Load plugins from outside the source tree.

So that plugins work with the packaged app on Windows and Mac.

PLUGINS.md

@@ -1,12 +1,18 @@
 # EDMC Plugins
 
-Market Connector Plugins allow you to customise and extend the behavior of EDMC. 
+Plugins allow you to customise and extend the behavior of EDMC.
 
 # Writing a Plugin
 
 Plugins are loaded when EDMC starts up.
 
-Plugins are python files. Each plugin has it's own folder in the `plugins` directory. The plugin must have a file named `load.py` that must provide one module level function and optionally provide a few others.
+Each plugin has it's own folder in the `plugins` directory:
+
+* Windows: `%LOCALAPPDATA%\EDMarketConnector\plugins`
+* Mac: `~/Library/Application Support/EDMarketConnector/plugins`
+* Linux: `$XDG_DATA_HOME/EDMarketConnector/plugins`, or `~/.local/share/EDMarketConnector/plugins` if `$XDG_DATA_HOME` is unset.
+
+Plugins are python files. The plugin folder must have a file named `load.py` that must provide one module level function and optionally provide a few others.
 
 EDMC will import the `load.py` file as a module and then call the `plugin_start()` function.
 

config.py

@@ -89,6 +89,10 @@ class Config:
             if not isdir(self.app_dir):
                 mkdir(self.app_dir)
 
+            self.plugin_dir = join(self.app_dir, 'plugins')
+            if not isdir(self.plugin_dir):
+                mkdir(self.plugin_dir)
+
             self.home = expanduser('~')
 
             if not getattr(sys, 'frozen', False):
@@ -131,6 +135,10 @@ class Config:
             if not isdir(self.app_dir):
                 mkdir(self.app_dir)
             
+            self.plugin_dir = join(self.app_dir, 'plugins')
+            if not isdir(self.plugin_dir):
+                mkdir(self.plugin_dir)
+
             # expanduser in Python 2 on Windows doesn't handle non-ASCII - http://bugs.python.org/issue13207
             ctypes.windll.shell32.SHGetSpecialFolderPathW(0, buf, CSIDL_PROFILE, 0)
             self.home = buf.value
@@ -206,6 +214,10 @@ class Config:
             if not isdir(self.app_dir):
                 makedirs(self.app_dir)
 
+            self.plugin_dir = join(self.app_dir, 'plugins')
+            if not isdir(self.plugin_dir):
+                mkdir(self.plugin_dir)
+
             self.home = expanduser('~')
 
             self.filename = join(getenv('XDG_CONFIG_HOME', expanduser('~/.config')), appname, '%s.ini' % appname)

plug.py

@@ -3,6 +3,9 @@ Plugin hooks for EDMC - Ian Norton
 """
 import os
 import imp
+import sys
+
+from config import config
 
 """
 Dictionary of loaded plugin modules.
@@ -16,9 +19,9 @@ def find_plugins():
     :return:
     """
     found = dict()
-    plug_folders = os.listdir("plugins")
+    plug_folders = os.listdir(config.plugin_dir)
     for name in plug_folders:
-        loadfile = os.path.join("plugins", name, "load.py")
+        loadfile = os.path.join(config.plugin_dir, name, "load.py")
         if os.path.isfile(loadfile):
             found[name] = loadfile
     return found
@@ -41,7 +44,7 @@ def load_plugins():
                     PLUGINS[plugname] = plugmod
 
         except Exception as plugerr:
-            print plugerr
+            sys.stderr.write('%s\n' % plugerr)	# appears in %TMP%/EDMarketConnector.log in packaged Windows app
 
     imp.release_lock()
 

plugins/About/load.py

@@ -1,6 +1,7 @@
 """
 A Skeleton EDMC Plugin
 """
+import sys
 import Tkinter as tk
 
 
@@ -9,7 +10,7 @@ def plugin_start():
     Start this plugin
     :return:
     """
-    print "example plugin started"
+    sys.stderr.write("example plugin started\n")	# appears in %TMP%/EDMarketConnector.log in packaged Windows app
 
 
 def plugin_prefs(parent):
@@ -46,7 +47,7 @@ def system_changed(timestamp, system):
     :param system: the name of the system
     :return:
     """
-    print "Arrived at {}".format(system)
+    sys.stderr.write("Arrived at {}\n".format(system))
 
 
 def cmdr_data(data):
@@ -56,7 +57,7 @@ def cmdr_data(data):
     :return:
     """
     cmdr_data.last = data
-    print "Got new data ({} chars)".format(len(str(data)))
+    sys.stderr.write("Got new data ({} chars)\n".format(len(str(data))))
 
 cmdr_data.last = None