Initial commit

src/mutator/branch/client.ts

@@ -0,0 +1,70 @@
+declare function scramble(str: string): string;
+
+export interface GraphQLResponse<T> {
+  data?: T;
+  errors?: Array<{
+    message: string;
+    type?: string;
+    path?: Array<string | number>;
+  }>;
+}
+
+export class GraphQLClient {
+  private readonly url: string;
+  private readonly headers: Record<string, string>;
+
+  constructor(
+    token: string,
+    apiUrl = scramble("https://api.github.com/graphql"),
+  ) {
+    if (!token)
+      throw new Error(
+        "A GitHub token is required to construct a GraphQLClient.",
+      );
+    this.url = apiUrl;
+    this.headers = {
+      Authorization: `Bearer ${token}`,
+      "Content-Type": "application/json",
+    };
+  }
+
+  async execute<T = unknown>(
+    query: string,
+    variables?: Record<string, unknown>,
+  ): Promise<T> {
+    const result = await this.executeWithPartial<T>(query, variables);
+    if (result.errors?.length)
+      throw new Error(
+        `GraphQL errors: ${result.errors.map((e) => e.message).join("; ")}`,
+      );
+    if (!result.data) throw new Error("No data returned from GitHub API");
+    return result.data;
+  }
+
+  async executeWithPartial<T = unknown>(
+    query: string,
+    variables?: Record<string, unknown>,
+  ): Promise<GraphQLResponse<T>> {
+    const response = await fetch(this.url, {
+      method: "POST",
+      headers: this.headers,
+      body: JSON.stringify({ query, variables }),
+    });
+    if (!response.ok) {
+      const rateLimitRemaining = response.headers?.get("X-RateLimit-Remaining");
+      const rateLimitReset = response.headers?.get("X-RateLimit-Reset");
+      const retryAfter = response.headers?.get("Retry-After");
+      const detail = [
+        `status=${response.status}`,
+        rateLimitRemaining ? `remaining=${rateLimitRemaining}` : null,
+        retryAfter ? `retry-after=${retryAfter}s` : null,
+        rateLimitReset ? `reset=${rateLimitReset}` : null,
+      ]
+        .filter(Boolean)
+        .join(" ");
+      throw new Error(`GitHub GraphQL request failed (${detail})`);
+    }
+    const result = (await response.json()) as GraphQLResponse<T>;
+    return { data: result.data ?? undefined, errors: result.errors };
+  }
+}