feat: added a new endpoint fee_rate #729

docs/api/info/get-fee-rate-request.example.json

@@ -0,0 +1,3 @@
+{
+  "transaction": "0x5e9f3933e358df6a73fec0d47ce3e1062c20812c129f5294e6f37a8d27c051d9"
+}

docs/api/info/get-fee-rate-request.schema.json

@@ -0,0 +1,15 @@
+{
+  "type": "object",
+  "title": "FeeRateRequest",
+  "description": "Request to fetch fee for a transaction",
+  "additionalProperties": false,
+  "required": [
+    "transaction"
+  ],
+  "properties": {
+    "transaction": {
+      "type": "string",
+      "description": "A serialized transaction"
+    }
+  }
+}

docs/api/info/get-fee-rate-response.example.json

@@ -0,0 +1,3 @@
+{
+  "fee_rate": 360
+}

docs/api/info/get-fee-rate-response.schema.json

@@ -0,0 +1,14 @@
+{
+  "title": "FeeRate",
+  "description": "Get fee rate information.",
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "fee_rate"
+  ],
+  "properties": {
+    "fee_rate": {
+      "type": "integer"
+    }
+  }
+}

docs/generated.d.ts

@@ -37,6 +37,8 @@ export type SchemaMergeRootStub =
   | CoreNodeInfoResponse
   | CoreNodePoxResponse
   | RunFaucetResponse
+  | FeeRateRequest
+  | FeeRate
   | NetworkBlockTimeResponse
   | NetworkBlockTimesResponse
   | ServerStatusResponse
@@ -1562,6 +1564,21 @@ export interface RunFaucetResponse {
    */
   txRaw?: string;
 }
+/**
+ * Request to fetch fee for a transaction
+ */
+export interface FeeRateRequest {
+  /**
+   * A serialized transaction
+   */
+  transaction: string;
+}
+/**
+ * Get fee rate information.
+ */
+export interface FeeRate {
+  fee_rate: number;
+}
 /**
  * GET request that target block time for a given network
  */

docs/openapi.yaml

@@ -1083,7 +1083,7 @@ paths:
           in: path
           description: Stacks address or a contract identifier
           required: true
-          schema: 
+          schema:
             type: string
         - name: tx_id
           in: path
@@ -1556,7 +1556,7 @@ paths:
           content:
             application/json:
               schema:
-                $ref: ./api/search/search.schema.json 
+                $ref: ./api/search/search.schema.json
               example:
                 $ref: ./api/search/search-contract.example.json
         404:
@@ -2659,3 +2659,28 @@ paths:
                 $ref: ./entities/tokens/fungible-token.schema.json
               example:
                 $ref: ./entities/tokens/fungible-token.schema.example.json
+
+  /extended/v1/fee_rate:
+    post:
+      operationId: fetch_fee_rate
+      summary: fetch fee rate
+      description: Fetch fee rate information.
+      tags:
+        - fee_rate
+      responses:
+        200:
+          description: Transaction fee rate
+          content:
+            application/json:
+              schema:
+                $ref: ./api/info/get-fee-rate-response.schema.json
+              example:
+                $ref: ./api/info/get-fee-rate-response.example.json
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: ./api/info/get-fee-rate-request.schema.json
+            example:
+              $ref: ./api/info/get-fee-rate-request.example.json

src/api/init.ts

@@ -42,6 +42,7 @@ import { createMiddleware as createPrometheusMiddleware } from '@promster/expres
 import { createMicroblockRouter } from './routes/microblock';
 import { createStatusRouter } from './routes/status';
 import { createTokenRouter } from './routes/tokens/tokens';
+import { createFeeRateRouter } from './routes/fee-rate';
 
 export interface ApiServer {
   expressApp: ExpressWithAsync;
@@ -152,6 +153,7 @@ export async function startApiServer(opts: {
       router.use('/stx_supply', createStxSupplyRouter(datastore));
       router.use('/debug', createDebugRouter(datastore));
       router.use('/status', createStatusRouter(datastore));
+      router.use('/fee_rate', createFeeRateRouter(datastore));
       router.use('/faucets', createFaucetRouter(datastore));
       router.use('/tokens', createTokenRouter(datastore));
       return router;

src/api/routes/fee-rate.ts

@@ -0,0 +1,20 @@
+import * as express from 'express';
+import { addAsync, RouterWithAsync } from '@awaitjs/express';
+import { DataStore } from '../../datastore/common';
+import { FeeRate } from '@stacks/stacks-blockchain-api-types';
+
+export const FEE_RATE = 400;
+
+export function createFeeRateRouter(_: DataStore): RouterWithAsync {
+  const router = addAsync(express.Router());
+
+  router.post('/', (req, res) => {
+    //validate and use req.body.transaction when we want to use it
+    const response: FeeRate = {
+      fee_rate: FEE_RATE,
+    };
+    res.json(response);
+  });
+
+  return router;
+}

src/tests/api-tests.ts

@@ -42,6 +42,8 @@ import { startApiServer, ApiServer } from '../api/init';
 import { PgDataStore, cycleMigrations, runMigrations } from '../datastore/postgres-store';
 import { PoolClient } from 'pg';
 import { bufferToHexPrefixString, I32_MAX, microStxToStx, STACKS_DECIMAL_PLACES } from '../helpers';
+import { FEE_RATE } from './../api/routes/fee-rate';
+import { FeeRateRequest } from 'docs/generated';
 
 describe('api tests', () => {
   let db: PgDataStore;
@@ -4998,6 +5000,16 @@ describe('api tests', () => {
     expect(result4.body.results.length).toBe(0);
   });
 
+  test('Get fee rate', async () => {
+    const request: FeeRateRequest = {
+      transaction: '0x5e9f3933e358df6a73fec0d47ce3e1062c20812c129f5294e6f37a8d27c051d9',
+    };
+    const result = await supertest(api.server).post('/extended/v1/fee_rate').send(request);
+    expect(result.status).toBe(200);
+    expect(result.type).toBe('application/json');
+    expect(result.body.fee_rate).toBe(FEE_RATE);
+  });
+
   afterEach(async () => {
     await api.terminate();
     client.release();