Add extensions field to error response

kgraphql-example/src/main/kotlin/com/apurebase/kgraphql/Application.kt

@@ -23,6 +23,10 @@ fun Application.module() {
     install(GraphQL) {
         useDefaultPrettyPrinter = true
         playground = true
+        /**
+         * Change 2: Added debug option to GraphQL Configuration (flag to output exception information to extensions)
+         */
+        debug = false
         endpoint = "/"
 
         wrap {

kgraphql-ktor/src/main/kotlin/com/apurebase/kgraphql/KtorFeature.kt

@@ -10,7 +10,6 @@ import io.ktor.response.*
 import io.ktor.routing.*
 import io.ktor.util.*
 import kotlinx.coroutines.coroutineScope
-import kotlinx.serialization.json.*
 import kotlinx.serialization.json.Json.Default.decodeFromString
 
 class GraphQL(val schema: Schema) {
@@ -27,6 +26,11 @@ class GraphQL(val schema: Schema) {
 
         var endpoint: String = "/graphql"
 
+        /**
+         * Change 2: Added debug option to GraphQL Configuration (flag to output exception information to extensions)
+         */
+        var debug: Boolean = false
+
         fun context(block: ContextBuilder.(ApplicationCall) -> Unit) {
             contextSetup = block
         }
@@ -83,31 +87,12 @@ class GraphQL(val schema: Schema) {
                     }
                 } catch (e: Throwable) {
                     if (e is GraphQLError) {
-                        context.respond(HttpStatusCode.OK, e.serialize())
+                        context.respond(HttpStatusCode.OK, e.serialize(config.debug))
                     } else throw e
                 }
             }
             return GraphQL(schema)
         }
-
-        private fun GraphQLError.serialize(): String = buildJsonObject {
-            put("errors", buildJsonArray {
-                addJsonObject {
-                    put("message", message)
-                    put("locations", buildJsonArray {
-                        locations?.forEach {
-                            addJsonObject {
-                                put("line", it.line)
-                                put("column", it.column)
-                            }
-                        }
-                    })
-                    put("path", buildJsonArray {
-                        // TODO: Build this path. https://spec.graphql.org/June2018/#example-90475
-                    })
-                }
-            })
-        }.toString()
     }
 
 }

kgraphql/src/main/kotlin/com/apurebase/kgraphql/GraphQLError.kt

@@ -1,8 +1,10 @@
 package com.apurebase.kgraphql
 
+import com.apurebase.kgraphql.helpers.toJsonElement
 import com.apurebase.kgraphql.schema.model.ast.ASTNode
 import com.apurebase.kgraphql.schema.model.ast.Location.Companion.getLocation
 import com.apurebase.kgraphql.schema.model.ast.Source
+import kotlinx.serialization.json.*
 
 open class GraphQLError(
 
@@ -33,10 +35,19 @@ open class GraphQLError(
     /**
      * The original error thrown from a field resolver during execution.
      */
-    val originalError: Throwable? = null
+    val originalError: Throwable? = null,
+
+    /**
+     * Change 1: Added extensions to the error response.
+     */
+    val extensionsErrorType: String? = "INTERNAL_SERVER_ERROR",
+    val extensionsErrorDetail: Map<String, Any?>? = null
 ) : Exception(message) {
 
     constructor(message: String, node: ASTNode?) : this(message, nodes = node?.let(::listOf))
+    constructor(message: String, extensionsErrorType: String?,extensionsErrorDetail:Map<String, Any?>?) : this(message,null,null,null,null,extensionsErrorType,extensionsErrorDetail )
+    constructor(message: String, extensionsErrorType: String?) : this(message,null,null,null,null,extensionsErrorType )
+
 
     /**
      * An array of { line, column } locations within the source GraphQL document
@@ -71,4 +82,69 @@ open class GraphQLError(
 
         return output
     }
+
+    /**
+     * Change 1: Added extensions to the error response.
+     * Change 2: Added debug option to GraphQL Configuration (flag to output exception information to extensions)
+     * Change 3: Moved serialize (), which was defined as an extension of GraphQLError, into GraphQLError. option
+     */
+    open val extensions: Map<String,Any?>?by lazy {
+        val extensions = mutableMapOf<String,Any?>()
+        extensionsErrorType?.let{  extensions.put("type",extensionsErrorType) }
+        extensionsErrorDetail?.let { extensions.put("detail",extensionsErrorDetail) }
+        extensions
+    }
+
+    open fun extensionsDebug(): Map<String,Any?> {
+        val extensions = mutableMapOf<String,Any?>()
+        extensionsErrorType?.let{  extensions.put("type",extensionsErrorType) }
+        extensionsErrorDetail?.let { extensions.put("detail",extensionsErrorDetail) }
+        extensions.put("debug",this.debugInfo())
+        return extensions
+    }
+
+    open fun debugInfo(): Map<String,Any?> {
+        val exception = mutableMapOf<String,Any?>()
+        val stackList = this.stackTrace
+        if (!stackList[0].fileName.isNullOrEmpty()) {
+            exception.put("fileName",stackList[0].fileName)
+            exception.put("line",stackList[0].lineNumber.toString())
+        }
+        if (!stackList[0].methodName.isNullOrEmpty()) {
+            exception.put("method",stackList[0].methodName)
+        }
+        if (!stackList[0].className.isNullOrEmpty()) {
+            exception.put("classPath", stackList[0].className)
+        }
+        exception.put("stackTrace", stackList)
+        return  exception
+    }
+
+    open fun serialize(debug:Boolean=false): String = buildJsonObject {
+        put("errors", buildJsonArray {
+            addJsonObject {
+                put("message", message)
+                put("locations", buildJsonArray {
+                    locations?.forEach {
+                        addJsonObject {
+                            put("liane", it.line)
+                            put("column", it.column)
+                        }
+                    }
+                })
+                put("path", buildJsonArray {
+                    // TODO: Build this path. https://spec.graphql.org/June2018/#example-90475
+                })
+                if (!debug) {
+                    extensions?.let {
+                        put("extensions", it.toJsonElement())
+                    }
+                } else {
+                    extensionsDebug().let {
+                        put("extensions", it.toJsonElement())
+                    }
+                }
+            }
+        })
+    }.toString()
 }

kgraphql/src/main/kotlin/com/apurebase/kgraphql/helpers/KGraphQLExtensions.kt

@@ -1,6 +1,10 @@
 package com.apurebase.kgraphql.helpers
 
 import com.apurebase.kgraphql.schema.execution.Execution
+import kotlinx.serialization.json.JsonArray
+import kotlinx.serialization.json.JsonElement
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
 
 /**
  * This returns a list of all scalar fields requested on this type.
@@ -16,3 +20,44 @@ fun Execution.getFields(): List<String> = when (this) {
     }
     else -> listOf()
 }.distinct()
+
+/**
+ * Collection : Convert to JsonElement
+ */
+fun Collection<*>.toJsonElement(): JsonElement {
+    val list: MutableList<JsonElement> = mutableListOf()
+    this.forEach {
+        val value = it as? Any ?: return@forEach
+        when(value) {
+            is Number -> list.add(JsonPrimitive(value))
+            is Boolean -> list.add(JsonPrimitive(value))
+            is String -> list.add(JsonPrimitive(value))
+            is Map<*, *> -> list.add((value).toJsonElement())
+            is Collection<*> -> list.add(value.toJsonElement())
+            is Array<*> -> list.add(value.toList().toJsonElement())
+            else -> list.add(JsonPrimitive(value.toString())) // other type
+        }
+    }
+    return JsonArray(list)
+}
+
+/**
+ * Map : Convert to JsonElement
+ */
+fun Map<*, *>.toJsonElement(): JsonElement {
+    val map: MutableMap<String, JsonElement> = mutableMapOf()
+    this.forEach {
+        val key = it.key as? String ?: return@forEach
+        val value = it.value ?: return@forEach
+        when(value) {
+            is Number? -> map[key] = JsonPrimitive(value)
+            is Boolean? -> map[key] = JsonPrimitive(value)
+            is String? -> map[key] = JsonPrimitive(value)
+            is Map<*, *> -> map[key] = (value).toJsonElement()
+            is Collection<*> -> map[key] = value.toJsonElement()
+            is Array<*> -> map[key] = value.toList().toJsonElement()
+            else -> map[key] = JsonPrimitive(value.toString())  // other type
+        }
+    }
+    return JsonObject(map)
+}