(DOCS-14761): Validation failures include description

source/core/schema-validation.txt

@@ -144,21 +144,20 @@ query expression:
 
    :ref:`query operators <query-selectors>`
 
-Behavior
---------
+Behavior and Examples
+---------------------
 
 Validation occurs during updates and inserts. When you add validation to
 a collection, existing documents do not undergo validation checks until
 modification.
 
+Validation on Existing Documents
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
 To perform validation checks on existing documents, use the
 :dbcommand:`validate` command or the :method:`db.collection.validate()` 
 shell helper.
 
-
-Existing Documents
-~~~~~~~~~~~~~~~~~~
-
 The ``validationLevel`` option determines which operations MongoDB
 applies the validation rules:
 
@@ -176,7 +175,7 @@ documents:
 
 .. code-block:: json
 
-   db.contacts.insert([
+   db.contacts.insertMany([
       { "_id": 1, "name": "Anne", "phone": "+1 555 123 456", "city": "London", "status": "Complete" },
       { "_id": 2, "name": "Ivan", "city": "Vancouver" }
    ])
@@ -194,11 +193,11 @@ collection:
          properties: {
             phone: {
                bsonType: "string",
-               description: "must be a string and is required"
+               description: "phone must be a string and is required"
             },
             name: {
                bsonType: "string",
-               description: "must be a string and is required"
+               description: "name must be a string and is required"
             }
          }
       } },
@@ -230,12 +229,12 @@ validation rule we created above that requires ``name`` to be a string.
 
 .. code-block:: javascript
 
-   db.contacts.update(
+   db.contacts.updateOne(
       { _id: 1 },
       { $set: { name: 10 } }
    )
 
-   db.contacts.update(
+   db.contacts.updateOne(
       { _id: 2 },
       { $set: { name: 20 } }
    )
@@ -247,48 +246,44 @@ document did not meet the initial criteria when validation was added.
 
 .. code-block:: javascript
    :copyable: false
-   :emphasize-lines: 9-27
 
    // _id: 1
-   WriteResult({
-     "nMatched" : 0,
-     "nUpserted" : 0,
-     "nModified" : 0,
-     "writeError" : {
-       "code" : 121,
-       "errmsg" : "Document failed validation",
-       "errInfo" : {
-          "failingDocumentId" : 1,
-          "details" : {
-            "operatorName" : "$jsonSchema",
-            "schemaRulesNotSatisfied" : [
+   MongoServerError: Document failed validation
+   Additional information: {
+   failingDocumentId: 1,
+   details: {
+      operatorName: '$jsonSchema',
+      schemaRulesNotSatisfied: [
+         {
+         operatorName: 'properties',
+         propertiesNotSatisfied: [
             {
-              "operatorName" : "properties",
-              "propertiesNotSatisfied" : [
-                 {
-                 "propertyName" : "name",
-                 "details" : [
-                     {
-                       "operatorName" : "bsonType",
-                       "specifiedAs" : {
-                          "bsonType" : "string"
-                           },
-                       "reason" : "type did not match",
-                       "consideredValue" : 10,
-                       "consideredType" : "double"
-                     }
-                    ]
-                  }
-                ]
-              }
-            ]
+               propertyName: 'name',
+               description: 'name must be a string and is required',
+               details: [
+               {
+                  operatorName: 'bsonType',
+                  specifiedAs: { bsonType: 'string' },
+                  reason: 'type did not match',
+                  consideredValue: 10,
+                  consideredType: 'int'
+               }
+               ]
+            }
+         ]
          }
-        }
-      }
-   })
+      ]
+   }
+   }
 
    // _id: 2
-   WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
+   {
+      acknowledged: true,
+      insertedId: null,
+      matchedCount: 1,
+      modifiedCount: 0,
+      upsertedCount: 0
+   }
 
 To disable validation entirely, you can set ``validationLevel`` to
 ``off``.
@@ -333,16 +328,13 @@ Schema validator:
       validationAction: "warn" 
    } )
 
-With the ``warn`` :collflag:`validationAction`, MongoDB logs any
-violations but allows the insertion or update to proceed.
-
 For example, the following insert operation violates the validation rule:
 
 .. code-block:: javascript
 
    db.contacts2.insert( { name: "Amanda", status: "Updated" } )
 
-However, since the ``validationAction`` is ``warn`` only, MongoDB only
+However, since the ``validationAction`` is ``warn``, MongoDB only
 logs the validation violation message and allows the operation to
 proceed. Run the following command to view the MongoDB logs:
 
@@ -384,6 +376,83 @@ readability) contains information like this:
     \"specifiedAs\":{\"required\":[\"phone\"]},
         \"missingProperties\":[\"phone\"]}]}}}}"
 
+.. _validation-description-example:
+
+Use Title and Description Fields to Clarify Validation Rules
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. include:: /includes/fact-5.1-schema-validation-description-overview.rst
+
+Consider a ``users`` collection with the following schema validation:
+
+.. code-block:: javascript
+
+   db.runCommand( {
+      collMod: "users",
+      validator: { $jsonSchema: {
+         bsonType: "object",
+         title: "Email validation",
+         properties: {
+            email: {
+               "bsonType": "string",
+               "pattern": "^@mongodb\.com$",
+               "description": "Email address must end with '@mongodb.com'"
+            },
+         }
+      } },
+      validationLevel: "moderate"
+   } )
+
+The ``pattern`` field indicates that all ``email`` fields must
+end with ``@mongodb.com``. If you try to insert a document that
+does not match the pattern, MongoDB includes the validation
+``title`` and ``description`` in the error output:
+
+Input:
+
+.. code-block:: javascript
+
+   db.users.insertOne( { "name": "Amelia Morrison", "email": "a.morrison@nwsueicn.com" } )
+
+Output:
+
+.. code-block:: javascript
+   :copyable: false
+   :emphasize-lines: 6,13
+
+   MongoServerError: Document failed validation
+   Additional information: {
+     failingDocumentId: ObjectId("614a10bab93bbd15dd2e2eb6"),
+     details: {
+       operatorName: '$jsonSchema',
+       title: 'Email validation',
+       schemaRulesNotSatisfied: [
+         {
+           operatorName: 'properties',
+           propertiesNotSatisfied: [
+             {
+               propertyName: 'email',
+               description: "Email address must end with '@mongodb.com'",
+               details: [
+                 {
+                   operatorName: 'pattern',
+                   specifiedAs: { pattern: '^@mongodb.com$' },
+                   reason: 'regular expression did not match',
+                   consideredValue: 'a.morrison@nwsueicn.com'
+                 }
+               ]
+             }
+           ]
+         }
+       ]
+     }
+   }
+
+.. note::
+
+   The validation error output is formatted differently in the legacy
+   ``mongo`` shell.
+
 Restrictions
 ------------
 

source/includes/fact-5.1-schema-validation-description-overview.rst

@@ -0,0 +1,5 @@
+Starting in MongoDB 5.1, when a document fails :ref:`schema validation
+<schema-validation-overview>`, MongoDB includes the validation ``title``
+and ``description`` in the error response. You can use these fields to
+provide a clearer explanation of the validation when the rules
+are not immediately clear, such as when using regular expressions.

source/reference/operator/query/jsonSchema.txt

@@ -489,7 +489,10 @@ Available Keywords
    * - description
      - N/A
      - string
-     - A string that describes the schema and has no effect.
+     - A string that describes the schema and has no effect on
+       validation. Starting in MongoDB 5.1, if the ``description`` field
+       is specified, MongoDB includes the ``description`` in the error
+       output when a document fails validation.
 
 .. _jsonSchema-extension:
 

source/release-notes/5.1.txt

@@ -80,6 +80,13 @@ If the new parameter
   the :ref:`query explain plan output
   <explain-results-enhanced-execution>`.
 
+Schema Validation Errors Contain Description Field
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. include:: /includes/fact-5.1-schema-validation-description-overview.rst
+
+For an example, see :ref:`validation-description-example`.
+
 .. _5.1-rel-notes-repl-sets:
 
 Replica Sets