Add test for WSGI server, and fix a str/bytes bug that it found

nilmdb/server/server.py

@@ -501,7 +501,7 @@ class Server(object):
 # work, the web server must use only a single process and single
 # Python interpreter.  Multiple threads are OK.
 _wsgi_server = None
-def wsgi_application(dbpath, basepath): # pragma: no cover
+def wsgi_application(dbpath, basepath):
     """Return a WSGI application object with a database at the
     specified path.
 
@@ -526,23 +526,21 @@ def wsgi_application(dbpath, basepath): # pragma: no cover
                 err = sprintf("Initializing database at path '%s' failed:\n\n",
                               dbpath)
                 err += traceback.format_exc()
-                try:
-                    import pwd
-                    import grp
-                    err += sprintf("\nRunning as: uid=%d (%s), gid=%d (%s) "
-                                   "on host %s, pid %d\n",
-                                   os.getuid(), pwd.getpwuid(os.getuid())[0],
-                                   os.getgid(), grp.getgrgid(os.getgid())[0],
-                                   socket.gethostname(), os.getpid())
-                except ImportError:
-                    pass
+                import pwd
+                import grp
+                err += sprintf("\nRunning as: uid=%d (%s), gid=%d (%s) "
+                               "on host %s, pid %d\n",
+                               os.getuid(), pwd.getpwuid(os.getuid())[0],
+                               os.getgid(), grp.getgrgid(os.getgid())[0],
+                               socket.gethostname(), os.getpid())
                 err += sprintf("\nEnvironment:\n%s\n", pprint.pformat(environ))
         if _wsgi_server is None:
             # Serve up the error with our own mini WSGI app.
-            headers = [ ('Content-type', 'text/plain'),
-                        ('Content-length', str(len(err))) ]
+            err_b = err.encode('utf-8')
+            headers = [ ('Content-type', 'text/plain; charset=utf-8'),
+                        ('Content-length', str(len(err_b))) ]
             start_response("500 Internal Server Error", headers)
-            return [err]
+            return [err_b]
 
         # Call the normal application
         return _wsgi_server.wsgi_application(environ, start_response)

requirements.txt

@@ -1,6 +1,6 @@
-cython>=0.29.13
 CherryPy>=18.1.2
 coverage>=4.5.4
+cython>=0.29.13
 decorator>=4.4.0
 fallocate>=1.6.4
 nose>=1.3.7
@@ -11,3 +11,4 @@ python-datetime-tz>=0.5.4
 python-dateutil>=2.8.0
 requests>=2.22.0
 tz>=0.2.2
+WebTest>=2.0.33

tests/test.order

@@ -12,6 +12,7 @@ test_interval.py
 
 test_bulkdata.py
 test_nilmdb.py
+test_wsgi.py
 test_client.py
 test_numpyclient.py
 test_cmdline.py

tests/test_wsgi.py

@@ -0,0 +1,36 @@
+from nose.tools import *
+from nose.tools import assert_raises
+from testutil.helpers import *
+
+import io
+import os
+import sys
+import time
+
+import nilmdb.server
+import webtest
+
+testdb = "tests/testdb"
+
+# Test WSGI interface
+
+class TestWSGI(object):
+    def test_wsgi(self):
+
+        # Bad database gives debug info
+        app = webtest.TestApp(nilmdb.server.wsgi_application("/dev/null", "/"))
+        resp = app.get('/', expect_errors=True)
+        eq_(resp.status_int, 500)
+        eq_(resp.content_type, "text/plain")
+        body = resp.body.decode('utf-8')
+        in_("Initializing database at path '/dev/null' failed", body)
+        in_("Not a directory: b'/dev/null/data'", body)
+        in_("Running as: uid=", body)
+        in_("Environment:", body)
+
+        # Good database works fine
+        app = webtest.TestApp(nilmdb.server.wsgi_application(testdb, "/nilmdb"))
+        resp = app.get('/version', expect_errors=True)
+        eq_(resp.status_int, 404)
+        resp = app.get('/nilmdb/version')
+        eq_(resp.json, nilmdb.__version__)