Merge pull request #2079 from AleoHQ/example/broken_bank

Add `broken_bank` example.

.circleci/test-examples.sh

@@ -4,6 +4,17 @@
   $LEO run main
 )
 
+# Build and run the broken_bank Leo program.
+(
+  cd ./project/examples/broken_bank || exit
+  $LEO run issue
+  $LEO run deposit
+  $LEO run withdraw
+
+  chmod +x ./run.sh
+  ./run.sh
+)
+
 # Build and run the bubblesort Leo program.
 (
   cd ./project/examples/bubblesort || exit

examples/broken_bank/.gitignore

@@ -0,0 +1,2 @@
+outputs/
+build/

examples/broken_bank/README.md

@@ -0,0 +1,8 @@
+# bank.aleo
+
+## Build Guide
+
+To compile this Aleo program, run:
+```bash
+aleo build
+```

examples/broken_bank/inputs/bank.in

@@ -0,0 +1,20 @@
+// The program input for broken_bank/src/main.leo
+[issue]
+owner: address = aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a;
+amount: u64 = 1234u64;
+
+[deposit]
+token: Token = Token {
+    owner: aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a,
+    gates: 0u64,
+    amount: 1234u64,
+    _nonce: 0group,
+};
+amount: u64 = 321u64;
+
+[withdraw]
+recipient: address = aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a;
+amount: u64 = 321u64;
+rate: u64 = 1500u64;
+periods: u64 = 10u64;
+

examples/broken_bank/program.json

@@ -0,0 +1,10 @@
+{
+  "program": "bank.aleo",
+  "version": "0.0.0",
+  "description": "",
+  "development": {
+      "private_key": "APrivateKey1zkpHtqVWT6fSHgUMNxsuVf7eaR6id2cj7TieKY1Z8CP5rCD",
+      "address": "aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a"
+  },
+  "license": "MIT"
+}

examples/broken_bank/run.sh

@@ -0,0 +1,79 @@
+#!/bin/bash
+# First check that Leo is installed.
+if ! command -v leo &> /dev/null
+then
+    echo "leo is not installed."
+    exit
+fi
+
+# The private key and address of the bank.
+# Swap these into program.json, when running transactions as the first bidder.
+# "private_key": "APrivateKey1zkpHtqVWT6fSHgUMNxsuVf7eaR6id2cj7TieKY1Z8CP5rCD",
+# "address": "aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a"
+
+# The private key and address of the user.
+# Swap these into program.json, when running transactions as the second bidder.
+# "private_key": "APrivateKey1zkp75cpr5NNQpVWc5mfsD9Uf2wg6XvHknf82iwB636q3rtc"
+# "address": "aleo1zeklp6dd8e764spe74xez6f8w27dlua3w7hl4z2uln03re52egpsv46ngg"
+
+# Swap in the private key and address of the bank to program.json.
+echo "{
+  \"program\": \"bank.aleo\",
+  \"version\": \"0.0.0\",
+  \"description\": \"\",
+  \"development\": {
+      \"private_key\": \"APrivateKey1zkpHtqVWT6fSHgUMNxsuVf7eaR6id2cj7TieKY1Z8CP5rCD\",
+      \"address\": \"aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a\"
+  },
+  \"license\": \"MIT\"
+}" > program.json
+
+# Have the bank issue 100 tokens to the user.
+echo "
+
+
+The bank is issuing 100 tokens to the user."
+leo run issue aleo1zeklp6dd8e764spe74xez6f8w27dlua3w7hl4z2uln03re52egpsv46ngg 100u64;
+
+# Swap in the private key and address of the user to program.json.
+echo "{
+  \"program\": \"bank.aleo\",
+  \"version\": \"0.0.0\",
+  \"description\": \"\",
+  \"development\": {
+      \"private_key\": \"APrivateKey1zkp75cpr5NNQpVWc5mfsD9Uf2wg6XvHknf82iwB636q3rtc\",
+      \"address\": \"aleo1zeklp6dd8e764spe74xez6f8w27dlua3w7hl4z2uln03re52egpsv46ngg\"
+  },
+  \"license\": \"MIT\"
+}" > program.json
+
+# Have the user deposit 50 tokens into the bank.
+echo "
+
+
+The user is depositing 50 tokens into the bank."
+leo run deposit "{
+    owner: aleo1zeklp6dd8e764spe74xez6f8w27dlua3w7hl4z2uln03re52egpsv46ngg.private,
+    gates: 0u64.private,
+    amount: 100u64.private,
+    _nonce: 4668394794828730542675887906815309351994017139223602571716627453741502624516group.public
+}"  50u64
+
+# Swap in the private key and address of the bank to program.json.
+echo "{
+  \"program\": \"bank.aleo\",
+  \"version\": \"0.0.0\",
+  \"description\": \"\",
+  \"development\": {
+      \"private_key\": \"APrivateKey1zkpHtqVWT6fSHgUMNxsuVf7eaR6id2cj7TieKY1Z8CP5rCD\",
+      \"address\": \"aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a\"
+  },
+  \"license\": \"MIT\"
+}" > program.json
+
+# Have the bank withdraw all of the user's tokens with compound interest over 15 periods at 12.34%.
+echo "
+
+
+The bank is withdrawing the user's tokens after 75 periods."
+leo run withdraw aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a 50u64 1234u64 15u64;

examples/broken_bank/src/main.leo

@@ -0,0 +1,75 @@
+record Token {
+    owner: address,
+    gates: u64,
+    amount: u64,
+}
+
+mapping balances: field => u64;
+
+@program
+function issue(owner: address, amount: u64) -> Token {
+    console.assert_eq(self.caller, aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a);
+    return Token {
+        owner: owner,
+        gates: 0u64,
+        amount: amount,
+    };
+}
+
+@program
+function deposit(token: Token, amount: u64) -> Token {
+    let difference: u64 = token.amount - amount;
+
+    let remaining: Token = Token {
+        owner: token.owner,
+        gates: token.gates,
+        amount: difference,
+    };
+
+    let hash: field = BHP256::hash(token.owner);
+
+    finalize(hash, amount);
+
+    return remaining;
+}
+
+finalize deposit(hash: field, amount: u64) {
+    increment(balances, hash, amount);
+}
+
+@program
+function withdraw(recipient: address, amount: u64, rate: u64, periods: u64) -> Token {
+    console.assert_eq(self.caller, aleo1t0uer3jgtsgmx5tq6x6f9ecu8tr57rzzfnc2dgmcqldceal0ls9qf6st7a);
+    let hash: field = BHP256::hash(recipient);
+
+    let total: u64 = calculate_interest(amount, rate, periods);
+
+    let token: Token = Token {
+        owner: recipient,
+        gates: 0u64,
+        amount: total,
+    };
+
+    finalize(hash, amount);
+
+    return token;
+}
+
+finalize withdraw(hash: field, amount: u64) {
+    decrement(balances, hash, amount);
+}
+
+function calculate_interest(principal: u64, rate: u64, periods: u64) -> u64 {
+    let amount: u64 = principal;
+
+    for i:u64 in 0u64..100u64 {
+        if i < periods {
+            amount += (amount * rate) / 10000u64;
+        }
+    }
+
+    return amount;
+}
+
+
+