Remove optional 'from' field

src/accountant.rs

@@ -87,7 +87,7 @@ impl Accountant {
         }
 
         let event = Event::Transaction {
-            from: Some(from),
+            from,
             to,
             data,
             sig,

src/bin/client-demo.rs

@@ -45,7 +45,7 @@ fn main() {
     let now = Instant::now();
     for &(k, s) in &sigs {
         let e = Event::Transaction {
-            from: Some(alice_pubkey),
+            from: alice_pubkey,
             to: k,
             data: one,
             sig: s,

src/event.rs

@@ -30,7 +30,7 @@ pub type Signature = GenericArray<u8, U64>;
 pub enum Event<T> {
     Tick,
     Transaction {
-        from: Option<PublicKey>,
+        from: PublicKey,
         to: PublicKey,
         data: T,
         sig: Signature,
@@ -40,7 +40,7 @@ pub enum Event<T> {
 impl<T> Event<T> {
     pub fn new_claim(to: PublicKey, data: T, sig: Signature) -> Self {
         Event::Transaction {
-            from: Some(to),
+            from: to,
             to,
             data,
             sig,
@@ -75,7 +75,7 @@ pub fn sign_transaction_data<T: Serialize>(
     keypair: &Ed25519KeyPair,
     to: &PublicKey,
 ) -> Signature {
-    let from = &Some(get_pubkey(keypair));
+    let from = &get_pubkey(keypair);
     sign_serialized(&(from, to, data), keypair)
 }
 
@@ -111,7 +111,7 @@ pub fn verify_event<T: Serialize>(event: &Event<T>) -> bool {
     } = *event
     {
         let sign_data = serialize(&(&from, &to, &data)).unwrap();
-        if !verify_signature(&from.unwrap_or(to), &sign_data, &sig) {
+        if !verify_signature(&from, &sign_data, &sig) {
             return false;
         }
     }

src/genesis.rs

@@ -22,7 +22,7 @@ impl Creator {
     }
 
     pub fn create_transaction(&self, keypair: &Ed25519KeyPair) -> Event<u64> {
-        let from = Some(get_pubkey(keypair));
+        let from = get_pubkey(keypair);
         let to = self.pubkey;
         let data = self.tokens;
         let sig = sign_transaction_data(&data, keypair, &to);

src/log.rs

@@ -255,7 +255,7 @@ mod tests {
         let pubkey1 = get_pubkey(&keypair1);
         let data = hash(b"hello, world");
         let event0 = Event::Transaction {
-            from: Some(get_pubkey(&keypair0)),
+            from: get_pubkey(&keypair0),
             to: pubkey1,
             data,
             sig: sign_transaction_data(&data, &keypair0, &pubkey1),
@@ -272,7 +272,7 @@ mod tests {
         let pubkey1 = get_pubkey(&keypair1);
         let data = hash(b"hello, world");
         let event0 = Event::Transaction {
-            from: Some(get_pubkey(&keypair0)),
+            from: get_pubkey(&keypair0),
             to: pubkey1,
             data: hash(b"goodbye cruel world"), // <-- attack!
             sig: sign_transaction_data(&data, &keypair0, &pubkey1),
@@ -290,7 +290,7 @@ mod tests {
         let pubkey1 = get_pubkey(&keypair1);
         let data = hash(b"hello, world");
         let event0 = Event::Transaction {
-            from: Some(get_pubkey(&keypair0)),
+            from: get_pubkey(&keypair0),
             to: get_pubkey(&thief_keypair), // <-- attack!
             data: hash(b"goodbye cruel world"),
             sig: sign_transaction_data(&data, &keypair0, &pubkey1),