More lenient types for search parameters

Author: sebastianquek

CHANGELOG.md

@@ -10,9 +10,13 @@ and this project adheres to
 
 ### Added
 
+- Expose `EngineName` and `EngineParameters` types.
+
 ### Changed
 
 - Remove `settings.json`, update CONTRIBUTING.md.
+- Make types more lenient so newly supported engines/parameters whose types have
+  not yet been updated do not throw warnings.
 
 ### Fixed
 

mod.ts

@@ -8,6 +8,8 @@ export type {
   AccountInformation,
   BaseParameters,
   BaseResponse,
+  EngineName,
+  EngineParameters,
   GetBySearchIdParameters,
   Location,
   Locations,

src/serpapi.ts

@@ -2,11 +2,12 @@ import {
   AccountApiParameters,
   AccountInformation,
   BaseResponse,
+  EngineName,
+  EngineParameters,
   GetBySearchIdParameters,
   Locations,
   LocationsApiParameters,
 } from "./types.ts";
-import { EngineMap } from "./engines/engine_map.ts";
 import {
   _internals,
   execute,
@@ -69,11 +70,12 @@ const SEARCH_ARCHIVE_PATH = `/searches`;
  * });
  */
 export async function getJson<
-  E extends keyof EngineMap,
+  E extends EngineName = EngineName,
+  P extends EngineParameters<E> = EngineParameters<E>,
 >(
   engine: E,
-  parameters: EngineMap[E]["parameters"],
-  callback?: (json: BaseResponse<EngineMap[E]["parameters"]>) => void,
+  parameters: P,
+  callback?: (json: BaseResponse<P>) => void,
 ) {
   const key = validateApiKey(parameters.api_key, true);
   const timeout = validateTimeout(parameters.timeout);
@@ -87,9 +89,7 @@ export async function getJson<
     },
     timeout,
   );
-  const json = await response.json() as BaseResponse<
-    EngineMap[E]["parameters"]
-  >;
+  const json = await response.json() as BaseResponse<P>;
   const nextParametersFromResponse = extractNextParameters<E>(json);
   if (
     // https://github.com/serpapi/public-roadmap/issues/562
@@ -126,9 +126,12 @@ export async function getJson<
  * // callback
  * getHtml("google", { api_key: API_KEY, q: "coffee" }, console.log);
  */
-export async function getHtml<E extends keyof EngineMap>(
+export async function getHtml<
+  E extends EngineName = EngineName,
+  P extends EngineParameters<E> = EngineParameters<E>,
+>(
   engine: E,
-  parameters: EngineMap[E]["parameters"],
+  parameters: P,
   callback?: (html: string) => void,
 ) {
   const key = validateApiKey(parameters.api_key, true);

src/types.ts

@@ -1,3 +1,5 @@
+import { EngineMap } from "./engines/engine_map.ts";
+
 export type BaseParameters = {
   /**
    * Parameter defines the device to use to get the results. It can be set to
@@ -39,7 +41,19 @@ export type BaseParameters = {
    */
   timeout?: number;
 };
-export type BaseResponse<P = Record<string | number | symbol, never>> = {
+
+// https://github.com/microsoft/TypeScript/issues/29729
+// deno-lint-ignore ban-types
+type AnyEngineName = string & {};
+export type EngineName = (keyof EngineMap) | AnyEngineName;
+export type EngineParameters<
+  E extends EngineName = EngineName,
+> = {
+  [K in E]: K extends keyof EngineMap ? EngineMap[K]["parameters"]
+    : BaseParameters & Record<string, unknown>;
+}[E];
+
+export type BaseResponse<P = Record<string, unknown>> = {
   search_metadata: {
     id: string;
     status: "Queued" | "Processing" | "Success";

src/utils.ts

@@ -1,4 +1,4 @@
-import type { EngineMap } from "./engines/engine_map.ts";
+import type { EngineName, EngineParameters } from "./types.ts";
 import { version } from "../version.ts";
 
 type UrlParameters = Record<
@@ -35,16 +35,15 @@ function getBaseUrl() {
   return "https://serpapi.com";
 }
 
-type NextParametersKeys<E extends keyof EngineMap> = Omit<
-  EngineMap[E]["parameters"],
-  "api_key" | "no_cache" | "async" | "timeout"
->;
-type NextParameters<E extends keyof EngineMap> = {
-  [K in keyof NextParametersKeys<E>]: string;
+type NextParameters<E extends EngineName = EngineName> = {
+  [
+    K in keyof Omit<
+      EngineParameters<E>,
+      "api_key" | "no_cache" | "async" | "timeout"
+    >
+  ]: string;
 };
-export function extractNextParameters<
-  E extends keyof EngineMap,
->(json: {
+export function extractNextParameters<E extends EngineName = EngineName>(json: {
   serpapi_pagination?: { next: string };
   pagination?: { next: string };
 }) {