Configuration persistence.

Now configuration survives server reloads.

6 files changed, 234 insertions, 2 deletions

diff --git a/src/nxt_controller.c b/src/nxt_controller.c
index e41452a3..1a595bcf 100644
--- a/src/nxt_controller.c
+++ b/src/nxt_controller.c
@@ -71,6 +71,8 @@ static void nxt_controller_process_request(nxt_task_t *task,
     nxt_controller_request_t *req);
 static void nxt_controller_conf_handler(nxt_task_t *task,
     nxt_port_recv_msg_t *msg, void *data);
+static void nxt_controller_conf_store(nxt_task_t *task,
+    nxt_conf_value_t *conf);
 static void nxt_controller_response(nxt_task_t *task,
     nxt_controller_request_t *req, nxt_controller_response_t *resp);
 static u_char *nxt_controller_date(u_char *buf, nxt_realtime_t *now,
@@ -86,6 +88,7 @@ static nxt_http_fields_hash_entry_t  nxt_controller_request_fields[] = {
 
 static nxt_http_fields_hash_t  *nxt_controller_fields_hash;
 
+static nxt_uint_t              nxt_controller_listening;
 static nxt_controller_conf_t   nxt_controller_conf;
 static nxt_queue_t             nxt_controller_waiting_requests;
 
@@ -115,7 +118,10 @@ nxt_port_handler_t  nxt_controller_process_port_handlers[] = {
 nxt_int_t
 nxt_controller_start(nxt_task_t *task, void *data)
 {
+    nxt_mp_t                *mp;
+    nxt_str_t               *json;
     nxt_runtime_t           *rt;
+    nxt_conf_value_t        *conf;
     nxt_http_fields_hash_t  *hash;
 
     rt = task->thread->runtime;
@@ -129,6 +135,42 @@ nxt_controller_start(nxt_task_t *task, void *data)
     nxt_controller_fields_hash = hash;
     nxt_queue_init(&nxt_controller_waiting_requests);
 
+    json = data;
+
+    if (json->length == 0) {
+        return NXT_OK;
+    }
+
+    mp = nxt_mp_create(1024, 128, 256, 32);
+    if (nxt_slow_path(mp == NULL)) {
+        return NXT_ERROR;
+    }
+
+    conf = nxt_conf_json_parse_str(mp, json);
+    nxt_free(json->start);
+
+    if (nxt_slow_path(conf == NULL)) {
+        nxt_log(task, NXT_LOG_ALERT,
+                "failed to restore previous configuration: "
+                "file is corrupted or not enough memory");
+
+        nxt_mp_destroy(mp);
+        return NXT_OK;
+    }
+
+    if (nxt_slow_path(nxt_conf_validate(conf) != NXT_OK)) {
+        nxt_log(task, NXT_LOG_ALERT,
+                "failed to restore previous configuration: "
+                "invalid configuration");
+
+        nxt_mp_destroy(mp);
+        return NXT_OK;
+    }
+
+
+    nxt_controller_conf.root = conf;
+    nxt_controller_conf.pool = mp;
+
     return NXT_OK;
 }
 
@@ -173,6 +215,8 @@ nxt_controller_process_new_port_handler(nxt_task_t *task,
     if (nxt_slow_path(nxt_listen_event(task, rt->controller_socket) == NULL)) {
         nxt_abort();
     }
+
+    nxt_controller_listening = 1;
 }
 
 
@@ -208,13 +252,29 @@ static void
 nxt_controller_conf_init_handler(nxt_task_t *task, nxt_port_recv_msg_t *msg,
     void *data)
 {
+    nxt_runtime_t  *rt;
+
     if (msg->port_msg.type != NXT_PORT_MSG_RPC_READY) {
+        nxt_log(task, NXT_LOG_ALERT, "failed to apply previous configuration");
+
         nxt_mp_destroy(nxt_controller_conf.pool);
 
         if (nxt_slow_path(nxt_controller_conf_default() != NXT_OK)) {
             nxt_abort();
         }
     }
+
+    if (nxt_controller_listening == 0) {
+        rt = task->thread->runtime;
+
+        if (nxt_slow_path(nxt_listen_event(task, rt->controller_socket)
+                          == NULL))
+        {
+            nxt_abort();
+        }
+
+        nxt_controller_listening = 1;
+    }
 }
 
 
@@ -926,6 +986,8 @@ nxt_controller_conf_handler(nxt_task_t *task, nxt_port_recv_msg_t *msg,
 
         nxt_controller_conf = req->conf;
 
+        nxt_controller_conf_store(task, req->conf.root);
+
         resp.status = 200;
         resp.title = (u_char *) "Reconfiguration done.";
 
@@ -951,6 +1013,31 @@ nxt_controller_conf_handler(nxt_task_t *task, nxt_port_recv_msg_t *msg,
 
 
 static void
+nxt_controller_conf_store(nxt_task_t *task, nxt_conf_value_t *conf)
+{
+    size_t         size;
+    nxt_buf_t      *b;
+    nxt_port_t     *main_port;
+    nxt_runtime_t  *rt;
+
+    rt = task->thread->runtime;
+
+    main_port = rt->port_by_type[NXT_PROCESS_MAIN];
+
+    size = nxt_conf_json_length(conf, NULL);
+
+    b = nxt_buf_mem_alloc(main_port->mem_pool, size, 0);
+
+    if (nxt_fast_path(b != NULL)) {
+        b->mem.free = nxt_conf_json_print(b->mem.free, conf, NULL);
+
+        (void) nxt_port_socket_write(task, main_port, NXT_PORT_MSG_CONF_STORE,
+                                     -1, 0, -1, b);
+    }
+}
+
+
+static void
 nxt_controller_response(nxt_task_t *task, nxt_controller_request_t *req,
     nxt_controller_response_t *resp)
 {
diff --git a/src/nxt_main_process.c b/src/nxt_main_process.c
index ded19055..7748d07f 100644
--- a/src/nxt_main_process.c
+++ b/src/nxt_main_process.c
@@ -49,6 +49,8 @@ static nxt_int_t nxt_main_listening_socket(nxt_sockaddr_t *sa,
 static void nxt_main_port_modules_handler(nxt_task_t *task,
     nxt_port_recv_msg_t *msg);
 static int nxt_cdecl nxt_app_lang_compare(const void *v1, const void *v2);
+static void nxt_main_port_conf_store_handler(nxt_task_t *task,
+    nxt_port_recv_msg_t *msg);
 
 
 const nxt_sig_event_t  nxt_main_process_signals[] = {
@@ -224,6 +226,7 @@ static nxt_port_handler_t  nxt_main_process_port_handlers[] = {
     nxt_port_main_start_worker_handler,
     nxt_main_port_socket_handler,
     nxt_main_port_modules_handler,
+    nxt_main_port_conf_store_handler,
     nxt_port_rpc_handler,
     nxt_port_rpc_handler,
 };
@@ -295,8 +298,47 @@ nxt_main_process_title(nxt_task_t *task)
 static nxt_int_t
 nxt_main_start_controller_process(nxt_task_t *task, nxt_runtime_t *rt)
 {
+    ssize_t             n;
+    nxt_int_t           ret;
+    nxt_str_t           conf;
+    nxt_file_t          file;
+    nxt_file_info_t     fi;
     nxt_process_init_t  *init;
 
+    conf.length = 0;
+
+    nxt_memzero(&file, sizeof(nxt_file_t));
+
+    file.name = (nxt_file_name_t *) rt->conf;
+
+    if (nxt_file_open(task, &file, NXT_FILE_RDONLY, NXT_FILE_OPEN, 0) == NXT_OK) {
+
+        if (nxt_fast_path(nxt_file_info(&file, &fi) == NXT_OK
+                          && nxt_is_file(&fi)))
+        {
+            conf.length = nxt_file_size(&fi);
+            conf.start = nxt_malloc(conf.length);
+
+            if (nxt_slow_path(conf.start == NULL)) {
+                nxt_file_close(task, &file);
+                return NXT_ERROR;
+            }
+
+            n = nxt_file_read(&file, conf.start, conf.length, 0);
+
+            if (nxt_slow_path(n != (ssize_t) conf.length)) {
+                conf.length = 0;
+                nxt_free(conf.start);
+
+                nxt_log(task, NXT_LOG_ALERT,
+                        "failed to restore previous configuration: "
+                        "cannot read the file");
+            }
+        }
+
+        nxt_file_close(task, &file);
+    }
+
     init = nxt_malloc(sizeof(nxt_process_init_t));
     if (nxt_slow_path(init == NULL)) {
         return NXT_ERROR;
@@ -308,11 +350,17 @@ nxt_main_start_controller_process(nxt_task_t *task, nxt_runtime_t *rt)
     init->port_handlers = nxt_controller_process_port_handlers;
     init->signals = nxt_worker_process_signals;
     init->type = NXT_PROCESS_CONTROLLER;
-    init->data = rt;
+    init->data = &conf;
     init->stream = 0;
     init->restart = 1;
 
-    return nxt_main_create_worker_process(task, rt, init);
+    ret = nxt_main_create_worker_process(task, rt, init);
+
+    if (ret == NXT_OK && conf.length != 0) {
+        nxt_free(conf.start);
+    }
+
+    return ret;
 }
 
 
@@ -1054,3 +1102,51 @@ nxt_app_lang_compare(const void *v1, const void *v2)
 
     return -n;
 }
+
+
+static void
+nxt_main_port_conf_store_handler(nxt_task_t *task, nxt_port_recv_msg_t *msg)
+{
+    ssize_t        n, size;
+    nxt_buf_t      *b;
+    nxt_int_t      ret;
+    nxt_file_t     file;
+    nxt_runtime_t  *rt;
+
+    nxt_memzero(&file, sizeof(nxt_file_t));
+
+    rt = task->thread->runtime;
+
+    file.name = (nxt_file_name_t *) rt->conf_tmp;
+
+    if (nxt_slow_path(nxt_file_open(task, &file, NXT_FILE_WRONLY,
+                                    NXT_FILE_TRUNCATE, NXT_FILE_OWNER_ACCESS)
+                      != NXT_OK))
+    {
+        goto error;
+    }
+
+    for (b = msg->buf; b != NULL; b = b->next) {
+        size = nxt_buf_mem_used_size(&b->mem);
+
+        n = nxt_file_write(&file, b->mem.pos, size, 0);
+
+        if (nxt_slow_path(n != size)) {
+            nxt_file_close(task, &file);
+            (void) nxt_file_delete(file.name);
+            goto error;
+        }
+    }
+
+    nxt_file_close(task, &file);
+
+    ret = nxt_file_rename(file.name, (nxt_file_name_t *) rt->conf);
+
+    if (nxt_fast_path(ret == NXT_OK)) {
+        return;
+    }
+
+error:
+
+    nxt_log(task, NXT_LOG_ALERT, "failed to store current configuration");
+}
diff --git a/src/nxt_port.h b/src/nxt_port.h
index 78228ff7..a338a8c4 100644
--- a/src/nxt_port.h
+++ b/src/nxt_port.h
@@ -25,6 +25,7 @@ typedef enum {
     _NXT_PORT_MSG_START_WORKER,
     _NXT_PORT_MSG_SOCKET,
     _NXT_PORT_MSG_MODULES,
+    _NXT_PORT_MSG_CONF_STORE,
     _NXT_PORT_MSG_RPC_READY,
     _NXT_PORT_MSG_RPC_ERROR,
 
@@ -43,6 +44,7 @@ typedef enum {
                                   NXT_PORT_MSG_LAST,
     NXT_PORT_MSG_SOCKET         = _NXT_PORT_MSG_SOCKET | NXT_PORT_MSG_LAST,
     NXT_PORT_MSG_MODULES        = _NXT_PORT_MSG_MODULES | NXT_PORT_MSG_LAST,
+    NXT_PORT_MSG_CONF_STORE     = _NXT_PORT_MSG_CONF_STORE | NXT_PORT_MSG_LAST,
     NXT_PORT_MSG_RPC_READY      = _NXT_PORT_MSG_RPC_READY,
     NXT_PORT_MSG_RPC_READY_LAST = _NXT_PORT_MSG_RPC_READY | NXT_PORT_MSG_LAST,
     NXT_PORT_MSG_RPC_ERROR      = _NXT_PORT_MSG_RPC_ERROR | NXT_PORT_MSG_LAST,
diff --git a/src/nxt_runtime.c b/src/nxt_runtime.c
index f569f3f2..ac0775ee 100644
--- a/src/nxt_runtime.c
+++ b/src/nxt_runtime.c
@@ -722,6 +722,7 @@ nxt_runtime_conf_init(nxt_task_t *task, nxt_runtime_t *rt)
     rt->pid = NXT_PID;
     rt->log = NXT_LOG;
     rt->modules = NXT_MODULES;
+    rt->state = NXT_STATE;
     rt->control = NXT_CONTROL_SOCK;
 
     if (nxt_runtime_conf_read_cmd(task, rt) != NXT_OK) {
@@ -771,6 +772,28 @@ nxt_runtime_conf_init(nxt_task_t *task, nxt_runtime_t *rt)
 
     rt->modules = (char *) file_name.start;
 
+    slash = "";
+    n = nxt_strlen(rt->state);
+
+    if (n > 1 && rt->state[n - 1] != '/') {
+        slash = "/";
+    }
+
+    ret = nxt_file_name_create(rt->mem_pool, &file_name, "%s%sconf.json%Z",
+                               rt->state, slash);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+    rt->conf = (char *) file_name.start;
+
+    ret = nxt_file_name_create(rt->mem_pool, &file_name, "%s.tmp%Z", rt->conf);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+    rt->conf_tmp = (char *) file_name.start;
+
     control.length = nxt_strlen(rt->control);
     control.start = (u_char *) rt->control;
 
@@ -808,6 +831,7 @@ nxt_runtime_conf_read_cmd(nxt_task_t *task, nxt_runtime_t *rt)
     static const char  no_log[] = "option \"--log\" requires filename\n";
     static const char  no_modules[] =
                        "option \"--modules\" requires directory\n";
+    static const char  no_state[] = "option \"--state\" requires directory\n";
 
     static const char  help[] =
         "\n"
@@ -829,6 +853,9 @@ nxt_runtime_conf_read_cmd(nxt_task_t *task, nxt_runtime_t *rt)
         "  --modules DIRECTORY  set modules directory name\n"
         "                       default: \"" NXT_MODULES "\"\n"
         "\n"
+        "  --state DIRECTORY    set state directory name\n"
+        "                       default: \"" NXT_STATE "\"\n"
+        "\n"
         "  --user USER          set non-privileged processes to run"
                                 " as specified user\n"
         "                       default: \"" NXT_USER "\"\n"
@@ -938,6 +965,19 @@ nxt_runtime_conf_read_cmd(nxt_task_t *task, nxt_runtime_t *rt)
             continue;
         }
 
+        if (nxt_strcmp(p, "--state") == 0) {
+            if (*argv == NULL) {
+                write(STDERR_FILENO, no_state, sizeof(no_state) - 1);
+                return NXT_ERROR;
+            }
+
+            p = *argv++;
+
+            rt->state = p;
+
+            continue;
+        }
+
         if (nxt_strcmp(p, "--no-daemon") == 0) {
             rt->daemon = 0;
             continue;
diff --git a/src/nxt_runtime.h b/src/nxt_runtime.h
index b491002e..d0decfd2 100644
--- a/src/nxt_runtime.h
+++ b/src/nxt_runtime.h
@@ -58,6 +58,9 @@ struct nxt_runtime_s {
     const char             *pid;
     const char             *log;
     const char             *modules;
+    const char             *state;
+    const char             *conf;
+    const char             *conf_tmp;
     const char             *control;
 
     nxt_queue_t            engines;            /* of nxt_event_engine_t */
diff --git a/src/nxt_worker_process.c b/src/nxt_worker_process.c
index 6804f8ab..1a7d0c53 100644
--- a/src/nxt_worker_process.c
+++ b/src/nxt_worker_process.c
@@ -31,6 +31,7 @@ nxt_port_handler_t  nxt_worker_process_port_handlers[] = {
     NULL, /* NXT_PORT_MSG_START_WORKER */
     NULL, /* NXT_PORT_MSG_SOCKET       */
     NULL, /* NXT_PORT_MSG_MODULES      */
+    NULL, /* NXT_PORT_MSG_CONF_STORE   */
     nxt_port_rpc_handler,
     nxt_port_rpc_handler,
 };
@@ -47,6 +48,7 @@ nxt_port_handler_t  nxt_app_process_port_handlers[] = {
     NULL, /* NXT_PORT_MSG_START_WORKER */
     NULL, /* NXT_PORT_MSG_SOCKET       */
     NULL, /* NXT_PORT_MSG_MODULES      */
+    NULL, /* NXT_PORT_MSG_CONF_STORE   */
     nxt_port_rpc_handler,
     nxt_port_rpc_handler,
 };
@@ -63,6 +65,7 @@ nxt_port_handler_t  nxt_router_process_port_handlers[] = {
     NULL, /* NXT_PORT_MSG_START_WORKER */
     NULL, /* NXT_PORT_MSG_SOCKET       */
     NULL, /* NXT_PORT_MSG_MODULES      */
+    NULL, /* NXT_PORT_MSG_CONF_STORE   */
     nxt_port_rpc_handler,
     nxt_port_rpc_handler,
 };
@@ -79,6 +82,7 @@ nxt_port_handler_t  nxt_discovery_process_port_handlers[] = {
     NULL, /* NXT_PORT_MSG_START_WORKER */
     NULL, /* NXT_PORT_MSG_SOCKET       */
     NULL, /* NXT_PORT_MSG_MODULES      */
+    NULL, /* NXT_PORT_MSG_CONF_STORE   */
     nxt_port_rpc_handler,
     nxt_port_rpc_handler,
 };