Envoy 启动相关参数整理

本篇属于Envoy代码的阅读笔记，整理了envoy启动所使用到的参数信息，代码实现在类 OptionsImpl 中，使用了TCLAP来进行参数的行解析处理。

// 文件路径如下所示：
"source/server/options_impl.h"
"source/server/options_impl.cc"

实现逻辑在下面的构造函数中：

OptionsImpl::OptionsImpl(std::vector args,
                         const HotRestartVersionCb& hot_restart_version_cb,
                         spdlog::level::level_enum default_log_level) {
                         ......
                         // 参数会先设置一个默认值，如果envoy的启动参数里面设置了对应的参数，会替换掉这些默认数据
                         }

TCLAP的相关知识可以参考：C++ 命令行解析库TCLAP

参数列表：

序号	参数名称	参数描述	类型	默认值
1	base-id	"base ID so that multiple envoys can run on the same host if needed"	uint32_t	0
2	use-dynamic-base-id	"the server chooses a base ID dynamically. Supersedes a static base ID. May not be used when the restart epoch is non-zero."	bool	false
3	base-id-path	"path to which the base ID is written"	string	""
4	concurrency	"# of worker threads to run"	uint32_t	std::thread::hardware_concurrency()
5	config-path	"Path to configuration file"	string	""
6	config-yaml	"Inline YAML configuration, merges with the contents of --config-path"	string	""
7	bootstrap-version	"API version to parse the bootstrap config as (e.g. 3). If " "unset, all known versions will be attempted"	uint32_t	0
8	allow-unknown-fields	"allow unknown fields in static configuration (DEPRECATED)"	bool	false
9	allow-unknown-static-fields	"allow unknown fields in static configuration"	bool	false
10	reject-unknown-dynamic-fields		bool	false
11	ignore-unknown-dynamic-fields	"ignore unknown fields in dynamic configuration"	bool	false
12	admin-address-path	"Admin address path"	string	""
13	local-address-ip-version	The local  IP address version (v4 or v6)."	string	"v4"
14	log-level	log_levels_string	string	spdlog::level::level_string_views[default_log_level].data()
15	component-log-level	component_log_level_string	string	""
16	log-format	log_format_string	string	Logger::Logger::DEFAULT_LOG_FORMAT
17	log-format-escaped	"Escape c-style escape sequences in the application logs"	bool	false
18	enable-fine-grain-logging	"Logger mode: enable file level log control(Fancy Logger)or not"	bool	false
19	log-path	"Path to logfile"	string	""
20	restart-epoch	"hot restart epoch #"	uint32_t	0
21	hot-restart-version	"hot restart compatibility version"	bool	false
22	service-cluster	"Cluster name"	string	""
23	service-node	"Node name"	string	""
24	service-zone	"Zone name"	string	""
25	file-flush-interval-msec	"Interval for log flushing in msec"	uint32_t	10000ms
26	drain-time-s	"Hot restart and LDS removal drain time in seconds"	uint32_t	600ms
27	drain-strategy	"Hot restart drain sequence behaviour, one of 'gradual' (default) or 'immediate'."	string	"gradual"
28	parent-shutdown-time-s	"Hot restart parent shutdown time in seconds"	uint32_t	900ms
29	mode	"One of 'serve' (default; validate configs and then serve " "traffic normally) or 'validate' (validate configs and exit)."	string	"serve"
30	disable-hot-restart	"Disable hot restart functionality"	bool	false
31	enable-mutex-tracing	"Enable mutex contention tracing functionality"	bool	false
32	cpuset-threads	"Get the default # of worker threads from cpuset size"	bool	false
33	disable-extensions	"Comma-separated list of extensions to disable"	string	""
34	socket-path	"Path to hot restart socket file"	string	"@envoy_domain_socket"
35	socket-mode	"Socket file permission"	string	"600"
36	enable-core-dump	"Enable core dumps"	bool	false

参考：istio-proxy 1.11.2版本的envoy  代码