SERVER-29571 Parse a subset of $jsonSchema into a MatchExpression.

Adds support for $jsonSchema containing only the following
JSON Schema keywords:
 - type
 - properties
 - maximum

1 files changed, 7 insertions, 4 deletions

diff --git a/src/mongo/db/matcher/expression_parser.h b/src/mongo/db/matcher/expression_parser.h
index 630f556e020..b6a7f9c21c6 100644
--- a/src/mongo/db/matcher/expression_parser.h
+++ b/src/mongo/db/matcher/expression_parser.h
@@ -82,6 +82,13 @@ public:
      */
     static StatusWith<long long> parseIntegerElementToLong(BSONElement elem);
 
+    /**
+     * Given a path over which to match, and a type alias (e.g. "long", "number", or "object"),
+     * returns the corresponding $type match expression node.
+     */
+    static StatusWith<std::unique_ptr<TypeMatchExpression>> parseTypeFromAlias(
+        StringData path, StringData typeAlias);
+
 private:
     MatchExpressionParser(const ExtensionsCallback* extensionsCallback)
         : _extensionsCallback(extensionsCallback) {}
@@ -203,10 +210,6 @@ private:
     StatusWithMatchExpression _parseInternalSchemaSingleIntegerArgument(
         const char* name, const BSONElement& elem) const;
 
-
-    // The maximum allowed depth of a query tree. Just to guard against stack overflow.
-    static const int kMaximumTreeDepth;
-
     // Performs parsing for the match extensions. We do not own this pointer - it has to live
     // as long as the parser is active.
     const ExtensionsCallback* _extensionsCallback;