Add optional option to RustExtension

CHANGES.rst

@@ -1,6 +1,11 @@
 CHANGES
 =======
 
+0.6.2 (2017-07-31)
+------------------
+
+- Add `optional` option to `RustExtension` #16
+
 0.6.1 (2017-06-30)
 ------------------
 

README.rst

@@ -80,6 +80,9 @@ You can define rust extension with `RustExtension` class:
                        `Binding.RustCPython` uses rust-cpython
                        `Binding.NoBinding` uses no binding.
 
+    :param bool optional: if it is true, a build failure in the extension will not abort the build process,
+                          but instead simply not install the failing extension.
+
 Commands
 --------
 

setuptools_rust/build.py

@@ -7,7 +7,7 @@
 from distutils.cmd import Command
 from distutils.errors import (
     CompileError, DistutilsExecError, DistutilsFileError,
-    DistutilsPlatformError)
+    DistutilsPlatformError, DistutilsSetupError)
 
 from .extension import RustExtension
 from .utils import cpython_feature, get_rust_version
@@ -166,10 +166,18 @@ def run(self):
         version = get_rust_version()
 
         for ext in self.extensions:
-            rust_version = ext.get_rust_version()
-            if rust_version is not None and version not in rust_version:
-                raise DistutilsPlatformError(
-                    "Rust %s does not match extension requirement %s" % (
-                        version, ext.rust_version))
-
-            self.build_extension(ext)
+            try:
+                rust_version = ext.get_rust_version()
+                if rust_version is not None and version not in rust_version:
+                    raise DistutilsPlatformError(
+                        "Rust %s does not match extension requirement %s" % (
+                            version, ext.rust_version))
+
+                self.build_extension(ext)
+            except (DistutilsSetupError, DistutilsFileError, DistutilsExecError,
+                    DistutilsPlatformError, CompileError) as e:
+                if not ext.optional:
+                    raise
+                else:
+                    print('Build optional Rust extension %s failed.' % ext.name)
+                    print(str(e))

setuptools_rust/extension.py

@@ -35,17 +35,22 @@ class RustExtension:
         Binding.PyO3 uses PyO3
         Binding.RustCPython uses Rust CPython.
         Binding.NoBinding uses no binding.
+      optional : bool
+        if it is true, a build failure in the extension will not abort the build process,
+        but instead simply not install the failing extension.
     """
 
     def __init__(self, name, path,
                  args=None, features=None, rust_version=None,
-                 quiet=False, debug=None, binding=Binding.PyO3):
+                 quiet=False, debug=None, binding=Binding.PyO3,
+                 optional=False):
         self.name = name
         self.args = args
         self.binding = binding
         self.rust_version = rust_version
         self.quiet = quiet
         self.debug = debug
+        self.optional = optional
 
         if features is None:
             features = []