add AppReqNet mocks and a few initial tests

.github/workflows/mock_checker.yml

@@ -0,0 +1,35 @@
+name: Check generated code is up to date
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - "**"
+
+jobs:
+  generated_code:
+    name: generated_code
+    runs-on: ubuntu-22.04
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          submodules: recursive
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: "go.mod"
+
+      - name: Generate code
+        run: |
+          scripts/generate.sh
+
+      - name: Print diff
+        run: git --no-pager diff
+
+      - name: Fail if diff exists
+        run: git --no-pager diff --quiet

peers/app_request_network.go

@@ -1,6 +1,8 @@
 // Copyright (C) 2023, Ava Labs, Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
+//go:generate mockgen -source=$GOFILE -destination=./mocks/mock_app_request_network.go -package=mocks
+
 package peers
 
 import (

scripts/build.sh

@@ -2,11 +2,14 @@
 # Copyright (C) 2024, Ava Labs, Inc. All rights reserved.
 # See the file LICENSE for licensing terms.
 
+set -e errexit
+
 # Root directory
 root=$(
     cd "$(dirname "${BASH_SOURCE[0]}")"
     cd .. && pwd
 )
 
+"$root"/scripts/generate.sh
 "$root"/scripts/build_relayer.sh
 "$root"/scripts/build_signature_aggregator.sh

scripts/generate.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+# Copyright (C) 2024, Ava Labs, Inc. All rights reserved.
+# See the file LICENSE for licensing terms.
+
+set -e errexit
+
+source "$root"/scripts/versions.sh
+go install -v "go.uber.org/mock/mockgen@$(getDepVersion go.uber.org/mock)"
+PATH="$PATH:$(go env GOPATH)/bin" go generate ./...

signature-aggregator/aggregator/aggregator.go

@@ -343,6 +343,8 @@ func (s *SignatureAggregator) CreateSignedMessage(
 	return nil, errNotEnoughSignatures
 }
 
+// TODO: consider making this function private. its only reference seems to be
+// within this module.
 func (s *SignatureAggregator) GetSubnetID(blockchainID ids.ID) (ids.ID, error) {
 	s.subnetsMapLock.RLock()
 	subnetID, ok := s.subnetIDsByBlockchainID[blockchainID]
@@ -359,6 +361,8 @@ func (s *SignatureAggregator) GetSubnetID(blockchainID ids.ID) (ids.ID, error) {
 	return subnetID, nil
 }
 
+// TODO: consider making this function private. its only reference seems to be
+// within this module.
 func (s *SignatureAggregator) SetSubnetID(blockchainID ids.ID, subnetID ids.ID) {
 	s.subnetsMapLock.Lock()
 	s.subnetIDsByBlockchainID[blockchainID] = subnetID

signature-aggregator/aggregator/aggregator_test.go

@@ -0,0 +1,87 @@
+package aggregator
+
+import (
+	"testing"
+
+	"github.com/ava-labs/avalanchego/ids"
+	"github.com/ava-labs/avalanchego/message"
+	"github.com/ava-labs/avalanchego/utils/constants"
+	"github.com/ava-labs/avalanchego/utils/logging"
+	"github.com/ava-labs/avalanchego/vms/platformvm/warp"
+	"github.com/ava-labs/awm-relayer/peers"
+	"github.com/ava-labs/awm-relayer/peers/mocks"
+	"github.com/ava-labs/awm-relayer/signature-aggregator/metrics"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/mock/gomock"
+)
+
+var sigAggMetrics *metrics.SignatureAggregatorMetrics
+var messageCreator message.Creator
+
+func instantiateAggregator(t *testing.T) (
+	*SignatureAggregator,
+	*mocks.MockAppRequestNetwork,
+) {
+	mockNetwork := mocks.NewMockAppRequestNetwork(gomock.NewController(t))
+	if sigAggMetrics == nil {
+		sigAggMetrics = metrics.NewSignatureAggregatorMetrics(prometheus.DefaultRegisterer)
+	}
+	if messageCreator == nil {
+		var err error
+		messageCreator, err = message.NewCreator(
+			logging.NoLog{},
+			prometheus.DefaultRegisterer,
+			constants.DefaultNetworkCompressionType,
+			constants.DefaultNetworkMaximumInboundTimeout,
+		)
+		require.Equal(t, err, nil)
+	}
+	aggregator, err := NewSignatureAggregator(
+		mockNetwork,
+		logging.NoLog{},
+		1024,
+		sigAggMetrics,
+		messageCreator,
+	)
+	require.Equal(t, err, nil)
+	return aggregator, mockNetwork
+}
+
+func TestCreateSignedMessageFailsWithNoValidators(t *testing.T) {
+	aggregator, mockNetwork := instantiateAggregator(t)
+	msg, err := warp.NewUnsignedMessage(0, ids.Empty, []byte{})
+	require.Equal(t, err, nil)
+	mockNetwork.EXPECT().GetSubnetID(ids.Empty).Return(ids.Empty, nil)
+	mockNetwork.EXPECT().ConnectToCanonicalValidators(ids.Empty).Return(
+		&peers.ConnectedCanonicalValidators{
+			ConnectedWeight:      0,
+			TotalValidatorWeight: 0,
+			ValidatorSet:         []*warp.Validator{},
+		},
+		nil,
+	)
+	_, err = aggregator.CreateSignedMessage(msg, ids.Empty, 80)
+	require.ErrorContains(t, err, "no signatures")
+}
+
+func TestCreateSignedMessageFailsWithoutSufficientConnectedStake(t *testing.T) {
+	aggregator, mockNetwork := instantiateAggregator(t)
+	msg, err := warp.NewUnsignedMessage(0, ids.Empty, []byte{})
+	require.Equal(t, err, nil)
+	mockNetwork.EXPECT().GetSubnetID(ids.Empty).Return(ids.Empty, nil)
+	mockNetwork.EXPECT().ConnectToCanonicalValidators(ids.Empty).Return(
+		&peers.ConnectedCanonicalValidators{
+			ConnectedWeight:      0,
+			TotalValidatorWeight: 1,
+			ValidatorSet:         []*warp.Validator{},
+		},
+		nil,
+	)
+	_, err = aggregator.CreateSignedMessage(msg, ids.Empty, 80)
+	require.ErrorContains(
+		t,
+		err,
+		"failed to connect to a threshold of stake",
+	)
+}