SERVER-23473 Add collation parameter to the mapReduce command

3 files changed, 50 insertions, 0 deletions

diff --git a/src/mongo/db/commands/mr.cpp b/src/mongo/db/commands/mr.cpp
index 155525578ee..b0898b1064a 100644
--- a/src/mongo/db/commands/mr.cpp
+++ b/src/mongo/db/commands/mr.cpp
@@ -336,6 +336,16 @@ Config::Config(const string& _dbname, const BSONObj& cmdObj) {
         else
             uassert(13609, "sort has to be blank or an Object", !s.trueValue());
 
+        BSONElement collationElt = cmdObj["collation"];
+        if (collationElt.type() == Object)
+            collation = collationElt.embeddedObjectUserCheck();
+        else
+            uassert(40082,
+                    str::stream()
+                        << "mapReduce 'collation' parameter must be of type Object but found type: "
+                        << typeName(collationElt.type()),
+                    collationElt.eoo());
+
         if (cmdObj["limit"].isNumber())
             limit = cmdObj["limit"].numberLong();
         else
diff --git a/src/mongo/db/commands/mr.h b/src/mongo/db/commands/mr.h
index 3d967438179..3237e6f7238 100644
--- a/src/mongo/db/commands/mr.h
+++ b/src/mongo/db/commands/mr.h
@@ -206,6 +206,7 @@ public:
 
     BSONObj filter;
     BSONObj sort;
+    BSONObj collation;
     long long limit;
 
     // functions
diff --git a/src/mongo/db/commands/mr_test.cpp b/src/mongo/db/commands/mr_test.cpp
index 93e90851257..d58ca5326f2 100644
--- a/src/mongo/db/commands/mr_test.cpp
+++ b/src/mongo/db/commands/mr_test.cpp
@@ -208,4 +208,43 @@ TEST(ConfigOutputOptionsTest, parseOutputOptions) {
                                   mr::Config::INMEMORY);
 }
 
+TEST(ConfigTest, ParseCollation) {
+    std::string dbname = "myDB";
+    BSONObj collation = BSON("locale"
+                             << "en_US");
+    BSONObjBuilder bob;
+    bob.append("mapReduce", "myCollection");
+    bob.appendCode("map", "function() { emit(0, 1); }");
+    bob.appendCode("reduce", "function(k, v) { return {count: 0}; }");
+    bob.append("out", "outCollection");
+    bob.append("collation", collation);
+    BSONObj cmdObj = bob.obj();
+    mr::Config config(dbname, cmdObj);
+    ASSERT_EQUALS(config.collation, collation);
+}
+
+TEST(ConfigTest, ParseNoCollation) {
+    std::string dbname = "myDB";
+    BSONObjBuilder bob;
+    bob.append("mapReduce", "myCollection");
+    bob.appendCode("map", "function() { emit(0, 1); }");
+    bob.appendCode("reduce", "function(k, v) { return {count: 0}; }");
+    bob.append("out", "outCollection");
+    BSONObj cmdObj = bob.obj();
+    mr::Config config(dbname, cmdObj);
+    ASSERT_EQUALS(config.collation, BSONObj());
+}
+
+TEST(ConfigTest, CollationNotAnObjectFailsToParse) {
+    std::string dbname = "myDB";
+    BSONObjBuilder bob;
+    bob.append("mapReduce", "myCollection");
+    bob.appendCode("map", "function() { emit(0, 1); }");
+    bob.appendCode("reduce", "function(k, v) { return {count: 0}; }");
+    bob.append("out", "outCollection");
+    bob.append("collation", "en_US");
+    BSONObj cmdObj = bob.obj();
+    ASSERT_THROWS(mr::Config(dbname, cmdObj), UserException);
+}
+
 }  // namespace