Merge PR432: improve servers of happiness integration test

The node creation helper used by the integration tests is now more careful about how it tweaks additional configuration file fields.  Previously, it could easily clobber certain settings.  Now it should only introduce the specific changes it intends.
Closes ticket:2895

integration/test_servers_of_happiness.py

@@ -1,10 +1,7 @@
 import sys
-import time
-import shutil
-from os import mkdir, unlink, listdir
-from os.path import join, exists
+from os.path import join
 
-from twisted.internet import defer, reactor, task
+from twisted.internet import task
 from twisted.internet.error import ProcessTerminated
 
 import util
@@ -15,13 +12,12 @@ import pytest
 @pytest.inlineCallbacks
 def test_upload_immutable(reactor, temp_dir, introducer_furl, flog_gatherer, storage_nodes, request):
 
-    # hmm, for some reason this still gets storage enabled ...
-    process = yield util._create_node(
+    yield util._create_node(
         reactor, request, temp_dir, introducer_furl, flog_gatherer, "edna",
         web_port="tcp:9983:interface=localhost",
         storage=False,
         needed=3,
-        happy=10,
+        happy=7,
         total=10,
     )
 
@@ -34,7 +30,7 @@ def test_upload_immutable(reactor, temp_dir, introducer_furl, flog_gatherer, sto
     # upload a file, which should fail because we have don't have 7
     # storage servers (but happiness is set to 7)
     proto = util._CollectOutputProtocol()
-    transport = reactor.spawnProcess(
+    reactor.spawnProcess(
         proto,
         sys.executable,
         [

integration/util.py

@@ -4,10 +4,16 @@ from os import mkdir
 from os.path import exists, join
 from StringIO import StringIO
 
-from twisted.internet.defer import Deferred
+from twisted.internet.defer import Deferred, succeed
 from twisted.internet.protocol import ProcessProtocol
 from twisted.internet.error import ProcessExitedAlready, ProcessDone
 
+from allmydata.util.configutil import (
+    get_config,
+    set_config,
+    write_config,
+)
+
 import pytest
 
 
@@ -145,7 +151,9 @@ def _create_node(reactor, request, temp_dir, introducer_furl, flog_gatherer, nam
     node_dir = join(temp_dir, name)
     if web_port is None:
         web_port = ''
-    if not exists(node_dir):
+    if exists(node_dir):
+        created_d = succeed(None)
+    else:
         print("creating", node_dir)
         mkdir(node_dir)
         done_proto = _ProcessExitedProtocol()
@@ -156,6 +164,10 @@ def _create_node(reactor, request, temp_dir, introducer_furl, flog_gatherer, nam
             '--introducer', introducer_furl,
             '--hostname', 'localhost',
             '--listen', 'tcp',
+            '--webport', web_port,
+            '--shares-needed', unicode(needed),
+            '--shares-happy', unicode(happy),
+            '--shares-total', unicode(total),
         ]
         if not storage:
             args.append('--no-storage')
@@ -169,33 +181,11 @@ def _create_node(reactor, request, temp_dir, introducer_furl, flog_gatherer, nam
         created_d = done_proto.done
 
         def created(_):
-            with open(join(node_dir, 'tahoe.cfg'), 'w') as f:
-                f.write('''
-[node]
-nickname = %(name)s
-web.port = %(web_port)s
-web.static = public_html
-log_gatherer.furl = %(log_furl)s
-
-[client]
-# Which services should this client connect to?
-introducer.furl = %(furl)s
-shares.needed = %(needed)d
-shares.happy = %(happy)d
-shares.total = %(total)d
-
-''' % {
-    'name': name,
-    'furl': introducer_furl,
-    'web_port': web_port,
-    'log_furl': flog_gatherer,
-    'needed': needed,
-    'happy': happy,
-    'total': total,
-})
+            config_path = join(node_dir, 'tahoe.cfg')
+            config = get_config(config_path)
+            set_config(config, 'node', 'log_gatherer.furl', flog_gatherer)
+            write_config(config_path, config)
         created_d.addCallback(created)
-    else:
-        created_d = defer.succeed(None)
 
     d = Deferred()
     d.callback(None)
@@ -234,5 +224,3 @@ def await_file_vanishes(path, timeout=10):
             return
         time.sleep(1)
     raise Exception("'{}' still exists after {}s".format(path, timeout))
-
-