Add proof period and timeout to contract

contracts/StorageContract.sol

@@ -8,10 +8,14 @@ contract StorageContract {
   uint public immutable size; // storage size in bytes
   uint public immutable price; // price in coins
   address public immutable host; // host that provides storage
+  uint public immutable proofPeriod; // average time between proofs (in blocks)
+  uint public immutable proofTimeout; // proof has to be submitted before this
 
   constructor(uint _duration,
               uint _size,
               uint _price,
+              uint _proofPeriod,
+              uint _proofTimeout,
               address _host,
               bytes memory requestSignature,
               bytes memory bidSignature)
@@ -24,6 +28,8 @@ contract StorageContract {
     size = _size;
     price = _price;
     host = _host;
+    proofPeriod = _proofPeriod;
+    proofTimeout = _proofTimeout;
   }
 
   // creates hash for a storage request that can be used to check its signature

test/StorageContract.test.js

@@ -4,8 +4,10 @@ const { hashRequest, hashBid, sign } = require("./marketplace")
 
 describe("Storage Contract", function () {
 
-  const duration = 31 * 24 * 60 * 60
-  const size = 1 * 1024 * 1024 * 1024
+  const duration = 31 * 24 * 60 * 60 // 31 days
+  const size = 1 * 1024 * 1024 * 1024 // 1 Gigabyte
+  const proofPeriod = 64 // 64 blocks ≈ 15 minutes
+  const proofTimeout = 42 // 42 blocks ≈ 10 minutes
   const price = 42
 
   var StorageContract
@@ -27,6 +29,8 @@ describe("Storage Contract", function () {
         duration,
         size,
         price,
+        proofPeriod,
+        proofTimeout,
         await host.getAddress(),
         await sign(client, requestHash),
         await sign(host, bidHash)
@@ -49,6 +53,13 @@ describe("Storage Contract", function () {
       expect(await contract.host()).to.equal(await host.getAddress())
     })
 
+    it("has an average time between proofs (in blocks)", async function (){
+      expect(await contract.proofPeriod()).to.equal(proofPeriod)
+    })
+
+    it("has a proof timeout (in blocks)", async function (){
+      expect(await contract.proofTimeout()).to.equal(proofTimeout)
+    })
   })
 
   it("cannot be created when client signature is invalid", async function () {
@@ -57,6 +68,8 @@ describe("Storage Contract", function () {
       duration,
       size,
       price,
+      proofPeriod,
+      proofTimeout,
       await host.getAddress(),
       invalidSignature,
       await sign(host, bidHash)
@@ -69,6 +82,8 @@ describe("Storage Contract", function () {
       duration,
       size,
       price,
+      proofPeriod,
+      proofTimeout,
       await host.getAddress(),
       await sign(client, requestHash),
       invalidSignature