Circular dependency check

fixtures-code/process-compose-circular.yaml

@@ -8,18 +8,13 @@ processes:
 
   process2:
     command: "echo process2"
-    availability:
-      restart: "on_failure"
     depends_on:
-      process3:
+      process1:
         condition: process_completed_successfully
 
   process3:
     command: "echo process3"
-    availability:
-      restart: "on_failure"
-      backoff_seconds: 2
-#    depends_on:
-#      process1:
-#        condition: process_completed_successfully
+    depends_on:
+      process1:
+        condition: process_completed_successfully
 

fixtures-code/process-compose-non-circular.yaml

@@ -0,0 +1,11 @@
+version: "0.5"
+processes:
+  process1:
+    command: "echo process1"
+
+  process3:
+    command: "echo process3"
+    depends_on:
+      process1:
+        condition: process_completed_successfully
+

src/app/system_test.go

@@ -130,28 +130,27 @@ func TestSystem_TestComposeChainExit(t *testing.T) {
 	})
 }
 
-//func TestSystem_TestComposeCircular(t *testing.T) {
-//	fixture := filepath.Join("..", "..", "fixtures", "process-compose-circular.yaml")
-//	t.Run(fixture, func(t *testing.T) {
-//		project, err := loader.Load(&loader.LoaderOptions{
-//			FileNames: []string{fixture},
-//		})
-//		if err != nil {
-//			t.Errorf(err.Error())
-//			return
-//		}
-//		runner, err := NewProjectRunner(project, []string{}, false)
-//		if err != nil {
-//			t.Errorf(err.Error())
-//			return
-//		}
-//		exitCode := runner.Run()
-//		want := 42
-//		if want != exitCode {
-//			t.Errorf("Project.Run() = %v, want %v", exitCode, want)
-//		}
-//	})
-//}
+func TestSystem_TestComposeCircular(t *testing.T) {
+	fixture1 := filepath.Join("..", "..", "fixtures-code", "process-compose-circular.yaml")
+	fixture2 := filepath.Join("..", "..", "fixtures-code", "process-compose-non-circular.yaml")
+	t.Run(fixture1, func(t *testing.T) {
+		_, err := loader.Load(&loader.LoaderOptions{
+			FileNames: []string{fixture1},
+		})
+		if err == nil {
+			t.Errorf("should fail on cirlcular dependency")
+			return
+		}
+
+		_, err = loader.Load(&loader.LoaderOptions{
+			FileNames: []string{fixture2},
+		})
+		if err != nil {
+			t.Errorf(err.Error())
+			return
+		}
+	})
+}
 
 func TestSystem_TestComposeScale(t *testing.T) {
 	fixture := filepath.Join("..", "..", "fixtures-code", "process-compose-scale.yaml")

src/loader/loader.go

@@ -27,7 +27,7 @@ func Load(opts *LoaderOptions) (*types.Project, error) {
 		opts.projects = append(opts.projects, p)
 	}
 	mergedProject, err := merge(opts)
-	mergedProject.ValidateAfterMerge()
+	err = mergedProject.ValidateAfterMerge()
 	return mergedProject, err
 
 }

src/types/validators.go

@@ -1,6 +1,7 @@
 package types
 
 import (
+	"fmt"
 	"github.com/f1bonacc1/process-compose/src/command"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
@@ -14,9 +15,10 @@ func (p *Project) Validate() {
 	p.validateProcessConfig()
 }
 
-func (p *Project) ValidateAfterMerge() {
+func (p *Project) ValidateAfterMerge() error {
 	p.assignDefaultProcessValues()
 	p.cloneReplicas()
+	return p.validateNoCircularDependencies()
 }
 
 func (p *Project) validateLogLevel() {
@@ -100,3 +102,41 @@ func (p *Project) cloneReplicas() {
 		p.Processes[proc.ReplicaName] = proc
 	}
 }
+
+func (p *Project) validateNoCircularDependencies() error {
+	visited := make(map[string]bool, len(p.Processes))
+	stack := make(map[string]bool)
+	for name := range p.Processes {
+		if !visited[name] {
+			if p.isCyclicHelper(name, visited, stack) {
+				return fmt.Errorf("circular dependency found in %s", name)
+			}
+		}
+	}
+	return nil
+}
+
+func (p *Project) isCyclicHelper(procName string, visited map[string]bool, stack map[string]bool) bool {
+	visited[procName] = true
+	stack[procName] = true
+
+	processes, err := p.getProcesses(procName)
+	if err != nil {
+		return false
+	}
+	for _, process := range processes {
+		dependencies := process.GetDependencies()
+		for _, neighbor := range dependencies {
+			if !visited[neighbor] {
+				if p.isCyclicHelper(neighbor, visited, stack) {
+					return true
+				}
+			} else if stack[neighbor] {
+				return true
+			}
+		}
+	}
+
+	stack[procName] = false
+	return false
+}