block_errors: Fix plugin message handling

plugins/experimental/block_errors/block_errors.cc

@@ -20,6 +20,7 @@
 #include <unordered_map>
 #include <limits>
 #include <swoc/IPAddr.h>
+#include <swoc/TextView.h>
 #include <swoc/bwf_ip.h>
 #include <unistd.h>
 #include <arpa/inet.h>
@@ -37,31 +38,46 @@ static bool     enabled             = true;
 
 //-------------------------------------------------------------------------
 static int
-msg_hook(TSCont * /* contp ATS_UNUSED */, TSEvent /* event ATS_UNUSED */, void *edata)
+msg_hook(TSCont * /* contp ATS_UNUSED */, TSEvent event, void *edata)
 {
-  TSPluginMsg     *msg = static_cast<TSPluginMsg *>(edata);
-  std::string_view tag(static_cast<const char *>(msg->tag));
-  std::string_view data(static_cast<const char *>(msg->data));
+  if (event != TS_EVENT_LIFECYCLE_MSG) {
+    TSError("block_errors: unexpected event %d", event);
+    return TS_EVENT_NONE;
+  }
+
+  TSPluginMsg   *msg = static_cast<TSPluginMsg *>(edata);
+  swoc::TextView message{msg->tag, strlen(msg->tag)};
+  swoc::TextView target  = message.take_prefix_at('.');
+  swoc::TextView command = message;
+
+  // Filter for messages meant for this plugin.
+  if (target != "block_errors") {
+    Dbg(dbg_ctl, "msg_hook: message for a different plugin: %.*s", static_cast<int>(target.size()), target.data());
+    return TS_EVENT_NONE;
+  }
+
+  swoc::TextView data{static_cast<const char *>(msg->data), msg->data_size};
 
-  Dbg(dbg_ctl, "msg_hook: tag=%s data=%s", tag.data(), data.data());
+  Dbg(dbg_ctl, "msg_hook: command=%.*s data=%.*s", static_cast<int>(command.size()), command.data(), static_cast<int>(data.size()),
+      data.data());
 
-  if (tag == "block_errors.enabled") {
+  if (command == "enabled") {
     enabled = static_cast<bool>(atoi(data.data()));
-  } else if (tag == "block_errors.limit") {
+  } else if (command == "limit") {
     RESET_LIMIT = atoi(data.data());
-  } else if (tag == "block_errors.cycles") {
+  } else if (command == "cycles") {
     TIMEOUT_CYCLES = atoi(data.data());
-  } else if (tag == "block_errors.shutdown") {
+  } else if (command == "shutdown") {
     shutdown_connection = static_cast<bool>(atoi(data.data()));
   } else {
-    Dbg(dbg_ctl, "msg_hook: unknown message tag '%s'", tag.data());
-    TSError("block_errors: unknown message tag '%s'", tag.data());
+    Dbg(dbg_ctl, "msg_hook: unknown command '%.*s'", static_cast<int>(command.size()), command.data());
+    TSError("block_errors: unknown command '%.*s'", static_cast<int>(command.size()), command.data());
   }
 
   Dbg(dbg_ctl, "reset limit: %d per minute, timeout limit: %d minutes, shutdown connection: %d enabled: %d", RESET_LIMIT,
       TIMEOUT_CYCLES, shutdown_connection, enabled);
 
-  return 0;
+  return TS_EVENT_NONE;
 }
 
 //-------------------------------------------------------------------------

tests/gold_tests/pluginTest/block_errors/block_errors.test.py

@@ -0,0 +1,176 @@
+"""
+Verify block_errors plugin message handling.
+"""
+#  Licensed to the Apache Software Foundation (ASF) under one
+#  or more contributor license agreements.  See the NOTICE file
+#  distributed with this work for additional information
+#  regarding copyright ownership.  The ASF licenses this file
+#  to you under the Apache License, Version 2.0 (the
+#  "License"); you may not use this file except in compliance
+#  with the License.  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+Test.Summary = '''
+Verify block_errors plugin message handling via traffic_ctl.
+'''
+
+Test.SkipUnless(Condition.PluginExists('block_errors.so'),)
+
+# Define ATS and configure it.
+ts = Test.MakeATSProcess("ts")
+
+ts.Disk.records_config.update({
+    'proxy.config.diags.debug.enabled': 1,
+    'proxy.config.diags.debug.tags': 'block_errors',
+})
+
+# Configure block_errors plugin with initial values.
+ts.Disk.plugin_config.AddLine('block_errors.so')
+
+# Verify the plugin loads.
+ts.Disk.diags_log.Content = Testers.ContainsExpression(
+    "loading plugin.*block_errors.so", "Verify the block_errors plugin got loaded.")
+
+#
+# Test 1: Verify the plugin starts with default values.
+#
+tr = Test.AddTestRun("Verify plugin starts with default values.")
+tr.Processes.Default.Command = "echo verifying plugin starts with default values"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.StartBefore(ts)
+tr.StillRunningAfter = ts
+
+# Verify the default values are logged at startup.
+ts.Disk.traffic_out.Content = Testers.ContainsExpression(
+    "reset limit: 1000 per minute, timeout limit: 4 minutes, shutdown connection: 0 enabled: 1",
+    "Verify block_errors starts with default values.")
+
+#
+# Test 2: Verify changing the 'enabled' setting via traffic_ctl.
+#
+tr = Test.AddTestRun("Verify changing 'enabled' via traffic_ctl.")
+tr.Processes.Default.Command = "traffic_ctl plugin msg block_errors.enabled 0"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.Env = ts.Env
+tr.StillRunningAfter = ts
+
+tr = Test.AddTestRun("Await the enabled change.")
+tr.Processes.Default.Command = "echo awaiting enabled change"
+tr.Processes.Default.ReturnCode = 0
+await_enabled = tr.Processes.Process('await_enabled', 'sleep 30')
+await_enabled.Ready = When.FileContains(ts.Disk.traffic_out.Name, "msg_hook: command=enabled data=0")
+tr.Processes.Default.StartBefore(await_enabled)
+
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "msg_hook: command=enabled data=0", "Verify block_errors received the enabled command.")
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "reset limit: 1000 per minute, timeout limit: 4 minutes, shutdown connection: 0 enabled: 0",
+    "Verify block_errors applied the enabled=0 setting.")
+
+#
+# Test 3: Verify changing the 'limit' setting via traffic_ctl.
+#
+tr = Test.AddTestRun("Verify changing 'limit' via traffic_ctl.")
+tr.Processes.Default.Command = "traffic_ctl plugin msg block_errors.limit 500"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.Env = ts.Env
+tr.StillRunningAfter = ts
+
+tr = Test.AddTestRun("Await the limit change.")
+tr.Processes.Default.Command = "echo awaiting limit change"
+tr.Processes.Default.ReturnCode = 0
+await_limit = tr.Processes.Process('await_limit', 'sleep 30')
+await_limit.Ready = When.FileContains(ts.Disk.traffic_out.Name, "msg_hook: command=limit data=500")
+tr.Processes.Default.StartBefore(await_limit)
+
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "msg_hook: command=limit data=500", "Verify block_errors received the limit command.")
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "reset limit: 500 per minute", "Verify block_errors applied the limit=500 setting.")
+
+#
+# Test 4: Verify changing the 'cycles' setting via traffic_ctl.
+#
+tr = Test.AddTestRun("Verify changing 'cycles' via traffic_ctl.")
+tr.Processes.Default.Command = "traffic_ctl plugin msg block_errors.cycles 8"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.Env = ts.Env
+tr.StillRunningAfter = ts
+
+tr = Test.AddTestRun("Await the cycles change.")
+tr.Processes.Default.Command = "echo awaiting cycles change"
+tr.Processes.Default.ReturnCode = 0
+await_cycles = tr.Processes.Process('await_cycles', 'sleep 30')
+await_cycles.Ready = When.FileContains(ts.Disk.traffic_out.Name, "msg_hook: command=cycles data=8")
+tr.Processes.Default.StartBefore(await_cycles)
+
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "msg_hook: command=cycles data=8", "Verify block_errors received the cycles command.")
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "timeout limit: 8 minutes", "Verify block_errors applied the cycles=8 setting.")
+
+#
+# Test 5: Verify changing the 'shutdown' setting via traffic_ctl.
+#
+tr = Test.AddTestRun("Verify changing 'shutdown' via traffic_ctl.")
+tr.Processes.Default.Command = "traffic_ctl plugin msg block_errors.shutdown 1"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.Env = ts.Env
+tr.StillRunningAfter = ts
+
+tr = Test.AddTestRun("Await the shutdown change.")
+tr.Processes.Default.Command = "echo awaiting shutdown change"
+tr.Processes.Default.ReturnCode = 0
+await_shutdown = tr.Processes.Process('await_shutdown', 'sleep 30')
+await_shutdown.Ready = When.FileContains(ts.Disk.traffic_out.Name, "msg_hook: command=shutdown data=1")
+tr.Processes.Default.StartBefore(await_shutdown)
+
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "msg_hook: command=shutdown data=1", "Verify block_errors received the shutdown command.")
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "shutdown connection: 1", "Verify block_errors applied the shutdown=1 setting.")
+
+#
+# Test 6: Verify an unknown command is handled gracefully.
+#
+tr = Test.AddTestRun("Verify unknown command is handled gracefully.")
+tr.Processes.Default.Command = "traffic_ctl plugin msg block_errors.unknown_command test"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.Env = ts.Env
+tr.StillRunningAfter = ts
+
+tr = Test.AddTestRun("Await the unknown command response.")
+tr.Processes.Default.Command = "echo awaiting unknown command response"
+tr.Processes.Default.ReturnCode = 0
+await_unknown = tr.Processes.Process('await_unknown', 'sleep 30')
+await_unknown.Ready = When.FileContains(ts.Disk.traffic_out.Name, "msg_hook: unknown command 'unknown_command'")
+tr.Processes.Default.StartBefore(await_unknown)
+
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "msg_hook: unknown command 'unknown_command'", "Verify block_errors logs unknown commands.")
+
+#
+# Test 7: Verify messages for other plugins are ignored.
+#
+tr = Test.AddTestRun("Verify messages for other plugins are ignored.")
+tr.Processes.Default.Command = "traffic_ctl plugin msg other_plugin.command test"
+tr.Processes.Default.ReturnCode = 0
+tr.Processes.Default.Env = ts.Env
+tr.StillRunningAfter = ts
+
+tr = Test.AddTestRun("Await the other plugin message response.")
+tr.Processes.Default.Command = "echo awaiting other plugin message response"
+tr.Processes.Default.ReturnCode = 0
+await_other = tr.Processes.Process('await_other', 'sleep 30')
+await_other.Ready = When.FileContains(ts.Disk.traffic_out.Name, "msg_hook: message for a different plugin: other_plugin")
+tr.Processes.Default.StartBefore(await_other)
+
+ts.Disk.traffic_out.Content += Testers.ContainsExpression(
+    "msg_hook: message for a different plugin: other_plugin", "Verify block_errors ignores messages for other plugins.")