Check dependencies before to crash...

compose/parser.go

@@ -1,8 +1,11 @@
 package compose
 
 import (
+	"fmt"
+	"katenary/helm"
 	"log"
 	"os"
+	"strings"
 
 	"gopkg.in/yaml.v3"
 )
@@ -27,6 +30,48 @@ func NewParser(filename string) *Parser {
 
 	p := &Parser{Data: c}
 
+	services := make(map[string][]string)
+	// get the service list, to be sure that everything is ok
+
+	for name, s := range c.Services {
+		if portlabel, ok := s.Labels[helm.LABEL_PORT]; ok {
+			services := strings.Split(portlabel, ",")
+			for _, serviceport := range services {
+				portexists := false
+				for _, found := range s.Ports {
+					if found == serviceport {
+						portexists = true
+					}
+				}
+				if !portexists {
+					s.Ports = append(s.Ports, serviceport)
+				}
+			}
+		}
+		if len(s.Ports) > 0 {
+			services[name] = s.Ports
+		}
+	}
+
+	// check if dependencies are resolved
+	missing := []string{}
+	for name, s := range c.Services {
+		for _, dep := range s.DependsOn {
+			if _, ok := services[dep]; !ok {
+				missing = append(missing, fmt.Sprintf(
+					"The service \"%s\" hasn't got "+
+						"declared port for dependency from \"%s\" - please "+
+						"append a %s label or a \"ports\" section in the docker-compose file",
+					dep, name, helm.LABEL_PORT),
+				)
+			}
+		}
+	}
+
+	if len(missing) > 0 {
+		log.Fatal(strings.Join(missing, "\n"))
+	}
+
 	return p
 }
 

compose/types.go

@@ -3,14 +3,14 @@ package compose
 // Compose is a complete docker-compse representation.
 type Compose struct {
 	Version  string                 `yaml:"version"`
-	Services map[string]Service     `yaml:"services"`
+	Services map[string]*Service    `yaml:"services"`
 	Volumes  map[string]interface{} `yaml:"volumes"`
 }
 
 // NewCompose resturs a Compose object.
 func NewCompose() *Compose {
 	c := &Compose{}
-	c.Services = make(map[string]Service)
+	c.Services = make(map[string]*Service)
 	c.Volumes = make(map[string]interface{})
 	return c
 }

generator/main.go

@@ -46,31 +46,14 @@ echo "Done"
 `
 
 // Create a Deployment for a given compose.Service. It returns a list of objects: a Deployment and a possible Service (kubernetes represnetation as maps).
-func CreateReplicaObject(name string, s compose.Service) chan interface{} {
-
-	// fetch label to specific exposed port, and add them in "ports" section
-	if portlabel, ok := s.Labels[helm.LABEL_PORT]; ok {
-		services := strings.Split(portlabel, ",")
-		for _, serviceport := range services {
-			portexists := false
-			for _, found := range s.Ports {
-				if found == serviceport {
-					portexists = true
-				}
-			}
-			if !portexists {
-				s.Ports = append(s.Ports, serviceport)
-			}
-		}
-	}
-
+func CreateReplicaObject(name string, s *compose.Service) chan interface{} {
 	ret := make(chan interface{}, len(s.Ports)+len(s.Expose)+1)
 	go parseService(name, s, ret)
 	return ret
 }
 
 // This function will try to yied deployment and services based on a service from the compose file structure.
-func parseService(name string, s compose.Service, ret chan interface{}) {
+func parseService(name string, s *compose.Service, ret chan interface{}) {
 	Magenta(ICON_PACKAGE+" Generating deployment for ", name)
 
 	o := helm.NewDeployment(name)
@@ -317,7 +300,7 @@ func parseService(name string, s compose.Service, ret chan interface{}) {
 }
 
 // Create a service (k8s).
-func createService(name string, s compose.Service) []interface{} {
+func createService(name string, s *compose.Service) []interface{} {
 
 	ret := make([]interface{}, 0)
 	Magenta(ICON_SERVICE+" Generating service for ", name)
@@ -363,7 +346,7 @@ func createService(name string, s compose.Service) []interface{} {
 }
 
 // Create an ingress.
-func createIngress(name string, port int, s compose.Service) *helm.Ingress {
+func createIngress(name string, port int, s *compose.Service) *helm.Ingress {
 	ingress := helm.NewIngress(name)
 	Values[name]["ingress"] = map[string]interface{}{
 		"class":   "nginx",
@@ -433,7 +416,7 @@ func waitPort(name string) chan int {
 	return c
 }
 
-func buildSelector(name string, s compose.Service) map[string]string {
+func buildSelector(name string, s *compose.Service) map[string]string {
 	return map[string]string{
 		"katenary.io/component": name,
 		"katenary.io/release":   "{{ .Release.Name }}",