Our python interpreter uses ncclient which depends on lxml egg, but does not explicitly specify to use that lxml from slapos component.
Until now we were lucky because slapos-cookbook depends on the correct lxml and
we have slapos-cookbook as the second entry in the part list with only
template preceding it.
However I needed to use pythonwitheggs inside that template and then got the build failure, because now pythonwitheggs was built before slapos-cookbook and tried to use lxml without slapos component:
INFO Building without Cython.
INFO Error: Please make sure the libxml2 and libxslt development packages are installed.
INFO An error occurred when trying to install lxml 4.9.1. Look above this message for any errors that were output by easy_install.
INFO While:
INFO Installing pythonwitheggs.
INFO Base installation request: 'websocket-client', 'pynacl', 'bcrypt', 'xmltodict', 'ncclient'
INFO Requirement of ncclient==0.6.13: six
INFO Requirement of ncclient==0.6.13: lxml>=3.3.0
INFO Requirement of ncclient==0.6.13: paramiko>=1.15.0
INFO Requirement of ncclient==0.6.13: setuptools>0.6
INFO Requirement of bcrypt==3.1.4: six>=1.4.1
INFO Requirement of bcrypt==3.1.4: cffi>=1.1
INFO Requirement of pynacl==1.3.0: cffi>=1.4.1
INFO Requirement of pynacl==1.3.0: six
INFO Getting distribution for 'lxml==4.9.1'.
INFO Error: Couldn't install: lxml 4.9.1-> Fix it by explicitly specifying in-slapos lxml egg to be used.
/cc @jhuge, @lu.xu, @xavier_thompson, @Daetalus