Merge pull request #909 from compas-dev/artist-factory-plugins

Artist factory plugins

Author: gonzalocasas

docs/devguide.rst

@@ -390,10 +390,12 @@ Advanced options
 
 There are a few additional options that plugins can use:
 
-* ``requires``: List of required python modules. COMPAS will filter out plugins if their
+* ``requires``: List of requirements. COMPAS will filter out plugins if their
   requirements list is not satisfied at runtime. This allows to have multiple implementations
-  of the same operation and have them selected based on which packages are installed.
-  on the system. Eg. `requires=['scipy']`.
+  of the same operation and have them selected based on different criteria.
+  The requirement can either be a package name string (e.g. ``requires=['scipy']``) or
+  a ``callable`` with a boolean return value, in which any arbitrary check can be implemented
+  (e.g. ``requires=[lambda: is_rhino_active()]``).
 * ``tryfirst`` and ``trylast``: Plugins cannot control the exact priority they will have
   but they can indicate whether to try to prioritize them or demote them as fallback using
   these two boolean parameters.

src/compas/plugins.py

@@ -321,9 +321,11 @@ def plugin(method=None, category=None, requires=None, tryfirst=False, trylast=Fa
         The method to decorate as ``plugin``.
     category : str, optional
         An optional string to group or categorize plugins.
-    requires : list of str, optional
-        Optionally defines a list of packages that should be importable
-        for this plugin to be used.
+    requires : list, optional
+        Optionally defines a list of requirements that should be fulfilled
+        for this plugin to be used. The requirement can either be a package
+        name (``str``) or a ``callable`` with a boolean return value,
+        in which any arbitrary check can be implemented.
     tryfirst : bool, optional
         Plugins can declare a preferred priority by setting this to ``True``.
         By default ``False``.
@@ -414,9 +416,16 @@ def check_importable(self, module_name):
         return self._cache[module_name]
 
 
+def verify_requirement(manager, requirement):
+    if callable(requirement):
+        return requirement()
+
+    return manager.importer.check_importable(requirement)
+
+
 def is_plugin_selectable(plugin, manager):
     if plugin.opts['requires']:
-        importable_requirements = (manager.importer.check_importable(name) for name in plugin.opts['requires'])
+        importable_requirements = (verify_requirement(manager, requirement) for requirement in plugin.opts['requires'])
 
         if not all(importable_requirements):
             if manager.DEBUG:

src/compas_ghpython/__init__.py

@@ -69,5 +69,9 @@ def _get_grasshopper_special_folder(version, folder_name):
     return grasshopper_library_path
 
 
-__all_plugins__ = ['compas_ghpython.install', 'compas_ghpython.uninstall']
+__all_plugins__ = [
+    'compas_ghpython.install',
+    'compas_ghpython.uninstall',
+    'compas_ghpython.artists',
+]
 __all__ = [name for name in dir() if not name.startswith('_')]

src/compas_ghpython/artists/__init__.py

@@ -71,6 +71,8 @@
 from compas.datastructures import Network
 from compas.datastructures import VolMesh
 
+from compas.robots import RobotModel
+
 from .artist import GHArtist
 from .circleartist import CircleArtist
 from .frameartist import FrameArtist
@@ -99,7 +101,17 @@
 VolMeshArtist.default_cellcolor = (255, 0, 0)
 
 
-@plugin(category='factories', pluggable_name='new_artist', requires=['ghpythonlib'])
+def verify_gh_context():
+    try:
+        import Rhino
+        import scriptcontext as sc
+
+        return not isinstance(sc.doc, Rhino.RhinoDoc)
+    except:
+        return False
+
+
+@plugin(category='factories', pluggable_name='new_artist', requires=['ghpythonlib', verify_gh_context])
 def new_artist_gh(cls, *args, **kwargs):
     # "lazy registration" seems necessary to avoid item-artist pairs to be overwritten unintentionally
 
@@ -111,6 +123,7 @@ def new_artist_gh(cls, *args, **kwargs):
     GHArtist.register(Mesh, MeshArtist)
     GHArtist.register(Network, NetworkArtist)
     GHArtist.register(VolMesh, VolMeshArtist)
+    GHArtist.register(RobotModel, RobotModelArtist)
 
     data = args[0]
 
@@ -127,7 +140,7 @@ def new_artist_gh(cls, *args, **kwargs):
     for name, value in inspect.getmembers(cls):
         if inspect.ismethod(value):
             if hasattr(value, '__isabstractmethod__'):
-                raise Exception('Abstract method not implemented')
+                raise Exception('Abstract method not implemented: {}'.format(value))
 
     return super(Artist, cls).__new__(cls)
 

src/compas_rhino/artists/__init__.py

@@ -141,7 +141,17 @@
 VolMeshArtist.default_cellcolor = (255, 0, 0)
 
 
-@plugin(category='factories', pluggable_name='new_artist', requires=['Rhino'])
+def verify_rhino_context():
+    try:
+        import Rhino
+        import scriptcontext as sc
+
+        return isinstance(sc.doc, Rhino.RhinoDoc)
+    except:
+        return False
+
+
+@plugin(category='factories', pluggable_name='new_artist', requires=['Rhino', verify_rhino_context])
 def new_artist_rhino(cls, *args, **kwargs):
     # "lazy registration" seems necessary to avoid item-artist pairs to be overwritten unintentionally
 
@@ -180,7 +190,7 @@ def new_artist_rhino(cls, *args, **kwargs):
     for name, value in inspect.getmembers(cls):
         if inspect.ismethod(value):
             if hasattr(value, '__isabstractmethod__'):
-                raise Exception('Abstract method not implemented')
+                raise Exception('Abstract method not implemented: {}'.format(value))
 
     return super(Artist, cls).__new__(cls)