Merge pull request #2076 from AleoHQ/example/auction

Update auction example.

.circleci/test-examples.sh

@@ -1,7 +1,12 @@
 # Build and run the auction Leo program.
 (
   cd ./project/examples/auction || exit
-  $LEO run main
+  $LEO run place_bid
+  $LEO run resolve
+  $LEO run finish
+
+  chmod +x ./run.sh
+  ./run.sh
 )
 
 # Build and run the broken_bank Leo program.

examples/auction/inputs/auction.in

@@ -1,11 +1,42 @@
 // The program input for auction/src/main.leo
-[main]
+[place_bid]
-current: Auction = Auction {
+// Note that `bidder` must have the same address as the caller (refer to `program.json`).
+//   Swapping the below lines, will result in an error.
+// bidder: address = aleo1y7065c2jxkra5yzu9jfxq55klweqev0zas89lt9nxmfrqrafmq9qw2ktdg;
+bidder: address = aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh;
+amount: u64 = 90u64;
+
+[resolve]
+first: Bid = Bid {
      owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
      gates: 0u64,
-    winning_bidder: aleo1mgfq6g40l6zkhsm063n3uhr43qk5e0zsua5aszeq5080dsvlcvxsn0rrau,
+     bidder: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
-    winning_bid: 50u64,
+     amount: 10u64,
-    _nonce: 0group
+     is_winner: false,
+     _nonce: 6480683131255842390406647532838179519970794442201387718334686863304493823461group,
 };
-bidder: address = aleo1ht2a9q0gsd38j0se4t9lsfulxgqrens2vgzgry3pkvs93xrrzu8s892zn7;
+second: Bid = Bid {
-bid: u64 = 100u64;
+    owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
+    gates: 0u64,
+    bidder: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
+    amount: 90u64,
+    is_winner: false,
+    _nonce: 1635474322959998727812727786860193861506102794050195384593971440884677453921group,
+};
+
+[finish]
+bid: Bid = Bid {
+    owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
+    gates: 0u64,
+    bidder: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
+    amount: 90u64,
+    is_winner: false,
+    _nonce: 4195536711021629817871261453343069023119119274215827022954896024118351555272group,
+};
+
+
+
+
+
+
+

examples/auction/run.sh

@@ -0,0 +1,115 @@
+#!/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 first bidder.
+# Swap these into program.json, when running transactions as the first bidder.
+# "private_key": "APrivateKey1zkpG9Af9z5Ha4ejVyMCqVFXRKknSm8L1ELEwcc4htk9YhVK"
+# "address": aleo1yzlta2q5h8t0fqe0v6dyh9mtv4aggd53fgzr068jvplqhvqsnvzq7pj2ke
+
+# The private key and address of the second bidder.
+# Swap these into program.json, when running transactions as the second bidder.
+# "private_key": "APrivateKey1zkpAFshdsj2EqQzXh5zHceDapFWVCwR6wMCJFfkLYRKupug"
+# "address": aleo1esqchvevwn7n5p84e735w4dtwt2hdtu4dpguwgwy94tsxm2p7qpqmlrta4
+
+# The private key and address of the auctioneer.
+# Swap these into program.json, when running transactions as the auctioneer.
+# "private_key": "APrivateKey1zkp5wvamYgK3WCAdpBQxZqQX8XnuN2u11Y6QprZTriVwZVc",
+# "address": "aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh"
+
+# Swap in the private key and address of the first bidder to program.json.
+echo "{
+  \"program\": \"auction.aleo\",
+  \"version\": \"0.0.0\",
+  \"description\": \"\",
+  \"development\": {
+      \"private_key\": \"APrivateKey1zkpG9Af9z5Ha4ejVyMCqVFXRKknSm8L1ELEwcc4htk9YhVK\",
+      \"address\": \"aleo1yzlta2q5h8t0fqe0v6dyh9mtv4aggd53fgzr068jvplqhvqsnvzq7pj2ke\"
+  },
+  \"license\": \"MIT\"
+}" > program.json
+
+# Have the first bidder place a bid of 10.
+echo "
+
+
+The first bidder is placing a bid of 10."
+leo run place_bid aleo1yzlta2q5h8t0fqe0v6dyh9mtv4aggd53fgzr068jvplqhvqsnvzq7pj2ke 10u64
+
+# Swap in the private key and address of the second bidder to program.json.
+echo "{
+  \"program\": \"auction.aleo\",
+  \"version\": \"0.0.0\",
+  \"description\": \"\",
+  \"development\": {
+      \"private_key\": \"APrivateKey1zkpAFshdsj2EqQzXh5zHceDapFWVCwR6wMCJFfkLYRKupug\",
+      \"address\": \"aleo1esqchvevwn7n5p84e735w4dtwt2hdtu4dpguwgwy94tsxm2p7qpqmlrta4\"
+  },
+  \"license\": \"MIT\"
+}" > program.json
+
+
+# Have the second bidder place a bid of 90.
+echo "
+
+
+The second bidder is placing a bid of 90."
+leo run place_bid aleo1esqchvevwn7n5p84e735w4dtwt2hdtu4dpguwgwy94tsxm2p7qpqmlrta4 90u64
+
+# Swap in the private key and address of the auctioneer to program.json.
+echo "{
+  \"program\": \"auction.aleo\",
+  \"version\": \"0.0.0\",
+  \"description\": \"\",
+  \"development\": {
+      \"private_key\": \"APrivateKey1zkp5wvamYgK3WCAdpBQxZqQX8XnuN2u11Y6QprZTriVwZVc\",
+      \"address\": \"aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh\"
+  },
+  \"license\": \"MIT\"
+}" > program.json
+
+# Have the auctioneer select the winning bid.
+
+echo "
+
+
+The auctioneer is selecting the winning bid."
+leo run resolve "{
+        owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh.private,
+        gates: 0u64.private,
+        bidder: aleo1yzlta2q5h8t0fqe0v6dyh9mtv4aggd53fgzr068jvplqhvqsnvzq7pj2ke.private,
+        amount: 10u64.private,
+        is_winner: false.private,
+        _nonce: 4668394794828730542675887906815309351994017139223602571716627453741502624516group.public
+    }" "{
+        owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh.private,
+        gates: 0u64.private,
+        bidder: aleo1esqchvevwn7n5p84e735w4dtwt2hdtu4dpguwgwy94tsxm2p7qpqmlrta4.private,
+        amount: 90u64.private,
+        is_winner: false.private,
+        _nonce: 5952811863753971450641238938606857357746712138665944763541786901326522216736group.public
+    }"
+
+# Have the auctioneer finish the auction.
+echo "
+
+
+The auctioneer is finishing the auction."
+leo run finish "{
+        owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh.private,
+        gates: 0u64.private,
+        bidder: aleo1esqchvevwn7n5p84e735w4dtwt2hdtu4dpguwgwy94tsxm2p7qpqmlrta4.private,
+        amount: 90u64.private,
+        is_winner: false.private,
+        _nonce: 5952811863753971450641238938606857357746712138665944763541786901326522216736group.public
+    }"
+
+
+
+
+
+

examples/auction/src/main.leo

@@ -1,54 +1,53 @@
-// This example is suggestive of an auction smart contract,
+// This record defines a bid in the auction.
-// but it is much simpler of a full auction smart contract.
+record Bid {
-
-// This is a record that contains the current state of the auction,
-// which in this example just consists of
-// the address of the currently winning bidder
-// and the currently winning amount.
-// The owner and gates fields are required in a record;
-// the owner address in general differs from the current auction winner:
-// the owner is the one running the auction itself.
-
-record Auction {
     owner: address,
     gates: u64,
-    winning_bidder: address,
+    bidder: address,
-    winning_bid: u64
+    amount: u64,
+    is_winner: bool,
 }
 
-// This function realizes the checking and possible incorporation of a new bid.
+// This function creates a new bid.
-// Unlike a traditional auction, where the currently winning bid is known,
+// This function checks that `bidder` invoked the function.
-// and only higher bids would be normally brought up in the room,
+// Note that the owner of the record is set to the entity responsible for running the auction.
-// in a zero-knowledge context presumably bidding is blind,
+//   The entity's address is aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh.
-// i.e. a bidder does not know the currently highest bid.
+//   This is necessary to allow the entity running the auction to process bids.
-// Thus, this function represents a possible update of the auction state
-// with a new bid:
-// if the amount exceeds the currently winning one,
-// the record is updated with the new bid and the new bidder's address;
-// the latter is also passed as input.
-// Again, this is just a simple example;
-// in a serious auction smart contract,
-// there will be some additional checks,
-// and presumably ways to tie bidder and amount (e.g. commitments).
-//
-// In order to run this function, an Auction record must be passed to it.
-// This is done in the input file, inputs/auction.in.
-// Note that, when building that record,
-// the owner address must be the same as the one in the program.json file.
-
 @program
-function main(current: Auction, bidder: address, bid: u64) -> Auction {
+function place_bid(bidder: address, amount: u64) -> Bid {
-    let winning_bidder: address = current.winning_bidder;
+    console.assert_eq(self.caller, bidder);
-    let winning_bid: u64 = current.winning_bid;
+    return Bid {
-    if bid > current.winning_bid {
+        owner: aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh,
-        winning_bidder = bidder;
+        gates: 0u64,
-        winning_bid = bid;
+        bidder: bidder,
-    }
+        amount: amount,
-    let new: Auction = Auction {
+        is_winner: false,
-        owner: current.owner,
+    };
-        gates: current.gates,
+}
-        winning_bidder: winning_bidder,
+
-        winning_bid: winning_bid
+// This function consumes two bids, selecting the winning one. In the event of a tie, the first bid is selected.
+// This function should be invoked once the bidding period has ended.
+// This function can only be called by the entity running the auction.
+@program
+function resolve(first: Bid, second: Bid) -> Bid {
+    console.assert_eq(self.caller, aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh);
+    if (first.amount >= second.amount) {
+        return first;
+    } else {
+        return second;
+    }
+}
+
+// This function returns ownership of the `Bid` record to the original bidder.
+// This function should be called after all bids have been resolved.
+// This function can only be called by the entity running the auction.
+@program
+function finish(bid: Bid) -> Bid {
+    console.assert_eq(self.caller, aleo1fxs9s0w97lmkwlcmgn0z3nuxufdee5yck9wqrs0umevp7qs0sg9q5xxxzh);
+    return Bid {
+        owner: bid.bidder,
+        gates: bid.gates,
+        bidder: bid.bidder,
+        amount: bid.amount,
+        is_winner: true,
     };
-    return new;
 }