47 lines
1.3 KiB
C++
47 lines
1.3 KiB
C++
// tail.cpp
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/* Copyright 2009 10gen Inc.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/* example of using a tailable cursor */
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#include "../../client/dbclient.h"
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#include "../../util/goodies.h"
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using namespace mongo;
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void tail(DBClientBase& conn, const char *ns) {
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BSONElement lastId = minKey.firstElement();
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Query query = Query();
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auto_ptr<DBClientCursor> c =
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conn.query(ns, query, 0, 0, 0, QueryOption_CursorTailable);
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while( 1 ) {
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if( !c->more() ) {
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if( c->isDead() ) {
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break; // we need to requery
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}
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// all data (so far) exhausted, wait for more
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sleepsecs(1);
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continue;
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}
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BSONObj o = c->next();
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lastId = o["_id"];
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cout << o.toString() << endl;
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}
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}
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