Prerequisites when building Streamlink on Windows?

[danj2k]

Description

Are there any OS-specific prerequisites for building Streamlink from source on Windows?

When attempting to build Streamlink 6.7.3 (latest stable release) using Python 3.12.3, with the command C:\Python312\Scripts\pip.exe install . while in the streamlink-6.7.3 directory, it gets as far as building plugins JSON data and then fails with the following errors:

      Traceback (most recent call last):
        File "C:\Python312\Lib\site-packages\pip\_vendor\pyproject_hooks\_in_process\_in_process.py", line 353, in <module>
          main()
        File "C:\Python312\Lib\site-packages\pip\_vendor\pyproject_hooks\_in_process\_in_process.py", line 335, in main
          json_out['return_val'] = hook(**hook_input['kwargs'])
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\Python312\Lib\site-packages\pip\_vendor\pyproject_hooks\_in_process\_in_process.py", line 251, in build_wheel
          return _build_backend().build_wheel(wheel_directory, config_settings,
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\build_meta.py", line 410, in build_wheel
          return self._build_with_temp_dir(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\build_meta.py", line 395, in _build_with_temp_dir
          self.run_setup()
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\build_meta.py", line 311, in run_setup
          exec(code, locals())
        File "<string>", line 89, in <module>
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\__init__.py", line 104, in setup
          return distutils.core.setup(**attrs)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\core.py", line 184, in setup
          return run_commands(dist)
                 ^^^^^^^^^^^^^^^^^^
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\core.py", line 200, in run_commands
          dist.run_commands()
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\dist.py", line 969, in run_commands
          self.run_command(cmd)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\dist.py", line 967, in run_command
          super().run_command(command)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\dist.py", line 988, in run_command
          cmd_obj.run()
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\wheel\bdist_wheel.py", line 368, in run
          self.run_command("build")
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\cmd.py", line 316, in run_command
          self.distribution.run_command(command)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\dist.py", line 967, in run_command
          super().run_command(command)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\dist.py", line 988, in run_command
          cmd_obj.run()
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\command\build.py", line 132, in run
          self.run_command(cmd_name)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\cmd.py", line 316, in run_command
          self.distribution.run_command(command)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\dist.py", line 967, in run_command
          super().run_command(command)
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\_distutils\dist.py", line 988, in run_command
          cmd_obj.run()
        File "C:\Users\danar\AppData\Local\Temp\pip-build-env-kl_4vvbt\overlay\Lib\site-packages\setuptools\command\build_py.py", line 67, in run
          self.build_package_data()
        File "C:\Users\danar\Downloads\streamlink-6.7.3\build_backend\commands.py", line 29, in build_package_data
          self._build_plugins_json()
        File "C:\Users\danar\Downloads\streamlink-6.7.3\build_backend\commands.py", line 22, in _build_plugins_json
          data = build()
                 ^^^^^^^
        File "C:\Users\danar\Downloads\streamlink-6.7.3\build_backend\plugins_json.py", line 446, in build
          source = file.read_text()
                   ^^^^^^^^^^^^^^^^
        File "C:\Python312\Lib\pathlib.py", line 1028, in read_text
          return f.read()
                 ^^^^^^^^
        File "C:\Python312\Lib\encodings\cp1252.py", line 23, in decode
          return codecs.charmap_decode(input,self.errors,decoding_table)[0]
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      UnicodeDecodeError: 'charmap' codec can't decode byte 0x8d in position 2010: character maps to <undefined>
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for streamlink
Failed to build streamlink
ERROR: Could not build wheels for streamlink, which is required to install pyproject.toml-based projects

It looks like it is trying to use a wrong code page or something? I tried various tricks that I found / could think of to force UTF-8, such as chcp 65001, installing the win_unicode_console module and including it in sitecustomize.py in site-packages, setting the PYTHONIOENCODING environment variable, but none of these things cleared this error.

Can anyone suggest how to address this? There are reasons I don't want to just use the precompiled Windows binaries, I need to be able to build it from source.

[bastimeyer]

Does this patch fix the issue?

diff --git a/build_backend/plugins_json.py b/build_backend/plugins_json.py
index 70f4e93d..4c81be1d 100644
--- a/build_backend/plugins_json.py
+++ b/build_backend/plugins_json.py
@@ -443,7 +443,7 @@ def build(pluginsdir: Path = DEFAULT_PLUGINSPATH) -> Output:
     for file in pluginsdir.glob("*.py"):
         name = file.name
         plugin = re.sub(r"\.py$", "", name)
-        source = file.read_text()
+        source = file.read_text(encoding="utf-8")
 
         tree = ast.parse(source, str(file))
         visitor = PluginVisitor()

[bastimeyer]

#5990

[danj2k]

Yes, that fixes it. Though, now I have a different problem in that the streamlink.exe that has been generated seems like it's just a stub executable that requires a Python installation. I'd like to be able to create an independent .exe file that can be used on other machines without needing Python installed. I did see there was another repository at https://github.com/streamlink/windows-builds specific to Windows but everything there seems aimed at producing an installer, and it also seems like it downloads the Streamlink source directly from the main repository, I don't see a way to allow it to use a locally built copy?

[bastimeyer]

The .exe you're seeing on your system is a launcher generated by pip / distlib. This is how it works on Windows and how pip makes entry points of python distributions available.

There are alternative ways to package python distributions in "single executables", but I don't have any experience with this and I also think that this won't work with Streamlink's plugin system. I also believe that this is a deprecated way of packaging Python distributions.

streamlink/windows-builds provides installers as well as "portable archives" that bundles a Python environment and an FFmpeg build, as you can read in its README.md, as well as in Streamlink's docs:
https://streamlink.github.io/latest/install.html#windows-binaries