cleanup(outputs): adopt different style for outputs_queue params encodings

Co-authored-by: Leonardo Grasso <me@leonardograsso.com>
Signed-off-by: Melissa Kilby <melissa.kilby.oss@gmail.com>

falco.yaml

@@ -39,7 +39,8 @@
 #     json_include_tags_property
 #     buffered_outputs
 #     outputs (throttling)
-#     queue_capacity_outputs
+#     rule_matching
+#     outputs_queue
 # Falco outputs channels
 #     stdout_output
 #     syslog_output
@@ -320,7 +321,7 @@ outputs:
 # deploying it in production.
 rule_matching: first
 
-# [Experimental] `queue_capacity_outputs`
+# [Experimental] `outputs_queue`
 #
 # Falco utilizes tbb::concurrent_bounded_queue for handling outputs, and this parameter
 # allows you to customize the queue capacity. Please refer to the official documentation:
@@ -335,18 +336,17 @@ rule_matching: first
 # as a parameter.
 # However, it will not address the root cause of the event pipe not keeping up.
 # 
-# `items`: the maximum number of items allowed in the queue, defaulting to 0. This means that
-# the queue is unbounded.
+# `capacity`: the maximum number of items allowed in the queue, defaulting to 0. This means that
+# the queue remains unbounded aka this setting is disabled.
 # You can experiment with values greater or smaller than the anchor value 1000000.
 # 
 # `recovery`: the strategy to follow when the queue becomes filled up. This also applies when
 # the queue is unbounded, and all available memory on the system is consumed.
-# recovery: 0 means continue.
-# recovery: 1 means simply exit (default behavior).
-# recovery: 2 means empty the queue and then continue.
-queue_capacity_outputs:
-  items: 0
-  recovery: 1
+# `exit` is default, `continue` does nothing special and `empty` empties the queue and then
+# continues.
+outputs_queue:
+  capacity: 0
+  recovery: exit
 
 
 ##########################

userspace/engine/falco_common.cpp

@@ -27,10 +27,18 @@ static std::vector<std::string> priority_names = {
 	"Debug"
 };
 
+<<<<<<< HEAD
 static std::vector<std::string> rule_matching_names = {
 	"first",
 	"all"
 };
+=======
+static std::vector<std::string> outputs_recovery_names = {
+		"continue",
+		"exit",
+		"empty",
+	};
+>>>>>>> 92bd5767 (cleanup(outputs): adopt different style for outputs_queue params encodings)
 
 bool falco_common::parse_priority(std::string v, priority_type& out)
 {
@@ -59,6 +67,19 @@ falco_common::priority_type falco_common::parse_priority(std::string v)
 	return out;
 }
 
+bool falco_common::parse_recovery(std::string v, outputs_recovery_type& out)
+{
+	for (size_t i = 0; i < outputs_recovery_names.size(); i++)
+	{
+		if (!strcasecmp(v.c_str(), outputs_recovery_names[i].c_str()))
+		{
+			out = (outputs_recovery_type) i;
+			return true;
+		}
+	}
+	return false;
+}
+
 bool falco_common::format_priority(priority_type v, std::string& out, bool shortfmt)
 {
 	if ((size_t) v < priority_names.size())

userspace/engine/falco_common.h

@@ -21,6 +21,8 @@ limitations under the License.
 #include <mutex>
 #include <sinsp.h>
 
+#define DEFAULT_OUTPUTS_QUEUE_CAPACITY 0
+
 //
 // Most falco_* classes can throw exceptions. Unless directly related
 // to low-level failures like inability to open file, etc, they will
@@ -52,6 +54,13 @@ struct falco_exception : std::exception
 
 namespace falco_common
 {
+
+	enum outputs_recovery_type {
+		RECOVERY_CONTINUE = 0,  /* queue_capacity_outputs recovery strategy of continuing on. */
+		RECOVERY_EXIT = 1,  /* queue_capacity_outputs recovery strategy of exiting, self OOM kill. */
+		RECOVERY_EMPTY = 2,  /* queue_capacity_outputs recovery strategy of emptying queue then continuing. */
+	};
+
 	const std::string syscall_source = sinsp_syscall_event_source_name;
 
 	// Same as numbers/indices into the above vector
@@ -69,6 +78,7 @@ namespace falco_common
 	
 	bool parse_priority(std::string v, priority_type& out);
 	priority_type parse_priority(std::string v);
+	bool parse_recovery(std::string v, outputs_recovery_type& out);
 	bool format_priority(priority_type v, std::string& out, bool shortfmt=false);
 	std::string format_priority(priority_type v, bool shortfmt=false);
 

userspace/falco/app/actions/init_outputs.cpp

@@ -63,8 +63,8 @@ falco::app::run_result falco::app::actions::init_outputs(falco::app::state& s)
 		s.config->m_json_include_tags_property,
 		s.config->m_output_timeout,
 		s.config->m_buffered_outputs,
-		s.config->m_queue_capacity_outputs_items,
-		s.config->m_queue_capacity_outputs_recovery,
+		s.config->m_outputs_queue_capacity,
+		s.config->m_outputs_queue_recovery,
 		s.config->m_time_format_iso_8601,
 		hostname));
 

userspace/falco/configuration.cpp

@@ -28,7 +28,6 @@ limitations under the License.
 #include "falco_utils.h"
 
 #include "configuration.h"
-#include "configuration_aux.h"
 #include "logger.h"
 #include "banned.h" // This raises a compilation error when certain functions are used
 
@@ -41,8 +40,8 @@ falco_configuration::falco_configuration():
 	m_rule_matching(falco_common::rule_matching::FIRST),
 	m_watch_config_files(true),
 	m_buffered_outputs(false),
-	m_queue_capacity_outputs_items(DEFAULT_ITEMS_QUEUE_CAPAXITY_OUTPUTS),
-	m_queue_capacity_outputs_recovery(RECOVERY_EXIT),
+	m_outputs_queue_capacity(DEFAULT_OUTPUTS_QUEUE_CAPACITY),
+	m_outputs_queue_recovery(falco_common::RECOVERY_EXIT),
 	m_time_format_iso_8601(false),
 	m_output_timeout(2000),
 	m_grpc_enabled(false),
@@ -284,8 +283,13 @@ void falco_configuration::load_yaml(const std::string& config_name, const yaml_h
 	}
 
 	m_buffered_outputs = config.get_scalar<bool>("buffered_outputs", false);
-	m_queue_capacity_outputs_items = config.get_scalar<size_t>("queue_capacity_outputs.items", DEFAULT_ITEMS_QUEUE_CAPAXITY_OUTPUTS);
-	m_queue_capacity_outputs_recovery = config.get_scalar<uint32_t>("queue_capacity_outputs.recovery", RECOVERY_EXIT);
+	m_outputs_queue_capacity = config.get_scalar<size_t>("outputs_queue.capacity", DEFAULT_OUTPUTS_QUEUE_CAPACITY);
+	std::string recovery = config.get_scalar<std::string>("outputs_queue.recovery", "exit");
+	if (!falco_common::parse_recovery(recovery, m_outputs_queue_recovery))
+	{
+		throw std::logic_error("Unknown recovery \"" + recovery + "\"--must be one of exit, continue, empty");
+	}
+
 	m_time_format_iso_8601 = config.get_scalar<bool>("time_format_iso_8601", false);
 
 	m_webserver_enabled = config.get_scalar<bool>("webserver.enabled", false);

userspace/falco/configuration.h

@@ -72,8 +72,8 @@ public:
 
 	bool m_watch_config_files;
 	bool m_buffered_outputs;
-	size_t m_queue_capacity_outputs_items;
-	uint32_t m_queue_capacity_outputs_recovery;
+	size_t m_outputs_queue_capacity;
+	falco_common::outputs_recovery_type m_outputs_queue_recovery;
 	bool m_time_format_iso_8601;
 	uint32_t m_output_timeout;
 

userspace/falco/configuration_aux.h

@@ -1,22 +0,0 @@
-/*
-Copyright (C) 2023 The Falco Authors.
-Licensed 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.
-*/
-
-#pragma once
-
-#define DEFAULT_ITEMS_QUEUE_CAPAXITY_OUTPUTS 0
-
-enum outputs_recovery_code {
-	RECOVERY_DROP_CURRENT = 0,  /* queue_capacity_outputs recovery strategy of continuing on. */
-	RECOVERY_EXIT = 1,  /* queue_capacity_outputs recovery strategy of exiting, self OOM kill. */
-	RECOVERY_EMPTY = 2,  /* queue_capacity_outputs recovery strategy of emptying queue then continuing. */
-};

userspace/falco/falco_outputs.cpp

@@ -20,7 +20,6 @@ limitations under the License.
 
 #include "falco_outputs.h"
 #include "config_falco.h"
-#include "configuration_aux.h"
 
 #include "formats.h"
 #include "logger.h"
@@ -47,8 +46,8 @@ falco_outputs::falco_outputs(
 	bool json_include_tags_property,
 	uint32_t timeout,
 	bool buffered,
-	size_t queue_capacity_outputs_items,
-	uint32_t queue_capacity_outputs_recovery,
+	size_t outputs_queue_capacity,
+	falco_common::outputs_recovery_type outputs_queue_recovery,
 	bool time_format_iso_8601,
 	const std::string& hostname)
 {
@@ -68,12 +67,11 @@ falco_outputs::falco_outputs(
 	}
 #ifndef __EMSCRIPTEN__
 	m_worker_thread = std::thread(&falco_outputs::worker, this);
-	if (queue_capacity_outputs_items > 0)
+	if (outputs_queue_capacity > 0)
 	{
-		m_queue.set_capacity(queue_capacity_outputs_items);
+		m_queue.set_capacity(outputs_queue_capacity);
 	}
-
-	m_recovery = queue_capacity_outputs_recovery;
+	m_recovery = outputs_queue_recovery;
 #endif
 }
 
@@ -292,12 +290,13 @@ inline void falco_outputs::push(const ctrl_msg& cmsg)
 	{
 		switch (m_recovery)
 		{
-		case RECOVERY_EXIT:
+		case falco_common::RECOVERY_EXIT:
 			fprintf(stderr, "Fatal error: Output queue out of memory. Exiting ... \n");
 			exit(EXIT_FAILURE);
-		case RECOVERY_EMPTY:
+		case falco_common::RECOVERY_EMPTY:
 			fprintf(stderr, "Output queue out of memory. Empty queue and continue ... \n");
 			m_queue.empty();
+			break;
 		default:
 			fprintf(stderr, "Output queue out of memory. Continue on ... \n");
 			break;

userspace/falco/falco_outputs.h

@@ -48,8 +48,8 @@ public:
 		bool json_include_tags_property,
 		uint32_t timeout,
 		bool buffered,
-		size_t queue_capacity_outputs_items,
-		uint32_t queue_capacity_outputs_recovery,
+		size_t outputs_queue_capacity,
+		falco_common::outputs_recovery_type outputs_queue_recovery,
 		bool time_format_iso_8601,
 		const std::string& hostname);
 

userspace/falco/stats_writer.cpp

@@ -91,9 +91,9 @@ stats_writer::stats_writer(
 	m_config = config;
 	// capacity and controls should not be relevant for stats outputs, adopt capacity
 	// for completeness, but do not implement config recovery strategies.
-	if (config->m_queue_capacity_outputs_items > 0)
+	if (config->m_outputs_queue_capacity > 0)
 	{
-		m_queue.set_capacity(config->m_queue_capacity_outputs_items);
+		m_queue.set_capacity(config->m_outputs_queue_capacity);
 	}
 	if (config->m_metrics_enabled)
 	{