Add runtime status/control of logging (#419)

- Feature: New endpoint `/admin/logs` to query status of logging and log file locations and cache logging
  - `enablewritelog`=`true`/`false` parameter to control cache write logging
  - `enableaccesslog`=`true`/`false` parameter to control cache access logging
  - `loglevel` = `trace`/`debug`/`info`/`warning`/`error`
- Feature: New zen command `logs` to query/control zen logging
  - No arguments gives status of logging and paths to log files
  - `--cache-write-log` `enable`/`disable` to control cache write logging
  - `--cache-access-log` `enable`/`disable` to control cache access logging
  - `--loglevel` `trace`/`debug`/`info`/`warning`/`error` to set debug level

1 files changed, 19 insertions, 0 deletions

diff --git a/src/zen/cmds/admin_cmd.h b/src/zen/cmds/admin_cmd.h
index 6caab7138..873c230d9 100644
--- a/src/zen/cmds/admin_cmd.h
+++ b/src/zen/cmds/admin_cmd.h
@@ -73,4 +73,23 @@ private:
 	bool			 m_Cancel = 0;
 };
 
+////////////////////////////////////////////
+
+class LoggingCommand : public ZenCmdBase
+{
+public:
+	LoggingCommand();
+	~LoggingCommand();
+
+	virtual int				  Run(const ZenCliOptions& GlobalOptions, int argc, char** argv) override;
+	virtual cxxopts::Options& Options() override { return m_Options; }
+
+private:
+	cxxopts::Options m_Options{"logs", "Show/control zen logging"};
+	std::string		 m_HostName;
+	std::string		 m_CacheWriteLog;
+	std::string		 m_CacheAccessLog;
+	std::string		 m_SetLogLevel;
+};
+
 }  // namespace zen