1 /*
2 * SysDB - src/include/core/timeseries.h
3 * Copyright (C) 2014 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_TIMESERIES_H
29 #define SDB_CORE_TIMESERIES_H 1
31 #include "sysdb.h"
32 #include "core/time.h"
33 #include "utils/strbuf.h"
35 #ifdef __cplusplus
36 extern "C" {
37 #endif
39 /*
40 * sdb_timeseries_info_t:
41 * Information about a timeseries.
42 */
43 typedef struct {
44 char **data_names;
45 size_t data_names_len;
46 } sdb_timeseries_info_t;
48 /*
49 * sdb_timeseries_info_create:
50 * Allocate a timeseries information object.
51 *
52 * Returns:
53 * - a newly allocated timeseries info object on success
54 * - NULL else
55 */
56 sdb_timeseries_info_t *
57 sdb_timeseries_info_create(size_t data_names_len, const char * const *data_names);
59 /*
60 * sdb_timeseries_info_destroy:
61 * Destroy a timeseries info object, freeing all of its memory.
62 */
63 void
64 sdb_timeseries_info_destroy(sdb_timeseries_info_t *ts_info);
66 /*
67 * A data-point describes a datum at a certain point of time.
68 */
69 typedef struct {
70 sdb_time_t timestamp;
71 double value;
72 } sdb_data_point_t;
74 /*
75 * A timeseries describes one or more sequences of data-points. Multiple
76 * sequences will have a name each and share the same start and end times and
77 * number of data points.
78 *
79 * Start and end times may diverge slightly from the requested start and end
80 * times depending on the resolution available in the backend data-store.
81 */
82 typedef struct {
83 sdb_time_t start;
84 sdb_time_t end;
86 sdb_data_point_t **data;
87 size_t data_len;
88 char **data_names;
89 size_t data_names_len;
90 } sdb_timeseries_t;
92 /*
93 * Time-series options specify generic parameters to be used when fetching
94 * time-series data from a data-store.
95 */
96 typedef struct {
97 sdb_time_t start;
98 sdb_time_t end;
99 } sdb_timeseries_opts_t;
101 /*
102 * sdb_timeseries_create:
103 * Allocate a time-series object, pre-populating the data_names information
104 * and allocating the data field.
105 *
106 * Returns:
107 * - a newly allocated time-series object on success
108 * - NULL else
109 */
110 sdb_timeseries_t *
111 sdb_timeseries_create(size_t data_names_len, const char * const *data_names,
112 size_t data_len);
114 /*
115 * sdb_timeseries_destroy:
116 * Destroy a time-series object, freeing all of its memory.
117 */
118 void
119 sdb_timeseries_destroy(sdb_timeseries_t *ts);
121 /*
122 * sdb_timeseries_tojson:
123 * Serialize a time-series to JSON written to the specified string buffer.
124 *
125 * Returns:
126 * - 0 on success
127 * - a negative value else
128 */
129 int
130 sdb_timeseries_tojson(sdb_timeseries_t *ts, sdb_strbuf_t *buf);
132 #ifdef __cplusplus
133 } /* extern "C" */
134 #endif
136 #endif /* ! SDB_CORE_TIMESERIES_H */
138 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */