feat: split client to separate class

libraries/client.ts

@@ -0,0 +1,146 @@
+import z, { ZodType } from "zod";
+
+import type { RelayAdapter, RequestInput } from "./adapter.ts";
+import type { Route, RouteMethod } from "./route.ts";
+
+export class RelayClient<TRoutes extends Route[]> {
+  /**
+   * Route index in the '${method} ${path}' format allowing for quick access to
+   * a specific route.
+   */
+  readonly #index = new Map<string, Route>();
+
+  /**
+   * Instantiate a new Relay instance.
+   *
+   * @param config - Relay configuration to apply to the instance.
+   * @param routes - Routes to register with the instance.
+   */
+  constructor(readonly config: RelayConfig<TRoutes>) {
+    for (const route of config.routes) {
+      this.#index.set(`${route.method} ${route.path}`, route);
+    }
+  }
+
+  /**
+   * Send a "POST" request through the relay `fetch` adapter.
+   *
+   * @param path - Path to send request to.
+   * @param args - List of request arguments.
+   */
+  async post<
+    TPath extends Extract<TRoutes[number], { state: { method: "POST" } }>["state"]["path"],
+    TRoute extends Extract<TRoutes[number], { state: { method: "POST"; path: TPath } }>,
+  >(path: TPath, ...args: TRoute["args"]): Promise<RelayResponse<TRoute>> {
+    return this.#send("POST", path, args) as RelayResponse<TRoute>;
+  }
+
+  /**
+   * Send a "GET" request through the relay `fetch` adapter.
+   *
+   * @param path - Path to send request to.
+   * @param args - List of request arguments.
+   */
+  async get<
+    TPath extends Extract<TRoutes[number], { state: { method: "GET" } }>["state"]["path"],
+    TRoute extends Extract<TRoutes[number], { state: { method: "GET"; path: TPath } }>,
+  >(path: TPath, ...args: TRoute["args"]): Promise<RelayResponse<TRoute>> {
+    return this.#send("GET", path, args) as RelayResponse<TRoute>;
+  }
+
+  /**
+   * Send a "PUT" request through the relay `fetch` adapter.
+   *
+   * @param path - Path to send request to.
+   * @param args - List of request arguments.
+   */
+  async put<
+    TPath extends Extract<TRoutes[number], { state: { method: "PUT" } }>["state"]["path"],
+    TRoute extends Extract<TRoutes[number], { state: { method: "PUT"; path: TPath } }>,
+  >(path: TPath, ...args: TRoute["args"]): Promise<RelayResponse<TRoute>> {
+    return this.#send("PUT", path, args) as RelayResponse<TRoute>;
+  }
+
+  /**
+   * Send a "PATCH" request through the relay `fetch` adapter.
+   *
+   * @param path - Path to send request to.
+   * @param args - List of request arguments.
+   */
+  async patch<
+    TPath extends Extract<TRoutes[number], { state: { method: "PATCH" } }>["state"]["path"],
+    TRoute extends Extract<TRoutes[number], { state: { method: "PATCH"; path: TPath } }>,
+  >(path: TPath, ...args: TRoute["args"]): Promise<RelayResponse<TRoute>> {
+    return this.#send("PATCH", path, args) as RelayResponse<TRoute>;
+  }
+
+  /**
+   * Send a "DELETE" request through the relay `fetch` adapter.
+   *
+   * @param path - Path to send request to.
+   * @param args - List of request arguments.
+   */
+  async delete<
+    TPath extends Extract<TRoutes[number], { state: { method: "DELETE" } }>["state"]["path"],
+    TRoute extends Extract<TRoutes[number], { state: { method: "DELETE"; path: TPath } }>,
+  >(path: TPath, ...args: TRoute["args"]): Promise<RelayResponse<TRoute>> {
+    return this.#send("DELETE", path, args) as RelayResponse<TRoute>;
+  }
+
+  async #send(method: RouteMethod, url: string, args: any[]) {
+    const route = this.#index.get(`${method} ${url}`);
+    if (route === undefined) {
+      throw new Error(`RelayClient > Failed to send request for '${method} ${url}' route, not found.`);
+    }
+
+    // ### Input
+
+    const input: RequestInput = { method, url: `${this.config.url}${url}`, search: "" };
+
+    let index = 0; // argument incrementor
+
+    if (route.state.params !== undefined) {
+      const params = args[index++] as { [key: string]: string };
+      for (const key in params) {
+        input.url = input.url.replace(`:${key}`, params[key]);
+      }
+    }
+
+    if (route.state.search !== undefined) {
+      const search = args[index++] as { [key: string]: string };
+      const pieces: string[] = [];
+      for (const key in search) {
+        pieces.push(`${key}=${search[key]}`);
+      }
+      if (pieces.length > 0) {
+        input.search = `?${pieces.join("&")}`;
+      }
+    }
+
+    if (route.state.body !== undefined) {
+      input.body = JSON.stringify(args[index++]);
+    }
+
+    // ### Fetch
+
+    const data = await this.config.adapter.fetch(input);
+    if (route.state.output !== undefined) {
+      return route.state.output.parse(data);
+    }
+    return data;
+  }
+}
+
+/*
+ |--------------------------------------------------------------------------------
+ | Types
+ |--------------------------------------------------------------------------------
+ */
+
+type RelayResponse<TRoute extends Route> = TRoute["state"]["output"] extends ZodType ? z.infer<TRoute["state"]["output"]> : void;
+
+type RelayConfig<TRoutes extends Route[]> = {
+  url: string;
+  adapter: RelayAdapter;
+  routes: TRoutes;
+};