[#388] Add conf ls to get the configuration file locations

contrib/shell_comp/pgagroal_comp.bash

@@ -25,7 +25,7 @@ pgagroal_cli_completions()
                 COMPREPLY+=($(compgen -W "server prometheus" "${COMP_WORDS[2]}"))
                 ;;
 	    conf)
-		COMPREPLY+=($(compgen -W "reload get set" "${COMP_WORDS[2]}"))
+		COMPREPLY+=($(compgen -W "reload get set ls" "${COMP_WORDS[2]}"))
 		;;
 	    status)
 		COMPREPLY+=($(compgen -W "details" "${COMP_WORDS[2]}"))

contrib/shell_comp/pgagroal_comp.zsh

@@ -40,7 +40,7 @@ function _pgagroal_cli_conf()
 {
     local line
     _arguments -C \
-               "1: :(reload get set)" \
+               "1: :(reload get set ls)" \
                "*::arg:->args"
 }
 

doc/CLI.md

@@ -184,7 +184,8 @@ Manages the configuration of the running instance.
 This command requires one subcommand, that can be:
 - `reload` issue a reload of the configuration, applying at runtime any changes from the configuration files;
 - `get` provides a configuration parameter value;
-- `set` modifies a configuration parameter at runtime.
+- `set` modifies a configuration parameter at runtime;
+- `ls` prints where the configuration files are located.
 
 Command
 
@@ -205,7 +206,7 @@ pgagroal-cli conf set max_connections 25
 
 The details about how to get and set values at run-time are explained in the following.
 
-### conf get
+#### conf get
 Given a configuration setting name, provides the current value for such setting.
 
 The configuration setting name must be the same as the one used in the configuration files.
@@ -256,7 +257,7 @@ If the parameter name specified is not found or invalid, the program `pgagroal-c
 
 
 
-### conf set
+#### conf set
 Allows the setting of a configuration parameter at run-time, if possible.
 
 Examples
@@ -303,7 +304,20 @@ WARN  1 settings cannot be applied
 DEBUG pgagroal_management_write_config_set: unable to apply changes to <max_connections> -> <100>
 ```
 
+#### conf ls
 
+The command `conf ls` provides information about the location of the configuration files.
+As an example:
+
+```
+Main Configuration file:   /etc/pgagroal/pgagroal.conf
+HBA file:                  /etc/pgagroal/pgagroal_hba.conf
+Limit file:                /etc/pgagroal/pgagroal_databases.conf
+Frontend users file:       /etc/pgagroal/pgagroal_frontend_users.conf
+Admins file:               /etc/pgagroal/pgagroal_admins.conf
+Superuser file:
+Users file:                /etc/pgagroal/pgagroal_users.conf
+```
 
 ### clear
 Resets different parts of the pooler. It accepts an operational mode:

src/cli.c

@@ -66,6 +66,7 @@
 #define ACTION_RELOAD         13
 #define ACTION_CONFIG_GET     14
 #define ACTION_CONFIG_SET     15
+#define ACTION_CONFIG_LS      16
 
 static int flush(SSL* ssl, int socket, int32_t mode, char* database);
 static int enabledb(SSL* ssl, int socket, char* database);
@@ -82,6 +83,7 @@ static int switch_to(SSL* ssl, int socket, char* server);
 static int reload(SSL* ssl, int socket);
 static int config_get(SSL* ssl, int socket, char* config_key, bool verbose);
 static int config_set(SSL* ssl, int socket, char* config_key, char* config_value, bool verbose);
+static int config_ls(SSL* ssl, int socket);
 
 static void
 version(void)
@@ -134,7 +136,8 @@ usage(void)
    printf("                           - 'get' to obtain information about a runtime configuration value;\n");
    printf("                                   conf get <parameter_name>\n");
    printf("                           - 'set' to modify a configuration value;\n");
-   printf("                                   conf set <parameter_name> <parameter_value>\n");
+   printf("                                   conf set <parameter_name> <parameter_value>;\n");
+   printf("                           - 'ls'  lists the configuration files used.\n");
    printf("  clear <what>             Resets either the Prometheus statistics or the specified server.\n");
    printf("                           <what> can be\n");
    printf("                           - 'server' (default) followed by a server name\n");
@@ -431,20 +434,25 @@ main(int argc, char** argv)
       {
          action = ACTION_RELOAD;
       }
-      pgagroal_log_debug("Command: <reload>");
+      pgagroal_log_trace("Command: <reload>");
    }
    else if (parse_command(argc, argv, optind, "conf", "get", &config_key, NULL, NULL, NULL)
             || parse_deprecated_command(argc, argv, optind, "config-get", NULL, "conf get", 1, 6))
    {
       action = config_key != NULL && strlen(config_key) > 0 ? ACTION_CONFIG_GET : ACTION_UNKNOWN;
-      pgagroal_log_debug("Command: <conf get> [%s]", config_key);
+      pgagroal_log_trace("Command: <conf get> [%s]", config_key);
    }
    else if (parse_command(argc, argv, optind, "conf", "set", &config_key, NULL, &config_value, NULL)
             || parse_deprecated_command(argc, argv, optind, "config-set", NULL, "conf set", 1, 6))
    {
       // if there is no configuration key set the action to unknown, so the help screen will be printed
       action = config_key != NULL && strlen(config_key) > 0 ? ACTION_CONFIG_SET : ACTION_UNKNOWN;
-      pgagroal_log_debug("Command: <conf set> [%s] = [%s]", config_key, config_value);
+      pgagroal_log_trace("Command: <conf set> [%s] = [%s]", config_key, config_value);
+   }
+   else if (parse_command_simple(argc, argv, optind, "conf", "ls"))
+   {
+      pgagroal_log_debug("Command: <conf ls>");
+      action = ACTION_CONFIG_LS;
    }
 
    if (action != ACTION_UNKNOWN)
@@ -606,6 +614,10 @@ main(int argc, char** argv)
    {
       exit_code = config_set(s_ssl, socket, config_key, config_value, verbose);
    }
+   else if (action == ACTION_CONFIG_LS)
+   {
+      exit_code = config_ls(s_ssl, socket);
+   }
 
 done:
 
@@ -970,3 +982,27 @@ config_set(SSL* ssl, int socket, char* config_key, char* config_value, bool verb
 error:
    return EXIT_STATUS_CONNECTION_ERROR;
 }
+
+/**
+ * Asks the daemon about the configuration file location.
+ *
+ * @returns 0 on success
+ */
+static int
+config_ls(SSL* ssl, int socket)
+{
+
+   if (pgagroal_management_conf_ls(ssl, socket))
+   {
+      goto error;
+   }
+
+   if (pgagroal_management_read_conf_ls(ssl, socket))
+   {
+      goto error;
+   }
+
+   return EXIT_STATUS_OK;
+error:
+   return EXIT_STATUS_CONNECTION_ERROR;
+}

src/include/management.h

@@ -61,6 +61,7 @@ extern "C" {
 #define MANAGEMENT_REMOVE_FD          19
 #define MANAGEMENT_CONFIG_GET         20
 #define MANAGEMENT_CONFIG_SET         21
+#define MANAGEMENT_CONFIG_LS          22
 
 /**
  * Read the management header
@@ -386,6 +387,60 @@ pgagroal_management_config_set(SSL* ssl, int socket, char* config_key, char* con
 int
 pgagroal_management_write_config_set(int socket, char* config_key, char* config_value);
 
+/**
+ * Entry point for managing the `conf ls` command that
+ * will list all the configuration files used by the running
+ * daemon.
+ *
+ * @param ssl the SSL handler
+ * @param fd the socket file descriptor
+ * @returns 0 on success
+ */
+int
+pgagroal_management_conf_ls(SSL* ssl, int fd);
+
+/**
+ * Reads out of the socket the list of configuration
+ * files and prints them out to the standard output.
+ *
+ * The order of the read paths is:
+ * - configuration path
+ * - HBA path
+ * - limit path
+ * - frontend users path
+ * - admins path
+ * - Superusers path
+ * - users path
+ *
+ * @param socket the file descriptor of the open socket
+ * @param ssl the SSL handler
+ * @returns 0 on success
+ */
+int
+pgagroal_management_read_conf_ls(SSL* ssl, int socket);
+
+/**
+ * The management function responsible for sending
+ * the configuration paths into the socket.
+ *
+ * The function sends every path following the path length,
+ * that must be limited to MAX_PATH size.
+ *
+ * The order of the sent paths is:
+ * - configuration path
+ * - HBA path
+ * - limit path
+ * - frontend users path
+ * - admins path
+ * - Superusers path
+ * - users path
+ *
+ * @params socket the file descriptor of the open socket
+ * @returns 0 on success
+ */
+int
+pgagroal_management_write_conf_ls(int socket);
+
 #ifdef __cplusplus
 }
 #endif