1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
// group.cpp
/**
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "pch.h"
#include "../commands.h"
#include "../instance.h"
#include "../queryoptimizer.h"
#include "../../scripting/engine.h"
#include "../clientcursor.h"
namespace mongo {
class GroupCommand : public Command {
public:
GroupCommand() : Command("group") {}
virtual LockType locktype() const { return READ; }
virtual bool slaveOk() const { return false; }
virtual bool slaveOverrideOk() { return true; }
virtual void help( stringstream &help ) const {
help << "http://www.mongodb.org/display/DOCS/Aggregation";
}
BSONObj getKey( const BSONObj& obj , const BSONObj& keyPattern , ScriptingFunction func , double avgSize , Scope * s ) {
if ( func ) {
BSONObjBuilder b( obj.objsize() + 32 );
b.append( "0" , obj );
const BSONObj& key = b.obj();
int res = s->invoke( func , &key, 0 );
uassert( 10041 , (string)"invoke failed in $keyf: " + s->getError() , res == 0 );
int type = s->type("return");
uassert( 10042 , "return of $key has to be an object" , type == Object );
return s->getObject( "return" );
}
return obj.extractFields( keyPattern , true ).getOwned();
}
bool group( string realdbname , const string& ns , const BSONObj& query ,
BSONObj keyPattern , string keyFunctionCode , string reduceCode , const char * reduceScope ,
BSONObj initial , string finalize ,
string& errmsg , BSONObjBuilder& result ) {
auto_ptr<Scope> s = globalScriptEngine->getPooledScope( realdbname );
s->localConnect( realdbname.c_str() );
if ( reduceScope )
s->init( reduceScope );
s->setObject( "$initial" , initial , true );
s->exec( "$reduce = " + reduceCode , "reduce setup" , false , true , true , 100 );
s->exec( "$arr = [];" , "reduce setup 2" , false , true , true , 100 );
ScriptingFunction f = s->createFunction(
"function(){ "
" if ( $arr[n] == null ){ "
" next = {}; "
" Object.extend( next , $key ); "
" Object.extend( next , $initial , true ); "
" $arr[n] = next; "
" next = null; "
" } "
" $reduce( obj , $arr[n] ); "
"}" );
ScriptingFunction keyFunction = 0;
if ( keyFunctionCode.size() ) {
keyFunction = s->createFunction( keyFunctionCode.c_str() );
}
double keysize = keyPattern.objsize() * 3;
double keynum = 1;
map<BSONObj,int,BSONObjCmp> map;
list<BSONObj> blah;
shared_ptr<Cursor> cursor = NamespaceDetailsTransient::getCursor(ns.c_str() , query);
ClientCursor::CleanupPointer ccPointer;
ccPointer.reset( new ClientCursor( QueryOption_NoCursorTimeout, cursor, ns ) );
while ( cursor->ok() ) {
if ( !ccPointer->yieldSometimes( ClientCursor::MaybeCovered ) ||
!cursor->ok() ) {
break;
}
if ( ( cursor->matcher() && !cursor->matcher()->matchesCurrent( cursor.get() ) ) ||
cursor->getsetdup( cursor->currLoc() ) ) {
cursor->advance();
continue;
}
if ( !ccPointer->yieldSometimes( ClientCursor::WillNeed ) ||
!cursor->ok() ) {
break;
}
BSONObj obj = cursor->current();
cursor->advance();
BSONObj key = getKey( obj , keyPattern , keyFunction , keysize / keynum , s.get() );
keysize += key.objsize();
keynum++;
int& n = map[key];
if ( n == 0 ) {
n = map.size();
s->setObject( "$key" , key , true );
uassert( 10043 , "group() can't handle more than 20000 unique keys" , n <= 20000 );
}
s->setObject( "obj" , obj , true );
s->setNumber( "n" , n - 1 );
if ( s->invoke( f , 0, 0 , 0 , true ) ) {
throw UserException( 9010 , (string)"reduce invoke failed: " + s->getError() );
}
}
ccPointer.reset();
if (!finalize.empty()) {
s->exec( "$finalize = " + finalize , "finalize define" , false , true , true , 100 );
ScriptingFunction g = s->createFunction(
"function(){ "
" for(var i=0; i < $arr.length; i++){ "
" var ret = $finalize($arr[i]); "
" if (ret !== undefined) "
" $arr[i] = ret; "
" } "
"}" );
s->invoke( g , 0, 0 , 0 , true );
}
result.appendArray( "retval" , s->getObject( "$arr" ) );
result.append( "count" , keynum - 1 );
result.append( "keys" , (int)(map.size()) );
s->exec( "$arr = [];" , "reduce setup 2" , false , true , true , 100 );
s->gc();
return true;
}
bool run(const string& dbname, BSONObj& jsobj, int, string& errmsg, BSONObjBuilder& result, bool fromRepl ) {
if ( !globalScriptEngine ) {
errmsg = "server-side JavaScript execution is disabled";
return false;
}
/* db.$cmd.findOne( { group : <p> } ) */
const BSONObj& p = jsobj.firstElement().embeddedObjectUserCheck();
BSONObj q;
if ( p["cond"].type() == Object )
q = p["cond"].embeddedObject();
else if ( p["condition"].type() == Object )
q = p["condition"].embeddedObject();
else
q = getQuery( p );
if ( p["ns"].type() != String ) {
errmsg = "ns has to be set";
return false;
}
string ns = dbname + "." + p["ns"].String();
BSONObj key;
string keyf;
if ( p["key"].type() == Object ) {
key = p["key"].embeddedObjectUserCheck();
if ( ! p["$keyf"].eoo() ) {
errmsg = "can't have key and $keyf";
return false;
}
}
else if ( p["$keyf"].type() ) {
keyf = p["$keyf"]._asCode();
}
else {
// no key specified, will use entire object as key
}
BSONElement reduce = p["$reduce"];
if ( reduce.eoo() ) {
errmsg = "$reduce has to be set";
return false;
}
BSONElement initial = p["initial"];
if ( initial.type() != Object ) {
errmsg = "initial has to be an object";
return false;
}
string finalize;
if (p["finalize"].type())
finalize = p["finalize"]._asCode();
return group( dbname , ns , q ,
key , keyf , reduce._asCode() , reduce.type() != CodeWScope ? 0 : reduce.codeWScopeScopeData() ,
initial.embeddedObject() , finalize ,
errmsg , result );
}
} cmdGroup;
} // namespace mongo
|
