Adding --port option to pubsub.py client (take 2) (#195)

- Added `--port` option to be able to set the port when connecting with MQTT/TLS
- Builder now uses default values if any arg is `None`. Previously, omitting an arg was the only way to get defaults.
- Builder properly sets ALPN string if user passes in port=443

Author: graebm

awsiot/mqtt_connection_builder.py

@@ -11,7 +11,7 @@
     **client_id** (`str`): ID to place in CONNECT packet. Must be unique across all devices/clients.
             If an ID is already in use, the other client will be disconnected.
 
-Optional Keyword Arguments:
+Optional Keyword Arguments (omit, or set `None` to get default value):
 
     **on_connection_interrupted** (`Callable`): Callback invoked whenever the MQTT connection is lost.
         The MQTT client will automatically attempt to reconnect.
@@ -106,6 +106,20 @@ def _check_required_kwargs(**kwargs):
             raise TypeError("Builder needs keyword-only argument '{}'".format(required))
 
 
+def _get(kwargs, name, default=None):
+    """
+    Returns kwargs['name'] if it exists and is not None.
+    Otherwise returns default.
+
+    This function exists so users can pass some_arg=None to get its default
+    value, instead of literally passing None.
+    """
+    val = kwargs.get(name)
+    if val is None:
+        val = default
+    return val
+
+
 _metrics_str = None
 
 
@@ -132,64 +146,64 @@ def _builder(
         websocket_proxy_options=None,
         **kwargs):
 
-    ca_bytes = kwargs.get('ca_bytes')
-    ca_filepath = kwargs.get('ca_filepath')
-    ca_dirpath = kwargs.get('ca_dirpath')
+    ca_bytes = _get(kwargs, 'ca_bytes')
+    ca_filepath = _get(kwargs, 'ca_filepath')
+    ca_dirpath = _get(kwargs, 'ca_dirpath')
     if ca_bytes:
         tls_ctx_options.override_default_trust_store(ca_bytes)
     elif ca_filepath or ca_dirpath:
         tls_ctx_options.override_default_trust_store_from_path(ca_dirpath, ca_filepath)
 
-    if use_websockets:
-        port = 443
-        if awscrt.io.is_alpn_available():
-            tls_ctx_options.alpn_list = ['http/1.1']
-    else:
-        port = 8883
-        if awscrt.io.is_alpn_available():
+    port = _get(kwargs, 'port')
+    if port is None:
+        # prefer 443, even for direct MQTT connections, since it's less likely to be blocked by firewalls
+        if use_websockets or awscrt.io.is_alpn_available():
             port = 443
-            tls_ctx_options.alpn_list = ['x-amzn-mqtt-ca']
+        else:
+            port = 8883
 
-    port = kwargs.get('port', port)
+    if port == 443 and awscrt.io.is_alpn_available():
+        tls_ctx_options.alpn_list = ['http/1.1'] if use_websockets else ['x-amzn-mqtt-ca']
 
     socket_options = awscrt.io.SocketOptions()
-    socket_options.connect_timeout_ms = kwargs.get('tcp_connect_timeout_ms', 5000)
+    socket_options.connect_timeout_ms = _get(kwargs, 'tcp_connect_timeout_ms', 5000)
     # These have been inconsistent between keepalive/keep_alive. Resolve both for now to ease transition.
-    socket_options.keep_alive = kwargs.get('tcp_keep_alive', kwargs.get('tcp_keepalive', False))
-    socket_options.keep_alive_timeout_secs = kwargs.get(
-        'tcp_keep_alive_timeout_secs', kwargs.get(
-            'tcp_keepalive_timeout_secs', 0))
-    socket_options.keep_alive_interval_secs = kwargs.get(
-        'tcp_keep_alive_interval_secs', kwargs.get(
-            'tcp_keepalive_interval_secs', 0))
-    socket_options.keep_alive_max_probes = kwargs.get(
-        'tcp_keep_alive_max_probes', kwargs.get(
-            'tcp_keepalive_max_probes', 0))
-
-    username = kwargs.get('username', '')
-    if kwargs.get('enable_metrics_collection', True):
+    socket_options.keep_alive = \
+        _get(kwargs, 'tcp_keep_alive', _get(kwargs, 'tcp_keepalive', False))
+
+    socket_options.keep_alive_timeout_secs = \
+        _get(kwargs, 'tcp_keep_alive_timeout_secs', _get(kwargs, 'tcp_keepalive_timeout_secs', 0))
+
+    socket_options.keep_alive_interval_secs = \
+        _get(kwargs, 'tcp_keep_alive_interval_secs', _get(kwargs, 'tcp_keepalive_interval_secs', 0))
+
+    socket_options.keep_alive_max_probes = \
+        _get(kwargs, 'tcp_keep_alive_max_probes', _get(kwargs, 'tcp_keepalive_max_probes', 0))
+
+    username = _get(kwargs, 'username', '')
+    if _get(kwargs, 'enable_metrics_collection', True):
         username += _get_metrics_str()
 
-    client_bootstrap = kwargs.get('client_bootstrap')
+    client_bootstrap = _get(kwargs, 'client_bootstrap')
     tls_ctx = awscrt.io.ClientTlsContext(tls_ctx_options)
     mqtt_client = awscrt.mqtt.Client(client_bootstrap, tls_ctx)
 
     return awscrt.mqtt.Connection(
         client=mqtt_client,
-        on_connection_interrupted=kwargs.get('on_connection_interrupted'),
-        on_connection_resumed=kwargs.get('on_connection_resumed'),
-        client_id=kwargs.get('client_id'),
-        host_name=kwargs.get('endpoint'),
+        on_connection_interrupted=_get(kwargs, 'on_connection_interrupted'),
+        on_connection_resumed=_get(kwargs, 'on_connection_resumed'),
+        client_id=_get(kwargs, 'client_id'),
+        host_name=_get(kwargs, 'endpoint'),
         port=port,
-        clean_session=kwargs.get('clean_session', False),
-        reconnect_min_timeout_secs=kwargs.get('reconnect_min_timeout_secs', 5),
-        reconnect_max_timeout_secs=kwargs.get('reconnect_max_timeout_secs', 60),
-        keep_alive_secs=kwargs.get('keep_alive_secs', 1200),
-        ping_timeout_ms=kwargs.get('ping_timeout_ms', 3000),
-        protocol_operation_timeout_ms=kwargs.get('protocol_operation_timeout_ms', 0),
-        will=kwargs.get('will'),
+        clean_session=_get(kwargs, 'clean_session', False),
+        reconnect_min_timeout_secs=_get(kwargs, 'reconnect_min_timeout_secs', 5),
+        reconnect_max_timeout_secs=_get(kwargs, 'reconnect_max_timeout_secs', 60),
+        keep_alive_secs=_get(kwargs, 'keep_alive_secs', 1200),
+        ping_timeout_ms=_get(kwargs, 'ping_timeout_ms', 3000),
+        protocol_operation_timeout_ms=_get(kwargs, 'protocol_operation_timeout_ms', 0),
+        will=_get(kwargs, 'will'),
         username=username,
-        password=kwargs.get('password'),
+        password=_get(kwargs, 'password'),
         socket_options=socket_options,
         use_websockets=use_websockets,
         websocket_handshake_transform=websocket_handshake_transform,

docs/_static/basic.css

@@ -130,7 +130,7 @@ ul.search li a {
     font-weight: bold;
 }
 
-ul.search li div.context {
+ul.search li p.context {
     color: #888;
     margin: 2px 0 0 30px;
     text-align: left;
@@ -277,25 +277,25 @@ p.rubric {
     font-weight: bold;
 }
 
-img.align-left, .figure.align-left, object.align-left {
+img.align-left, figure.align-left, .figure.align-left, object.align-left {
     clear: left;
     float: left;
     margin-right: 1em;
 }
 
-img.align-right, .figure.align-right, object.align-right {
+img.align-right, figure.align-right, .figure.align-right, object.align-right {
     clear: right;
     float: right;
     margin-left: 1em;
 }
 
-img.align-center, .figure.align-center, object.align-center {
+img.align-center, figure.align-center, .figure.align-center, object.align-center {
   display: block;
   margin-left: auto;
   margin-right: auto;
 }
 
-img.align-default, .figure.align-default {
+img.align-default, figure.align-default, .figure.align-default {
   display: block;
   margin-left: auto;
   margin-right: auto;
@@ -319,7 +319,8 @@ img.align-default, .figure.align-default {
 
 /* -- sidebars -------------------------------------------------------------- */
 
-div.sidebar {
+div.sidebar,
+aside.sidebar {
     margin: 0 0 0.5em 1em;
     border: 1px solid #ddb;
     padding: 7px;
@@ -377,12 +378,14 @@ div.body p.centered {
 /* -- content of sidebars/topics/admonitions -------------------------------- */
 
 div.sidebar > :last-child,
+aside.sidebar > :last-child,
 div.topic > :last-child,
 div.admonition > :last-child {
     margin-bottom: 0;
 }
 
 div.sidebar::after,
+aside.sidebar::after,
 div.topic::after,
 div.admonition::after,
 blockquote::after {
@@ -455,20 +458,22 @@ td > :last-child {
 
 /* -- figures --------------------------------------------------------------- */
 
-div.figure {
+div.figure, figure {
     margin: 0.5em;
     padding: 0.5em;
 }
 
-div.figure p.caption {
+div.figure p.caption, figcaption {
     padding: 0.3em;
 }
 
-div.figure p.caption span.caption-number {
+div.figure p.caption span.caption-number,
+figcaption span.caption-number {
     font-style: italic;
 }
 
-div.figure p.caption span.caption-text {
+div.figure p.caption span.caption-text,
+figcaption span.caption-text {
 }
 
 /* -- field list styles ----------------------------------------------------- */
@@ -503,6 +508,63 @@ table.hlist td {
     vertical-align: top;
 }
 
+/* -- object description styles --------------------------------------------- */
+
+.sig {
+	font-family: 'Consolas', 'Menlo', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', monospace;
+}
+
+.sig-name, code.descname {
+    background-color: transparent;
+    font-weight: bold;
+}
+
+.sig-name {
+	font-size: 1.1em;
+}
+
+code.descname {
+    font-size: 1.2em;
+}
+
+.sig-prename, code.descclassname {
+    background-color: transparent;
+}
+
+.optional {
+    font-size: 1.3em;
+}
+
+.sig-paren {
+    font-size: larger;
+}
+
+.sig-param.n {
+	font-style: italic;
+}
+
+/* C++ specific styling */
+
+.sig-inline.c-texpr,
+.sig-inline.cpp-texpr {
+	font-family: unset;
+}
+
+.sig.c   .k, .sig.c   .kt,
+.sig.cpp .k, .sig.cpp .kt {
+	color: #0033B3;
+}
+
+.sig.c   .m,
+.sig.cpp .m {
+	color: #1750EB;
+}
+
+.sig.c   .s, .sig.c   .sc,
+.sig.cpp .s, .sig.cpp .sc {
+	color: #067D17;
+}
+
 
 /* -- other body styles ----------------------------------------------------- */
 
@@ -629,14 +691,6 @@ dl.glossary dt {
     font-size: 1.1em;
 }
 
-.optional {
-    font-size: 1.3em;
-}
-
-.sig-paren {
-    font-size: larger;
-}
-
 .versionmodified {
     font-style: italic;
 }
@@ -766,7 +820,11 @@ div.code-block-caption code {
 table.highlighttable td.linenos,
 span.linenos,
 div.doctest > div.highlight span.gp {  /* gp: Generic.Prompt */
-    user-select: none;
+  user-select: none;
+  -webkit-user-select: text; /* Safari fallback only */
+  -webkit-user-select: none; /* Chrome/Safari */
+  -moz-user-select: none; /* Firefox */
+  -ms-user-select: none; /* IE10+ */
 }
 
 div.code-block-caption span.caption-number {
@@ -781,16 +839,6 @@ div.literal-block-wrapper {
     margin: 1em 0;
 }
 
-code.descname {
-    background-color: transparent;
-    font-weight: bold;
-    font-size: 1.2em;
-}
-
-code.descclassname {
-    background-color: transparent;
-}
-
 code.xref, a code {
     background-color: transparent;
     font-weight: bold;

docs/_static/pygments.css

@@ -1,5 +1,10 @@
+pre { line-height: 125%; }
+td.linenos .normal { color: #666666; background-color: transparent; padding-left: 5px; padding-right: 5px; }
+span.linenos { color: #666666; background-color: transparent; padding-left: 5px; padding-right: 5px; }
+td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
+span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
 .highlight .hll { background-color: #ffffcc }
-.highlight  { background: #f0f0f0; }
+.highlight { background: #f0f0f0; }
 .highlight .c { color: #60a0b0; font-style: italic } /* Comment */
 .highlight .err { border: 1px solid #FF0000 } /* Error */
 .highlight .k { color: #007020; font-weight: bold } /* Keyword */

docs/_static/searchtools.js

@@ -509,7 +509,7 @@ var Search = {
     var excerpt = ((start > 0) ? '...' : '') +
       $.trim(text.substr(start, 240)) +
       ((start + 240 - text.length) ? '...' : '');
-    var rv = $('<div class="context"></div>').text(excerpt);
+    var rv = $('<p class="context"></p>').text(excerpt);
     $.each(hlwords, function() {
       rv = rv.highlightText(this, 'highlighted');
     });