New migration import mechanics, borrowed from market conversion imports, because we can't os.listdir from a zipfile

eos/db/migration.py

@@ -3,17 +3,7 @@ import shutil
 import time
 import re
 import os
-
-def getAppVersion():
-    # calculate app version based on upgrade files we have
-    appVersion = 0
-    for fname in os.listdir(os.path.join(os.path.dirname(__file__), "migrations")):
-        m = re.match("^upgrade(?P<index>\d+)\.py$", fname)
-        if not m:
-            continue
-        index = int(m.group("index"))
-        appVersion = max(appVersion, index)
-    return appVersion
+import migrations
 
 def getVersion(db):
     cursor = db.execute('PRAGMA user_version')
@@ -21,7 +11,9 @@ def getVersion(db):
 
 def update(saveddata_engine):
     dbVersion = getVersion(saveddata_engine)
-    appVersion = getAppVersion()
+    appVersion = migrations.appVersion
+
+    print dbVersion, appVersion
 
     if dbVersion == appVersion:
         return
@@ -37,10 +29,11 @@ def update(saveddata_engine):
         shutil.copyfile(config.saveDB, toFile)
 
         for version in xrange(dbVersion, appVersion):
-            module = __import__("eos.db.migrations.upgrade{}".format(version + 1), fromlist=True)
-            upgrade = getattr(module, "upgrade", False)
-            if upgrade:
-                upgrade(saveddata_engine)
+
+            func = migrations.updates[version+1]
+            if func:
+                print "applying update",version+1
+                func(saveddata_engine)
 
         # when all is said and done, set version to current
         saveddata_engine.execute("PRAGMA user_version = {}".format(appVersion))

eos/db/migrations/__init__.py

@@ -7,3 +7,25 @@ define an upgrade() function with the logic. Please note that there must be as
 many upgrade files as there are database versions (version 5 would include
 upgrade files 1-5)
 """
+
+import pkgutil
+import re
+
+
+updates = {}
+appVersion = 0
+
+prefix = __name__ + "."
+for importer, modname, ispkg in pkgutil.iter_modules(__path__, prefix):
+    # loop through python files, extracting update number and function, and
+    # adding it to a list
+    modname_tail = modname.rsplit('.', 1)[-1]
+    module = __import__(modname, fromlist=True)
+    m = re.match("^upgrade(?P<index>\d+)$", modname_tail)
+    if not m:
+        continue
+    index = int(m.group("index"))
+    appVersion = max(appVersion, index)
+    upgrade = getattr(module, "upgrade", False)
+    if upgrade:
+        updates[index] = upgrade