store: Added a generic JSON formatter.

[sysdb.git] / src / include / core / store.h

diff --git a/src/include/core/store.h b/src/include/core/store.h
index 2720db472f30abd4c853b7c1c805979749407f25..6dd7d1ade1ca98b952a4ce05a8b1a4f6bc21fa49 100644 (file)
--- a/src/include/core/store.h
+++ b/src/include/core/store.h
@@ -88,6 +88,13 @@ struct sdb_store_matcher;
 typedef struct sdb_store_matcher sdb_store_matcher_t;
 #define SDB_STORE_MATCHER(obj) ((sdb_store_matcher_t *)(obj))
 
+/*
+ * A JSON formatter converts a stored object into the JSON format.
+ * See http://www.ietf.org/rfc/rfc4627.txt
+ */
+struct sdb_store_json_formatter;
+typedef struct sdb_store_json_formatter sdb_store_json_formatter_t;
+
 /*
  * Queryable fields of a stored object.
  */
@@ -612,6 +619,58 @@ int
 sdb_store_host_tojson(sdb_store_obj_t *host, sdb_strbuf_t *buf,
                sdb_store_matcher_t *filter, int flags);
 
+/*
+ * sdb_store_json_formatter:
+ * Create a JSON formatter writing to the specified buffer.
+ */
+sdb_store_json_formatter_t *
+sdb_store_json_formatter(sdb_strbuf_t *buf);
+
+/*
+ * sdb_store_json_emit:
+ * Serialize a single object to JSON adding it to the string buffer associated
+ * with the formatter object. The serialized object will not include
+ * attributes or any child objects. Instead, call the function again for each
+ * of those objects. All attributes have to be emitted before any other
+ * children types. Use sdb_store_json_emit_full() to emit a full (filtered)
+ * object.
+ *
+ * Note that the output might not be valid JSON before calling
+ * sdb_store_json_finish().
+ *
+ * Returns:
+ *  - 0 on success
+ *  - a negative value else
+ */
+int
+sdb_store_json_emit(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj);
+
+/*
+ * sdb_store_json_emit_full:
+ * Serialize a single object including it's attributes and all children to
+ * JSON, adding it to the string buffer associated with the formatter object.
+ * The filter, if specified, is applied to each attribute and child object.
+ * Only matching objects will be included in the output.
+ *
+ * Note that the output might not be valid JSON before calling
+ * sdb_store_json_finish().
+ *
+ * Returns:
+ *  - 0 on success
+ *  - a negative value else
+ */
+int
+sdb_store_json_emit_full(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj,
+               sdb_store_matcher_t *filter);
+
+/*
+ * sdb_store_json_finish:
+ * Finish the JSON output. This function has to be called once after emiting
+ * all objects.
+ */
+int
+sdb_store_json_finish(sdb_store_json_formatter_t *f);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif