Port ACLs, Management API and Health commands (#4969)

##### Summary
fixes #2673 
fixes #2149
fixes #5017 
fixes #3830 
fixes #3187 
fixes #5154

Implements a command API for health which will accept commands via a socket to selectively suppress health checks. 

Allows different ports to accept different request types  (streaming, dashboard, api, registry, netdata.conf, badges, management)

Removes support for multi-threaded and single-threaded web servers.

##### Component Name
health, daemon

1 files changed, 2 insertions, 19 deletions

diff --git a/daemon/main.c b/daemon/main.c
index b2c4c80bf5..1ec5f6ed5a 100644
--- a/daemon/main.c
+++ b/daemon/main.c
@@ -67,8 +67,6 @@ struct netdata_static_thread static_threads[] = {
 
         // common plugins for all systems
     {"BACKENDS",             NULL,                    NULL,         1, NULL, NULL, backends_main},
-    {"WEB_SERVER[multi]",    NULL,                    NULL,         1, NULL, NULL, socket_listen_main_multi_threaded},
-    {"WEB_SERVER[single]",   NULL,                    NULL,         0, NULL, NULL, socket_listen_main_single_threaded},
     {"WEB_SERVER[static1]",  NULL,                    NULL,         0, NULL, NULL, socket_listen_main_static_threaded},
     {"STREAM",               NULL,                    NULL,         0, NULL, NULL, rrdpush_sender_thread},
 
@@ -81,18 +79,10 @@ struct netdata_static_thread static_threads[] = {
 void web_server_threading_selection(void) {
     web_server_mode = web_server_mode_id(config_get(CONFIG_SECTION_WEB, "mode", web_server_mode_name(web_server_mode)));
 
-    int multi_threaded = (web_server_mode == WEB_SERVER_MODE_MULTI_THREADED);
-    int single_threaded = (web_server_mode == WEB_SERVER_MODE_SINGLE_THREADED);
     int static_threaded = (web_server_mode == WEB_SERVER_MODE_STATIC_THREADED);
 
     int i;
     for (i = 0; static_threads[i].name; i++) {
-        if (static_threads[i].start_routine == socket_listen_main_multi_threaded)
-            static_threads[i].enabled = multi_threaded;
-
-        if (static_threads[i].start_routine == socket_listen_main_single_threaded)
-            static_threads[i].enabled = single_threaded;
-
         if (static_threads[i].start_routine == socket_listen_main_static_threaded)
             static_threads[i].enabled = static_threaded;
     }
@@ -113,6 +103,8 @@ void web_server_config_options(void) {
     web_allow_registry_from    = simple_pattern_create(config_get(CONFIG_SECTION_REGISTRY, "allow from", "*"), NULL, SIMPLE_PATTERN_EXACT);
     web_allow_streaming_from   = simple_pattern_create(config_get(CONFIG_SECTION_WEB, "allow streaming from", "*"), NULL, SIMPLE_PATTERN_EXACT);
     web_allow_netdataconf_from = simple_pattern_create(config_get(CONFIG_SECTION_WEB, "allow netdata.conf from", "localhost fd* 10.* 192.168.* 172.16.* 172.17.* 172.18.* 172.19.* 172.20.* 172.21.* 172.22.* 172.23.* 172.24.* 172.25.* 172.26.* 172.27.* 172.28.* 172.29.* 172.30.* 172.31.*"), NULL, SIMPLE_PATTERN_EXACT);
+    web_allow_mgmt_from        = simple_pattern_create(config_get(CONFIG_SECTION_WEB, "allow management from", "localhost"), NULL, SIMPLE_PATTERN_EXACT);
+
 
 #ifdef NETDATA_WITH_ZLIB
     web_enable_gzip = config_get_boolean(CONFIG_SECTION_WEB, "enable gzip compression", web_enable_gzip);
@@ -367,13 +359,6 @@ void log_init(void) {
 }
 
 static void backwards_compatible_config() {
-    // allow existing configurations to work with the current version of netdata
-
-    if(config_exists(CONFIG_SECTION_GLOBAL, "multi threaded web server")) {
-        int mode = config_get_boolean(CONFIG_SECTION_GLOBAL, "multi threaded web server", 1);
-        web_server_mode = (mode)?WEB_SERVER_MODE_MULTI_THREADED:WEB_SERVER_MODE_SINGLE_THREADED;
-    }
-
     // move [global] options to the [web] section
     config_move(CONFIG_SECTION_GLOBAL, "http port listen backlog",
                 CONFIG_SECTION_WEB,    "listen backlog");
@@ -876,7 +861,6 @@ int main(int argc, char **argv) {
                                 load_netdata_conf(NULL, 0);
                             }
 
-                            backwards_compatible_config();
                             get_netdata_configured_variables();
 
                             const char *section = argv[optind];
@@ -1056,7 +1040,6 @@ int main(int argc, char **argv) {
 
     rrd_init(netdata_configured_hostname);
 
-
     // ------------------------------------------------------------------------
     // enable log flood protection