feat(provider): preparation for the fee integration

src/provider/default.ts

@@ -81,7 +81,7 @@ export class Provider implements ProviderInterface {
   }
 
   private getFetchMethod(endpoint: keyof Endpoints) {
-    const postMethodEndpoints = ['add_transaction', 'call_contract'];
+    const postMethodEndpoints = ['add_transaction', 'call_contract', 'estimate_fee'];
 
     return postMethodEndpoints.includes(endpoint) ? 'POST' : 'GET';
   }
@@ -333,6 +333,17 @@ export class Provider implements ProviderInterface {
     });
   }
 
+  public estimateFee(invocation: Invocation): Promise<any> {
+    return this.fetchEndpoint('estimate_fee', undefined, {
+      // TODO: change the TYPE of the call
+      type: 'INVOKE_FUNCTION',
+      contract_address: invocation.contractAddress,
+      entry_point_selector: getSelectorFromName(invocation.entrypoint),
+      calldata: bigNumberishArrayToDecimalStringArray(invocation.calldata ?? []),
+      signature: bigNumberishArrayToDecimalStringArray(invocation.signature ?? []),
+    });
+  }
+
   public async waitForTransaction(txHash: BigNumberish, retryInterval: number = 8000) {
     let onchain = false;
     await wait(retryInterval);

src/types/api.ts

@@ -67,6 +67,11 @@ export type Endpoints = {
     REQUEST: CallContractTransaction;
     RESPONSE: CallContractResponse;
   };
+  estimate_fee: {
+    QUERY: never;
+    REQUEST: Transaction;
+    RESPONSE: EstimateFeeResponse;
+  };
 };
 
 export type GetContractAddressesResponse = {
@@ -168,6 +173,8 @@ export type TransactionReceipt = {
   l2_to_l1_messages: string[];
   events: string[];
 };
+// TODO: Add response data
+export type EstimateFeeResponse = {};
 
 export type RawArgs = {
   [inputName: string]: string | string[] | { type: 'struct'; [k: string]: BigNumberish };

src/types/lib.ts

@@ -70,3 +70,7 @@ export type CompiledContract = {
 export type CompressedCompiledContract = Omit<CompiledContract, 'program'> & {
   program: CompressedProgram;
 };
+
+export type ParsedStruct = {
+  [key: string]: BigNumberish | ParsedStruct;
+};

src/utils/transaction.ts

@@ -1,5 +1,4 @@
-import { ParsedStruct } from '../contract';
-import { Call } from '../types';
+import { Call, ParsedStruct } from '../types';
 import { getSelectorFromName } from './hash';
 import { BigNumberish, bigNumberishArrayToDecimalStringArray, toBN } from './number';