2 * collection4 - action_instance_data_json.c
3 * Copyright (C) 2010 Florian octo Forster
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2.1 of the License, or (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 * Boston, MA 02110-1301 USA
21 * Florian octo Forster <ff at octo.it>
32 #include "action_instance_data_json.h"
35 #include "graph_instance.h"
36 #include "graph_list.h"
37 #include "utils_cgi.h"
40 #include <fcgi_stdio.h>
42 /* Expire data after one day. */
43 #define EXPIRES_SECS 86400
45 static void write_callback (__attribute__((unused)) void *ctx, /* {{{ */
46 const char *str, unsigned int len)
48 fwrite ((void *) str, /* size = */ len, /* nmemb = */ 1, stdout);
49 } /* }}} void write_callback */
51 static int param_get_resolution (dp_time_t *resolution) /* {{{ */
57 tmp = param ("resolution");
63 value = strtod (tmp, &endptr);
66 else if ((value <= 0.0) || (endptr == tmp))
69 resolution->tv_sec = (time_t) value;
70 resolution->tv_nsec = (long) ((value - ((double) resolution->tv_sec)) * 1000000000.0);
72 } /* }}} int param_get_resolution */
74 int action_instance_data_json (void) /* {{{ */
77 graph_instance_t *inst;
83 dp_time_t dp_begin = { 0, 0 };
84 dp_time_t dp_end = { 0, 0 };
85 dp_time_t dp_resolution = { 0, 0 };
87 yajl_gen_config handler_config;
91 char time_buffer[128];
94 cfg = gl_graph_get_selected ();
98 inst = inst_get_selected (cfg);
102 /* Get selected time(s) */
103 tt_begin = tt_end = tt_now = 0;
104 status = get_time_args (&tt_begin, &tt_end, &tt_now);
108 dp_begin.tv_sec = tt_begin;
109 dp_begin.tv_nsec = 0;
110 dp_end.tv_sec = tt_end;
113 dp_resolution.tv_sec = (tt_end - tt_begin) / 324;
114 param_get_resolution (&dp_resolution);
116 memset (&handler_config, 0, sizeof (handler_config));
117 handler_config.beautify = 0;
118 handler_config.indentString = " ";
120 handler = yajl_gen_alloc2 (write_callback,
122 /* alloc functions = */ NULL,
123 /* context = */ NULL);
127 printf ("Content-Type: application/json\n");
129 /* By default, permit caching until 1/1000th after the last data. If that
130 * data is in the past, assume the entire data is in the past and allow
131 * caching for one day. */
132 expires = tt_end + ((tt_end - tt_begin) / 1000);
133 if (expires < tt_now)
134 expires = tt_now + 86400;
136 status = time_to_rfc1123 (expires, time_buffer, sizeof (time_buffer));
138 printf ("Expires: %s\n"
139 "Cache-Control: public\n",
143 status = inst_data_to_json (inst,
144 dp_begin, dp_end, dp_resolution, handler);
146 yajl_gen_free (handler);
149 } /* }}} int action_instance_data_json */
151 /* vim: set sw=2 sts=2 et fdm=marker : */