Main Page
Modules
Data Structures
Files
File List
Globals
All
Data Structures
Files
Functions
Variables
Typedefs
Enumerations
Enumerator
Friends
Macros
Groups
Pages
aerospike
aerospike_scan.h
Go to the documentation of this file.
1
/*
2
* Copyright 2008-2014 Aerospike, Inc.
3
*
4
* Portions may be licensed to Aerospike, Inc. under one or more contributor
5
* license agreements.
6
*
7
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
8
* use this file except in compliance with the License. You may obtain a copy of
9
* the License at http://www.apache.org/licenses/LICENSE-2.0
10
*
11
* Unless required by applicable law or agreed to in writing, software
12
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
13
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
14
* License for the specific language governing permissions and limitations under
15
* the License.
16
*/
17
#pragma once
18
19
/**
20
* @defgroup scan_operations Scan Operations
21
* @ingroup client_operations
22
*
23
* Aerospike Scan Operations provide the ability to scan all record of a
24
* namespace and set in an Aerospike database.
25
*
26
* ## Usage
27
*
28
* Before you can execute a scan, you first need to define a scan using
29
* as_scan. See as_scan for details on defining scans.
30
*
31
* Once you have a scan defined, then you can execute the scan
32
* using either:
33
*
34
* - aerospike_scan_foreach() — Execute a scan on the database, then process
35
* the results.
36
* - aerospike_scan_background() — Send a scan to the database, and not wait
37
* for completed. The scan is given an id, which can be used to query the
38
* scan status.
39
*
40
* When aerospike_scan_foreach() is executed, it will process the results
41
* and create records on the stack. Because the records are on the stack,
42
* they will only be available within the context of the callback function.
43
*
44
* When aerospike_scan_background() is executed, the client will not wait for
45
* results from the database. Instead, the client will be given a scan_id,
46
* which can be used to query the scan status on the database via
47
* aerospike_scan_info().
48
*
49
* ## Walk-through
50
*
51
* First, we build a scan using as_scan. The scan will be on the "test"
52
* namespace and "demo" set. We will select only bins "a" and "b" to be returned
53
* for each record.
54
*
55
* ~~~~~~~~~~{.c}
56
* as_scan scan;
57
* as_scan_init(&scan, "test", "demo");
58
*
59
* as_scan_select_inita(&scan, 2);
60
* as_scan_select(&scan, "a");
61
* as_scan_select(&scan, "B");
62
* ~~~~~~~~~~
63
*
64
* Now that we have a scan defined, we want to execute it using
65
* aerospike_scan_foreach().
66
*
67
* ~~~~~~~~~~{.c}
68
* if ( aerospike_scan_foreach(&as, &err, NULL, &scan, callback, NULL) != AEROSPIKE_OK ) {
69
* fprintf(stderr, "error(%d) %s at [%s:%d]", err.code, err.message, err.file, err.line);
70
* }
71
* ~~~~~~~~~~
72
*
73
* The callback provided to the function above is implemented as:
74
*
75
* ~~~~~~~~~~{.c}
76
* bool callback(const as_val * val, void * udata) {
77
* as_record * rec = as_record_fromval(val);
78
* if ( !rec ) return false;
79
* fprintf("record contains %d bins", as_record_numbins(rec));
80
* return true;
81
* }
82
* ~~~~~~~~~~
83
*
84
* An as_scan is simply a scan definition, so it does not contain any state,
85
* allowing it to be reused for multiple scan operations.
86
*
87
* When you are finished with the scan, you should destroy the resources
88
* allocated to it:
89
*
90
* ~~~~~~~~~~{.c}
91
* as_scan_destroy(&scan);
92
* ~~~~~~~~~~
93
*/
94
95
#include <
aerospike/aerospike.h
>
96
#include <
aerospike/as_error.h
>
97
#include <
aerospike/as_policy.h
>
98
#include <
aerospike/as_scan.h
>
99
#include <
aerospike/as_status.h
>
100
#include <
aerospike/as_val.h
>
101
102
/******************************************************************************
103
* TYPES
104
*****************************************************************************/
105
106
/**
107
* This callback will be called for each value or record returned from
108
* a scan.
109
*
110
* The following functions accept the callback:
111
* - aerospike_scan_foreach()
112
* - aerospike_scan_node_foreach()
113
*
114
* ~~~~~~~~~~{.c}
115
* bool my_callback(const as_val * val, void * udata) {
116
* return true;
117
* }
118
* ~~~~~~~~~~
119
*
120
* @param val The value received from the query.
121
* @param udata User-data provided to the calling function.
122
*
123
* @return `true` to continue to the next value. Otherwise, iteration will end.
124
*
125
* @ingroup scan_operations
126
*/
127
typedef
bool (*
aerospike_scan_foreach_callback
)(
const
as_val
* val,
void
* udata);
128
129
/******************************************************************************
130
* FUNCTIONS
131
*****************************************************************************/
132
133
/**
134
* Scan the records in the specified namespace and set in the cluster.
135
*
136
* Scan will be run in the background by a thread on client side.
137
* No callback will be called in this case.
138
*
139
* ~~~~~~~~~~{.c}
140
* as_scan scan;
141
* as_scan_init(&scan, "test", "demo");
142
*
143
* uint64_t scanid = 0;
144
*
145
* if ( aerospike_scan_background(&as, &err, NULL, &scan, &scanid) != AEROSPIKE_OK ) {
146
* fprintf(stderr, "error(%d) %s at [%s:%d]", err.code, err.message, err.file, err.line);
147
* }
148
* else {
149
* printf("Running background scan job: %ll", scanid);
150
* }
151
*
152
* as_scan_destroy(&scan);
153
* ~~~~~~~~~~
154
*
155
* The scanid can be used to query the status of the scan running in the
156
* database via aerospike_scan_info().
157
*
158
* @param as The aerospike instance to use for this operation.
159
* @param err The as_error to be populated if an error occurs.
160
* @param policy The policy to use for this operation. If NULL, then the default policy will be used.
161
* @param scan The scan to execute against the cluster.
162
* @param scan_id The id for the scan job, which can be used for querying the status of the scan.
163
*
164
* @return AEROSPIKE_OK on success. Otherwise an error occurred.
165
*
166
* @ingroup scan_operations
167
*/
168
as_status
aerospike_scan_background
(
169
aerospike
* as,
as_error
* err,
const
as_policy_scan
* policy,
170
const
as_scan
* scan, uint64_t * scan_id
171
);
172
173
/**
174
* Wait for a background scan to be completed by servers.
175
*
176
* ~~~~~~~~~~{.c}
177
* uint64_t scan_id = 1234;
178
* aerospike_scan_wait(&as, &err, NULL, scan_id, 0);
179
* ~~~~~~~~~~
180
*
181
* @param as The aerospike instance to use for this operation.
182
* @param err The as_error to be populated if an error occurs.
183
* @param policy The policy to use for this operation. If NULL, then the default policy will be used.
184
* @param scan_id The id for the scan job.
185
* @param interval_ms The polling interval in milliseconds. If zero, 1000 ms is used.
186
*
187
* @return AEROSPIKE_OK on success. Otherwise an error occurred.
188
*/
189
as_status
aerospike_scan_wait
(
190
aerospike
* as,
as_error
* err,
const
as_policy_info
* policy,
191
uint64_t scan_id, uint32_t interval_ms
192
);
193
194
/**
195
* Check the progress of a background scan running on the database. The status
196
* of the scan running on the datatabse will be populated into an as_scan_info.
197
*
198
* ~~~~~~~~~~{.c}
199
* uint64_t scan_id = 1234;
200
* as_scan_info scan_info;
201
*
202
* if ( aerospike_scan_info(&as, &err, NULL, &scan, scan_id, &scan_info) != AEROSPIKE_OK ) {
203
* fprintf(stderr, "error(%d) %s at [%s:%d]", err.code, err.message, err.file, err.line);
204
* }
205
* else {
206
* printf("Scan id=%ll, status=%d percent=%d", scan_id, scan_info.status, scan_info.progress_pct);
207
* }
208
* ~~~~~~~~~~
209
*
210
*
211
* @param as The aerospike instance to use for this operation.
212
* @param err The as_error to be populated if an error occurs.
213
* @param policy The policy to use for this operation. If NULL, then the default policy will be used.
214
* @param scan_id The id for the scan job to check the status of.
215
* @param info Information about this scan, to be populated by this operation.
216
*
217
* @return AEROSPIKE_OK on success. Otherwise an error occurred.
218
*
219
* @ingroup scan_operations
220
*/
221
as_status
aerospike_scan_info
(
222
aerospike
* as,
as_error
* err,
const
as_policy_info
* policy,
223
uint64_t scan_id,
as_scan_info
* info
224
);
225
226
/**
227
* Scan the records in the specified namespace and set in the cluster.
228
*
229
* Call the callback function for each record scanned. When all records have
230
* been scanned, then callback will be called with a NULL value for the record.
231
*
232
* ~~~~~~~~~~{.c}
233
* as_scan scan;
234
* as_scan_init(&scan, "test", "demo");
235
*
236
* if ( aerospike_scan_foreach(&as, &err, NULL, &scan, callback, NULL) != AEROSPIKE_OK ) {
237
* fprintf(stderr, "error(%d) %s at [%s:%d]", err.code, err.message, err.file, err.line);
238
* }
239
*
240
* as_scan_destroy(&scan);
241
* ~~~~~~~~~~
242
*
243
*
244
* @param as The aerospike instance to use for this operation.
245
* @param err The as_error to be populated if an error occurs.
246
* @param policy The policy to use for this operation. If NULL, then the default policy will be used.
247
* @param scan The scan to execute against the cluster.
248
* @param callback The function to be called for each record scanned.
249
* @param udata User-data to be passed to the callback.
250
*
251
* @return AEROSPIKE_OK on success. Otherwise an error occurred.
252
*
253
* @ingroup scan_operations
254
*/
255
as_status
aerospike_scan_foreach
(
256
aerospike
* as,
as_error
* err,
const
as_policy_scan
* policy,
257
const
as_scan
* scan,
258
aerospike_scan_foreach_callback
callback,
void
* udata
259
);