diff --git a/bindings/errors.go b/bindings/errors.go
new file mode 100644
index 0000000000000000000000000000000000000000..14b8ad7785a38a29a5a2323287a9fa85680e8402
--- /dev/null
+++ b/bindings/errors.go
@@ -0,0 +1,68 @@
+///////////////////////////////////////////////////////////////////////////////
+// Copyright © 2020 xx network SEZC //
+// //
+// Use of this source code is governed by a license that can be found in the //
+// LICENSE file //
+///////////////////////////////////////////////////////////////////////////////
+
+package bindings
+
+import (
+ "context"
+ "strings"
+)
+
+// ErrToUserErr maps backend patterns to user friendly error messages.
+// Example format:
+// (Back-end) "Building new HostPool because no HostList stored:": (Front-end) "Missing host list",
+var ErrToUserErr = map[string]string{
+ // todo populate with common errors
+}
+
+// Error codes
+const UnrecognizedCode = "UR: "
+const UnrecognizedMessage = UnrecognizedCode + "Unrecognized error from XX backend, please report"
+
+// ErrorStringToUserFriendlyMessage takes a passed in errStr which will be
+// a backend generated error. These may be error specifically written by
+// the backend team or lower level errors gotten from low level dependencies.
+// This function will parse the error string for common errors provided from
+// ErrToUserErr to provide a more user-friendly error message for the front end.
+// If the error is not common, some simple parsing is done on the error message
+// to make it more user-accessible, removing backend specific jargon.
+func ErrorStringToUserFriendlyMessage(errStr string) string {
+ // Go through common errors
+ for backendErr, userFriendly := range ErrToUserErr {
+ // Determine if error contains a common error
+ // Fixme: later versions may be improved by using regex
+ if strings.HasPrefix(errStr, backendErr) {
+ return userFriendly
+ }
+ }
+
+ descStr := "desc = "
+ // If this contains an rpc error, determine how to handle it
+ if strings.Contains(errStr, context.DeadlineExceeded.Error()) {
+ // If there is a context deadline exceeded message, return the higher level
+ // as context deadline exceeded is not informative
+ rpcErr := "rpc "
+ rpcIdx := strings.Index(errStr, rpcErr)
+ return UnrecognizedCode + errStr[:rpcIdx]
+ } else if strings.Contains(errStr, descStr) {
+ // If containing an rpc error where context deadline exceeded
+ // is NOT involved, the error returned server-side is often
+ //more informative
+ descIdx := strings.Index(errStr, descStr)
+ // return everything after "desc = "
+ return UnrecognizedCode + errStr[descIdx+len(descStr):]
+ }
+
+ // If a compound error message, return the highest level message
+ errParts := strings.Split(errStr, ":")
+ if len(errParts) > 1 {
+ // Return everything before the first :
+ return UnrecognizedCode + errParts[0]
+ }
+
+ return UnrecognizedMessage
+}
diff --git a/bindings/errors_test.go b/bindings/errors_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..78115099fe32d1a8b40155350d306769fbe8fa51
--- /dev/null
+++ b/bindings/errors_test.go
@@ -0,0 +1,82 @@
+///////////////////////////////////////////////////////////////////////////////
+// Copyright © 2020 xx network SEZC //
+// //
+// Use of this source code is governed by a license that can be found in the //
+// LICENSE file //
+///////////////////////////////////////////////////////////////////////////////
+
+package bindings
+
+import (
+ "context"
+ "strings"
+ "testing"
+)
+
+// Unit test
+func TestErrorStringToUserFriendlyMessage(t *testing.T) {
+ // Setup: Populate map
+ backendErrs := []string{"Failed to Unmarshal Conversation", "failed to create group key preimage",
+ "Failed to unmarshal SentRequestMap"}
+ userErrs := []string{"Could not retrieve conversation", "Failed to initiate group chat",
+ "Failed to pull up friend requests"}
+
+ for i, exampleErr := range backendErrs {
+ ErrToUserErr[exampleErr] = userErrs[i]
+ }
+
+ // Check if a mapped common error returns the expected user friendly error
+ received := ErrorStringToUserFriendlyMessage(backendErrs[0])
+ if strings.Compare(received, userErrs[0]) != 0 {
+ t.Errorf("Unexpected user friendly message returned from common error mapping."+
+ "\n\tExpected: %s"+
+ "\n\tReceived: %v", userErrs[0], received)
+ }
+
+ // Test RPC error in which high level information should
+ // be passed along (ie context deadline exceeded error)
+ expected := "Could not poll network: "
+ rpcPrefix := "rpc error: desc = "
+ rpcErr := expected + rpcPrefix + context.DeadlineExceeded.Error()
+ received = ErrorStringToUserFriendlyMessage(rpcErr)
+ if strings.Compare(UnrecognizedCode+expected, received) != 0 {
+ t.Errorf("Rpc error parsed unxecpectedly with error "+
+ "\n\"%s\" "+
+ "\n\tExpected: %s"+
+ "\n\tReceived: %v", rpcErr, UnrecognizedCode+expected, received)
+ }
+
+ // Test RPC error where server side error information is provided
+ serverSideError := "Could not parse message! Please try again with a properly crafted message"
+ rpcErr = rpcPrefix + serverSideError
+ received = ErrorStringToUserFriendlyMessage(rpcErr)
+ if strings.Compare(UnrecognizedCode+serverSideError, received) != 0 {
+ t.Errorf("RPC error parsed unexpectedly with error "+
+ "\n\"%s\" "+
+ "\n\tExpected: %s"+
+ "\n\tReceived: %v", rpcErr, UnrecognizedCode+serverSideError, received)
+ }
+
+ // Test uncommon error, should return highest level message
+ expected = "failed to register with permissioning"
+ uncommonErr := expected + ": sendRegistrationMessage: Unable to contact Identity Server"
+ received = ErrorStringToUserFriendlyMessage(uncommonErr)
+ if strings.Compare(received, UnrecognizedCode+expected) != 0 {
+ t.Errorf("Uncommon error parsed unexpectedly with error "+
+ "\n\"%s\" "+
+ "\n\tExpected: %s"+
+ "\n\tReceived: %s", uncommonErr, UnrecognizedCode+expected, received)
+ }
+
+ // Test fully unrecognizable and un-parsable message,
+ // should hardcoded error message
+ uncommonErr = "failed to register with permissioning"
+ received = ErrorStringToUserFriendlyMessage(uncommonErr)
+ if strings.Compare(UnrecognizedMessage, received) != 0 {
+ t.Errorf("Uncommon error parsed unexpectedly with error "+
+ "\n\"%s\" "+
+ "\n\tExpected: %s"+
+ "\n\tReceived: %s", uncommonErr, UnrecognizedMessage, received)
+ }
+
+}