1 /*
2 * SysDB - src/include/core/store.h
3 * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
28 #ifndef SDB_CORE_STORE_H
29 #define SDB_CORE_STORE_H 1
31 #include "sysdb.h"
32 #include "core/object.h"
33 #include "core/data.h"
34 #include "core/time.h"
35 #include "core/timeseries.h"
36 #include "utils/strbuf.h"
38 #include <stdbool.h>
39 #include <stdio.h>
41 #ifdef __cplusplus
42 extern "C" {
43 #endif
45 /*
46 * Store object types.
47 */
48 enum {
49 SDB_HOST = 1,
50 SDB_SERVICE,
51 SDB_METRIC,
53 SDB_ATTRIBUTE = 1 << 4,
55 /*
56 * Queryable fields of a stored object.
57 */
58 SDB_FIELD_NAME = 1 << 8, /* type: string */
59 SDB_FIELD_LAST_UPDATE, /* type: datetime */
60 SDB_FIELD_AGE, /* type: datetime */
61 SDB_FIELD_INTERVAL, /* type: datetime */
62 SDB_FIELD_BACKEND, /* type: array of strings */
63 };
64 #define SDB_STORE_TYPE_TO_NAME(t) \
65 (((t) == SDB_HOST) ? "host" \
66 : ((t) == SDB_SERVICE) ? "service" \
67 : ((t) == SDB_METRIC) ? "metric" \
68 : ((t) == SDB_ATTRIBUTE) ? "attribute" \
69 : ((t) == (SDB_ATTRIBUTE | SDB_HOST)) ? "host attribute" \
70 : ((t) == (SDB_ATTRIBUTE | SDB_SERVICE)) ? "service attribute" \
71 : ((t) == (SDB_ATTRIBUTE | SDB_METRIC)) ? "metric attribute" \
72 : "unknown")
74 #define SDB_FIELD_TO_NAME(f) \
75 (((f) == SDB_FIELD_NAME) ? "name" \
76 : ((f) == SDB_FIELD_LAST_UPDATE) ? "last-update" \
77 : ((f) == SDB_FIELD_AGE) ? "age" \
78 : ((f) == SDB_FIELD_INTERVAL) ? "interval" \
79 : ((f) == SDB_FIELD_BACKEND) ? "backend" : "unknown")
81 #define SDB_FIELD_TYPE(f) \
82 (((f) == SDB_FIELD_NAME) ? SDB_TYPE_STRING \
83 : ((f) == SDB_FIELD_LAST_UPDATE) ? SDB_TYPE_DATETIME \
84 : ((f) == SDB_FIELD_AGE) ? SDB_TYPE_DATETIME \
85 : ((f) == SDB_FIELD_INTERVAL) ? SDB_TYPE_DATETIME \
86 : ((f) == SDB_FIELD_BACKEND) ? (SDB_TYPE_ARRAY | SDB_TYPE_STRING) \
87 : -1)
89 /*
90 * sdb_store_obj_t represents the super-class of any object stored in the
91 * database. It inherits from sdb_object_t and may safely be cast to a generic
92 * object to access its name.
93 */
94 struct sdb_store_obj;
95 typedef struct sdb_store_obj sdb_store_obj_t;
97 /*
98 * A metric store describes how to access a metric's data.
99 */
100 typedef struct {
101 const char *type;
102 const char *id;
103 } sdb_metric_store_t;
105 /*
106 * Expressions represent arithmetic expressions based on stored objects and
107 * their various attributes.
108 *
109 * An expression object inherits from sdb_object_t and, thus, may safely be
110 * cast to a generic object.
111 */
112 struct sdb_store_expr;
113 typedef struct sdb_store_expr sdb_store_expr_t;
114 #define SDB_STORE_EXPR(obj) ((sdb_store_expr_t *)(obj))
116 /*
117 * Store matchers may be used to lookup hosts from the store based on their
118 * various attributes. Service and attribute matchers are applied to a host's
119 * services and attributes and evaluate to true if *any* service or attribute
120 * matches.
121 *
122 * A store matcher object inherits from sdb_object_t and, thus, may safely be
123 * cast to a generic object.
124 */
125 struct sdb_store_matcher;
126 typedef struct sdb_store_matcher sdb_store_matcher_t;
127 #define SDB_STORE_MATCHER(obj) ((sdb_store_matcher_t *)(obj))
129 /*
130 * A JSON formatter converts stored objects into the JSON format.
131 * See http://www.ietf.org/rfc/rfc4627.txt
132 */
133 struct sdb_store_json_formatter;
134 typedef struct sdb_store_json_formatter sdb_store_json_formatter_t;
136 /*
137 * A store writer describes the interface for plugins implementing a store.
138 */
139 typedef struct {
140 int (*store_host)(const char *name, sdb_time_t last_update,
141 sdb_object_t *user_data);
142 int (*store_service)(const char *hostname, const char *name,
143 sdb_time_t last_update, sdb_object_t *user_data);
144 int (*store_metric)(const char *hostname, const char *name,
145 sdb_metric_store_t *store, sdb_time_t last_update,
146 sdb_object_t *user_data);
147 int (*store_attribute)(const char *hostname,
148 const char *key, const sdb_data_t *value, sdb_time_t last_update,
149 sdb_object_t *user_data);
150 int (*store_service_attr)(const char *hostname, const char *service,
151 const char *key, const sdb_data_t *value, sdb_time_t last_update,
152 sdb_object_t *user_data);
153 int (*store_metric_attr)(const char *hostname, const char *metric,
154 const char *key, const sdb_data_t *value, sdb_time_t last_update,
155 sdb_object_t *user_data);
156 } sdb_store_writer_t;
158 /*
159 * sdb_store_clear:
160 * Clear the entire store and remove all stored objects.
161 */
162 void
163 sdb_store_clear(void);
165 /*
166 * sdb_store_host:
167 * Add/update a host in the store. If the host, identified by its
168 * canonicalized name, already exists, it will be updated according to the
169 * specified name and timestamp. Else, a new entry will be created in the
170 * store. Any memory required for storing the entry will be allocated an
171 * managed by the store itself.
172 *
173 * Returns:
174 * - 0 on success
175 * - a positive value if the new entry is older than the currently stored
176 * entry (in this case, no update will happen)
177 * - a negative value on error
178 */
179 int
180 sdb_store_host(const char *name, sdb_time_t last_update);
182 /*
183 * sdb_store_has_host:
184 * sdb_store_get_host:
185 * Query the store for a host by its (canonicalized) name.
186 *
187 * sdb_store_get_host increments the ref count of the host object. The caller
188 * needs to deref it when no longer using it.
189 */
190 bool
191 sdb_store_has_host(const char *name);
193 sdb_store_obj_t *
194 sdb_store_get_host(const char *name);
196 /*
197 * sdb_store_attribute:
198 * Add/update a host's attribute in the store. If the attribute, identified by
199 * its key, already exists for the specified host, it will be updated to the
200 * specified values. If the referenced host does not exist, an error will be
201 * reported. Else, a new entry will be created in the store. Any memory
202 * required for storing the entry will be allocated and managed by the store
203 * itself.
204 *
205 * Returns:
206 * - 0 on success
207 * - a positive value if the new entry is older than the currently stored
208 * entry (in this case, no update will happen)
209 * - a negative value on error
210 */
211 int
212 sdb_store_attribute(const char *hostname,
213 const char *key, const sdb_data_t *value,
214 sdb_time_t last_update);
216 /*
217 * sdb_store_service:
218 * Add/update a service in the store. If the service, identified by its name,
219 * already exists for the specified host, it will be updated according to the
220 * specified 'service' object. If the referenced host does not exist, an error
221 * will be reported. Else, a new entry will be created in the store. Any
222 * memory required for storing the entry will be allocated an managed by the
223 * store itself.
224 *
225 * Returns:
226 * - 0 on success
227 * - a positive value if the new entry is older than the currently stored
228 * entry (in this case, no update will happen)
229 * - a negative value on error
230 */
231 int
232 sdb_store_service(const char *hostname, const char *name,
233 sdb_time_t last_update);
235 /*
236 * sdb_store_service_attr:
237 * Add/update a service's attribute in the store. If the attribute, identified
238 * by its key, already exists for the specified service, it will be updated to
239 * the specified value. If the references service (for the specified host)
240 * does not exist, an error will be reported. Any memory required for storing
241 * the entry will be allocated and managed by the store itself.
242 *
243 * Returns:
244 * - 0 on success
245 * - a positive value if the new entry is older than the currently stored
246 * entry (in this case, no update will happen)
247 * - a negative value on error
248 */
249 int
250 sdb_store_service_attr(const char *hostname, const char *service,
251 const char *key, const sdb_data_t *value, sdb_time_t last_update);
253 /*
254 * sdb_store_metric:
255 * Add/update a metric in the store. If the metric, identified by its name,
256 * already exists for the specified host, it will be updated according to the
257 * specified 'metric' object. If the referenced host does not exist, an error
258 * will be reported. Else, a new entry will be created in the store. Any
259 * memory required for storing the entry will be allocated an managed by the
260 * store itself.
261 *
262 * If specified, the metric store describes where to access the metric's data.
263 *
264 * Returns:
265 * - 0 on success
266 * - a positive value if the new entry is older than the currently stored
267 * entry (in this case, no update will happen)
268 * - a negative value on error
269 */
270 int
271 sdb_store_metric(const char *hostname, const char *name,
272 sdb_metric_store_t *store, sdb_time_t last_update);
274 /*
275 * sdb_store_metric_attr:
276 * Add/update a metric's attribute in the store. If the attribute, identified
277 * by its key, already exists for the specified metric, it will be updated to
278 * the specified value. If the references metric (for the specified host)
279 * does not exist, an error will be reported. Any memory required for storing
280 * the entry will be allocated and managed by the store itself.
281 *
282 * Returns:
283 * - 0 on success
284 * - a positive value if the new entry is older than the currently stored
285 * entry (in this case, no update will happen)
286 * - a negative value on error
287 */
288 int
289 sdb_store_metric_attr(const char *hostname, const char *metric,
290 const char *key, const sdb_data_t *value, sdb_time_t last_update);
292 /*
293 * sdb_store_fetch_timeseries:
294 * Fetch the time-series described by the specified host's metric and
295 * serialize it as JSON into the provided string buffer.
296 *
297 * Returns:
298 * - 0 on success
299 * - a negative value else
300 */
301 int
302 sdb_store_fetch_timeseries(const char *hostname, const char *metric,
303 sdb_timeseries_opts_t *opts, sdb_strbuf_t *buf);
305 /*
306 * sdb_store_get_child:
307 * Retrieve a host's child object of the specified type and name. The
308 * reference count of the child object will be incremented before returning
309 * it. The caller is responsible for releasing the object once it's no longer
310 * used.
311 *
312 * Returns:
313 * - the child object on success
314 * - NULL else
315 */
316 sdb_store_obj_t *
317 sdb_store_get_child(sdb_store_obj_t *host, int type, const char *name);
319 /*
320 * sdb_store_get_field:
321 * Get the value of a stored object's queryable field. The caller is
322 * responsible for freeing any dynamically allocated memory possibly stored in
323 * the returned value. If 'res' is NULL, the function will return whether the
324 * field exists.
325 *
326 * Note: Retrieving the backend this way is not currently supported.
327 *
328 * Returns:
329 * - 0 on success
330 * - a negative value else
331 */
332 int
333 sdb_store_get_field(sdb_store_obj_t *obj, int field, sdb_data_t *res);
335 /*
336 * sdb_store_get_attr:
337 * Get the value of a stored object's attribute. The caller is responsible for
338 * freeing any dynamically allocated memory possibly stored in the returned
339 * value. If 'res' is NULL, the function will return whether the attribute
340 * exists. If specified, only attributes matching the filter will be
341 * considered.
342 *
343 * Returns:
344 * - 0 if the attribute exists
345 * - a negative value else
346 */
347 int
348 sdb_store_get_attr(sdb_store_obj_t *obj, const char *name, sdb_data_t *res,
349 sdb_store_matcher_t *filter);
351 /*
352 * sdb_store_expr_create:
353 * Creates an arithmetic expression implementing the specified operator on the
354 * specified left and right operand.
355 *
356 * Returns:
357 * - an expression object on success
358 * - NULL else
359 */
360 sdb_store_expr_t *
361 sdb_store_expr_create(int op, sdb_store_expr_t *left, sdb_store_expr_t *right);
363 /*
364 * sdb_store_expr_typed:
365 * Creates an expression which evaluates in the context of an object's sibling
366 * as specified by the given type.
367 *
368 * Returns:
369 * - an expression object on success
370 * - NULL else
371 */
372 sdb_store_expr_t *
373 sdb_store_expr_typed(int typ, sdb_store_expr_t *expr);
375 /*
376 * sdb_store_expr_fieldvalue:
377 * Creates an expression which evaluates to the value of the specified
378 * queryable field of a stored object.
379 *
380 * Returns:
381 * - an expression object on success
382 * - NULL else
383 */
384 sdb_store_expr_t *
385 sdb_store_expr_fieldvalue(int field);
387 /*
388 * sdb_store_expr_attrvalue:
389 * Creates an expression which evaluates to the value of the specified
390 * attribute of a stored object. Evaluates to a NULL value if the attribute
391 * does not exist.
392 *
393 * Returns:
394 * - an expression object on success
395 * - NULL else
396 */
397 sdb_store_expr_t *
398 sdb_store_expr_attrvalue(const char *name);
400 /*
401 * sdb_store_expr_constvalue:
402 * Creates an expression which evaluates to the specified constant value.
403 *
404 * Returns:
405 * - an expression object on success
406 * - NULL else
407 */
408 sdb_store_expr_t *
409 sdb_store_expr_constvalue(const sdb_data_t *value);
411 /*
412 * sdb_store_expr_eval:
413 * Evaluate an expression for the specified stored object and stores the
414 * result in 'res'. The result's value will be allocated dynamically if
415 * necessary and, thus, should be free'd by the caller (e.g. using
416 * sdb_data_free_datum). The object may be NULL, in which case the expression
417 * needs to evaluate to a constant value. If specified, only objects matching
418 * the filter will be used during the evaluation.
419 *
420 * Returns:
421 * - 0 on success
422 * - a negative value else
423 */
424 int
425 sdb_store_expr_eval(sdb_store_expr_t *expr, sdb_store_obj_t *obj,
426 sdb_data_t *res, sdb_store_matcher_t *filter);
428 /*
429 * sdb_store_dis_matcher:
430 * Creates a matcher matching the disjunction (logical OR) of two matchers.
431 */
432 sdb_store_matcher_t *
433 sdb_store_dis_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
435 /*
436 * sdb_store_con_matcher:
437 * Creates a matcher matching the conjunction (logical AND) of two matchers.
438 */
439 sdb_store_matcher_t *
440 sdb_store_con_matcher(sdb_store_matcher_t *left, sdb_store_matcher_t *right);
442 /*
443 * sdb_store_inv_matcher::
444 * Creates a matcher matching the inverse (logical NOT) of a matcher.
445 */
446 sdb_store_matcher_t *
447 sdb_store_inv_matcher(sdb_store_matcher_t *m);
449 /*
450 * sdb_store_any_matcher:
451 * Creates a matcher iterating over objects of the specified type. It matches
452 * if *any* of those objects match 'm'.
453 */
454 sdb_store_matcher_t *
455 sdb_store_any_matcher(int type, sdb_store_matcher_t *m);
457 /*
458 * sdb_store_all_matcher:
459 * Creates a matcher iterating over objects of the specified type. It matches
460 * if *all* of those objects match 'm'.
461 */
462 sdb_store_matcher_t *
463 sdb_store_all_matcher(int type, sdb_store_matcher_t *m);
465 /*
466 * sdb_store_in_matcher:
467 * Creates a matcher which matches if the right value evaluates to an array
468 * value and the left value is included in that array. See sdb_data_inarray
469 * for more details.
470 */
471 sdb_store_matcher_t *
472 sdb_store_in_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
474 /*
475 * sdb_store_nin_matcher:
476 * Like sdb_store_in_matcher but matches if the left value is not included in
477 * the right value.
478 */
479 sdb_store_matcher_t *
480 sdb_store_nin_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
482 /*
483 * sdb_store_lt_matcher, sdb_store_le_matcher, sdb_store_eq_matcher,
484 * sdb_store_ge_matcher, sdb_store_gt_matcher:
485 * Create conditional matchers comparing the values of two expressions. The
486 * matcher matches if the left expression compres less than, less or equal
487 * than, equal to, not equal to, greater or equal than, or greater than the
488 * right expression.
489 */
490 sdb_store_matcher_t *
491 sdb_store_lt_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
492 sdb_store_matcher_t *
493 sdb_store_le_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
494 sdb_store_matcher_t *
495 sdb_store_eq_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
496 sdb_store_matcher_t *
497 sdb_store_ne_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
498 sdb_store_matcher_t *
499 sdb_store_ge_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
500 sdb_store_matcher_t *
501 sdb_store_gt_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
503 /*
504 * sdb_store_regex_matcher:
505 * Creates a matcher which matches the string value the left expression
506 * evaluates to against the regular expression the right expression evaluates
507 * to. The right expression may either be a constant value regular expression
508 * or string or a dynamic value evaluating to a string. In the latter case,
509 * the string is compiled to a regex every time the matcher is executed.
510 */
511 sdb_store_matcher_t *
512 sdb_store_regex_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
514 /*
515 * sdb_store_nregex_matcher:
516 * Creates a regex matcher just like sdb_store_regex_matcher except that it
517 * matches in case the regular expression does not match.
518 */
519 sdb_store_matcher_t *
520 sdb_store_nregex_matcher(sdb_store_expr_t *left, sdb_store_expr_t *right);
522 /*
523 * sdb_store_isnull_matcher:
524 * Creates a matcher matching NULL values.
525 */
526 sdb_store_matcher_t *
527 sdb_store_isnull_matcher(sdb_store_expr_t *expr);
529 /*
530 * sdb_store_isnnull_matcher:
531 * Creates a matcher matching non-NULL values.
532 */
533 sdb_store_matcher_t *
534 sdb_store_isnnull_matcher(sdb_store_expr_t *expr);
536 /*
537 * sdb_store_matcher_matches:
538 * Check whether the specified matcher matches the specified store object. If
539 * specified, the filter will be used to preselect objects for further
540 * evaluation. It is applied to any object that's used during the evaluation
541 * of the matcher. Only those objects matching the filter will be considered.
542 *
543 * Note that the filter is applied to all object types (hosts, service,
544 * metric, attribute). Thus, any object-specific matchers are mostly unsuited
545 * for this purpose and, if used, may result in unexpected behavior.
546 *
547 * Returns:
548 * - 1 if the object matches
549 * - 0 else
550 */
551 int
552 sdb_store_matcher_matches(sdb_store_matcher_t *m, sdb_store_obj_t *obj,
553 sdb_store_matcher_t *filter);
555 /*
556 * sdb_store_matcher_op_cb:
557 * Callback constructing a matcher operator.
558 */
559 typedef sdb_store_matcher_t *(*sdb_store_matcher_op_cb)
560 (sdb_store_expr_t *, sdb_store_expr_t *);
562 /*
563 * sdb_store_parse_matcher_op:
564 * Parse a matcher operator and return a constructor for the respective
565 * matcher.
566 *
567 * Returns:
568 * - matcher operator constructor on success
569 * - NULL else
570 */
571 sdb_store_matcher_op_cb
572 sdb_store_parse_matcher_op(const char *op);
574 /*
575 * sdb_store_parse_object_type:
576 * Parse the type name of a stored object.
577 *
578 * Returns:
579 * - the object type on success
580 * - a negative value else
581 */
582 int
583 sdb_store_parse_object_type(const char *name);
585 /*
586 * sdb_store_parse_object_type_plural:
587 * Parse the type name (plural) of a stored object.
588 *
589 * Returns:
590 * - the object type on success
591 * - a negative value else
592 */
593 int
594 sdb_store_parse_object_type_plural(const char *name);
596 /*
597 * sdb_store_parse_field_name:
598 * Parse the name of a stored object's queryable field.
599 *
600 * Returns:
601 * - the field id on success
602 * - a negative value else
603 */
604 int
605 sdb_store_parse_field_name(const char *name);
607 /*
608 * sdb_store_lookup_cb:
609 * Lookup callback. It is called for each matching object when looking up data
610 * in the store passing on the lookup filter and the specified user-data. The
611 * lookup aborts early if the callback returns non-zero.
612 */
613 typedef int (*sdb_store_lookup_cb)(sdb_store_obj_t *obj,
614 sdb_store_matcher_t *filter, void *user_data);
616 /*
617 * sdb_store_scan:
618 * Look up objects of the specified type in the store. The specified callback
619 * function is called for each object in the store matching 'm'. The function
620 * performs a full scan of all objects stored in the database. If specified,
621 * the filter will be used to preselect objects for further evaluation. See
622 * the description of 'sdb_store_matcher_matches' for details.
623 *
624 * Returns:
625 * - 0 on success
626 * - a negative value else
627 */
628 int
629 sdb_store_scan(int type, sdb_store_matcher_t *m, sdb_store_matcher_t *filter,
630 sdb_store_lookup_cb cb, void *user_data);
632 /*
633 * Flags for JSON formatting.
634 */
635 enum {
636 SDB_WANT_ARRAY = 1 << 0,
637 };
639 /*
640 * sdb_store_json_formatter:
641 * Create a JSON formatter for the specified object types writing to the
642 * specified buffer.
643 */
644 sdb_store_json_formatter_t *
645 sdb_store_json_formatter(sdb_strbuf_t *buf, int type, int flags);
647 /*
648 * sdb_store_json_emit:
649 * Serialize a single object to JSON adding it to the string buffer associated
650 * with the formatter object. The serialized object will not include
651 * attributes or any child objects. Instead, call the function again for each
652 * of those objects. All attributes have to be emitted before any other
653 * children types. Use sdb_store_json_emit_full() to emit a full (filtered)
654 * object.
655 *
656 * Note that the output might not be valid JSON before calling
657 * sdb_store_json_finish().
658 *
659 * Returns:
660 * - 0 on success
661 * - a negative value else
662 */
663 int
664 sdb_store_json_emit(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj);
666 /*
667 * sdb_store_json_emit_full:
668 * Serialize a single object including it's attributes and all children to
669 * JSON, adding it to the string buffer associated with the formatter object.
670 * The filter, if specified, is applied to each attribute and child object.
671 * Only matching objects will be included in the output.
672 *
673 * Note that the output might not be valid JSON before calling
674 * sdb_store_json_finish().
675 *
676 * Returns:
677 * - 0 on success
678 * - a negative value else
679 */
680 int
681 sdb_store_json_emit_full(sdb_store_json_formatter_t *f, sdb_store_obj_t *obj,
682 sdb_store_matcher_t *filter);
684 /*
685 * sdb_store_json_finish:
686 * Finish the JSON output. This function has to be called once after emiting
687 * all objects.
688 */
689 int
690 sdb_store_json_finish(sdb_store_json_formatter_t *f);
692 #ifdef __cplusplus
693 } /* extern "C" */
694 #endif
696 #endif /* ! SDB_CORE_STORE_H */
698 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */