diff --git a/README.md b/README.md --- a/README.md +++ b/README.md @@ -144,3 +144,4 @@ * [PADS project](https://www.cs.princeton.edu/~dpw/papers/padsml06.pdf) is another attempt to automatically infer types to treat arbitrary data formats (not just JSON). It mixes type declarations, with parsing/printing information in order to have a consistent view of both. It does not handle automatic type inference though. * [JSON Schema generator](https://www.newtonsoft.com/jsonschema/help/html/GenerateSchema.htm) uses .NET types to generate JSON Schema instead (in opposite direction.) Similar schema generation is [used here](https://sixgun.wordpress.com/2012/02/09/using-json-net-to-generate-jsonschema/) * Microsoft Developer Network advocates use of [Data Contracts](https://docs.microsoft.com/en-us/dotnet/framework/wcf/feature-details/using-data-contracts) instead to constrain possible input data. +* [QuickType](https://github.com/quicktype/quicktype) uses [Markov chains heuristic](https://blog.quicktype.io/markov/) instead of theory diff --git a/changelog.md b/changelog.md --- a/changelog.md +++ b/changelog.md @@ -1,5 +1,9 @@ Changelog ========= + 3.1.0 Apr 2020 + * New, experimental interface for nesting + generated types by other code generators. + 3.0.5 Mar 2020 * Using package import from `run-haskell-module` by default. * Expose commonly used functions for: diff --git a/json-autotype.cabal b/json-autotype.cabal --- a/json-autotype.cabal +++ b/json-autotype.cabal @@ -4,10 +4,10 @@ -- -- see: https://github.com/sol/hpack -- --- hash: fb4adc71d7680a6ad92e8ac005c8302728f695d5a933e624e6b48ffb55d2787e +-- hash: 69c68aeb21aa0332a50089781cb19f9fb197bb8c6d7d633af4613de8aa4dd367 name: json-autotype -version: 3.0.5 +version: 3.1.0 synopsis: Automatic type declaration for JSON input data description: Generates datatype declarations with Aeson''s ''Data.Aeson.FromJSON'' . @@ -95,6 +95,7 @@ Data.Aeson.AutoType.CodeGen.ElmFormat Data.Aeson.AutoType.CodeGen.Generic Data.Aeson.AutoType.CodeGen.Haskell + Data.Aeson.AutoType.Nested Data.Aeson.AutoType.Plugin.Subtype Paths_json_autotype hs-source-dirs: diff --git a/src/Data/Aeson/AutoType/CodeGen/Haskell.hs b/src/Data/Aeson/AutoType/CodeGen/Haskell.hs --- a/src/Data/Aeson/AutoType/CodeGen/Haskell.hs +++ b/src/Data/Aeson/AutoType/CodeGen/Haskell.hs @@ -8,6 +8,9 @@ , runHaskellModule , runHaskellModuleStrict , defaultHaskellFilename + , importedModules + , requiredPackages + , generateModuleImports ) where import qualified Data.Text as Text @@ -49,21 +52,34 @@ -- It was automatically generated by `json-autotype`. module |] <> capitalize moduleName <> [src| where +|] <> generateModuleImports importedModules -import System.Exit (exitFailure, exitSuccess) -import System.IO (stderr, hPutStrLn) -import qualified Data.ByteString.Lazy.Char8 as BSL -import System.Environment (getArgs) -import Control.Monad (forM_, mzero, join) -import Control.Applicative -import Data.Aeson.AutoType.Alternative -import Data.Aeson(eitherDecode, Value(..), FromJSON(..), ToJSON(..), - pairs, - (.:), (.:?), (.=), object) -import Data.Monoid((<>)) -import Data.Text (Text) -import qualified GHC.Generics -|] +type ModuleImport = Text + +generateModuleImports :: [ModuleImport] -> Text +generateModuleImports = Text.unlines + . fmap ("import " <>) + +-- | List of packages required by modules below. +-- Keep and maintain together. +requiredPackages :: [Text] +requiredPackages = ["aeson", "json-alt", "base", "bytestring", "text"] + +-- | List of modules to import +importedModules :: [ModuleImport] +importedModules = [ + " System.Exit (exitFailure, exitSuccess)" + , " System.IO (stderr, hPutStrLn)" + , "qualified Data.ByteString.Lazy.Char8 as BSL" + , " System.Environment (getArgs)" + , " Control.Monad (forM_, mzero, join)" + , " Control.Applicative" + , " Data.Aeson.AutoType.Alternative" + , " Data.Aeson(eitherDecode, Value(..), FromJSON(..), ToJSON(..),pairs,(.:), (.:?), (.=), object)" + , " Data.Monoid((<>))" + , " Data.Text (Text)" + , "qualified GHC.Generics" + ] epilogue :: Text -> Text epilogue toplevelName = [src| diff --git a/src/Data/Aeson/AutoType/Nested.hs b/src/Data/Aeson/AutoType/Nested.hs new file mode 100644 --- /dev/null +++ b/src/Data/Aeson/AutoType/Nested.hs @@ -0,0 +1,98 @@ +{-# language DeriveGeneric #-} +{-# language OverloadedStrings #-} +-- | Simple interface for using AutoType inference +-- in other code generators. +-- +-- Simply takes a list of Aeson values, +-- and returns a type description. +-- +-- For this type description, +-- we can use function to generate an entire new module. +-- +-- Note that while we can put more code in the module, +-- it is recommended to avoid multiple automatically +-- generated types in order to avoid name conflicts. +module Data.Aeson.AutoType.Nested( + defaultImportedModules + , generateModuleImports + , inferType + , CodeFragment + , TypeName + , DeclaredType(..) + ) where + +import Data.Aeson +import Data.Aeson.AutoType.CodeGen.Haskell(generateModuleImports, requiredPackages, importedModules) +import Data.Aeson.AutoType.CodeGen.HaskellFormat(displaySplitTypes) +import Data.Aeson.AutoType.Extract(extractType, unifyTypes) +import Data.Aeson.AutoType.Split(splitTypeByLabel) +import Data.Default +import Data.Typeable +import Data.Text(Text) +import GHC.Generics + +-- FIXME: general type to compose generated types +-- move to JSON Autotype as library interface? +-- * API Response Structures +type CodeFragment = Text +type TypeName = Text +type ImportedModule = Text +type PackageName = Text + +-- | Type declaration and its requirements +-- Content to embed in an autogenerated module: +-- * name of the type to reference +-- * declarations to describe it +-- * module imports necessary for declarations +-- to work +data DeclaredType = DeclaredType + { + -- | Code fragment to be inserted in generated module + typeCodeFragment :: CodeFragment + -- | Toplevel type name to refer to + , typeName :: TypeName + -- | List of clauses to add to imports list + , typeImportedModules :: [ImportedModule] + -- | List of packages to add to generated package dependencies + , typePackages :: [PackageName] + } + deriving + ( Eq + , Show + , Generic + , Typeable + ) + + +instance Default DeclaredType where + -- Minimal placeholder to use in case we cannot infer proper type + def = DeclaredType { + typeCodeFragment = "" + , typeName = "Data.Aeson.Value" + , typeImportedModules = ["qualified Data.Aeson"] + , typePackages = ["aeson"] + } + +-- | List of modules imported for Autotyped declarations +defaultImportedModules = importedModules + +-- | Given intended type name, and a list of +-- text fields with JSON, return +-- either an error, or an `EndpointResponse` +-- that allows to declare and use this type +-- in generated module. +inferType :: Text -> [Value] -> DeclaredType +inferType typeName [] = def +inferType typeName jsonValues = + DeclaredType { + typeImportedModules = defaultImportedModules + , typeCodeFragment = displaySplitTypes splitTypeDescriptors + , typeName = typeName + , typePackages = requiredPackages + } + where + valueTypes = map extractType jsonValues + -- FIXME: should be <> in Typelike? + unifiedType = foldr1 unifyTypes valueTypes + splitTypeDescriptors = splitTypeByLabel typeName unifiedType + diff --git a/src/Data/Aeson/AutoType/Split.hs b/src/Data/Aeson/AutoType/Split.hs --- a/src/Data/Aeson/AutoType/Split.hs +++ b/src/Data/Aeson/AutoType/Split.hs @@ -62,7 +62,8 @@ splitTypeByLabel' _ TDouble = return TDouble splitTypeByLabel' _ TBool = return TBool splitTypeByLabel' _ TNull = return TNull -splitTypeByLabel' _ (TLabel r) = assert False $ return $ TLabel r -- unnecessary? +splitTypeByLabel' _ (TLabel r) = error $ "Splitting into labelled types after label " + <> show r <> " was already given!" splitTypeByLabel' l (TUnion u) = do m <- mapM (splitTypeByLabel' l) $ Set.toList u return $! TUnion $! Set.fromList m splitTypeByLabel' l (TArray a) = do m <- splitTypeByLabel' (l `Text.append` "Elt") a