for all other tests, but this cassette won't be committed. Then you can generate the new cassette for the test that is failing. The example below is for integration/test_tests.py:

$ rm tests/integration/cassettes/test_user.test_user_good_login.json
$ rm tests/integration/cassettes/test_tests.test_duplicate_test_run.json
$ pytest tests/integration/test_user.py
$ pytest tests/integration/test_tests.py
$ git add tests/integration/cassettes/test_tests.test_duplicate_test_run.json
$ git commit -m "update cassette for test_duplicate_test_run"

Potpourri¶

Q: I'm still stuck and I don't see my question here.

A: I'm still working on fleshing out the FAQs. Check back soon. In the meantime, file an issue.