finatra-jackson: add ability to bypass case class validation

Problem

The `finatra/jackson` project bundles multiple deserialization
features into `FinatraCaseClassDeserializer`. There is not a
way to bypass case class validation while still maintaining
feature compatability with the `FinatraObjectMapper`.

An example use case for this would be receiving a `POST` request
with a JSON body parsed by the `FinatraObjectMapper`, which does
some validation. This content is then stored somewhere. The
case class representations may change or introduce new validations
after that data has been stored. If that data is retrieved and
parsed via the `FinatraObjectMapper`, it will fail validation.

Solution

Introduce a `NullValidationFinatraJacksonModule` that can
be used to bypass case class validation, while retaining
the `FinatraObjectMapper`'s feature set.

Result

Users of the framework can now use the `NullValidationFinatraJacksonModule`
to optionally bypass case class validation.

Differential Revision: https://phabricator.twitter.biz/D307795

CHANGELOG.rst

@@ -7,22 +7,37 @@ Note that ``RB_ID=#`` and ``PHAB_ID=#`` correspond to associated message in comm
 Unreleased
 ----------
 
+Added
+~~~~~
+
+* finatra-jackson: Add ability to bypass case class validation using the
+  `NullValidationFinatraJacksonModule`. ``PHAB_ID=D307795``
+
+* inject-app: Add `c.t.inject.app.DtabResolution` to help users apply supplemental Dtabs added by
+  setting the dtab.add flag. This will append the supplemental Dtabs to the 
+  Dtab.base in a premain function. ``PHAB_ID=D303813``
+
+Changed
+~~~~~~~
+
 * inject-app: Move override of `com.twitter.app.App#failfastOnFlagsNotParsed` up from
   `c.t.inject.server.TwitterServer` to `com.twitter.inject.app.App` such that all Finatra-based
   applications default to this behavior. ``PHAB_ID=D307858``
 
-* inject-app|server: Fix capturing of flag ordering from Modules for adding to the App's `c.t.app.Flags`
+* inject-app|server: change capturing of flag ordering from Modules for adding to the App's `c.t.app.Flags`
   instance to match the semantics of directly calling `c.t.app.Flags#add`. Prefer `AtomicBoolean`
   instances over where we currently use mutable `Boolean` instances in `c.t.inject.app.App`, `c.t.inject.app.TestInjector`,
   and `c.t.inject.server.EmbeddedTwitterServer`. ``PHAB_ID=D306897``
 
-* inject-app: Add `c.t.inject.app.DtabResolution` to help users apply supplemental Dtabs added by
-  setting the dtab.add flag. This will append the supplemental Dtabs to the 
-  Dtab.base in a premain function. ``PHAB_ID=D303813``
-
 * finatra-examples: Update "twitter-clone" example to use `Dtabs` instead of the deprecated `resolverMap`.
   Move the "hello-world" example to "http-server". ``PHAB_ID=D303813``
 
+Fixed
+~~~~~
+
+Closed
+~~~~~~
+
 19.4.0
 ------
 

doc/src/sphinx/user-guide/json/validations.rst

@@ -49,3 +49,21 @@ Eg.,
         "nsfw: 'abc' is not a valid boolean"
       ]
     }
+
+Bypassing Validation
+--------------------
+
+You may desire to execute validation for specific case classes in certain scenarios, but bypass validation in others.
+For example, you may want to validate a `POST` request on the write path and store the JSON results somewhere, but
+bypass validating that same JSON for a `GET` request on the read path.
+
+You can create a `FinatraObjectMapper <https://github.com/twitter/finatra/blob/develop/jackson/src/main/scala/com/twitter/finatra/json/FinatraObjectMapper.scala>`__
+that will bypass validation like this:
+
+.. code:: scala
+
+    def create(injector: Injector = null): FinatraObjectMapper = {
+      val jacksonModule = NullValidationFinatraJacksonModule
+      new FinatraObjectMapper(
+        jacksonModule.provideScalaObjectMapper(injector))
+    }

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/CaseClassValidator.scala

@@ -6,7 +6,7 @@ import java.lang.annotation.Annotation
 /**
  * Trait for defining a validator that will be triggered during Case Class validation.
  */
-private[finatra] trait CaseClassValidator {
+private[json] trait CaseClassValidator {
 
   def validateField[V](
     fieldValue: V,

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/DefaultValidationProvider.scala

@@ -2,7 +2,7 @@ package com.twitter.finatra.json.internal.caseclass.validation
 
 import com.twitter.finatra.validation.ValidationMessageResolver
 
-private[finatra] object DefaultValidationProvider extends ValidationProvider {
+private[json] object DefaultValidationProvider extends ValidationProvider {
 
   override def apply(): CaseClassValidator = {
     val messageResolver = new ValidationMessageResolver

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/NullCaseClassValidator.scala

@@ -0,0 +1,18 @@
+package com.twitter.finatra.json.internal.caseclass.validation
+
+import com.twitter.finatra.validation.ValidationResult
+import java.lang.annotation.Annotation
+
+/**
+ * No-op validator, which will treat any field values as acceptable during
+ * Finatra Validation of annotations.
+ */
+private[json] object NullCaseClassValidator extends CaseClassValidator {
+
+  override def validateField[V](
+    fieldValue: V,
+    fieldValidationAnnotations: Seq[Annotation]
+  ): Seq[ValidationResult] = Seq.empty
+
+  override def validateObject(obj: Any): Seq[ValidationResult] = Seq.empty
+}

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/NullValidationProvider.scala

@@ -0,0 +1,8 @@
+package com.twitter.finatra.json.internal.caseclass.validation
+
+/**
+ * Provides a validation bypass for case class validation.
+ */
+private[json] object NullValidationProvider extends ValidationProvider {
+  override def apply(): CaseClassValidator = NullCaseClassValidator
+}

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/ValidationProvider.scala

@@ -3,7 +3,7 @@ package com.twitter.finatra.json.internal.caseclass.validation
 /**
  * Trait that defines a factory for returning a CaseClassValidator.
  */
-private[finatra] trait ValidationProvider {
+private[json] trait ValidationProvider {
 
   /**
    * Return a CaseClassValidator instance that will be used to provide validation against

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/CountryCodeValidator.scala

@@ -10,7 +10,7 @@ import com.twitter.finatra.validation.{
 }
 import java.util.Locale
 
-private[finatra] object CountryCodeValidator {
+private[json] object CountryCodeValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, value: Any) = {
 
@@ -29,7 +29,7 @@ private[finatra] object CountryCodeValidator {
   }
 }
 
-private[finatra] class CountryCodeValidator(
+private[json] class CountryCodeValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: CountryCode
 ) extends Validator[CountryCode, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/FutureTimeValidator.scala

@@ -10,7 +10,7 @@ import com.twitter.finatra.validation.{
 }
 import org.joda.time.DateTime
 
-private[finatra] object FutureTimeValidator {
+private[json] object FutureTimeValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, value: DateTime) = {
 
@@ -21,7 +21,7 @@ private[finatra] object FutureTimeValidator {
 /**
  * Validates if a datetime is in the future.
  */
-private[finatra] class FutureTimeValidator(
+private[json] class FutureTimeValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: FutureTime
 ) extends Validator[FutureTime, DateTime](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/MaxValidator.scala

@@ -8,15 +8,15 @@ import com.twitter.finatra.validation.{
   Validator
 }
 
-private[finatra] object MaxValidator {
+private[json] object MaxValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, value: Any, maxValue: Long): String = {
 
     resolver.resolve(classOf[Max], value, maxValue)
   }
 }
 
-private[finatra] class MaxValidator(
+private[json] class MaxValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: Max
 ) extends Validator[Max, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/MinValidator.scala

@@ -8,15 +8,15 @@ import com.twitter.finatra.validation.{
   Validator
 }
 
-private[finatra] object MinValidator {
+private[json] object MinValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, value: Any, minValue: Long): String = {
 
     resolver.resolve(classOf[Min], value, minValue)
   }
 }
 
-private[finatra] class MinValidator(
+private[json] class MinValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: Min
 ) extends Validator[Min, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/NotEmptyValidator.scala

@@ -9,15 +9,15 @@ import com.twitter.finatra.validation.{
   Validator
 }
 
-private[finatra] object NotEmptyValidator {
+private[json] object NotEmptyValidator {
 
   def errorMessage(resolver: ValidationMessageResolver) = {
 
     resolver.resolve(classOf[NotEmpty])
   }
 }
 
-private[finatra] class NotEmptyValidator(
+private[json] class NotEmptyValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: NotEmpty
 ) extends Validator[NotEmpty, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/OneOfValidator.scala

@@ -9,7 +9,7 @@ import com.twitter.finatra.validation.{
   Validator
 }
 
-private[finatra] object OneOfValidator {
+private[json] object OneOfValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, oneOfValues: Set[String], value: Any) = {
 
@@ -36,7 +36,7 @@ private[finatra] object OneOfValidator {
  * Validates if one or more values exist in a given set of values.  The check for existence is case-sensitive
  * by default.
  */
-private[finatra] class OneOfValidator(
+private[json] class OneOfValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: OneOf
 ) extends Validator[OneOf, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/PastTimeValidator.scala

@@ -10,7 +10,7 @@ import com.twitter.finatra.validation.{
 }
 import org.joda.time.DateTime
 
-private[finatra] object PastTimeValidator {
+private[json] object PastTimeValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, value: DateTime) = {
 
@@ -21,7 +21,7 @@ private[finatra] object PastTimeValidator {
 /**
  * Validates if a datetime is in the past.
  */
-private[finatra] class PastTimeValidator(
+private[json] class PastTimeValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: PastTime
 ) extends Validator[PastTime, DateTime](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/PatternValidator.scala

@@ -6,7 +6,7 @@ import com.twitter.finatra.validation._
 import com.twitter.util.{Return, Throw, Try}
 import scala.util.matching.Regex
 
-private[finatra] object PatternValidator {
+private[json] object PatternValidator {
   def errorMessage(resolver: ValidationMessageResolver, value: Any, regex: String): String = {
     resolver.resolve(classOf[Pattern], value, regex)
   }
@@ -19,7 +19,7 @@ private[finatra] object PatternValidator {
  *            case class ExampleRequest(@Pattern(regexp= "exampleRegex") exampleValue : String)
  *         }}}
  */
-private[finatra] class PatternValidator(
+private[json] class PatternValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: Pattern)
     extends Validator[Pattern, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/RangeValidator.scala

@@ -8,7 +8,7 @@ import com.twitter.finatra.validation.{
   Validator
 }
 
-private[finatra] object RangeValidator {
+private[json] object RangeValidator {
 
   def errorMessage(
     resolver: ValidationMessageResolver,
@@ -21,7 +21,7 @@ private[finatra] object RangeValidator {
   }
 }
 
-private[finatra] class RangeValidator(
+private[json] class RangeValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: Range
 ) extends Validator[Range, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/SizeValidator.scala

@@ -9,7 +9,7 @@ import com.twitter.finatra.validation.{
   Validator
 }
 
-private[finatra] object SizeValidator {
+private[json] object SizeValidator {
 
   def errorMessage(
     resolver: ValidationMessageResolver,
@@ -35,7 +35,7 @@ private[finatra] object SizeValidator {
   }
 }
 
-private[finatra] class SizeValidator(
+private[json] class SizeValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: Size
 ) extends Validator[Size, Any](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/TimeGranularityValidator.scala

@@ -12,7 +12,7 @@ import java.util.concurrent.TimeUnit
 import java.util.concurrent.TimeUnit._
 import org.joda.time.{DateTime, DateTimeZone}
 
-private[finatra] object TimeGranularityValidator {
+private[json] object TimeGranularityValidator {
 
   def errorMessage(
     resolver: ValidationMessageResolver,
@@ -32,7 +32,7 @@ private[finatra] object TimeGranularityValidator {
 /**
  * Validates if a given value is of a given time granularity (e.g., days, hours, seconds)
  */
-private[finatra] class TimeGranularityValidator(
+private[json] class TimeGranularityValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: TimeGranularity
 ) extends Validator[TimeGranularity, DateTime](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/internal/caseclass/validation/validators/UUIDValidator.scala

@@ -11,7 +11,7 @@ import com.twitter.finatra.validation.{
 import com.twitter.util.Try
 import java.util.{UUID => JUUID}
 
-private[finatra] object UUIDValidator {
+private[json] object UUIDValidator {
 
   def errorMessage(resolver: ValidationMessageResolver, value: String) = {
 
@@ -23,7 +23,7 @@ private[finatra] object UUIDValidator {
   }
 }
 
-private[finatra] class UUIDValidator(
+private[json] class UUIDValidator(
   validationMessageResolver: ValidationMessageResolver,
   annotation: UUID
 ) extends Validator[UUID, String](validationMessageResolver, annotation) {

jackson/src/main/scala/com/twitter/finatra/json/modules/NullValidationCaseClassModule.scala

@@ -0,0 +1,14 @@
+package com.twitter.finatra.json.modules
+
+import com.fasterxml.jackson.module.scala._
+import com.twitter.finatra.json.internal.caseclass.jackson.CaseClassDeserializers
+import com.twitter.finatra.json.internal.caseclass.validation.NullValidationProvider
+
+/**
+ * Module that supports skipping validation of Finatra validation annotations.
+ */
+private[json] object NullValidationCaseClassModule extends JacksonModule {
+  override def getModuleName = "NullValidationCaseClassModule"
+
+  this += { _.addDeserializers(new CaseClassDeserializers(NullValidationProvider)) }
+}

jackson/src/main/scala/com/twitter/finatra/json/modules/NullValidationFinatraJacksonModule.scala

@@ -0,0 +1,13 @@
+package com.twitter.finatra.json.modules
+
+/**
+ * Provides a FinatraJacksonModule that will treat all fields as acceptable during
+ * Finatra Validation of annotations.
+ */
+object NullValidationFinatraJacksonModule extends NullValidationFinatraJacksonModule
+
+class NullValidationFinatraJacksonModule extends FinatraJacksonModule {
+
+  override val finatraCaseClassModule = Some(NullValidationCaseClassModule)
+
+}