"dns error: failed to lookup address information" when using extra-index-urls

[rgaiacs]

When I run

$ pixi init && pixi add python pip
✔ Created /tmp/tmp.o1YIDzoZrJ/pixi.toml
✔ Added python >=3.13.7,<3.14
✔ Added pip >=25.2,<26

and

$ pixi shell
$ python -m pip install --extra-index-url https://git.gesis.org/api/v4/projects/rse%2Fgesis-sphinx-theme/packages/pypi/simple gesis-sphinx-theme
Looking in indexes: https://pypi.org/simple, https://git.gesis.org/api/v4/projects/rse%2Fgesis-sphinx-theme/packages/pypi/simple
...
Installing collected packages: urllib3, sphinxcontrib-serializinghtml, sphinxcontrib-qthelp, sphinxcontrib-jsmath, sphinxcontrib-htmlhelp, sphinxcontrib-devhelp, sphinxcontrib-applehelp, snowballstemmer, roman-numerals-py, Pygments, packaging, MarkupSafe, imagesize, idna, docutils, charset_normalizer, certifi, babel, alabaster, requests, Jinja2, Sphinx, gesis-sphinx-theme
Successfully installed Jinja2-3.1.6 MarkupSafe-3.0.2 Pygments-2.19.2 Sphinx-8.2.3 alabaster-1.0.0 babel-2.17.0 certifi-2025.8.3 charset_normalizer-3.4.3 docutils-0.21.2 gesis-sphinx-theme-2025.2.26 idna-3.10 imagesize-1.4.1 packaging-25.0 requests-2.32.5 roman-numerals-py-3.1.0 snowballstemmer-3.0.1 sphinxcontrib-applehelp-2.0.0 sphinxcontrib-devhelp-2.0.0 sphinxcontrib-htmlhelp-2.1.0 sphinxcontrib-jsmath-1.0.1 sphinxcontrib-qthelp-2.0.0 sphinxcontrib-serializinghtml-2.0.0 urllib3-2.5.0

all works as expected. I'm trying to add the gesis-sphinx-theme package from https://git.gesis.org/api/v4/projects/rse%2Fgesis-sphinx-theme/packages/pypi/simple to my project.

I followed the information in "Alternative registries" and "pypi-dependencies" to have the configuration file as

[workspace]
authors = ["Raniere Gaia Costa da Silva <[email protected]>"]
channels = ["conda-forge"]
name = "tmp.o1YIDzoZrJ"
platforms = ["linux-64"]
version = "0.1.0"

[tasks]

[dependencies]
python = ">=3.13.7,<3.14"
pip = ">=25.2,<26"

[pypi-options]
extra-index-urls = ["https://git.gesis.org/api/v4/projects/rse%2Fgesis-sphinx-theme/packages/pypi/simple"]

[pypi-dependencies]
gesis-sphinx-theme = "==1.3.0"

When I run

pixi shell

I end with the following error

Error:   × failed to solve the pypi requirements of 'default' 'linux-64'
  ├─▶ failed to resolve pypi dependencies
  ├─▶ Failed to fetch: `https://git.gesis.org/api/v4/projects/rse%2Fgesis-sphinx-theme/packages/pypi/simple/gesis-sphinx-theme/`
  ├─▶ Could not connect, are you offline?
  ├─▶ Request failed after 3 retries
  ├─▶ error sending request for url (https://git.gesis.org/api/v4/projects/rse%2Fgesis-sphinx-theme/packages/pypi/simple/gesis-sphinx-theme/)
  ├─▶ client error (Connect)
  ├─▶ dns error: failed to lookup address information: Name does not resolve
  ╰─▶ failed to lookup address information: Name does not resolve

Could I have a confirmation that my problem is the same reported in #1882?