add: config db-timezone-enabled for optional querying of timezones

To avoid repeated querying of `pg_timezone_names` every time schema
cache is reset, `Prefer: timezone` can be disabled by setting
`db-timezone-enabled = false`.

Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>

test/spec/Feature/Query/Preferences/TimezoneSpec.hs

@@ -10,9 +10,9 @@ import Test.Hspec.Wai.JSON
 import Protolude  hiding (get)
 import SpecHelper
 
-spec :: SpecWith ((), Application)
-spec =
-  describe "test Prefer: timezone" $ do
+enabledSpec :: SpecWith ((), Application)
+enabledSpec =
+  describe "test Prefer: timezone with db-timezone-enabled is true" $ do
     context "test Prefer: timezone=America/Los_Angeles" $ do
       it "should change timezone with handling=strict" $
         request methodGet "/timestamps"
@@ -60,3 +60,34 @@ spec =
           { matchStatus = 200
           , matchHeaders = [matchContentTypeJson
                            , "Preference-Applied" <:> "handling=lenient"]}
+
+
+disabledSpec :: SpecWith ((), Application)
+disabledSpec =
+  describe "test Prefer: timezone with db-timezone-enabled is false" $ do
+    context "test Prefer: timezone=America/Los_Angeles when timezone is disabled" $ do
+      it "should throw error with handling=strict" $
+        request methodGet "/timestamps"
+          [("Prefer", "handling=strict, timezone=America/Los_Angeles")]
+          ""
+          `shouldRespondWith`
+          [json|{"code":"PGRST122","details":"Invalid preferences: timezone=America/Los_Angeles","hint":null,"message":"Invalid preferences given with handling=strict"}|]
+          { matchStatus = 400 }
+
+      it "should return with default timezone without handling or with handling=lenient" $ do
+        request methodGet "/timestamps"
+          [("Prefer", "timezone=America/Los_Angeles")]
+          ""
+          `shouldRespondWith`
+          [json|[{"t":"2023-10-18T12:37:59.611+00:00"}, {"t":"2023-10-18T14:37:59.611+00:00"}, {"t":"2023-10-18T16:37:59.611+00:00"}]|]
+          { matchStatus = 200
+          , matchHeaders = [matchContentTypeJson]}
+
+        request methodGet "/timestamps"
+          [("Prefer", "handling=lenient, timezone=America/Los_Angeles")]
+          ""
+          `shouldRespondWith`
+          [json|[{"t":"2023-10-18T12:37:59.611+00:00"}, {"t":"2023-10-18T14:37:59.611+00:00"}, {"t":"2023-10-18T16:37:59.611+00:00"}]|]
+          { matchStatus = 200
+          , matchHeaders = [matchContentTypeJson
+                           , "Preference-Applied" <:> "handling=lenient"]}

test/spec/Main.hs

@@ -128,6 +128,7 @@ main = do
       unicodeApp           = appDbs testUnicodeCfg
       multipleSchemaApp    = appDbs testMultipleSchemaCfg
       ignorePrivOpenApi    = appDbs testIgnorePrivOpenApiCfg
+      timezoneDisabled     = appDbs testCfgTimezoneDisabled
 
 
   let analyze :: IO ()
@@ -157,7 +158,6 @@ main = do
         , ("Feature.Query.PlanSpec.disabledSpec"         , Feature.Query.PlanSpec.disabledSpec)
         , ("Feature.Query.Preferences.HandlingSpec"      , Feature.Query.Preferences.HandlingSpec.spec)
         , ("Feature.Query.Preferences.MaxAffectedSpec"   , Feature.Query.Preferences.MaxAffectedSpec.spec)
-        , ("Feature.Query.Preferences.TimezoneSpec"      , Feature.Query.Preferences.TimezoneSpec.spec)
         , ("Feature.Query.QuerySpec"                     , Feature.Query.QuerySpec.spec)
         , ("Feature.Query.RawOutputTypesSpec"            , Feature.Query.RawOutputTypesSpec.spec)
         , ("Feature.Query.RelatedQueriesSpec"            , Feature.Query.RelatedQueriesSpec.spec)
@@ -257,6 +257,15 @@ main = do
     parallel $ before withApp $
       describe "Feature.Query.AggregateFunctionsDisallowedSpec." Feature.Query.AggregateFunctionsSpec.disallowed
 
+    -- this test runs with db-timezone-enabled = true
+    parallel $ before withApp $
+      describe "Feature.Query.Preferences.TimezoneSpec.enabledSpec" Feature.Query.Preferences.TimezoneSpec.enabledSpec
+
+    -- this test runs with db-timezone-enabled = false
+    parallel $ before timezoneDisabled $
+      describe "Feature.Query.Preferences.TimezoneSpec.disabledSpec" Feature.Query.Preferences.TimezoneSpec.disabledSpec
+
+
     -- Note: the rollback tests can not run in parallel, because they test persistance and
     -- this results in race conditions
 

test/spec/SpecHelper.hs

@@ -132,6 +132,7 @@ baseCfg = let secret = encodeUtf8 "reallyreallyreallyreallyverysafe" in
   , configDbSchemas                 = fromList ["test"]
   , configDbConfig                  = False
   , configDbPreConfig               = Nothing
+  , configDbTimezoneEnabled         = True
   , configDbUri                     = "postgresql://"
   , configFilePath                  = Nothing
   , configJWKS                      = rightToMaybe $ parseSecret secret
@@ -254,6 +255,9 @@ testCfgServerTiming = baseCfg { configDbPlanEnabled = True }
 testCfgAggregatesEnabled :: AppConfig
 testCfgAggregatesEnabled = baseCfg { configDbAggregates = True }
 
+testCfgTimezoneDisabled :: AppConfig
+testCfgTimezoneDisabled = baseCfg { configDbTimezoneEnabled = False }
+
 analyzeTable :: Text -> IO ()
 analyzeTable tableName =
   void $ readProcess "psql" ["-U", "postgres", "--set", "ON_ERROR_STOP=1", "-a", "-c", toS $ "ANALYZE test.\"" <> tableName <> "\""] []