From be9128be4f68fd3a02298eb090eda94779a29445 Mon Sep 17 00:00:00 2001
From: TomokiMiyauci <development.operation.6.6.6@gmail.com>
Date: Thu, 4 Aug 2022 12:28:08 +0900
Subject: [PATCH] feat(parses.ts): add `parseGraphQLParameters` that parse
 value as GraphQL parameters

---
 deps.ts   | 17 +++++++++---
 mod.ts    |  2 ++
 parses.ts | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 93 insertions(+), 4 deletions(-)
 create mode 100644 parses.ts

diff --git a/deps.ts b/deps.ts
index 794734d..417b553 100644
--- a/deps.ts
+++ b/deps.ts
@@ -19,15 +19,16 @@ export {
 export {
   contentType,
   parseMediaType,
-} from "https://deno.land/std@0.148.0/media_types/mod.ts";
-export { accepts } from "https://deno.land/std@0.148.0/http/negotiation.ts";
+} from "https://deno.land/std@0.150.0/media_types/mod.ts";
+export { accepts } from "https://deno.land/std@0.150.0/http/negotiation.ts";
 export {
   isNil,
   isNull,
   isObject,
+  isPlainObject,
   isString,
   isUndefined,
-} from "https://deno.land/x/isx@v1.0.0-beta.17/mod.ts";
+} from "https://deno.land/x/isx@1.0.0-beta.19/mod.ts";
 export {
   JSON,
   type json,
@@ -42,7 +43,7 @@ export {
   createHttpError,
   HttpError,
   Status,
-} from "https://deno.land/std@0.148.0/http/mod.ts";
+} from "https://deno.land/std@0.150.0/http/mod.ts";
 
 export type PartialBy<T, K = keyof T> =
   Omit<T, K & keyof T> & Partial<Pick<T, K & keyof T>> extends infer U
@@ -84,3 +85,11 @@ export async function tryCatch<T>(
     return [, er];
   }
 }
+
+// deno-lint-ignore no-explicit-any
+export function has<T extends Record<any, any>, K extends string>(
+  value: T,
+  key: K,
+): value is T & Record<K, unknown> {
+  return key in value;
+}
diff --git a/mod.ts b/mod.ts
index 6c73503..ef97631 100644
--- a/mod.ts
+++ b/mod.ts
@@ -4,3 +4,5 @@ export { createRequest, resolveRequest } from "./requests.ts";
 export { createResponse, resolveResponse } from "./responses.ts";
 export { gql } from "./utils.ts";
 export { default as usePlayground } from "./use/playground.ts";
+export { parseGraphQLParameters } from "./parses.ts";
+export { type GraphQLParameters } from "./types.ts";
diff --git a/parses.ts b/parses.ts
new file mode 100644
index 0000000..1a38d27
--- /dev/null
+++ b/parses.ts
@@ -0,0 +1,78 @@
+import { has, isNull, isPlainObject, isString } from "./deps.ts";
+import { GraphQLParameters } from "./types.ts";
+
+/** Parse value as {@link GraphQLParameters}. */
+export function parseGraphQLParameters(
+  value: unknown,
+): [data: GraphQLParameters] | [data: undefined, error: TypeError] {
+  if (!isPlainObject(value)) {
+    return [
+      ,
+      TypeError(
+        `Invalid field. "payload" must be plain object.`,
+      ),
+    ];
+  }
+
+  if (!has(value, "query")) {
+    return [
+      ,
+      TypeError(
+        `Missing field. "query"`,
+      ),
+    ];
+  }
+
+  if (!isString(value.query)) {
+    return [
+      ,
+      TypeError(
+        `Invalid field. "query" must be string.`,
+      ),
+    ];
+  }
+
+  if (
+    has(value, "variables") &&
+    (!isNull(value.variables) && !isPlainObject(value.variables))
+  ) {
+    return [
+      ,
+      TypeError(
+        `Invalid field. "variables" must be plain object or null`,
+      ),
+    ];
+  }
+  if (
+    has(value, "operationName") &&
+    (!isNull(value.operationName) && !isString(value.operationName))
+  ) {
+    return [
+      ,
+      TypeError(
+        `Invalid field. "operationName" must be string or null.`,
+      ),
+    ];
+  }
+  if (
+    has(value, "extensions") &&
+    (!isNull(value.extensions) && !isPlainObject(value.extensions))
+  ) {
+    return [
+      ,
+      TypeError(
+        `Invalid field. "extensions" must be plain object or null`,
+      ),
+    ];
+  }
+
+  const { query, ...rest } = value;
+
+  return [{
+    operationName: null,
+    variableValues: null,
+    extensions: null,
+    query,
+    ...rest,
+  }];
+}