[contract] Add statistics variables

blockchain/contracts/PoBA.sol

@@ -26,9 +26,14 @@ contract PoBA {
 
   mapping (address => User) public users;
 
+  // Stats:
+  uint64 public totalUsers;
+  uint64 public totalBankAccounts;
+
   // Events:
   event LogBankAccountRegistered(address indexed wallet, bytes32 keccakIdentifier);
   event LogBankAccountUnregistered(address indexed wallet, bytes32 keccakIdentifier);
+  event LogSignerChanged(address newSigner);
 
   // Modifiers:
   modifier onlyOwner() {
@@ -60,6 +65,7 @@ contract PoBA {
   // and on contract-side to verify them
   function setSigner(address newSigner) public onlyOwner {
     signer = newSigner;
+    emit LogSignerChanged(newSigner);
   }
 
   function register(
@@ -74,6 +80,7 @@ contract PoBA {
     if (!userExists(msg.sender)) {
       // new user
       users[msg.sender].creationBlock = block.number;
+      totalUsers += 1;
     }
 
     BankAccount memory ba;
@@ -85,15 +92,17 @@ contract PoBA {
     ba.creationBlock = block.number;
 
     bytes32 hash = keccak256(
-    abi.encodePacked(
-      msg.sender,
+      abi.encodePacked(
+        msg.sender,
         ba.accountNumber,
         ba.bankName
-    ));
+      )
+    );
     require(signerIsValid(hash, v, r, s));
     ba.keccakIdentifier = hash;
 
     users[msg.sender].bankAccounts.push(ba);
+    totalBankAccounts += 1;
 
     emit LogBankAccountRegistered(msg.sender, ba.keccakIdentifier);
   }
@@ -116,9 +125,11 @@ contract PoBA {
       users[msg.sender].bankAccounts[index] = users[msg.sender].bankAccounts[length - 1];
     }
     users[msg.sender].bankAccounts.length--;
+    totalBankAccounts -= 1;
 
     if (users[msg.sender].bankAccounts.length == 0) {
       delete users[msg.sender];
+      totalUsers -= 1;
     }
 
     emit LogBankAccountUnregistered(msg.sender, keccakIdentifier);

blockchain/test/poba.js

@@ -148,6 +148,42 @@ contract('bank account registration (success)', () => {
       assert.equal(+bankAccounts2, 1)
     })
   })
+
+  contract('', () => {
+    it("totalUsers should be incremented if it's the first bank account for that user", async () => {
+      const poba = await PoBA.deployed()
+
+      let users = await poba.totalUsers()
+      assert.equal(+users, 0)
+
+      const bankAccountData = {
+        account: '1111222233330000',
+        institution: 'Chase'
+      }
+      const args = buildRegisterBankAccountArgs(ethAccount[0], bankAccountData)
+      await registerBankAccount(poba, args, ethAccount[0])
+
+      users = await poba.totalUsers()
+      assert.equal(+users, 1)
+    })
+  })
+
+  contract('', () => {
+    it('should increment totalBankAccounts value', async () => {
+      const poba = await PoBA.deployed()
+      let totalBankAccounts = await poba.totalBankAccounts()
+      assert.equal(+totalBankAccounts, 0)
+
+      const accountData = {
+        account: '1111222233330001',
+        institution: 'Chase'
+      }
+      const args = buildRegisterBankAccountArgs(ethAccount[0], accountData)
+      await registerBankAccount(poba, args, ethAccount[0])
+      totalBankAccounts = await poba.totalBankAccounts()
+      assert.equal(+totalBankAccounts, 1)
+    })
+  })
 })
 
 contract('bank account registration (fail)', () => {
@@ -240,6 +276,29 @@ contract('bank account registration (fail)', () => {
       )
     })
   })
+
+  contract('', () => {
+    it('totalUsers should not be incremented if registerBankAccount fails', async () => {
+      const poba = await PoBA.deployed()
+
+      let totalUsers = await poba.totalUsers()
+      assert.equal(+totalUsers, 0)
+
+      // Make registerBankAccount fail with an emtpy institutuion
+      const bankAccountData = {
+        account: '1111222233330000',
+        institution: ''
+      }
+      const args = buildRegisterBankAccountArgs(ethAccount[0], bankAccountData)
+      await registerBankAccount(poba, args, ethAccount[0]).then(
+        () => assert.fail(), // should reject
+        async () => {
+          totalUsers = await poba.totalUsers()
+          assert.equal(+totalUsers, 0)
+        }
+      )
+    })
+  })
 })
 
 contract('bank account removal', accounts => {
@@ -366,6 +425,83 @@ contract('bank account removal', accounts => {
       assert.equal(+bankAccountCount, 1)
     })
   })
+
+  contract('', () => {
+    it('should decrement totalUsers value if the unregistered bank account was the only one for that user', async () => {
+      const poba = await PoBA.deployed()
+
+      let totalUsers = await poba.totalUsers()
+      assert.equal(+totalUsers, 0)
+
+      const bankAccountData = {
+        account: '1111222233330000',
+        institution: 'Chase'
+      }
+      const args = buildRegisterBankAccountArgs(accounts[0], bankAccountData)
+      await registerBankAccount(poba, args, accounts[0])
+      const bankAccountCount = await poba.accountsLength(accounts[0])
+      assert.equal(+bankAccountCount, 1)
+
+      totalUsers = await poba.totalUsers()
+      assert.equal(+totalUsers, 1)
+
+      await unregisterBankAccount(poba, args, accounts[0])
+
+      totalUsers = await poba.totalUsers()
+      assert.equal(+totalUsers, 0)
+    })
+  })
+
+  contract('', () => {
+    it('should not decrement totalUsers value if the unregistered bank account was not the only one for that user', async () => {
+      const poba = await PoBA.deployed()
+
+      let totalUsers = await poba.totalUsers()
+      assert.equal(+totalUsers, 0)
+      let bankAccounts = await poba.accountsLength(ethAccount[0])
+      assert.equal(+bankAccounts, 0)
+
+      const bankOne = {
+        account: '1111222233330000',
+        institution: 'Chase'
+      }
+      const bankTwo = {
+        account: '1111222233330001',
+        institution: 'Sugar'
+      }
+      const args1 = buildRegisterBankAccountArgs(ethAccount[0], bankOne)
+      await registerBankAccount(poba, args1, ethAccount[0])
+      const args2 = buildRegisterBankAccountArgs(ethAccount[0], bankTwo)
+      await registerBankAccount(poba, args2, ethAccount[0])
+      bankAccounts = await poba.accountsLength(ethAccount[0])
+      assert.equal(+bankAccounts, 2)
+
+      await unregisterBankAccount(poba, args1, ethAccount[0])
+
+      totalUsers = await poba.totalUsers()
+      assert.equal(+totalUsers, 1)
+    })
+  })
+
+  contract('', () => {
+    it('should decrement totalBankAccounts value', async () => {
+      const poba = await PoBA.deployed()
+      const accountData = {
+        account: '1111222233330001',
+        institution: 'Chase'
+      }
+      const args = buildRegisterBankAccountArgs(ethAccount[0], accountData)
+      await registerBankAccount(poba, args, ethAccount[0])
+
+      let totalBankAccounts = await poba.totalBankAccounts()
+      assert.equal(+totalBankAccounts, 1)
+
+      await unregisterBankAccount(poba, args, ethAccount[0])
+
+      totalBankAccounts = await poba.totalBankAccounts()
+      assert.equal(+totalBankAccounts, 0)
+    })
+  })
 })
 
 contract('setSigner', accounts => {