[feat][elixir] use elixir 1.18 built-in json module (#21039)

* feat: replace jason by built-in json encoder/decoder

* chore: update samples

Author: efcasado

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElixirClientCodegen.java

@@ -57,11 +57,10 @@ public class ElixirClientCodegen extends DefaultCodegen {
     // This is the name of elixir project name;
     protected static final String defaultPackageName = "openapi_client";
 
-    String supportedElixirVersion = "1.10";
+    String supportedElixirVersion = "1.18";
     List<String> extraApplications = Arrays.asList(":logger");
     List<String> deps = Arrays.asList(
             "{:tesla, \"~> 1.7\"}",
-            "{:jason, \"~> 1.4\"}",
             "{:ex_doc, \"~> 0.30\", only: :dev, runtime: false}",
             "{:dialyxir, \"~> 1.3\", only: [:dev, :test], runtime: false}");
 
@@ -694,7 +693,7 @@ public String codeMappingKey() {
         }
 
         public String decodedStruct() {
-            // Let Jason decode the entire response into a generic blob
+            // Decode the entire response into a generic blob
             if (isMap) {
                 return "%{}";
             }

modules/openapi-generator/src/main/resources/elixir/connection.ex.mustache

@@ -216,7 +216,7 @@ defmodule {{moduleName}}.Connection do
 
     tesla_options = Application.get_env(:tesla, __MODULE__, [])
     middleware = Keyword.get(tesla_options, :middleware, [])
-    json_engine = Keyword.get(tesla_options, :json, Jason)
+    json_engine = Keyword.get(tesla_options, :json, JSON)
 
     user_agent =
       Keyword.get(

modules/openapi-generator/src/main/resources/elixir/deserializer.ex.mustache

@@ -4,15 +4,13 @@ defmodule {{moduleName}}.Deserializer do
   Helper functions for deserializing responses into models
   """
 
-  @jason_decode_opts [keys: :strings]
-
-  def jason_decode(json) do
-    Jason.decode(json, @jason_decode_opts)
+  def json_decode(json) do
+    JSON.decode(json)
   end
 
-  def jason_decode(json, module) do
+  def json_decode(json, module) do
     json
-    |> jason_decode()
+    |> json_decode()
     |> case do
       {:ok, decoded} -> {:ok, to_struct(decoded, module)}
       {:error, _} = error -> error

modules/openapi-generator/src/main/resources/elixir/model.mustache

@@ -4,7 +4,7 @@
   {{&description}}
   """
 
-  @derive Jason.Encoder
+  @derive JSON.Encoder
   defstruct [
     {{#vars}}{{#atom}}{{&baseName}}{{/atom}}{{^-last}},
     {{/-last}}{{/vars}}

modules/openapi-generator/src/main/resources/elixir/request_builder.ex.mustache

@@ -94,7 +94,7 @@ defmodule {{moduleName}}.RequestBuilder do
       Tesla.Multipart.add_field(
         multipart,
         key,
-        Jason.encode!(value),
+        JSON.encode!(value),
         headers: [{:"Content-Type", "application/json"}]
       )
     end)
@@ -187,10 +187,10 @@ defmodule {{moduleName}}.RequestBuilder do
   defp decode(%Tesla.Env{} = env, false), do: {:ok, env}
 
   defp decode(%Tesla.Env{body: body}, %{}) do
-    {{moduleName}}.Deserializer.jason_decode(body)
+    {{moduleName}}.Deserializer.json_decode(body)
   end
 
   defp decode(%Tesla.Env{body: body}, module) do
-    {{moduleName}}.Deserializer.jason_decode(body, module)
+    {{moduleName}}.Deserializer.json_decode(body, module)
   end
 end

samples/client/petstore/elixir/lib/openapi_petstore/connection.ex

@@ -153,7 +153,7 @@ defmodule OpenapiPetstore.Connection do
 
     tesla_options = Application.get_env(:tesla, __MODULE__, [])
     middleware = Keyword.get(tesla_options, :middleware, [])
-    json_engine = Keyword.get(tesla_options, :json, Jason)
+    json_engine = Keyword.get(tesla_options, :json, JSON)
 
     user_agent =
       Keyword.get(

samples/client/petstore/elixir/lib/openapi_petstore/deserializer.ex

@@ -6,15 +6,13 @@ defmodule OpenapiPetstore.Deserializer do
   Helper functions for deserializing responses into models
   """
 
-  @jason_decode_opts [keys: :strings]
-
-  def jason_decode(json) do
-    Jason.decode(json, @jason_decode_opts)
+  def json_decode(json) do
+    JSON.decode(json)
   end
 
-  def jason_decode(json, module) do
+  def json_decode(json, module) do
     json
-    |> jason_decode()
+    |> json_decode()
     |> case do
       {:ok, decoded} -> {:ok, to_struct(decoded, module)}
       {:error, _} = error -> error

samples/client/petstore/elixir/lib/openapi_petstore/model/_foo_get_default_response.ex

@@ -6,7 +6,7 @@ defmodule OpenapiPetstore.Model.FooGetDefaultResponse do
   
   """
 
-  @derive Jason.Encoder
+  @derive JSON.Encoder
   defstruct [
     :string
   ]

samples/client/petstore/elixir/lib/openapi_petstore/model/_special_model_name_.ex

@@ -6,7 +6,7 @@ defmodule OpenapiPetstore.Model.SpecialModelName do
   
   """
 
-  @derive Jason.Encoder
+  @derive JSON.Encoder
   defstruct [
     :"$special[property.name]"
   ]

samples/client/petstore/elixir/lib/openapi_petstore/model/additional_properties_class.ex

@@ -6,7 +6,7 @@ defmodule OpenapiPetstore.Model.AdditionalPropertiesClass do
   
   """
 
-  @derive Jason.Encoder
+  @derive JSON.Encoder
   defstruct [
     :map_property,
     :map_of_map_property