1 /*
2 * SysDB - src/include/core/store.h
3 * Copyright (C) 2012-2015 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 "parser/ast.h"
36 #include "utils/strbuf.h"
38 #include <stdio.h>
40 #ifdef __cplusplus
41 extern "C" {
42 #endif
44 /*
45 * Store object types.
46 */
47 enum {
48 SDB_HOST = 1,
49 SDB_SERVICE,
50 SDB_METRIC,
52 SDB_ATTRIBUTE = 1 << 4,
54 /*
55 * Queryable fields of a stored object.
56 */
57 SDB_FIELD_NAME = 1 << 8, /* type: string */
58 SDB_FIELD_LAST_UPDATE, /* type: datetime */
59 SDB_FIELD_AGE, /* type: datetime */
60 SDB_FIELD_INTERVAL, /* type: datetime */
61 SDB_FIELD_BACKEND, /* type: array of strings */
62 SDB_FIELD_VALUE, /* attributes only; type: type of the value */
63 SDB_FIELD_TIMESERIES, /* metrics only; type: boolean */
64 };
65 #define SDB_STORE_TYPE_TO_NAME(t) \
66 (((t) == SDB_HOST) ? "host" \
67 : ((t) == SDB_SERVICE) ? "service" \
68 : ((t) == SDB_METRIC) ? "metric" \
69 : ((t) == SDB_ATTRIBUTE) ? "attribute" \
70 : ((t) == (SDB_ATTRIBUTE | SDB_HOST)) ? "host attribute" \
71 : ((t) == (SDB_ATTRIBUTE | SDB_SERVICE)) ? "service attribute" \
72 : ((t) == (SDB_ATTRIBUTE | SDB_METRIC)) ? "metric attribute" \
73 : "unknown")
75 #define SDB_FIELD_TO_NAME(f) \
76 (((f) == SDB_FIELD_NAME) ? "name" \
77 : ((f) == SDB_FIELD_LAST_UPDATE) ? "last-update" \
78 : ((f) == SDB_FIELD_AGE) ? "age" \
79 : ((f) == SDB_FIELD_INTERVAL) ? "interval" \
80 : ((f) == SDB_FIELD_BACKEND) ? "backend" \
81 : ((f) == SDB_FIELD_VALUE) ? "value" \
82 : ((f) == SDB_FIELD_TIMESERIES) ? "timeseries" \
83 : "unknown")
85 #define SDB_FIELD_TYPE(f) \
86 (((f) == SDB_FIELD_NAME) ? SDB_TYPE_STRING \
87 : ((f) == SDB_FIELD_LAST_UPDATE) ? SDB_TYPE_DATETIME \
88 : ((f) == SDB_FIELD_AGE) ? SDB_TYPE_DATETIME \
89 : ((f) == SDB_FIELD_INTERVAL) ? SDB_TYPE_DATETIME \
90 : ((f) == SDB_FIELD_BACKEND) ? (SDB_TYPE_ARRAY | SDB_TYPE_STRING) \
91 : ((f) == SDB_FIELD_VALUE) ? -1 /* unknown */ \
92 : ((f) == SDB_FIELD_TIMESERIES) ? SDB_TYPE_BOOLEAN \
93 : -1)
95 /*
96 * sdb_store_host_t represents the meta-data of a stored host object.
97 */
98 typedef struct {
99 const char *name;
101 sdb_time_t last_update;
102 sdb_time_t interval;
103 const char * const *backends;
104 size_t backends_num;
105 } sdb_store_host_t;
106 #define SDB_STORE_HOST_INIT { NULL, 0, 0, NULL, 0 }
108 /*
109 * sdb_store_service_t represents the meta-data of a stored service object.
110 */
111 typedef struct {
112 const char *hostname;
113 const char *name;
115 sdb_time_t last_update;
116 sdb_time_t interval;
117 const char * const *backends;
118 size_t backends_num;
119 } sdb_store_service_t;
120 #define SDB_STORE_SERVICE_INIT { NULL, NULL, 0, 0, NULL, 0 }
122 /*
123 * sdb_metric_store_t specifies how to access a metric's data.
124 */
125 typedef struct {
126 const char *type;
127 const char *id;
128 } sdb_metric_store_t;
130 /*
131 * sdb_store_metric_t represents the meta-data of a stored metric object.
132 */
133 typedef struct {
134 const char *hostname;
135 const char *name;
136 sdb_metric_store_t store;
138 sdb_time_t last_update;
139 sdb_time_t interval;
140 const char * const *backends;
141 size_t backends_num;
142 } sdb_store_metric_t;
143 #define SDB_STORE_METRIC_INIT { NULL, NULL, { NULL, NULL }, 0, 0, NULL, 0 }
145 /*
146 * sdb_store_attribute_t represents a stored attribute.
147 */
148 typedef struct {
149 const char *hostname; /* optional */
150 int parent_type;
151 const char *parent;
152 const char *key;
153 sdb_data_t value;
155 sdb_time_t last_update;
156 sdb_time_t interval;
157 const char * const *backends;
158 size_t backends_num;
159 } sdb_store_attribute_t;
160 #define SDB_STORE_ATTRIBUTE_INIT { NULL, 0, NULL, NULL, SDB_DATA_INIT, 0, 0, NULL, 0 }
162 /*
163 * A JSON formatter converts stored objects into the JSON format.
164 * See http://www.ietf.org/rfc/rfc4627.txt
165 *
166 * A JSON formatter object inherits from sdb_object_t and, thus, may safely be
167 * cast to a generic object.
168 */
169 struct sdb_store_json_formatter;
170 typedef struct sdb_store_json_formatter sdb_store_json_formatter_t;
172 /*
173 * A store writer describes the interface for plugins implementing a store.
174 *
175 * Any of the call-back functions shall return:
176 * - 0 on success
177 * - a positive value if the new entry is older than the currently stored
178 * entry (in this case, no update will happen)
179 * - a negative value on error
180 */
181 typedef struct {
182 /*
183 * store_host:
184 * Add/update a host in the store. If the host, identified by its
185 * canonicalized name, already exists, it will be updated according to the
186 * specified name and timestamp. Else, a new entry will be created in the
187 * store.
188 */
189 int (*store_host)(sdb_store_host_t *host, sdb_object_t *user_data);
191 /*
192 * store_service:
193 * Add/update a service in the store. If the service, identified by its
194 * name, already exists for the specified host, it will be updated
195 * according to the specified name and timestamp. If the referenced host
196 * does not exist, an error will be reported. Else, a new entry will be
197 * created in the store.
198 */
199 int (*store_service)(sdb_store_service_t *service, sdb_object_t *user_data);
201 /*
202 * store_metric:
203 * Add/update a metric in the store. If the metric, identified by its
204 * name, already exists for the specified host, it will be updated
205 * according to the specified attributes. If the referenced host does not
206 * exist, an error will be reported. Else, a new entry will be created in
207 * the store.
208 */
209 int (*store_metric)(sdb_store_metric_t *metric, sdb_object_t *user_data);
211 /*
212 * store_attribute:
213 * Add/update a host's attribute in the store. If the attribute,
214 * identified by its key, already exists for the specified host, it will
215 * be updated to the specified values. If the referenced host does not
216 * exist, an error will be reported. Else, a new entry will be created in
217 * the store.
218 */
219 int (*store_attribute)(sdb_store_attribute_t *attr, sdb_object_t *user_data);
220 } sdb_store_writer_t;
222 /*
223 * A store reader describes the interface to query a store implementation.
224 */
225 typedef struct {
226 /*
227 * prepare_query:
228 * Prepare the query described by 'ast' for execution.
229 */
230 sdb_object_t *(*prepare_query)(sdb_ast_node_t *ast,
231 sdb_strbuf_t *errbuf, sdb_object_t *user_data);
233 /*
234 * execute_query:
235 * Execute a previously prepared query. The callback may expect that only
236 * queries prepared by its respective prepare callback will be passed to
237 * this function. The query result will be passed back via the specified
238 * store writer.
239 */
240 int (*execute_query)(sdb_object_t *q,
241 sdb_store_writer_t *w, sdb_object_t *wd,
242 sdb_strbuf_t *errbuf, sdb_object_t *user_data);
243 } sdb_store_reader_t;
245 /*
246 * Flags for JSON formatting.
247 */
248 enum {
249 SDB_WANT_ARRAY = 1 << 0,
250 };
252 /*
253 * sdb_store_json_formatter:
254 * Create a JSON formatter for the specified object types writing to the
255 * specified buffer.
256 */
257 sdb_store_json_formatter_t *
258 sdb_store_json_formatter(sdb_strbuf_t *buf, int type, int flags);
260 /*
261 * sdb_store_json_finish:
262 * Finish the JSON output. This function has to be called once after emiting
263 * all objects.
264 */
265 int
266 sdb_store_json_finish(sdb_store_json_formatter_t *f);
268 /*
269 * sdb_store_json_writer:
270 * A store writer implementation that generates JSON output. It expects a
271 * store JSON formatter as its user-data argument.
272 */
273 extern sdb_store_writer_t sdb_store_json_writer;
275 #ifdef __cplusplus
276 } /* extern "C" */
277 #endif
279 #endif /* ! SDB_CORE_STORE_H */
281 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */