From 4d808cec194faf1df325ae78c5db87b5b9fd8d76 Mon Sep 17 00:00:00 2001
From: Jakub Nowakowski <jakub.nowakowski@akena.co>
Date: Tue, 16 Feb 2021 13:41:11 +0100
Subject: [PATCH 1/2] Gave generic name to event emitter in Deposit

The event emitter was renamed to a generic name, so it won't be
dedicated to just one type of event but it will be used for
different types of events.
---
 src/Deposit.js | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/src/Deposit.js b/src/Deposit.js
index 0d8ad56..48fd148 100644
--- a/src/Deposit.js
+++ b/src/Deposit.js
@@ -432,7 +432,7 @@ export default class Deposit {
       this.publicKeyPointToBitcoinAddress(point)
     )
 
-    this.receivedFundingConfirmationEmitter = new EventEmitter()
+    this.eventEmitter = new EventEmitter()
   }
 
   // /------------------------------- Accessors -------------------------------
@@ -507,14 +507,11 @@ export default class Deposit {
           transaction.transactionID,
           requiredConfirmations,
           ({ transactionID, confirmations, requiredConfirmations }) => {
-            this.receivedFundingConfirmationEmitter.emit(
-              "receivedFundingConfirmation",
-              {
-                transactionID,
-                confirmations,
-                requiredConfirmations
-              }
-            )
+            this.eventEmitter.emit("receivedFundingConfirmation", {
+              transactionID,
+              confirmations,
+              requiredConfirmations
+            })
           }
         )
 
@@ -628,7 +625,7 @@ export default class Deposit {
    *        confirmations, and requiredConfirmations as its parameter.
    */
   onReceivedFundingConfirmation(onReceivedFundingConfirmationHandler) {
-    this.receivedFundingConfirmationEmitter.on(
+    this.eventEmitter.on(
       "receivedFundingConfirmation",
       onReceivedFundingConfirmationHandler
     )

From e72df5e4696459edcdbf3aed113e22137c5e32c9 Mon Sep 17 00:00:00 2001
From: Jakub Nowakowski <jakub.nowakowski@akena.co>
Date: Tue, 16 Feb 2021 13:41:51 +0100
Subject: [PATCH 2/2] Error handler for Deposit autoSubmit errors

Previously when an error was returned from `provideBTCFundingProof`
transaction in the `autoSubmit` flow an UnhandledPromiseRejectionWarning
was logged, user of the library had no chance to handle this error.

As autoSubmit happens asynchronously we need a way to bubble up the
error. In this proposed approach we catch the error an emit it as an
event. User is required to define error callback with `onError` function.
---
 src/Deposit.js | 36 ++++++++++++++++++++++++++++++++----
 1 file changed, 32 insertions(+), 4 deletions(-)

diff --git a/src/Deposit.js b/src/Deposit.js
index 48fd148..c22c090 100644
--- a/src/Deposit.js
+++ b/src/Deposit.js
@@ -583,6 +583,34 @@ export default class Deposit {
     )
   }
 
+  // /---------------------------- Error Handler -----------------------------
+
+  /**
+   * Emits an event with an error.
+   *
+   * @param {Error} err Error to emit.
+   */
+  notifyError(err) {
+    this.eventEmitter.emit("error", err)
+  }
+
+  /**
+   * A handler that is notified whenever an error occurs.
+   *
+   * @callback OnErrorHandler
+   * @param {Error} err Error
+   */
+
+  /**
+   * Registers a handler for errors.
+   *
+   * @param {OnErrorHandler} onErrorHandler
+   *        A handler that receives an error.
+   */
+  onError(onErrorHandler) {
+    this.eventEmitter.on("error", onErrorHandler)
+  }
+
   // /---------------------------- Event Handlers -----------------------------
 
   /**
@@ -1000,8 +1028,8 @@ export default class Deposit {
     this.autoSubmittingState = {
       fundingTransaction: this.fundingTransaction,
       fundingConfirmations: this.fundingConfirmations,
-      proofTransaction: this.fundingConfirmations.then(
-        async ({ transaction, requiredConfirmations }) => {
+      proofTransaction: this.fundingConfirmations
+        .then(async ({ transaction, requiredConfirmations }) => {
           console.debug(
             `Submitting funding proof to deposit ${this.address} for ` +
               `Bitcoin transaction ${transaction.transactionID}...`
@@ -1016,8 +1044,8 @@ export default class Deposit {
             {},
             true
           )
-        }
-      )
+        })
+        .catch(this.notifyError)
     }
 
     return this.autoSubmittingState