Code

store_json: Remove any memstore-specific code.
authorSebastian Harl <sh@tokkee.org>
Mon, 28 Sep 2015 20:15:41 +0000 (22:15 +0200)
committerSebastian Harl <sh@tokkee.org>
Mon, 28 Sep 2015 20:15:41 +0000 (22:15 +0200)
This will allow to further separate the JSON code from the memstore
implementation.

src/core/store-private.h
src/core/store_json.c

index f08bf1d..e851487 100644 (file)
@@ -48,6 +48,7 @@ extern "C" {
 
 struct sdb_store_obj {
        sdb_object_t super;
+#define _name super.name
 
        /* object type */
        int type;
index a2c117b..26a0854 100644 (file)
@@ -89,6 +89,28 @@ static sdb_type_t formatter_type = {
        /* destroy = */ NULL,
 };
 
+/* A generic representation of a stored object. */
+typedef struct {
+       /* identifier */
+       int type;
+       const char *name;
+
+       /* attribute value (optional) */
+       sdb_data_t *value;
+
+       /* metric's timeseries (optional)
+        * -1: unset
+        *  0: false
+        *  1: true */
+       int timeseries;
+
+       /* generic meta-data */
+       sdb_time_t last_update;
+       sdb_time_t interval;
+       size_t backends_num;
+       const char * const *backends;
+} obj_t;
+
 /*
  * private helper functions
  */
@@ -124,78 +146,78 @@ escape_string(const char *src, char *dest)
  * new object. That is, it manages context information and emit the prefix and
  * suffix of an object. */
 static int
-handle_new_object(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj)
+handle_new_object(sdb_store_json_formatter_t *f, int type)
 {
        /* first top-level object */
        if (! f->context[0]) {
-               if ((obj->type != f->type) && (obj->type != SDB_HOST)) {
+               if ((type != f->type) && (type != SDB_HOST)) {
                        sdb_log(SDB_LOG_ERR, "store: Unexpected object of type %s "
                                        "as the first element during %s JSON serialization",
-                                       SDB_STORE_TYPE_TO_NAME(obj->type),
+                                       SDB_STORE_TYPE_TO_NAME(type),
                                        SDB_STORE_TYPE_TO_NAME(f->type));
                        return -1;
                }
                if (f->flags & SDB_WANT_ARRAY)
                        sdb_strbuf_append(f->buf, "[");
                assert(f->current == 0);
-               f->context[f->current] = obj->type;
+               f->context[f->current] = type;
                return 0;
        }
 
        if ((f->context[f->current] != SDB_HOST)
-                       && (obj->type != SDB_ATTRIBUTE)) {
+                       && (type != SDB_ATTRIBUTE)) {
                /* new entry of the same type or a parent object;
                 * rewind to the right state */
                while ((f->current > 0)
-                               && (f->context[f->current] != obj->type)) {
+                               && (f->context[f->current] != type)) {
                        sdb_strbuf_append(f->buf, "}]");
                        --f->current;
                }
        }
 
-       if (obj->type == f->context[f->current]) {
+       if (type == f->context[f->current]) {
                /* new entry of the same type */
                sdb_strbuf_append(f->buf, "},");
        }
        else if ((f->context[f->current] == SDB_HOST)
-                       || (obj->type == SDB_ATTRIBUTE)) {
-               assert(obj->type != SDB_HOST);
+                       || (type == SDB_ATTRIBUTE)) {
+               assert(type != SDB_HOST);
                /* all object types may be children of a host;
                 * attributes may be children of any type */
                sdb_strbuf_append(f->buf, ", \"%ss\": [",
-                               SDB_STORE_TYPE_TO_NAME(obj->type));
+                               SDB_STORE_TYPE_TO_NAME(type));
                ++f->current;
        }
        else {
                sdb_log(SDB_LOG_ERR, "store: Unexpected object of type %s "
                                "on level %zu during JSON serialization",
-                               SDB_STORE_TYPE_TO_NAME(obj->type), f->current);
+                               SDB_STORE_TYPE_TO_NAME(type), f->current);
                return -1;
        }
 
        assert(f->current < SDB_STATIC_ARRAY_LEN(f->context));
-       f->context[f->current] = obj->type;
+       f->context[f->current] = type;
        return 0;
 } /* handle_new_object */
 
 static int
-json_emit(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj)
+json_emit(sdb_store_json_formatter_t *f, obj_t *obj)
 {
        char time_str[64];
        char interval_str[64];
-       char name[2 * strlen(SDB_OBJ(obj)->name) + 3];
+       char name[2 * strlen(obj->name) + 3];
        size_t i;
 
        assert(f && obj);
 
-       handle_new_object(f, obj);
+       handle_new_object(f, obj->type);
 
-       escape_string(SDB_OBJ(obj)->name, name);
+       escape_string(obj->name, name);
        sdb_strbuf_append(f->buf, "{\"name\": %s, ", name);
-       if (obj->type == SDB_ATTRIBUTE) {
-               char tmp[sdb_data_strlen(&ATTR(obj)->value) + 1];
+       if ((obj->type == SDB_ATTRIBUTE) && (obj->value)) {
+               char tmp[sdb_data_strlen(obj->value) + 1];
                char val[2 * sizeof(tmp) + 3];
-               if (! sdb_data_format(&ATTR(obj)->value, tmp, sizeof(tmp),
+               if (! sdb_data_format(obj->value, tmp, sizeof(tmp),
                                        SDB_DOUBLE_QUOTED))
                        snprintf(tmp, sizeof(tmp), "<error>");
 
@@ -208,8 +230,8 @@ json_emit(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj)
                else
                        sdb_strbuf_append(f->buf, "\"value\": %s, ", tmp);
        }
-       else if (obj->type == SDB_METRIC) {
-               if (METRIC(obj)->store.type != NULL)
+       else if ((obj->type == SDB_METRIC) && (obj->timeseries >= 0)) {
+               if (obj->timeseries)
                        sdb_strbuf_append(f->buf, "\"timeseries\": true, ");
                else
                        sdb_strbuf_append(f->buf, "\"timeseries\": false, ");
@@ -254,7 +276,28 @@ sdb_store_json_emit(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj)
 {
        if ((! f) || (! obj))
                return -1;
-       return json_emit(f, obj);
+
+       {
+               obj_t o = {
+                       obj->type,
+                       obj->_name,
+
+                       /* value */ NULL,
+                       /* timeseries */ -1,
+
+                       obj->last_update,
+                       obj->interval,
+                       obj->backends_num,
+                       (const char * const *)obj->backends,
+               };
+
+               if (obj->type == SDB_ATTRIBUTE)
+                       o.value = &ATTR(obj)->value;
+               if (obj->type == SDB_METRIC)
+                       o.timeseries = METRIC(obj)->store.type != NULL;
+
+               return json_emit(f, &o);
+       }
 } /* sdb_store_json_emit */
 
 int