Refactor mesh importer utility methods into public, second level API

CHANGELOG.md

@@ -11,6 +11,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+* Moved private methods `_get_file_format` and `_mesh_import` to `compas_robots.resources` and made them public (`get_file_format` and `mesh_import`). 
+
 ### Removed
 
 

src/compas_robots/resources/__init__.py

@@ -1,11 +1,15 @@
 from __future__ import absolute_import
 
+from .mesh_importer import get_file_format
+from .mesh_importer import mesh_import
 from .basic import AbstractMeshLoader
 from .basic import DefaultMeshLoader
 from .basic import LocalPackageMeshLoader
 from .github import GithubPackageMeshLoader
 
 __all__ = [
+    "get_file_format",
+    "mesh_import",
     "AbstractMeshLoader",
     "DefaultMeshLoader",
     "LocalPackageMeshLoader",

src/compas_robots/resources/basic.py

@@ -9,9 +9,8 @@
 except ImportError:
     from urlparse import urlparse
 
-from compas.datastructures import Mesh
-
-SUPPORTED_FORMATS = ("obj", "stl", "ply")
+from .mesh_importer import mesh_import
+from .mesh_importer import get_file_format
 
 
 class AbstractMeshLoader(object):
@@ -94,7 +93,7 @@ def can_load_mesh(self, url):
                 return True
 
         # Only OBJ loader supports remote files atm
-        is_obj = _get_file_format(url) == "obj"
+        is_obj = get_file_format(url) == "obj"
         return scheme in ("http", "https") and is_obj
 
     def load_meshes(self, url, precision=None):
@@ -115,7 +114,7 @@ def load_meshes(self, url, precision=None):
             List of meshes.
         """
         url = self._get_mesh_url(url)
-        return _mesh_import(url, url, precision)
+        return mesh_import(url, url, precision)
 
     def _get_mesh_url(self, url):
         """Concatenates basepath directory to URL only if defined in the keyword arguments.
@@ -141,14 +140,6 @@ def _get_mesh_url(self, url):
         return url
 
 
-def _get_file_format(url):
-    # This could be much more elaborate
-    # with an actual header check
-    # and/or remote content-type check
-    file_extension = url.split(".")[-1].lower()
-    return file_extension
-
-
 class LocalPackageMeshLoader(AbstractMeshLoader):
     """Loads suport package resources stored locally.
 
@@ -240,27 +231,8 @@ def load_meshes(self, url, precision=None):
             List of meshes.
         """
         local_file = self._get_local_path(url)
-        return _mesh_import(url, local_file, precision)
+        return mesh_import(url, local_file, precision)
 
     def _get_local_path(self, url):
         _prefix, path = url.split(self.schema_prefix)
         return self.build_path(*path.split("/"))
-
-
-def _mesh_import(name, file, precision=None):
-    """Internal function to load meshes using the correct loader.
-
-    Name and file might be the same but not always, e.g. temp files."""
-    file_extension = _get_file_format(name)
-
-    if file_extension not in SUPPORTED_FORMATS:
-        raise NotImplementedError("Mesh type not supported: {}".format(file_extension))
-
-    if file_extension == "obj":
-        return [Mesh.from_obj(file, precision)]
-    elif file_extension == "stl":
-        return [Mesh.from_stl(file, precision)]
-    elif file_extension == "ply":
-        return [Mesh.from_ply(file, precision)]
-
-    raise Exception

src/compas_robots/resources/github.py

@@ -8,7 +8,7 @@
     from urllib2 import urlopen
 
 from .basic import AbstractMeshLoader
-from .basic import _mesh_import
+from .mesh_importer import mesh_import
 
 
 class GithubPackageMeshLoader(AbstractMeshLoader):
@@ -112,4 +112,4 @@ def load_meshes(self, url, precision=None):
         _prefix, path = url.split(self.schema_prefix)
         url = self.build_url(path)
 
-        return _mesh_import(url, url, precision)
+        return mesh_import(url, url, precision)

src/compas_robots/resources/mesh_importer.py

@@ -0,0 +1,30 @@
+from compas.datastructures import Mesh
+
+SUPPORTED_FORMATS = ("obj", "stl", "ply")
+
+
+def get_file_format(url):
+    # This could be much more elaborate
+    # with an actual header check
+    # and/or remote content-type check
+    file_extension = url.split(".")[-1].lower()
+    return file_extension
+
+
+def mesh_import(name, file, precision=None):
+    """Internal function to load meshes using the correct loader.
+
+    Name and file might be the same but not always, e.g. temp files."""
+    file_extension = get_file_format(name)
+
+    if file_extension not in SUPPORTED_FORMATS:
+        raise NotImplementedError("Mesh type not supported: {}".format(file_extension))
+
+    if file_extension == "obj":
+        return [Mesh.from_obj(file, precision)]
+    elif file_extension == "stl":
+        return [Mesh.from_stl(file, precision)]
+    elif file_extension == "ply":
+        return [Mesh.from_ply(file, precision)]
+
+    raise Exception