fix(dockerCompose): add ServiceDeployResources.MergeFirstWin()

pkg/domain/dockerCompose/config.go

@@ -798,6 +798,27 @@ func (sdr *ServiceDeployResources) Equal(equalable Equalable) bool {
 	}
 }
 
+// MergeFirstWin adds only attributes of the passed serviceDeployResources if
+// they are not already exists.
+func (sdr *ServiceDeployResources) MergeFirstWin(serviceDeployResources *ServiceDeployResources) {
+	switch {
+	case sdr == nil && serviceDeployResources == nil:
+		fallthrough
+	case sdr != nil && serviceDeployResources == nil:
+		return
+
+	// WARN: It's not possible to change the memory pointer sdr *ServiceDeployResources
+	// to a new initialized serviceDeployResources without returning the
+	// serviceDeployResources it self.
+	case sdr == nil && serviceDeployResources != nil:
+		sdr = NewServiceDeployResources()
+		fallthrough
+	default:
+		sdr.mergeFirstWinLimits(serviceDeployResources.Limits)
+		sdr.mergeFirstWinReservations(serviceDeployResources.Reservations)
+	}
+}
+
 // MergeLastWin merges adds or overwrite the attributes of the passed
 // serviceDeployResources with the existing one.
 func (sdr *ServiceDeployResources) MergeLastWin(serviceDeployResources *ServiceDeployResources) {
@@ -819,6 +840,32 @@ func (sdr *ServiceDeployResources) MergeLastWin(serviceDeployResources *ServiceD
 	}
 }
 
+func (sdr *ServiceDeployResources) mergeFirstWinLimits(limits *ServiceDeployResourcesLimits) {
+	switch {
+	case sdr.Limits == nil && limits != nil:
+		sdr.Limits = limits
+	case sdr.Limits != nil && limits == nil:
+		fallthrough
+	case sdr.Limits == nil && limits == nil:
+		return
+	default:
+		sdr.Limits.MergeFirstWin(limits)
+	}
+}
+
+func (sdr *ServiceDeployResources) mergeFirstWinReservations(reservations *ServiceDeployResourcesLimits) {
+	switch {
+	case sdr.Reservations == nil && reservations != nil:
+		sdr.Reservations = reservations
+	case sdr.Reservations != nil && reservations == nil:
+		fallthrough
+	case sdr.Reservations == nil && reservations == nil:
+		return
+	default:
+		sdr.Reservations.MergeFirstWin(reservations)
+	}
+}
+
 func (sdr *ServiceDeployResources) mergeLastWinLimits(limits *ServiceDeployResourcesLimits) {
 	switch {
 	case sdr.Limits == nil && limits != nil:
@@ -991,7 +1038,8 @@ func (sn *ServiceNetwork) MergeFirstWin(serviceNetwork *ServiceNetwork) {
 	// 	fallthrough
 
 	case sn == nil && serviceNetwork != nil:
-		sn = serviceNetwork
+		sn = NewServiceNetwork()
+		fallthrough
 	default:
 		sn.mergeFirstWinAliases(serviceNetwork.Aliases)
 	}

pkg/domain/dockerCompose/config_test.go

@@ -1543,6 +1543,155 @@ func TestServiceDeployResources_MergeLastWin(t *testing.T) {
 	}
 }
 
+func TestServiceDeployResources_MergeFirstWin(t *testing.T) {
+	require := require.New(t)
+
+	testCases := []struct {
+		serviceDeploymentResourcesA        *dockerCompose.ServiceDeployResources
+		serviceDeploymentResourcesB        *dockerCompose.ServiceDeployResources
+		expectedServiceDeploymentResources *dockerCompose.ServiceDeployResources
+	}{
+		{
+			serviceDeploymentResourcesA:        nil,
+			serviceDeploymentResourcesB:        nil,
+			expectedServiceDeploymentResources: nil,
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Limits: nil,
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Limits: nil,
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "2",
+					Memory: "1000",
+				},
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Limits: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Reservations: nil,
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Reservations: nil,
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "2",
+					Memory: "1000",
+				},
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+		{
+			serviceDeploymentResourcesA: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "",
+					Memory: "",
+				},
+			},
+			serviceDeploymentResourcesB: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+			expectedServiceDeploymentResources: &dockerCompose.ServiceDeployResources{
+				Reservations: &dockerCompose.ServiceDeployResourcesLimits{
+					CPUs:   "1",
+					Memory: "500",
+				},
+			},
+		},
+	}
+
+	for i, testCase := range testCases {
+		testCase.serviceDeploymentResourcesA.MergeFirstWin(testCase.serviceDeploymentResourcesB)
+		require.True(testCase.expectedServiceDeploymentResources.Equal(testCase.serviceDeploymentResourcesA), "Failed test case %v", i)
+	}
+}
+
 func TestServiceDeployResourcesLimits_Equal(t *testing.T) {
 	require := require.New(t)