Use 'anyOf' instead of 'oneOf' to fix nested Maybe's

proda-ai · Dec 17, 2023 · 0c8ca8b · 0c8ca8b
1 parent 6f4a07a
commit 0c8ca8b
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Showing 4 changed files with 8 additions and 4 deletions.
diff --git a/src/Data/OpenApi/Internal/Schema.hs b/src/Data/OpenApi/Internal/Schema.hs
@@ -24,7 +24,7 @@ module Data.OpenApi.Internal.Schema where
 import Prelude ()
 import Prelude.Compat
 
-import Control.Lens hiding (allOf)
+import Control.Lens hiding (allOf, anyOf)
 import Data.Data.Lens (template)
 
 import Control.Applicative ((<|>))
@@ -626,7 +626,8 @@ instance (Typeable (Fixed a), HasResolution a) => ToSchema (Fixed a) where decla
 instance ToSchema a => ToSchema (Maybe a) where
   declareNamedSchema _ = do
     ref <- declareSchemaRef (Proxy @a)
-    pure $ unnamed $ mempty & oneOf ?~ [Inline $ mempty & type_ ?~ OpenApiNull, ref]
+    -- NB: using 'oneOf' goes wrong for nested Maybe's as both subschemas match 'null'.
+    pure $ unnamed $ mempty & anyOf ?~ [Inline $ mempty & type_ ?~ OpenApiNull, ref]
 
 instance (ToSchema a, ToSchema b) => ToSchema (Either a b) where
   -- To match Aeson instance

diff --git a/src/Data/OpenApi/Schema/Generator.hs b/src/Data/OpenApi/Schema/Generator.hs
@@ -34,6 +34,8 @@ schemaGen _ schema
     | Just cases <- schema  ^. enum_  = elements cases
 schemaGen defns schema
     | Just variants <- schema ^. oneOf = schemaGen defns =<< elements (dereference defns <$> variants)
+schemaGen defns schema
+    | Just variants <- schema ^. anyOf = schemaGen defns =<< elements (dereference defns <$> variants)
 schemaGen defns schema =
     case schema ^. type_ of
       Nothing ->

diff --git a/test/Data/OpenApi/CommonTestTypes.hs b/test/Data/OpenApi/CommonTestTypes.hs
@@ -207,7 +207,7 @@ personSchemaJSON = [aesonQQ|
       "phone":  { "type": "integer" },
       "email":
         {
-          "oneOf" :
+          "anyOf" :
             [
               { "type" : "null" },
               { "type": "string" }
@@ -876,7 +876,7 @@ singleMaybeFieldSchemaJSON = [aesonQQ|
     {
       "singleMaybeField":
         {
-          "oneOf" :
+          "anyOf" :
             [
               { "type" : "null" },
               { "type": "string" }

diff --git a/test/Data/OpenApi/Schema/ValidationSpec.hs b/test/Data/OpenApi/Schema/ValidationSpec.hs
@@ -86,6 +86,7 @@ spec = do
     prop "TL.Text" $ shouldValidate (Proxy :: Proxy TL.Text)
     prop "[String]" $ shouldValidate (Proxy :: Proxy [String])
     prop "(Maybe [Int])" $ shouldValidate (Proxy :: Proxy (Maybe [Int]))
+    prop "(Maybe (Maybe Int))" $ shouldValidate (Proxy :: Proxy (Maybe (Maybe Int)))
     prop "(IntMap String)" $ shouldValidate (Proxy :: Proxy (IntMap String))
     prop "(Set Bool)" $ shouldValidate (Proxy :: Proxy (Set Bool))
     prop "(NonEmpty Bool)" $ shouldValidate (Proxy :: Proxy (NonEmpty Bool))