From 01c4e3c506aa6fd09472d53ed0cd4af2a364d034 Mon Sep 17 00:00:00 2001
From: "nkl199@yahoo.co.uk" <nkl199@yahoo.co.uk>
Date: Mon, 9 Sep 2019 15:18:05 +0100
Subject: [PATCH] add a query smart contract method

Signed-off-by: nkl199@yahoo.co.uk <nkl199@yahoo.co.uk>
---
 .../caliper-core/lib/blockchain-interface.js  | 14 +++++++-
 packages/caliper-core/lib/blockchain.js       | 33 ++++++++++++++++++-
 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/packages/caliper-core/lib/blockchain-interface.js b/packages/caliper-core/lib/blockchain-interface.js
index 4be10dae5..afe5dfe51 100644
--- a/packages/caliper-core/lib/blockchain-interface.js
+++ b/packages/caliper-core/lib/blockchain-interface.js
@@ -81,12 +81,24 @@ class BlockchainInterface {
      * @param {String} contractID identity of the contract
      * @param {String} contractVer version of the contract
      * @param {Array} args array of JSON formatted arguments for multiple transactions
-     * @param {Number} timeout request timeout, in second
+     * @param {Number} timeout request timeout, in seconds
      */
     async invokeSmartContract(context, contractID, contractVer, args, timeout) {
         throw new Error('invokeSmartContract is not implemented for this blockchain system');
     }
 
+    /**
+     * Query state from the ledger using a smart contract
+     * @param {Object} context context object
+     * @param {String} contractID identity of the contract
+     * @param {String} contractVer version of the contract
+     * @param {Array} args array of JSON formatted arguments
+     * @param {Number} timeout request timeout, in seconds
+     */
+    async querySmartContract(context, contractID, contractVer, args, timeout) {
+        throw new Error('querySmartContract is not implemented for this blockchain system');
+    }
+
     /**
      * Query state from the ledger
      * @param {Object} context context object from getContext
diff --git a/packages/caliper-core/lib/blockchain.js b/packages/caliper-core/lib/blockchain.js
index f003beffa..057c7996d 100644
--- a/packages/caliper-core/lib/blockchain.js
+++ b/packages/caliper-core/lib/blockchain.js
@@ -114,6 +114,37 @@ class Blockchain {
         return await this.bcObj.invokeSmartContract(context, contractID, contractVer, arg, time);
     }
 
+    /**
+     * Query state from the ledger using a smart contract
+     * @param {Object} context context object
+     * @param {String} contractID identiy of the contract
+     * @param {String} contractVer version of the contract
+     * @param {Array} args array of JSON formatted arguments
+     * @param {Number} timeout request timeout, in seconds
+     * @return {Promise} query response object
+     */
+    async querySmartContract(context, contractID, contractVer, args, timeout) {
+        let arg, time;
+        if(Array.isArray(args)) {
+            arg = args;
+        }
+        else if(typeof args === 'object') {
+            arg = [args];
+        }
+        else {
+            throw new Error('Invalid args for querySmartContract()');
+        }
+
+        if(typeof timeout !== 'number' || timeout < 0) {
+            time = 120;
+        }
+        else {
+            time = timeout;
+        }
+
+        return await this.bcObj.querySmartContract(context, contractID, contractVer, arg, time);
+    }
+
     /**
      * Query state from the ledger
      * @param {Object} context context object from getContext
@@ -121,7 +152,7 @@ class Blockchain {
      * @param {String} contractVer version of the contract
      * @param {String} key lookup key
      * @param {String=} [fcn] query function name
-     * @return {Promise} as invokeSmateContract()
+     * @return {Object} as invokeSmateContract()
      */
     async queryState(context, contractID, contractVer, key, fcn) {
         return await this.bcObj.queryState(context, contractID, contractVer, key, fcn);