Bring in the testrunner/http server scaffold for better integration testing.

This brings in a copy of llmessage's llsdmessage testing server.  We run
a mocked HTTP service to handle requests and the integration tests run
against it by picking up the LL_TEST_PORT environment variable when running.
Add some checks and output to produce useful info when run in the wrong
environment and when bad status is received.  Later will add a dead port
as well so we can test that rather than use 'localhost:2'.

1 files changed, 262 insertions, 0 deletions

diff --git a/indra/llcorehttp/tests/testrunner.py b/indra/llcorehttp/tests/testrunner.py
new file mode 100644
index 0000000000..f2c841532a
--- /dev/null
+++ b/indra/llcorehttp/tests/testrunner.py
@@ -0,0 +1,262 @@
+#!/usr/bin/env python
+"""\
+@file   testrunner.py
+@author Nat Goodspeed
+@date   2009-03-20
+@brief  Utilities for writing wrapper scripts for ADD_COMM_BUILD_TEST unit tests
+
+$LicenseInfo:firstyear=2009&license=viewerlgpl$
+Second Life Viewer Source Code
+Copyright (C) 2010, Linden Research, Inc.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation;
+version 2.1 of the License only.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+$/LicenseInfo$
+"""
+
+from __future__ import with_statement
+
+import os
+import sys
+import re
+import errno
+import socket
+
+VERBOSE = os.environ.get("INTEGRATION_TEST_VERBOSE", "1") # default to verbose
+# Support usage such as INTEGRATION_TEST_VERBOSE=off -- distressing to user if
+# that construct actually turns on verbosity...
+VERBOSE = not re.match(r"(0|off|false|quiet)$", VERBOSE, re.IGNORECASE)
+
+if VERBOSE:
+    def debug(fmt, *args):
+        print fmt % args
+        sys.stdout.flush()
+else:
+    debug = lambda *args: None
+
+def freeport(portlist, expr):
+    """
+    Find a free server port to use. Specifically, evaluate 'expr' (a
+    callable(port)) until it stops raising EADDRINUSE exception.
+
+    Pass:
+
+    portlist: an iterable (e.g. xrange()) of ports to try. If you exhaust the
+    range, freeport() lets the socket.error exception propagate. If you want
+    unbounded, you could pass itertools.count(baseport), though of course in
+    practice the ceiling is 2^16-1 anyway. But it seems prudent to constrain
+    the range much more sharply: if we're iterating an absurd number of times,
+    probably something else is wrong.
+
+    expr: a callable accepting a port number, specifically one of the items
+    from portlist. If calling that callable raises socket.error with
+    EADDRINUSE, freeport() retrieves the next item from portlist and retries.
+
+    Returns: (expr(port), port)
+
+    port: the value from portlist for which expr(port) succeeded
+
+    Raises:
+
+    Any exception raised by expr(port) other than EADDRINUSE.
+
+    socket.error if, for every item from portlist, expr(port) raises
+    socket.error. The exception you see is the one from the last item in
+    portlist.
+
+    StopIteration if portlist is completely empty.
+
+    Example:
+
+    class Server(HTTPServer):
+        # If you use BaseHTTPServer.HTTPServer, turning off this flag is
+        # essential for proper operation of freeport()!
+        allow_reuse_address = False
+    # ...
+    server, port = freeport(xrange(8000, 8010),
+                            lambda port: Server(("localhost", port),
+                                                MyRequestHandler))
+    # pass 'port' to client code
+    # call server.serve_forever()
+    """
+    try:
+        # If portlist is completely empty, let StopIteration propagate: that's an
+        # error because we can't return meaningful values. We have no 'port',
+        # therefore no 'expr(port)'.
+        portiter = iter(portlist)
+        port = portiter.next()
+
+        while True:
+            try:
+                # If this value of port works, return as promised.
+                value = expr(port)
+
+            except socket.error, err:
+                # Anything other than 'Address already in use', propagate
+                if err.args[0] != errno.EADDRINUSE:
+                    raise
+
+                # Here we want the next port from portiter. But on StopIteration,
+                # we want to raise the original exception rather than
+                # StopIteration. So save the original exc_info().
+                type, value, tb = sys.exc_info()
+                try:
+                    try:
+                        port = portiter.next()
+                    except StopIteration:
+                        raise type, value, tb
+                finally:
+                    # Clean up local traceback, see docs for sys.exc_info()
+                    del tb
+
+            else:
+                debug("freeport() returning %s on port %s", value, port)
+                return value, port
+
+            # Recap of the control flow above:
+            # If expr(port) doesn't raise, return as promised.
+            # If expr(port) raises anything but EADDRINUSE, propagate that
+            # exception.
+            # If portiter.next() raises StopIteration -- that is, if the port
+            # value we just passed to expr(port) was the last available -- reraise
+            # the EADDRINUSE exception.
+            # If we've actually arrived at this point, portiter.next() delivered a
+            # new port value. Loop back to pass that to expr(port).
+
+    except Exception, err:
+        debug("*** freeport() raising %s: %s", err.__class__.__name__, err)
+        raise
+
+def run(*args, **kwds):
+    """All positional arguments collectively form a command line, executed as
+    a synchronous child process.
+    In addition, pass server=new_thread_instance as an explicit keyword (to
+    differentiate it from an additional command-line argument).
+    new_thread_instance should be an instantiated but not yet started Thread
+    subclass instance, e.g.:
+    run("python", "-c", 'print "Hello, world!"', server=TestHTTPServer(name="httpd"))
+    """
+    # If there's no server= keyword arg, don't start a server thread: simply
+    # run a child process.
+    try:
+        thread = kwds.pop("server")
+    except KeyError:
+        pass
+    else:
+        # Start server thread. Note that this and all other comm server
+        # threads should be daemon threads: we'll let them run "forever,"
+        # confident that the whole process will terminate when the main thread
+        # terminates, which will be when the child process terminates.
+        thread.setDaemon(True)
+        thread.start()
+    # choice of os.spawnv():
+    # - [v vs. l] pass a list of args vs. individual arguments,
+    # - [no p] don't use the PATH because we specifically want to invoke the
+    #   executable passed as our first arg,
+    # - [no e] child should inherit this process's environment.
+    debug("Running %s...", " ".join(args))
+    rc = os.spawnv(os.P_WAIT, args[0], args)
+    debug("%s returned %s", args[0], rc)
+    return rc
+
+# ****************************************************************************
+#   test code -- manual at this point, see SWAT-564
+# ****************************************************************************
+def test_freeport():
+    # ------------------------------- Helpers --------------------------------
+    from contextlib import contextmanager
+    # helper Context Manager for expecting an exception
+    # with exc(SomeError):
+    #     raise SomeError()
+    # raises AssertionError otherwise.
+    @contextmanager
+    def exc(exception_class, *args):
+        try:
+            yield
+        except exception_class, err:
+            for i, expected_arg in enumerate(args):
+                assert expected_arg == err.args[i], \
+                       "Raised %s, but args[%s] is %r instead of %r" % \
+                       (err.__class__.__name__, i, err.args[i], expected_arg)
+            print "Caught expected exception %s(%s)" % \
+                  (err.__class__.__name__, ', '.join(repr(arg) for arg in err.args))
+        else:
+            assert False, "Failed to raise " + exception_class.__class__.__name__
+
+    # helper to raise specified exception
+    def raiser(exception):
+        raise exception
+
+    # the usual
+    def assert_equals(a, b):
+        assert a == b, "%r != %r" % (a, b)
+
+    # ------------------------ Sanity check the above ------------------------
+    class SomeError(Exception): pass
+    # Without extra args, accept any err.args value
+    with exc(SomeError):
+        raiser(SomeError("abc"))
+    # With extra args, accept only the specified value
+    with exc(SomeError, "abc"):
+        raiser(SomeError("abc"))
+    with exc(AssertionError):
+        with exc(SomeError, "abc"):
+            raiser(SomeError("def"))
+    with exc(AssertionError):
+        with exc(socket.error, errno.EADDRINUSE):
+            raiser(socket.error(errno.ECONNREFUSED, 'Connection refused'))
+
+    # ----------- freeport() without engaging socket functionality -----------
+    # If portlist is empty, freeport() raises StopIteration.
+    with exc(StopIteration):
+        freeport([], None)
+
+    assert_equals(freeport([17], str), ("17", 17))
+
+    # This is the magic exception that should prompt us to retry
+    inuse = socket.error(errno.EADDRINUSE, 'Address already in use')
+    # Get the iterator to our ports list so we can check later if we've used all
+    ports = iter(xrange(5))
+    with exc(socket.error, errno.EADDRINUSE):
+        freeport(ports, lambda port: raiser(inuse))
+    # did we entirely exhaust 'ports'?
+    with exc(StopIteration):
+        ports.next()
+
+    ports = iter(xrange(2))
+    # Any exception but EADDRINUSE should quit immediately
+    with exc(SomeError):
+        freeport(ports, lambda port: raiser(SomeError()))
+    assert_equals(ports.next(), 1)
+
+    # ----------- freeport() with platform-dependent socket stuff ------------
+    # This is what we should've had unit tests to begin with (see CHOP-661).
+    def newbind(port):
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock.bind(('127.0.0.1', port))
+        return sock
+
+    bound0, port0 = freeport(xrange(7777, 7780), newbind)
+    assert_equals(port0, 7777)
+    bound1, port1 = freeport(xrange(7777, 7780), newbind)
+    assert_equals(port1, 7778)
+    bound2, port2 = freeport(xrange(7777, 7780), newbind)
+    assert_equals(port2, 7779)
+    with exc(socket.error, errno.EADDRINUSE):
+        bound3, port3 = freeport(xrange(7777, 7780), newbind)
+
+if __name__ == "__main__":
+    test_freeport()