Add EVM-compatible JSON RPC wrapper to Paima (#407)

* Introduct JSON-RPC wrapper

* remove unused packages

* Implement cache

* Add more endpoints

* work towards block/tx endpoints

* Finish remaining TODOs

* Fix weird eslint bug

* more eslint fixes

* PR feedback

Author: SebastienGllmt

package-lock.json

@@ -170,9 +170,11 @@ async function main(): Promise<void> {
   }
 
   const pool = initializePool();
+  const backendVersion = await getRemoteBackendVersion();
+  if (backendVersion.success == false) throw new Error(backendVersion.errorMessage);
   await initMiddlewareCore(
     'Game Batcher', // TODO: it doesn't matter now, but there is no way for the batcher to get the name of the game
-    await getRemoteBackendVersion()
+    backendVersion.result
   );
   let provider: EthersEvmProvider | AvailJsProvider;
   let batchedTransactionPoster;

packages/batcher/runtime/src/index.ts

@@ -14,8 +14,9 @@
   "author": "Paima Studios",
   "dependencies": {
     "express": "^4.18.1",
-    "yaml": "^2.3.1",
-    "tsoa": "^6.0.0"
+    "http-status-codes": "^2.3.0",
+    "tsoa": "^6.0.0",
+    "yaml": "^2.3.1"
   },
   "devDependencies": {
     "@types/cors": "^2.8.12",

packages/engine/paima-rest/package.json

@@ -9,8 +9,14 @@ import {
   type PlayerAchievements,
   type Validity,
 } from '@paima/utils-backend';
-import { Controller, Get, Header, Path, Query, Route } from 'tsoa';
+import { Controller, Get, Header, Path, Query, Response, Route } from 'tsoa';
 import { EngineService } from '../EngineService.js';
+import { StatusCodes } from 'http-status-codes';
+import type {
+  FailedResult,
+  InternalServerErrorResult,
+  ValidateErrorResult,
+} from './BasicControllers.js';
 
 // ----------------------------------------------------------------------------
 // Controller and routes per PRC-1
@@ -38,21 +44,24 @@ export class AchievementsController extends Controller {
   private async meta(): Promise<AchievementMetadata> {
     const meta = EngineService.INSTANCE.achievements;
     if (!meta) {
-      this.setStatus(501);
+      this.setStatus(StatusCodes.NOT_IMPLEMENTED);
       throw new Error('Achievements are not supported by this game');
     }
     return await meta;
   }
 
   private async validity(): Promise<Validity> {
     return {
-      // Note: will need updating when we support non-EVM data availability layers.
+      // TODO: will need updating when we support non-EVM data availability layers.
       caip2: `eip155:${ENV.CHAIN_ID}`,
       block: await EngineService.INSTANCE.getSM().latestProcessedBlockHeight(),
       time: new Date().toISOString(),
     };
   }
 
+  @Response<FailedResult>(StatusCodes.NOT_IMPLEMENTED)
+  @Response<InternalServerErrorResult>(StatusCodes.INTERNAL_SERVER_ERROR)
+  @Response<ValidateErrorResult>(StatusCodes.UNPROCESSABLE_ENTITY)
   @Get('public/list')
   public async public_list(
     @Query() category?: string,
@@ -78,6 +87,8 @@ export class AchievementsController extends Controller {
     };
   }
 
+  @Response<InternalServerErrorResult>(StatusCodes.INTERNAL_SERVER_ERROR)
+  @Response<ValidateErrorResult>(StatusCodes.UNPROCESSABLE_ENTITY)
   @Get('wallet/{wallet}')
   public async wallet(
     @Path() wallet: string,
@@ -115,6 +126,10 @@ export class AchievementsController extends Controller {
     };
   }
 
+  @Response<FailedResult>(StatusCodes.NOT_FOUND)
+  @Response<FailedResult>(StatusCodes.NOT_IMPLEMENTED)
+  @Response<InternalServerErrorResult>(StatusCodes.INTERNAL_SERVER_ERROR)
+  @Response<ValidateErrorResult>(StatusCodes.UNPROCESSABLE_ENTITY)
   @Get('erc/{erc}/{cde}/{token_id}')
   public async nft(
     @Path() erc: string,
@@ -131,12 +146,12 @@ export class AchievementsController extends Controller {
           return await this.wallet(wallet, name);
         } else {
           // Future improvement: throw a different error if no CDE with that name exists
-          this.setStatus(404);
+          this.setStatus(StatusCodes.NOT_FOUND);
           throw new Error('No owner for that NFT');
         }
       // Future improvement: erc6551
       default:
-        this.setStatus(404);
+        this.setStatus(StatusCodes.NOT_IMPLEMENTED);
         throw new Error(`No support for /erc/${erc}`);
     }
   }