Support alternative depends_on configuration

pkg/template/depends_on.go

@@ -0,0 +1,84 @@
+package template
+
+import (
+ "fmt"
+ "github.com/docker/cli/cli/compose/loader"
+)
+
+// Remove and return the Compose v2 compatible depends_on configurations.
+// These won't parse for the v3 service type, so we'll just have to add them
+// back after the conversion is done.
+func extractDependsOnConfig(configuration map[string]interface{}) map[string]interface{} {
+ servicesWithDependsOn := map[string]interface{}{}
+
+ for name, config := range configuration {
+ if mConfig, ok := config.(map[string]interface{}); !ok {
+ panic(fmt.Sprintf("unexpected service definition type: %T", config))
+
+ } else if dependsOn, ok := mConfig["depends_on"]; ok {
+ validateDependsOn(dependsOn)
+
+ servicesWithDependsOn[name] = map[string]interface{}{
+ "depends_on": dependsOn,
+ }
+
+ delete(mConfig, "depends_on")
+ }
+ }
+
+ return servicesWithDependsOn
+}
+
+func validateDependsOn(v interface{}) {
+ switch v.(type) {
+ case []string:
+ // ok
+
+ case []interface{}:
+ for _, item := range v.([]interface{}) {
+ if _, ok := item.(string); !ok {
+ panic(fmt.Sprintf("invalid depends_on list item: %+v %T", item, item))
+ }
+ }
+
+ case map[string]interface{}:
+ for svc, config := range v.(map[string]interface{}) {
+ if mConfig, ok := config.(map[string]interface{}); !ok {
+ panic(fmt.Sprintf("invalid depends_on defined for %s (type %T)", svc, config))
+ } else if condition, ok := mConfig["condition"]; !ok {
+ panic(fmt.Sprintf("condition not found for %s dependency", svc))
+ } else if condition != "service_started" && condition != "service_healthy" {
+ panic(fmt.Sprintf("invalid condition defined for %s : %s", svc, condition))
+ }
+ }
+
+ default:
+ panic(fmt.Sprintf("unexpected depends_on config type: %T", v))
+ }
+}
+
+// Merge in the previously removed depends_on configurations to the rendered YAML string.
+func insertDependsOnConfig(target string, source map[string]interface{}, service string) string {
+ var config interface{}
+
+ if svcConfig, ok := source[service]; !ok {
+ return target
+ } else if mConfig, ok := svcConfig.(map[string]interface{}); !ok {
+ panic(fmt.Sprintf("somehow lost the depends_on settings for %s", service))
+ } else {
+ config = mConfig["depends_on"]
+ }
+
+ if config == nil {
+ panic(fmt.Sprintf("somehow lost the depends_on settings for %s", service))
+ }
+
+ parsed, err := loader.ParseYAML([]byte(target))
+ if err != nil {
+ panic(fmt.Sprintf("failed to parse the output YAML for %s", service))
+ }
+
+ parsed["depends_on"] = config
+
+ return convertToYaml(parsed)
+}

pkg/template/testdata/stack-with-dependencies.yml

@@ -0,0 +1,25 @@
+version: '3.5'
+services:
+
+ dep:
+ image: sample/inline
+ x-podlike:
+ templates:
+
+ - inline:
+ first:
+ image: sample/first
+
+ - inline:
+ second:
+ image: sample/second
+ depends_on:
+ first:
+ condition: service_healthy
+
+ - inline:
+ third:
+ image: sample/third
+ depends_on:
+ - first
+ - second

pkg/template/transform.go

@@ -109,12 +109,19 @@ func executeTransformers(tc *transformConfiguration) (string, string) {
 
  mergeServiceProperties(definition, tc.getServiceConfig(), mergedTransformerKeys)
 
+ // we need to remove depends_on here, the Compose v2 compatible format won't parse for the v3 service type
+ servicesWithDependsOn := extractDependsOnConfig(definition)
+
  converted := convertToServices(definition, tc.Session.WorkingDir)
  if len(converted) != 1 {
  panic(fmt.Sprintf("somehow we ended up with %d definitions for the main component", len(converted)))
  }
 
  comp := convertToYaml(converted[0])
+
+ // add back the removed depends_on
+ comp = insertDependsOnConfig(comp, servicesWithDependsOn, converted[0].Name)
+
  return converted[0].Name, comp
 }
 
@@ -132,8 +139,16 @@ func executeTemplates(tc *transformConfiguration) map[string]string {
  mergeRecursively(definition, tmpl.render(tc))
  }
 
+ // we need to remove depends_on here, the Compose v2 compatible format won't parse for the v3 service type
+ servicesWithDependsOn := extractDependsOnConfig(definition)
+
  for _, comp := range convertToServices(definition, tc.Session.WorkingDir) {
- components[comp.Name] = convertToYaml(comp)
+ rendered := convertToYaml(comp)
+
+ // add back the removed depends_on
+ rendered = insertDependsOnConfig(rendered, servicesWithDependsOn, comp.Name)
+
+ components[comp.Name] = rendered
  }
 
  return components

pkg/template/transform_test.go

@@ -230,6 +230,39 @@ func TestTransform_Copy(t *testing.T) {
  })
 }
 
+func TestTransform_WithDependencies(t *testing.T) {
+ output := Transform("testdata/stack-with-dependencies.yml")
+ verifyTemplatedComponent(t, output, "dep", "first",
+ func(c *component.Component, s *types.ServiceConfig) bool {
+ return c.Image == "sample/first"
+ })
+ verifyTemplatedComponent(t, output, "dep", "second",
+ func(c *component.Component, s *types.ServiceConfig) bool {
+ return c.Image == "sample/second"
+ },
+ func(c *component.Component, s *types.ServiceConfig) bool {
+ if deps, err := c.GetDependencies(); err != nil {
+ return false
+ } else {
+ return len(deps) == 1 &&
+ deps[0].Name == "first" && deps[0].NeedsHealthyState == true
+ }
+ })
+ verifyTemplatedComponent(t, output, "dep", "third",
+ func(c *component.Component, s *types.ServiceConfig) bool {
+ return c.Image == "sample/third"
+ },
+ func(c *component.Component, s *types.ServiceConfig) bool {
+ if deps, err := c.GetDependencies(); err != nil {
+ return false
+ } else {
+ return len(deps) == 2 &&
+ deps[0].Name == "first" && deps[0].NeedsHealthyState == false &&
+ deps[1].Name == "second" && deps[1].NeedsHealthyState == false
+ }
+ })
+}
+
 func TestTransform_CustomController(t *testing.T) {
  nonDefaultImage = true
  defer func() {