1 files changed, 106 insertions, 0 deletions
diff --git a/src/mongo/db/pipeline/document_source_match.cpp b/src/mongo/db/pipeline/document_source_match.cpp
new file mode 100644
index 00000000000..c444cec3abe
--- /dev/null
+++ b/src/mongo/db/pipeline/document_source_match.cpp
@@ -0,0 +1,106 @@
+/**
+*    Copyright (C) 2011 10gen Inc.
+*
+*    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 "db/pipeline/document_source.h"
+
+#include "db/jsobj.h"
+#include "db/matcher.h"
+#include "db/pipeline/document.h"
+#include "db/pipeline/expression.h"
+
+namespace mongo {
+
+    const char DocumentSourceMatch::matchName[] = "$match";
+
+    DocumentSourceMatch::~DocumentSourceMatch() {
+    }
+
+    const char *DocumentSourceMatch::getSourceName() const {
+        return matchName;
+    }
+
+    void DocumentSourceMatch::sourceToBson(
+        BSONObjBuilder *pBuilder, bool explain) const {
+        const BSONObj *pQuery = matcher.getQuery();
+        pBuilder->append(matchName, *pQuery);
+    }
+
+    bool DocumentSourceMatch::accept(
+        const intrusive_ptr<Document> &pDocument) const {
+
+        /*
+          The matcher only takes BSON documents, so we have to make one.
+
+          LATER
+          We could optimize this by making a document with only the
+          fields referenced by the Matcher.  We could do this by looking inside
+          the Matcher's BSON before it is created, and recording those.  The
+          easiest implementation might be to hold onto an ExpressionDocument
+          in here, and give that pDocument to create the created subset of
+          fields, and then convert that instead.
+        */
+        BSONObjBuilder objBuilder;
+        pDocument->toBson(&objBuilder);
+        BSONObj obj(objBuilder.done());
+
+        return matcher.matches(obj);
+    }
+
+    static void uassertNoDisallowedClauses(BSONObj query) {
+        BSONForEach(e, query) {
+            // can't use the Matcher API because this would segfault the constructor
+            uassert(16395, "$where is not allowed inside of a $match aggregation expression",
+                    ! str::equals(e.fieldName(), "$where"));
+            // geo breaks if it is not the first portion of the pipline
+            uassert(16424, "$near is not allowed inside of a $match aggregation expression",
+                    ! str::equals(e.fieldName(), "$near"));
+            uassert(16425, "$within is not allowed inside of a $match aggregation expression",
+                    ! str::equals(e.fieldName(), "$within"));
+            uassert(16426, "$nearSphere is not allowed inside of a $match aggregation expression",
+                    ! str::equals(e.fieldName(), "$nearSphere"));
+            if (e.isABSONObj())
+                uassertNoDisallowedClauses(e.Obj());
+        }
+    }
+
+    intrusive_ptr<DocumentSource> DocumentSourceMatch::createFromBson(
+        BSONElement *pBsonElement,
+        const intrusive_ptr<ExpressionContext> &pExpCtx) {
+        uassert(15959, "the match filter must be an expression in an object",
+                pBsonElement->type() == Object);
+
+        uassertNoDisallowedClauses(pBsonElement->Obj());
+
+        intrusive_ptr<DocumentSourceMatch> pMatcher(
+            new DocumentSourceMatch(pBsonElement->Obj(), pExpCtx));
+
+        return pMatcher;
+    }
+
+    void DocumentSourceMatch::toMatcherBson(BSONObjBuilder *pBuilder) const {
+        const BSONObj *pQuery = matcher.getQuery();
+        pBuilder->appendElements(*pQuery);
+    }
+
+    DocumentSourceMatch::DocumentSourceMatch(
+        const BSONObj &query,
+        const intrusive_ptr<ExpressionContext> &pExpCtx):
+        DocumentSourceFilterBase(pExpCtx),
+        matcher(query) {
+    }
+}