github action fails to build font as pycairo fails to build with pip - must include dependancy in setup in github/workflows/build.yml

[mitradranirban]

Github actions to build font fails with the following error message

ollecting pycairo==1.27.0
  Downloading pycairo-1.27.0.tar.gz (661 kB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 661.5/661.5 kB 101.8 MB/s eta 0:00:00
  Installing build dependencies: started
  Installing build dependencies: finished with status 'done'
  Getting requirements to build wheel: started
  Getting requirements to build wheel: finished with status 'done'
  Installing backend dependencies: started
  Installing backend dependencies: finished with status 'done'
  Preparing metadata (pyproject.toml): started
  Preparing metadata (pyproject.toml): finished with status 'error'
  error: subprocess-exited-with-error
  
  × Preparing metadata (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [461 lines of output]
      + meson setup /tmp/pip-install-yj149qam/pycairo_5d1bacb569f1426d9bf32a836e24b212 /tmp/pip-install-yj149qam/pycairo_5d1bacb569f1426d9bf32a836e24b212/.mesonpy-nfpua7en -Dbuildtype=release -Db_ndebug=if-release -Db_vscrt=md -Dwheel=true -Dtests=false --native-file=/tmp/pip-install-yj149qam/pycairo_5d1bacb569f1426d9bf32a836e24b212/.mesonpy-nfpua7en/meson-python-native-file.ini
      The Meson build system
      Version: 1.6.0
      Source dir: /tmp/pip-install-yj149qam/pycairo_5d1bacb569f1426d9bf32a836e24b212
      Build dir: /tmp/pip-install-yj149qam/pycairo_5d1bacb569f1426d9bf32a836e24b212/.mesonpy-nfpua7en
      Build type: native build
      Project name: pycairo
      Project version: 1.27.0
      C compiler for the host machine: cc (gcc 13.2.0 "cc (Ubuntu 13.2.0-23ubuntu4) 13.2.0")
      C linker for the host machine: cc ld.bfd 2.42
      Host machine cpu family: x86_64
      Host machine cpu: x86_64
      Program python3 found: YES (/home/runner/work/paribartan/paribartan/venv/bin/python3)
      Compiler for C supports arguments -Wall: YES
      Compiler for C supports arguments -Warray-bounds: YES
      Compiler for C supports arguments -Wcast-align: YES
      Compiler for C supports arguments -Wconversion: YES
      Compiler for C supports arguments -Wextra: YES
      Compiler for C supports arguments -Wformat=2: YES
      Compiler for C supports arguments -Wformat-nonliteral: YES
      Compiler for C supports arguments -Wformat-security: YES
      Compiler for C supports arguments -Wimplicit-function-declaration: YES
      Compiler for C supports arguments -Winit-self: YES
      Compiler for C supports arguments -Winline: YES
      Compiler for C supports arguments -Wmissing-format-attribute: YES
      Compiler for C supports arguments -Wmissing-noreturn: YES
      Compiler for C supports arguments -Wnested-externs: YES
      Compiler for C supports arguments -Wold-style-definition: YES
      Compiler for C supports arguments -Wpacked: YES
      Compiler for C supports arguments -Wpointer-arith: YES
      Compiler for C supports arguments -Wreturn-type: YES
      Compiler for C supports arguments -Wshadow: YES
      Compiler for C supports arguments -Wsign-compare: YES
      Compiler for C supports arguments -Wstrict-aliasing: YES
      Compiler for C supports arguments -Wundef: YES
      Compiler for C supports arguments -Wunused-but-set-variable: YES
      Compiler for C supports arguments -Wswitch-default: YES
      Compiler for C supports arguments -Wno-missing-field-initializers: YES
      Compiler for C supports arguments -Wno-unused-parameter: YES
      Compiler for C supports arguments -fno-strict-aliasing: YES
      Compiler for C supports arguments -fvisibility=hidden: YES
      Found pkg-config: YES (/usr/bin/pkg-config) 1.8.1
      Found CMake: /usr/local/bin/cmake (3.31.1)
      Run-time dependency cairo found: NO (tried pkgconfig and cmake)
      
      ../cairo/meson.build:31:12: ERROR: Dependency "cairo" not found, tried pkgconfig and cmake
      
      A full log can be found at /tmp/pip-install-yj149qam/pycairo_5d1bacb569f1426d9bf32a836e24b212/.mesonpy-nfpua7en/meson-logs/meson-log.txt
==== CI platform detected, click here for meson-log.txt contents. ====
      
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
error: metadata-generation-failed

× Encountered error while generating package metadata.
╰─> See above for output.

note: This is an issue with the package mentioned above, not pip.

However if I modify .github/workflows/build.yml as below

18 -       sudo apt-get install ttfautohint
18 +        sudo apt-get install ttfautohint libcairo2-dev python3-cairo-dev pkg-config python3-dev

Then Actions work and font is built.

I think build.yml should be updated to prevent build failure

[simoncozens]

It's good that it can be built from sources, but the ideal would be to have pycairo wheels.

[mitradranirban]

pycairo is not provided as a binary package but a source package in pypi. So the wheel must be compiled. It can be cached till new version of OS is there is the runner.