python-native-libs

Helpers for setting up an embedded Python interpreter

Overview

The canonical use case is to help set up ScalaPy to point to a specific Python installation by attempting to infer the correct configuration properties used by ScalaPy during the initialization of the embedded Python interpreter. This could potentially see usage outside of ScalaPy too since these properties are relevant to embedded Python in general.

Usage

By default Python checks for the python3 executable (or python if python3 is not found) on PATH

importai.kien.python.Pythonvalpython=Python()
// python: Python = ai.kien.python.Python@5eb35f5d
python.nativeLibrary
// res0: util.Try[String] = Success(value = "python3.9")
python.nativeLibraryPaths
// res1: util.Try[Seq[String]] = Success(// value = ArraySeq(// "/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib/python3.9/config-3.9-darwin",// "/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib"// )// )
python.scalapyProperties
// res2: util.Try[Map[String, String]] = Success(// value = Map(// "jna.library.path" -> "/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib/python3.9/config-3.9-darwin:/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib",// "scalapy.python.library" -> "python3.9",// "scalapy.python.programname" -> "/usr/local/opt/python@3.9/bin/python3.9"// )// )
python.ldflags
// res3: util.Try[Seq[String]] = Success(// value = ArraySeq(// "-L/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib/python3.9/config-3.9-darwin",// "-L/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib",// "-lpython3.9",// "-ldl",// "-framework",// "CoreFoundation"// )// )

You can point it towards a specific Python installation by passing the path to the interpreter executable to Python

valpython=Python("/usr/bin/python3")
// python: Python = ai.kien.python.Python@eb0b5d0
python.nativeLibrary
// res4: util.Try[String] = Success(value = "python3.9")
python.nativeLibraryPaths
// res5: util.Try[Seq[String]] = Success(// value = ArraySeq(// "/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib/python3.9/config-3.9-darwin",// "/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib"// )// )
python.scalapyProperties
// res6: util.Try[Map[String, String]] = Success(// value = Map(// "jna.library.path" -> "/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib/python3.9/config-3.9-darwin:/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib",// "scalapy.python.library" -> "python3.9",// "scalapy.python.programname" -> "/usr/local/opt/python@3.9/bin/python3.9"// )// )
python.ldflags
// res7: util.Try[Seq[String]] = Success(// value = ArraySeq(// "-L/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib/python3.9/config-3.9-darwin",// "-L/usr/local/opt/python@3.9/Frameworks/Python.framework/Versions/3.9/lib",// "-lpython3.9",// "-ldl",// "-framework",// "CoreFoundation"// )// )

See docs/details.md to see the full list of these properties and what they mean.

scalapyProperties contains the system properties used by ScalaPy. For example, to set up ScalaPy to use the Python located at /usr/bin/python3 in Ammonite or Almond run

import$ivy.`ai.kien::python-native-libs:<version>`import$ivy.`me.shadaj::scalapy-core:<scalapy_version>`importai.kien.python.PythonPython("/usr/bin/python3").scalapyProperties.fold(
ex => println(s"Error while getting ScalaPy properties: $ex"),
props => props.foreach { case(k, v) =>System.setProperty(k, v) }
)
importme.shadaj.scalapy.py
println(py.module("sys").version)