JSON output in controller.

3 files changed, 384 insertions, 14 deletions

diff --git a/src/nxt_conf.h b/src/nxt_conf.h
index 5d29419a..1d08199c 100644
--- a/src/nxt_conf.h
+++ b/src/nxt_conf.h
@@ -14,6 +14,8 @@ typedef struct nxt_conf_json_value_s  nxt_conf_json_value_t;
 
 nxt_conf_json_value_t *nxt_conf_json_parse(nxt_buf_mem_t *b,
     nxt_mem_pool_t *pool);
+nxt_buf_t *nxt_conf_json_print(nxt_conf_json_value_t *value,
+    nxt_mem_pool_t *pool);
 
 
 #endif /* _NXT_CONF_INCLUDED_ */
diff --git a/src/nxt_conf_json.c b/src/nxt_conf_json.c
index cf0190f4..109edf22 100644
--- a/src/nxt_conf_json.c
+++ b/src/nxt_conf_json.c
@@ -69,6 +69,20 @@ static u_char *nxt_conf_json_parse_number(u_char *pos, u_char *end,
     nxt_conf_json_value_t *value, nxt_mem_pool_t *pool);
 
 
+static uintptr_t nxt_conf_json_print_value(u_char *pos,
+    nxt_conf_json_value_t *value);
+static uintptr_t nxt_conf_json_print_integer(u_char *pos,
+    nxt_conf_json_value_t *value);
+static uintptr_t nxt_conf_json_print_string(u_char *pos,
+    nxt_conf_json_value_t *value);
+static uintptr_t nxt_conf_json_print_array(u_char *pos,
+    nxt_conf_json_value_t *value);
+static uintptr_t nxt_conf_json_print_object(u_char *pos,
+    nxt_conf_json_value_t *value);
+
+static uintptr_t nxt_conf_json_escape(u_char *dst, u_char *src, size_t size);
+
+
 static const nxt_lvlhsh_proto_t nxt_conf_json_object_hash_proto
     nxt_aligned(64) =
 {
@@ -774,3 +788,318 @@ nxt_conf_json_parse_number(u_char *pos, u_char *end,
 
     return NULL;
 }
+
+
+nxt_buf_t *
+nxt_conf_json_print(nxt_conf_json_value_t *value, nxt_mem_pool_t *pool)
+{
+    size_t     size;
+    nxt_buf_t  *b;
+
+    size = nxt_conf_json_print_value(NULL, value);
+
+    b = nxt_buf_mem_alloc(pool, size, 0);
+    if (nxt_slow_path(b == NULL)) {
+        return NULL;
+    }
+
+    b->mem.free = (u_char *) nxt_conf_json_print_value(b->mem.free, value);
+
+    return b;
+}
+
+
+static uintptr_t
+nxt_conf_json_print_value(u_char *pos, nxt_conf_json_value_t *value)
+{
+    static const u_char null[4] = "null";
+    static const u_char true[4] = "true";
+    static const u_char false[5] = "false";
+
+    switch (value->type) {
+
+    case NXT_CONF_JSON_NULL:
+
+        if (pos == NULL) {
+            return sizeof(null);
+        }
+
+        return (uintptr_t) nxt_cpymem(pos, null, sizeof(null));
+
+    case NXT_CONF_JSON_BOOLEAN:
+
+        if (pos == NULL) {
+            return value->u.boolean ? 4 : 5;
+        }
+
+        if (value->u.boolean) {
+            return (uintptr_t) nxt_cpymem(pos, true, sizeof(true));
+        }
+
+        return (uintptr_t) nxt_cpymem(pos, false, sizeof(false));
+
+    case NXT_CONF_JSON_INTEGER:
+        return nxt_conf_json_print_integer(pos, value);
+
+    case NXT_CONF_JSON_NUMBER:
+        /* TODO */
+        return (pos == NULL) ? 0 : (uintptr_t) pos;
+
+    case NXT_CONF_JSON_SHORT_STRING:
+    case NXT_CONF_JSON_STRING:
+        return nxt_conf_json_print_string(pos, value);
+
+    case NXT_CONF_JSON_ARRAY:
+        return nxt_conf_json_print_array(pos, value);
+
+    case NXT_CONF_JSON_OBJECT:
+        return nxt_conf_json_print_object(pos, value);
+    }
+
+    nxt_unreachable();
+
+    return (pos == NULL) ? 0 : (uintptr_t) pos;
+}
+
+
+static uintptr_t
+nxt_conf_json_print_integer(u_char *pos, nxt_conf_json_value_t *value)
+{
+    int64_t  num;
+
+    num = value->u.integer;
+
+    if (pos == NULL) {
+        num = llabs(num);
+
+        if (num <= 9999) {
+            return sizeof("-9999") - 1;
+        }
+
+        if (num <= 99999999999) {
+            return sizeof("-99999999999") - 1;
+        }
+
+        return NXT_INT64_T_LEN;
+    }
+
+    return (uintptr_t) nxt_sprintf(pos, pos + NXT_INT64_T_LEN, "%L", num);
+}
+
+
+static uintptr_t
+nxt_conf_json_print_string(u_char *pos, nxt_conf_json_value_t *value)
+{
+    size_t  len;
+    u_char  *s;
+
+    if (value->type == NXT_CONF_JSON_SHORT_STRING) {
+        len = value->u.str[0];
+        s = &value->u.str[1];
+
+    } else {
+        len = value->u.string->length;
+        s = value->u.string->start;
+    }
+
+    if (pos == NULL) {
+        return 2 + len + nxt_conf_json_escape(NULL, s, len);
+    }
+
+    *pos++ = '"';
+
+    pos = (u_char *) nxt_conf_json_escape(pos, s, len);
+
+    *pos++ = '"';
+
+    return (uintptr_t) pos;
+}
+
+
+static uintptr_t
+nxt_conf_json_print_array(u_char *pos, nxt_conf_json_value_t *value)
+{
+    size_t       len;
+    uint32_t     n;
+    nxt_array_t  *array;
+
+    array = value->u.array;
+
+    if (pos == NULL) {
+        len = 2;
+
+        value = array->elts;
+
+        for (n = 0; n < array->nelts; n++) {
+            len += nxt_conf_json_print_value(NULL, &value[n]);
+        }
+
+        return n + len;
+    }
+
+    *pos++ = '[';
+
+    if (array->nelts != 0) {
+        value = array->elts;
+
+        pos = (u_char *) nxt_conf_json_print_value(pos, &value[0]);
+
+        for (n = 1; n < array->nelts; n++) {
+            *pos++ = ',';
+            pos = (u_char *) nxt_conf_json_print_value(pos, &value[n]);
+        }
+    }
+
+    *pos++ = ']';
+
+    return (uintptr_t) pos;
+}
+
+
+static uintptr_t
+nxt_conf_json_print_object(u_char *pos, nxt_conf_json_value_t *value)
+{
+    size_t                      len;
+    nxt_lvlhsh_t                *object;
+    nxt_lvlhsh_each_t           lhe;
+    nxt_conf_json_obj_member_t  *member;
+
+    nxt_memzero(&lhe, sizeof(nxt_lvlhsh_each_t));
+
+    lhe.proto = &nxt_conf_json_object_hash_proto;
+
+    object = value->u.object;
+
+    if (pos == NULL) {
+        len = 2;
+
+        for ( ;; ) {
+            member = nxt_lvlhsh_each(object, &lhe);
+
+            if (member == NULL) {
+                break;
+            }
+
+            len += nxt_conf_json_print_string(NULL, &member->name) + 1
+                   + nxt_conf_json_print_value(NULL, &member->value) + 1;
+        }
+
+        return len;
+    }
+
+    *pos++ = '{';
+
+    member = nxt_lvlhsh_each(object, &lhe);
+
+    if (member != NULL) {
+
+        for ( ;; ) {
+            pos = (u_char *) nxt_conf_json_print_string(pos, &member->name);
+
+            *pos++ = ':';
+
+            pos = (u_char *) nxt_conf_json_print_value(pos, &member->value);
+
+            member = nxt_lvlhsh_each(object, &lhe);
+
+            if (member == NULL) {
+                break;
+            }
+
+            *pos++ = ',';
+        }
+    }
+
+    *pos++ = '}';
+
+    return (uintptr_t) pos;
+}
+
+
+static uintptr_t
+nxt_conf_json_escape(u_char *dst, u_char *src, size_t size)
+{
+    u_char  ch;
+    size_t  len;
+
+    if (dst == NULL) {
+        len = 0;
+
+        while (size) {
+            ch = *src++;
+
+            if (ch == '\\' || ch == '"') {
+                len++;
+
+            } else if (ch <= 0x1f) {
+
+                switch (ch) {
+                case '\n':
+                case '\r':
+                case '\t':
+                case '\b':
+                case '\f':
+                    len++;
+                    break;
+
+                default:
+                    len += sizeof("\\u001F") - 2;
+                }
+            }
+
+            size--;
+        }
+
+        return len;
+    }
+
+    while (size) {
+        ch = *src++;
+
+        if (ch > 0x1f) {
+
+            if (ch == '\\' || ch == '"') {
+                *dst++ = '\\';
+            }
+
+            *dst++ = ch;
+
+        } else {
+            *dst++ = '\\';
+
+            switch (ch) {
+            case '\n':
+                *dst++ = 'n';
+                break;
+
+            case '\r':
+                *dst++ = 'r';
+                break;
+
+            case '\t':
+                *dst++ = 't';
+                break;
+
+            case '\b':
+                *dst++ = 'b';
+                break;
+
+            case '\f':
+                *dst++ = 'f';
+                break;
+
+            default:
+                *dst++ = 'u'; *dst++ = '0'; *dst++ = '0';
+                *dst++ = '0' + (ch >> 4);
+
+                ch &= 0xf;
+
+                *dst++ = (ch < 10) ? ('0' + ch) : ('A' + ch - 10);
+            }
+        }
+
+        size--;
+    }
+
+    return (uintptr_t) dst;
+}
diff --git a/src/nxt_controller.c b/src/nxt_controller.c
index e4ca0669..901a8875 100644
--- a/src/nxt_controller.c
+++ b/src/nxt_controller.c
@@ -14,6 +14,8 @@
 typedef struct {
     nxt_http_request_parse_t  parser;
     size_t                    length;
+
+    nxt_conf_json_value_t     *conf;
 } nxt_controller_request_t;
 
 
@@ -41,7 +43,9 @@ static nxt_int_t nxt_controller_request_content_length(void *ctx,
 static void nxt_controller_process_request(nxt_task_t *task,
     nxt_event_conn_t *c, nxt_controller_request_t *r);
 static nxt_int_t nxt_controller_request_body_parse(nxt_task_t *task,
-    nxt_event_conn_t *c);
+    nxt_event_conn_t *c, nxt_controller_request_t *r);
+static void nxt_controller_conf_output(nxt_task_t *task, nxt_event_conn_t *c,
+    nxt_controller_request_t *r);
 
 
 static nxt_http_fields_t  nxt_controller_request_fields[] = {
@@ -513,29 +517,28 @@ static void
 nxt_controller_process_request(nxt_task_t *task, nxt_event_conn_t *c,
     nxt_controller_request_t *r)
 {
-    nxt_str_t  response;
     nxt_buf_t  *b;
 
-    static const u_char response_good[]
-        = "HTTP/1.0 200 OK\r\n\r\ndone\r\n";
+    static const nxt_str_t resp418
+        = nxt_string("HTTP/1.0 418 I'm a teapot\r\n\r\nerror\r\n");
 
-    static const u_char response_bad[]
-        = "HTTP/1.0 418 I'm a teapot\r\n\r\nerror\r\n";
+    if (nxt_controller_request_body_parse(task, c, r) != NXT_OK) {
+        goto error;
+    }
 
-    if (nxt_controller_request_body_parse(task, c) == NXT_OK) {
-        nxt_str_set(&response, response_good);
+    nxt_controller_conf_output(task, c, r);
 
-    } else {
-        nxt_str_set(&response, response_bad);
-    }
+    return;
 
-    b = nxt_buf_mem_alloc(c->mem_pool, response.length, 0);
+error:
+
+    b = nxt_buf_mem_alloc(c->mem_pool, resp418.length, 0);
     if (nxt_slow_path(b == NULL)) {
         nxt_controller_conn_close(task, c, r);
         return;
     }
 
-    b->mem.free = nxt_cpymem(b->mem.free, response.start, response.length);
+    b->mem.free = nxt_cpymem(b->mem.free, resp418.start, resp418.length);
 
     c->write = b;
     c->write_state = &nxt_controller_conn_write_state;
@@ -545,7 +548,8 @@ nxt_controller_process_request(nxt_task_t *task, nxt_event_conn_t *c,
 
 
 static nxt_int_t
-nxt_controller_request_body_parse(nxt_task_t *task, nxt_event_conn_t *c)
+nxt_controller_request_body_parse(nxt_task_t *task, nxt_event_conn_t *c,
+    nxt_controller_request_t *r)
 {
     nxt_buf_t              *b;
     nxt_conf_json_value_t  *value;
@@ -558,5 +562,40 @@ nxt_controller_request_body_parse(nxt_task_t *task, nxt_event_conn_t *c)
         return NXT_ERROR;
     }
 
+    r->conf = value;
+
     return NXT_OK;
 }
+
+
+static void
+nxt_controller_conf_output(nxt_task_t *task, nxt_event_conn_t *c,
+    nxt_controller_request_t *r)
+{
+    nxt_buf_t  *b;
+
+    static const nxt_str_t head = nxt_string("HTTP/1.0 200 OK\r\n\r\n");
+
+    b = nxt_buf_mem_alloc(c->mem_pool, head.length, 0);
+    if (nxt_slow_path(b == NULL)) {
+        nxt_controller_conn_close(task, c, r);
+        return;
+    }
+
+    b->mem.free = nxt_cpymem(b->mem.free, head.start, head.length);
+
+    c->write = b;
+
+    b = nxt_conf_json_print(r->conf, c->mem_pool);
+
+    if (b == NULL) {
+        nxt_controller_conn_close(task, c, r);
+        return;
+    }
+
+    c->write->next = b;
+    c->write_state = &nxt_controller_conn_write_state;
+
+    nxt_event_conn_write(task->thread->engine, c);
+    return;
+}