Implement simpler Mesa namespace

Author: rht

.coveragerc

@@ -5,3 +5,4 @@ branch = True
 [report]
 omit =
     tests/*
+    mesa/flat/*

examples/wolf_sheep/wolf_sheep/agents.py

@@ -1,4 +1,4 @@
-from mesa import Agent
+import mesa
 from wolf_sheep.random_walk import RandomWalker
 
 
@@ -92,7 +92,7 @@ def step(self):
                 self.model.schedule.add(cub)
 
 
-class GrassPatch(Agent):
+class GrassPatch(mesa.Agent):
     """
     A patch of grass that grows at a fixed rate and it is eaten by sheep
     """

examples/wolf_sheep/wolf_sheep/model.py

@@ -9,15 +9,13 @@
     Northwestern University, Evanston, IL.
 """
 
-from mesa import Model
-from mesa.space import MultiGrid
-from mesa.datacollection import DataCollector
+import mesa
 
 from wolf_sheep.scheduler import RandomActivationByTypeFiltered
 from wolf_sheep.agents import Sheep, Wolf, GrassPatch
 
 
-class WolfSheep(Model):
+class WolfSheep(mesa.Model):
     """
     Wolf-Sheep Predation Model
     """
@@ -84,8 +82,8 @@ def __init__(
         self.sheep_gain_from_food = sheep_gain_from_food
 
         self.schedule = RandomActivationByTypeFiltered(self)
-        self.grid = MultiGrid(self.width, self.height, torus=True)
-        self.datacollector = DataCollector(
+        self.grid = mesa.space.MultiGrid(self.width, self.height, torus=True)
+        self.datacollector = mesa.DataCollector(
             {
                 "Wolves": lambda m: m.schedule.get_type_count(Wolf),
                 "Sheep": lambda m: m.schedule.get_type_count(Sheep),

examples/wolf_sheep/wolf_sheep/server.py

@@ -1,6 +1,4 @@
-from mesa.visualization.ModularVisualization import ModularServer
-from mesa.visualization.modules import CanvasGrid, ChartModule
-from mesa.visualization.UserParam import UserSettableParameter
+import mesa
 
 from wolf_sheep.agents import Wolf, Sheep, GrassPatch
 from wolf_sheep.model import WolfSheep
@@ -40,8 +38,8 @@ def wolf_sheep_portrayal(agent):
     return portrayal
 
 
-canvas_element = CanvasGrid(wolf_sheep_portrayal, 20, 20, 500, 500)
-chart_element = ChartModule(
+canvas_element = mesa.visualization.CanvasGrid(wolf_sheep_portrayal, 20, 20, 500, 500)
+chart_element = mesa.visualization.ChartModule(
     [
         {"Label": "Wolves", "Color": "#AA0000"},
         {"Label": "Sheep", "Color": "#666666"},
@@ -50,20 +48,22 @@ def wolf_sheep_portrayal(agent):
 )
 
 model_params = {
-    "grass": UserSettableParameter("checkbox", "Grass Enabled", True),
-    "grass_regrowth_time": UserSettableParameter(
+    "grass": mesa.visualization.UserSettableParameter(
+        "checkbox", "Grass Enabled", True
+    ),
+    "grass_regrowth_time": mesa.visualization.UserSettableParameter(
         "slider", "Grass Regrowth Time", 20, 1, 50
     ),
-    "initial_sheep": UserSettableParameter(
+    "initial_sheep": mesa.visualization.UserSettableParameter(
         "slider", "Initial Sheep Population", 100, 10, 300
     ),
-    "sheep_reproduce": UserSettableParameter(
+    "sheep_reproduce": mesa.visualization.UserSettableParameter(
         "slider", "Sheep Reproduction Rate", 0.04, 0.01, 1.0, 0.01
     ),
-    "initial_wolves": UserSettableParameter(
+    "initial_wolves": mesa.visualization.UserSettableParameter(
         "slider", "Initial Wolf Population", 50, 10, 300
     ),
-    "wolf_reproduce": UserSettableParameter(
+    "wolf_reproduce": mesa.visualization.UserSettableParameter(
         "slider",
         "Wolf Reproduction Rate",
         0.05,
@@ -72,15 +72,15 @@ def wolf_sheep_portrayal(agent):
         0.01,
         description="The rate at which wolf agents reproduce.",
     ),
-    "wolf_gain_from_food": UserSettableParameter(
+    "wolf_gain_from_food": mesa.visualization.UserSettableParameter(
         "slider", "Wolf Gain From Food Rate", 20, 1, 50
     ),
-    "sheep_gain_from_food": UserSettableParameter(
+    "sheep_gain_from_food": mesa.visualization.UserSettableParameter(
         "slider", "Sheep Gain From Food", 4, 1, 10
     ),
 }
 
-server = ModularServer(
+server = mesa.visualization.ModularServer(
     WolfSheep, [canvas_element, chart_element], "Wolf Sheep Predation", model_params
 )
 server.port = 8521

mesa/__init__.py

@@ -9,8 +9,12 @@
 from mesa.model import Model
 from mesa.agent import Agent
 
+import mesa.time as time
+import mesa.space as space
+import mesa.flat.visualization as visualization
+from mesa.datacollection import DataCollector
 
-__all__ = ["Model", "Agent"]
+__all__ = ["Model", "Agent", "time", "space", "visualization", "DataCollector"]
 
 __title__ = "mesa"
 __version__ = "0.9.0"

mesa/flat/__init__.py

@@ -0,0 +1,5 @@
+from mesa import *  # noqa
+from mesa.time import *  # noqa
+from mesa.space import *  # noqa
+from mesa.datacollection import *  # noqa
+from .visualization import *  # noqa

mesa/flat/visualization.py

@@ -0,0 +1,4 @@
+# This collects all of Mesa visualization components under a flat namespace.
+from mesa.visualization.ModularVisualization import *  # noqa
+from mesa.visualization.modules import *  # noqa
+from mesa.visualization.UserParam import *  # noqa

tests/test_import_namespace.py

@@ -0,0 +1,29 @@
+def test_import():
+    # This tests the new, simpler Mesa namespace. See
+    # https://github.com/projectmesa/mesa/pull/1294.
+    import mesa
+    import mesa.flat as mf
+
+    from mesa.time import RandomActivation
+
+    mesa.time.RandomActivation
+    RandomActivation
+    mf.RandomActivation
+
+    from mesa.space import MultiGrid
+
+    mesa.space.MultiGrid
+    MultiGrid
+    mf.MultiGrid
+
+    from mesa.visualization.ModularVisualization import ModularServer
+
+    mesa.visualization.ModularServer
+    ModularServer
+    mf.ModularServer
+
+    from mesa.datacollection import DataCollector
+
+    DataCollector
+    mesa.DataCollector
+    mf.DataCollector

tests/test_main.py

@@ -20,9 +20,7 @@ def tearDown(self):
         sys.path[:] = self.old_sys_path
 
     def test_run(self):
-        with patch(
-            "mesa.visualization.ModularVisualization.ModularServer"
-        ) as ModularServer:
+        with patch("mesa.visualization.ModularServer") as ModularServer:
             example_dir = os.path.abspath(
                 os.path.join(os.path.dirname(__file__), "../examples/wolf_sheep")
             )