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 * A data-point describes a datum at a certain point of time.
41 */
42 typedef struct {
43 sdb_time_t timestamp;
44 double value;
45 } sdb_data_point_t;
47 /*
48 * A timeseries describes one or more sequences of data-points. Multiple
49 * sequences will have a name each and share the same start and end times and
50 * number of data points.
51 *
52 * Start and end times may diverge slightly from the requested start and end
53 * times depending on the resolution available in the backend data-store.
54 */
55 typedef struct {
56 sdb_time_t start;
57 sdb_time_t end;
59 sdb_data_point_t **data;
60 size_t data_len;
61 char **data_names;
62 size_t data_names_len;
63 } sdb_timeseries_t;
65 /*
66 * Time-series options specify generic parameters to be used when fetching
67 * time-series data from a data-store.
68 */
69 typedef struct {
70 sdb_time_t start;
71 sdb_time_t end;
72 } sdb_timeseries_opts_t;
74 /*
75 * sdb_timeseries_create:
76 * Allocate a time-series object, pre-populating the data_names information
77 * and allocating the data field.
78 *
79 * Returns:
80 * - a newly allocated time-series object on success
81 * - NULL else
82 */
83 sdb_timeseries_t *
84 sdb_timeseries_create(size_t data_names_len, const char * const *data_names,
85 size_t data_len);
87 /*
88 * sdb_timeseries_destroy:
89 * Destroy a time-series object, freeing all of its memory.
90 */
91 void
92 sdb_timeseries_destroy(sdb_timeseries_t *ts);
94 /*
95 * sdb_timeseries_tojson:
96 * Serialize a time-series to JSON written to the specified string buffer.
97 *
98 * Returns:
99 * - 0 on success
100 * - a negative value else
101 */
102 int
103 sdb_timeseries_tojson(sdb_timeseries_t *ts, sdb_strbuf_t *buf);
105 #ifdef __cplusplus
106 } /* extern "C" */
107 #endif
109 #endif /* ! SDB_CORE_TIMESERIES_H */
111 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */