#45, parse "null" init value

Author: hauner

src/main/kotlin/io/openapiprocessor/core/converter/mapping/NullTypeMapping.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2020 https://github.com/openapi-processor/openapi-processor-core
+ * PDX-License-Identifier: Apache-2.0
+ */
+
+package io.openapiprocessor.core.converter.mapping
+
+/**
+ * Used with [io.openapiprocessor.core.converter.ApiOptions.typeMappings] to map an OpenAPI nullable
+ * property to a wrapper type of the plain type. E.g. org.openapitools.jackson.nullable.JsonNullable
+ */
+class NullTypeMapping(
+
+    /**
+     * The OpenAPI schema type that should be mapped to the {@link #targetTypeName} java type.
+     */
+    val sourceTypeName: String = "null",
+
+    /**
+     * The fully qualified java type name that will be used as the result type.
+     */
+    val targetTypeName: String,
+
+    /**
+     * An "undefined" value that should be used as the initial value of the property. e.g.
+     * JonNullable.undefined()
+     */
+    val undefined: String? = null
+
+): Mapping, TargetTypeMapping  {
+
+    /**
+     * Returns the target type of this type mapping.
+     *
+     * @return the target type
+     */
+    override fun getTargetType (): TargetType {
+        return TargetType(targetTypeName, emptyList())
+    }
+
+    override fun getChildMappings(): List<Mapping> {
+        return listOf(this)
+    }
+
+}

src/main/kotlin/io/openapiprocessor/core/processor/mapping/v2/MappingConverter.kt

@@ -55,7 +55,7 @@ class MappingConverter(val mapping: MappingV2) {
         }
 
         if(mapping.map.`null` != null) {
-            result.add(convertType("null", mapping.map.`null`))
+            result.add(convertNull(mapping.map.`null`))
         }
 
         mapping.map.types.forEach {
@@ -81,6 +81,19 @@ class MappingConverter(val mapping: MappingV2) {
         return ResultTypeMapping(result)
     }
 
+    private fun convertNull(value: String): Mapping {
+        val split = value
+                .split(" = ")
+                .map { it.trim() }
+
+        val type = split.component1()
+        var init: String? = null
+        if (split.size == 2)
+            init = split.component2()
+
+        return NullTypeMapping("null", type, init)
+    }
+
     private fun convertType (from: String, to: String): Mapping {
         return TypeMapping(from, to)
     }
@@ -144,7 +157,7 @@ class MappingConverter(val mapping: MappingV2) {
         }
 
         if(source.`null` != null) {
-            result.add(convertType("null", source.`null`))
+            result.add(convertNull(source.`null`))
         }
 
         source.types.forEach {

src/test/kotlin/io/openapiprocessor/core/processor/mapping/v2/MappingConverterSpec.kt

@@ -8,6 +8,7 @@ package io.openapiprocessor.core.processor.mapping.v2
 import io.kotest.core.spec.IsolationMode
 import io.kotest.core.spec.style.StringSpec
 import io.kotest.matchers.shouldBe
+import io.openapiprocessor.core.converter.mapping.NullTypeMapping
 import io.openapiprocessor.core.converter.mapping.TypeMapping
 import io.openapiprocessor.core.processor.MappingConverter
 import io.openapiprocessor.core.processor.MappingReader
@@ -56,7 +57,7 @@ class MappingConverterSpec: StringSpec({
         val mappings = converter.convert (mapping)
 
         // then:
-        val `null` = mappings.first() as TypeMapping
+        val `null` = mappings.first() as NullTypeMapping
         `null`.targetTypeName shouldBe "org.openapitools.jackson.nullable.JsonNullable"
     }
 
@@ -78,7 +79,29 @@ class MappingConverterSpec: StringSpec({
         val mappings = converter.convert (mapping)
 
         // then:
-        val `null` = mappings.first().getChildMappings().first() as TypeMapping
+        val `null` = mappings.first().getChildMappings().first() as NullTypeMapping
+        `null`.targetTypeName shouldBe "org.openapitools.jackson.nullable.JsonNullable"
+    }
+
+    "read endpoint 'null' mapping with init value" {
+        val yaml = """
+                   |openapi-processor-mapping: v2
+                   |
+                   |options:
+                   |  package-name: io.openapiprocessor.somewhere
+                   | 
+                   |map:
+                   |  paths:
+                   |    /foo:
+                   |      null: org.openapitools.jackson.nullable.JsonNullable = JsonNullable.undefined()
+                   """.trimMargin()
+
+        // when:
+        val mapping = reader.read (yaml)
+        val mappings = converter.convert (mapping)
+
+        // then:
+        val `null` = mappings.first().getChildMappings().first() as NullTypeMapping
         `null`.targetTypeName shouldBe "org.openapitools.jackson.nullable.JsonNullable"
     }