Added doc for invokeContract

README.md

@@ -913,6 +913,46 @@ const name = instanceInfo.name;
 
 Note that only version 0 contracts returns the model. (use `isInstanceInfoV0`/`isInstanceInfoV1` to check the version)
 
+## InvokeContract
+Used to simulate a contract update, and to trigger view functions.
+
+```js
+const blockHash = "7f7409679e53875567e2ae812c9fcefe90ced8961d08554756f42bf268a42749";
+const contractAddress = { index: 1n, subindex: 0n };
+const invoker = new AccountAddress('3tXiu8d4CWeuC12irAB7YVb1hzp3YxsmmmNzzkdujCPqQ9EjDm');
+const result = await client.invokeContract(
+    blockHash,
+    {
+        invoker: invoker,
+        contract: contractAddress,
+        method: 'PiggyBank.smash',
+        amount: undefined,
+        parameter: undefined,
+        energy: 30000n,
+    }
+);
+
+if (!result) {
+    // The node could not attempt the invocation, most likely the contract doesn't exist.
+}
+
+if (result.tag === 'failure') {
+    // Invoke was unsuccesful
+    const rejectReason = result.reason; // Describes why the update failed;
+    ...
+} else {
+    const events = result.events; // a list of events that would be generated by the update
+    const returnValue = result.returnValue; // If the invoked method has return value
+    ...
+}
+```
+
+Note that some of the parts of the context are optional:
+ - amount: defaults to 0
+ - energy: defaults to 10 million
+ - parameter: defaults to no parameters
+ - invoker: uses the zero account address, which can be used instead of finding a random address.
+
 ## Deserialize contract state
 The following example demonstrates how to deserialize a contract's state:
 

src/client.ts

@@ -805,6 +805,12 @@ export default class ConcordiumNodeClient {
         return response;
     }
 
+    /**
+     * Simulates a smart contract update, and returns the updated state of smart contract instance (if V0 contract) or returnValue of the invoked method (if the method has a return value)  .
+     * @param blockHash the block hash at which the contract should be invoked at.
+     * @param context the collection of details used to invoke the contract. Must include the address of the contract and the method invoked.
+     * @returns If the node was able to invoke, then the outcome is returned. If the contract is not defined at the given block hash, then undefined is returned.
+     */
     async invokeContract(
         blockHash: string,
         contractContext: ContractContext