chore(python): Use src/ layout for python package (#234)

Follow-up on #117, moving
back to a src layout
(https://packaging.python.org/en/latest/discussions/src-layout-vs-flat-layout/)

.github/workflows/python.yaml

@@ -74,10 +74,11 @@ jobs:
           pushd python
 
           # Build with Cython + gcc coverage options
+          pip install -e .
           NANOARROW_PYTHON_COVERAGE=1 python setup.py build_ext --inplace
 
           # Run tests + coverage.py (generates .coverage + coverage.xml files)
-          python -m pytest --cov ./nanoarrow
+          python -m pytest --cov ./src/nanoarrow
           python -m coverage xml
 
       - name: Upload coverage to codecov

python/.gitignore

@@ -16,10 +16,10 @@
 # specific language governing permissions and limitations
 # under the License.
 
-nanoarrow/nanoarrow.c
-nanoarrow/nanoarrow.h
-nanoarrow/nanoarrow_c.pxd
-nanoarrow/*.c
+src/nanoarrow/nanoarrow.c
+src/nanoarrow/nanoarrow.h
+src/nanoarrow/nanoarrow_c.pxd
+src/nanoarrow/*.c
 
 # Byte-compiled / optimized / DLL files
 __pycache__/

python/MANIFEST.in

@@ -16,6 +16,6 @@
 # under the License.
 
 exclude bootstrap.py
-include nanoarrow/nanoarrow.c
-include nanoarrow/nanoarrow.h
-include nanoarrow/nanoarrow_c.pxd
+include src/nanoarrow/nanoarrow.c
+include src/nanoarrow/nanoarrow.h
+include src/nanoarrow/nanoarrow_c.pxd

python/bootstrap.py

@@ -145,8 +145,8 @@ def copy_or_generate_nanoarrow_c():
     this_dir = os.path.abspath(os.path.dirname(__file__))
     source_dir = os.path.dirname(this_dir)
 
-    maybe_nanoarrow_h = os.path.join(this_dir, 'nanoarrow/nanoarrow.h')
-    maybe_nanoarrow_c = os.path.join(this_dir, 'nanoarrow/nanoarrow.c')
+    maybe_nanoarrow_h = os.path.join(this_dir, 'src/nanoarrow/nanoarrow.h')
+    maybe_nanoarrow_c = os.path.join(this_dir, 'src/nanoarrow/nanoarrow.c')
     for f in (maybe_nanoarrow_c, maybe_nanoarrow_h):
         if os.path.exists(f):
             os.unlink(f)
@@ -161,7 +161,7 @@ def copy_or_generate_nanoarrow_c():
             os.mkdir(build_dir)
             os.chdir(build_dir)
             os.system(f'cmake ../.. -DNANOARROW_BUNDLE=ON -DNANOARROW_NAMESPACE=PythonPkg')
-            os.system(f'cmake --install . --prefix=../nanoarrow')
+            os.system(f'cmake --install . --prefix=../src/nanoarrow')
         finally:
             if os.path.exists(build_dir):
                 # Can fail on Windows with permission issues
@@ -176,18 +176,18 @@ def copy_or_generate_nanoarrow_c():
     else:
         raise ValueError('Attempt to build source distribution outside the nanoarrow repo')
 
-    if not os.path.exists(os.path.join(this_dir, 'nanoarrow/nanoarrow.h')):
+    if not os.path.exists(os.path.join(this_dir, 'src/nanoarrow/nanoarrow.h')):
         raise ValueError('Attempt to vendor nanoarrow.c/h failed')
 
-    maybe_nanoarrow_hpp = os.path.join(this_dir, 'nanoarrow/nanoarrow.hpp')
+    maybe_nanoarrow_hpp = os.path.join(this_dir, 'src/nanoarrow/nanoarrow.hpp')
     if os.path.exists(maybe_nanoarrow_hpp):
         os.unlink(maybe_nanoarrow_hpp)
 
 # Runs the pxd generator with some information about the file name
 def generate_nanoarrow_pxd():
      this_dir = os.path.abspath(os.path.dirname(__file__))
-     maybe_nanoarrow_h = os.path.join(this_dir, 'nanoarrow/nanoarrow.h')
-     maybe_nanoarrow_pxd = os.path.join(this_dir, 'nanoarrow/nanoarrow_c.pxd')
+     maybe_nanoarrow_h = os.path.join(this_dir, 'src/nanoarrow/nanoarrow.h')
+     maybe_nanoarrow_pxd = os.path.join(this_dir, 'src/nanoarrow/nanoarrow_c.pxd')
 
      NanoarrowPxdGenerator().generate_nanoarrow_pxd(
         maybe_nanoarrow_h,

python/setup.py

@@ -45,11 +45,11 @@
     ext_modules=[
         Extension(
             name="nanoarrow._lib",
-            include_dirs=["nanoarrow"],
+            include_dirs=["src/nanoarrow"],
             language="c",
             sources=[
-                "nanoarrow/_lib.pyx",
-                "nanoarrow/nanoarrow.c",
+                "src/nanoarrow/_lib.pyx",
+                "src/nanoarrow/nanoarrow.c",
             ],
             extra_compile_args=coverage_compile_args,
             extra_link_args=coverage_link_args,