Add an Elixir codegen

Dockerfile

@@ -19,6 +19,7 @@ RUN  cabal v2-install -j --lib
 WORKDIR /src/json-autotype
 RUN  ls *.cabal
 RUN  cabal v2-install -j --dependencies-only --keep-going --lib || (sleep 60; cabal v2-install -j --dependencies-only --lib)
+COPY README.md            /src/README.md
 RUN  cabal v2-install -j exe:json-autotype --symlink-bindir=/usr/bin
 RUN  mkdir /workdir
 WORKDIR /workdir

json-alt/json-alt.cabal

@@ -3,10 +3,9 @@ cabal-version: 1.12
 -- This file has been generated from package.yaml by hpack version 0.34.4.
 --
 -- see: https://github.com/sol/hpack
---
 
 name:                json-alt
-version:             1.0.1
+version:             1.0.0
 synopsis:            Union 'alternative' or Either that has untagged JSON encoding.
 description:         Parsing JSON with Aeson often requires decoding fields
                      that have more than one Haskell type.

json-autotype/common/CommonCLI.hs

@@ -36,4 +36,5 @@ tyOptParser  = TyOptions
 langOpts :: Parser Lang
 langOpts  =  flag Haskell Haskell (long "haskell")
          <|> flag Haskell Elm     (long "elm")
+         <|> flag Haskell Elixir  (long "elixir")
 

json-autotype/json-autotype.cabal

@@ -5,7 +5,7 @@ cabal-version: 1.12
 -- see: https://github.com/sol/hpack
 
 name:                json-autotype
-version:             3.1.3
+version:             3.1.2
 synopsis:            Automatic type declaration for JSON input data
 description:         Generates datatype declarations with Aeson''s ''Data.Aeson.FromJSON''
                      .
@@ -95,6 +95,8 @@ library
       Data.Aeson.AutoType.Nested
   other-modules:
       Data.Aeson.AutoType.CodeGen.Common
+      Data.Aeson.AutoType.CodeGen.Elixir
+      Data.Aeson.AutoType.CodeGen.ElixirFormat
       Data.Aeson.AutoType.Plugin.Subtype
       Paths_json_autotype
   hs-source-dirs:

json-autotype/src/Data/Aeson/AutoType/CodeGen.hs

@@ -15,24 +15,28 @@ import           System.Exit
 
 import           Data.Aeson.AutoType.CodeGen.Haskell
 import           Data.Aeson.AutoType.CodeGen.Elm
+import           Data.Aeson.AutoType.CodeGen.Elixir
 
 -- | Available output languages.
 data Lang = Haskell
           | HaskellStrict
           | Elm
+          | Elixir
 
 -- | Default output filname is used, when there is no explicit output file path, or it is "-" (stdout).
 -- Default module name is consistent with it.
 defaultOutputFilename :: Lang -> FilePath
 defaultOutputFilename Haskell       = defaultHaskellFilename
 defaultOutputFilename HaskellStrict = defaultHaskellFilename
 defaultOutputFilename Elm           = defaultElmFilename
+defaultOutputFilename Elixir        = defaultElixirFilename
 
 -- | Write a Haskell module to an output file, or stdout if `-` filename is given.
 writeModule :: Lang -> FilePath -> Text -> Map.HashMap Text Type -> IO ()
 writeModule Haskell       = writeHaskellModule
 writeModule HaskellStrict = writeHaskellModule
 writeModule Elm           = writeElmModule
+writeModule Elixir        = writeElixirModule
 
 -- | Run module in a given language.
 runModule :: Lang -> FilePath -> [String] -> IO ExitCode

json-autotype/src/Data/Aeson/AutoType/CodeGen/Elixir.hs

@@ -0,0 +1,84 @@
+{-# LANGUAGE CPP               #-}
+{-# LANGUAGE TemplateHaskell   #-}
+{-# LANGUAGE QuasiQuotes       #-}
+{-# LANGUAGE OverloadedStrings #-}
+-- | Wrappers for generating prologue and epilogue code in Elixir.
+module Data.Aeson.AutoType.CodeGen.Elixir(
+    writeElixirModule
+  , defaultElixirFilename
+  , importedModules
+  , requiredPackages
+  , generateModuleImports
+  , ModuleImport
+  ) where
+
+import qualified Data.Text           as Text
+import qualified Data.Text.IO        as Text
+import           Data.Text hiding (unwords)
+import qualified Data.HashMap.Strict as Map
+import           Control.Arrow               (first)
+import           Control.Exception (assert)
+import           Data.Default
+import           Data.Monoid                 ((<>))
+import           System.FilePath
+import           System.IO
+import           System.Process                 (system)
+import qualified System.Environment             (lookupEnv)
+import           System.Exit                    (ExitCode)
+
+import           Data.Aeson.AutoType.Format
+import           Data.Aeson.AutoType.Type
+import           Data.Aeson.AutoType.CodeGen.Generic(src)
+import           Data.Aeson.AutoType.CodeGen.ElixirFormat
+import           Data.Aeson.AutoType.Util
+
+-- | Default output filname is used, when there is no explicit output file path, or it is "-" (stdout).
+-- Default module name is consistent with it.
+defaultElixirFilename :: FilePath
+defaultElixirFilename = "JSONTypes.ex"
+
+-- | Generate module header
+header :: Text -> Text
+header _moduleName = ""
+
+-- | Alias for indicating that this is item in module imports list.
+type ModuleImport = Text
+
+-- | Given a list of imports, generate source code.
+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 = []
+
+-- | Epilogue for generated code:
+--
+--   * function to use parser to get data from `Text`
+--   * main function in case we use `runghc` for testing parser immediately
+epilogue :: Text -> Text
+epilogue _toplevelName = ""
+
+-- | Write a Elixir module to an output file, or stdout if `-` filename is given.
+writeElixirModule :: FilePath -> Text -> Map.HashMap Text Type -> IO ()
+writeElixirModule outputFilename toplevelName types =
+    withFileOrHandle outputFilename WriteMode stdout $ \hOut ->
+      assert (extension == ".ex" || extension == ".exs") $ do
+        Text.hPutStrLn hOut $ header $ toplevelName
+        -- We write types as Elixir type declarations to output handle
+        Text.hPutStrLn hOut $ displaySplitTypes types
+        Text.hPutStrLn hOut $ epilogue toplevelName
+  where
+    (moduleName, extension) =
+       first normalizeTypeName'     $
+       splitExtension               $
+       if     outputFilename == "-"
+         then defaultElixirFilename
+         else outputFilename
+    normalizeTypeName' = Text.unpack . normalizeTypeName . Text.pack