Support loading templates from network (HTTP)

pkg/template/consts.go

@@ -0,0 +1,10 @@
+package template
+
+const (
+ XPodlikeExtension = "x-podlike"
+ ArgsProperty = "args"
+ ServicesProperty = "services"
+
+ TypeInline = "inline"
+ TypeHttp = "http"
+)

pkg/template/defaults.go

@@ -21,7 +21,7 @@ pod:
 func getTagForPod() string {
  v := version.Parse()
 
- if v.Tag == version.DEFAULT_VERSION {
+ if v.Tag == version.DEFAULT_VERSION || v.Tag == "master" {
  return "latest"
  } else {
  return v.Tag

pkg/template/hook.go

@@ -31,7 +31,7 @@ func podTemplateHookFunc() mapstructure.DecodeHookFunc {
 
  item := reflect.ValueOf(data).Interface()
  if m, ok := item.(map[string]interface{}); ok {
- if inline, ok := m["inline"]; ok {
+ if inline, ok := m[TypeInline]; ok {
 
  if t == reflect.TypeOf(podTemplate{}) {
  return podTemplate{Template: inline.(string), Inline: true}, nil
@@ -41,6 +41,18 @@ func podTemplateHookFunc() mapstructure.DecodeHookFunc {
  {Template: inline.(string), Inline: true},
  }, nil
  }
+
+ } else if httpSource, ok := m[TypeHttp]; ok {
+
+ if t == reflect.TypeOf(podTemplate{}) {
+ return podTemplate{Template: httpSource.(string), Http: true}, nil
+
+ } else if t.Kind() == reflect.Slice && t.Elem() == reflect.TypeOf(podTemplate{}) {
+ return []podTemplate{
+ {Template: httpSource.(string), Http: true},
+ }, nil
+ }
+
  }
  }
 

pkg/template/session.go

@@ -17,17 +17,17 @@ func (ts *transformSession) prepareConfiguration() {
 }
 
 func (ts *transformSession) collectTopLevelConfigurations(configFile types.ConfigFile) {
- if configSection, ok := configFile.Config["x-podlike"]; ok {
+ if configSection, ok := configFile.Config[XPodlikeExtension]; ok {
  globalConfig, ok := configSection.(map[string]interface{})
  if !ok {
  panic("top level x-podlike config is not a mapping")
  }
 
  // extract the top level global arguments first
- if args, ok := globalConfig["args"]; ok {
+ if args, ok := globalConfig[ArgsProperty]; ok {
  if mArgs, ok := args.(map[string]interface{}); ok {
  mergeRecursively(ts.Args, mArgs)
- delete(globalConfig, "args")
+ delete(globalConfig, ArgsProperty)
  } else {
  panic("template args is not a mapping")
  }
@@ -56,7 +56,7 @@ func (ts *transformSession) collectTopLevelConfigurations(configFile types.Confi
 }
 
 func (ts *transformSession) collectServiceLevelConfigurations(configFile types.ConfigFile) {
- services, ok := configFile.Config["services"]
+ services, ok := configFile.Config[ServicesProperty]
  if !ok {
  return // ok, some YAMLs might only define volumes and such
  }
@@ -72,14 +72,14 @@ func (ts *transformSession) collectServiceLevelConfigurations(configFile types.C
  panic(fmt.Sprintf("service definition is not a mapping for %s", serviceName))
  }
 
- configSection, ok := mDefinition["x-podlike"]
+ configSection, ok := mDefinition[XPodlikeExtension]
  if !ok {
  continue
  }
 
  if v := schema.Version(configFile.Config); versions.LessThan(v, "3.7") {
  // we have to delete the extension key below schema version 3.7
- delete(mDefinition, "x-podlike")
+ delete(mDefinition, XPodlikeExtension)
  }
 
  var config transformConfiguration

pkg/template/template.go

@@ -3,6 +3,8 @@ package template
 import (
  "bytes"
  "gopkg.in/yaml.v2"
+ "io/ioutil"
+ "net/http"
  "path"
  "text/template"
 )
@@ -38,8 +40,8 @@ func (t *podTemplate) render(tc *transformConfiguration) map[string]interface{}
 }
 
 func (t *podTemplate) prepareTemplate(workingDir string) *template.Template {
- name := "inline"
- if !t.Inline {
+ name := TypeInline
+ if !t.Inline && !t.Http {
  name = path.Base(t.Template)
  }
 
@@ -52,11 +54,23 @@ func (t *podTemplate) prepareTemplate(workingDir string) *template.Template {
 
  var err error
 
- if t.Inline {
+ if t.Http {
+ if resp, err := http.Get(t.Template); err == nil && resp.StatusCode == 200 {
+ defer resp.Body.Close()
+
+ if content, err := ioutil.ReadAll(resp.Body); err == nil {
+ tmpl, err = tmpl.Parse(string(content))
+ }
+ }
+
+ } else if t.Inline {
  tmpl, err = tmpl.Parse(t.Template)
+
  } else {
  tmpl, err = tmpl.ParseFiles(path.Join(workingDir, t.Template))
+
  }
+
  if err != nil {
  panic(err)
  }

pkg/template/template_test.go

@@ -0,0 +1,128 @@
+package template
+
+import (
+ "github.com/docker/cli/cli/compose/types"
+ "io/ioutil"
+ "net/http"
+ "net/http/httptest"
+ "os"
+ "testing"
+)
+
+func TestRender_File(t *testing.T) {
+ tmplFile, err := ioutil.TempFile("", "template")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer os.Remove(tmplFile.Name())
+
+ if _, err := tmplFile.WriteString(`
+component:
+ image: sample/{{ .Service.Labels.CompName }}:{{ .Args.TargetTag }}
+`); err != nil {
+ t.Fatal(err)
+ }
+ if err := tmplFile.Close(); err != nil {
+ t.Fatal(err)
+ }
+
+ tmpl := podTemplate{
+ Template: tmplFile.Name(),
+ }
+
+ rendered := tmpl.render(&transformConfiguration{
+ Service: &types.ServiceConfig{
+ Labels: types.Labels{
+ "CompName": "testing",
+ },
+ },
+ Args: map[string]interface{}{
+ "TargetTag": "0.1.2",
+ },
+ Session: &transformSession{},
+ })
+
+ if comp, ok := rendered["component"]; !ok {
+ t.Error("Root key not found")
+ } else if mComp, ok := comp.(map[string]interface{}); !ok {
+ t.Error("Invalid root key")
+ } else if image, ok := mComp["image"]; !ok {
+ t.Error("Image key not found")
+ } else if image != "sample/testing:0.1.2" {
+ t.Error("Invalid image value found")
+ }
+}
+
+func TestRender_Inline(t *testing.T) {
+ tmpl := podTemplate{
+ Template: `
+component:
+ image: sample/{{ .Service.Labels.CompName }}:{{ .Args.TargetTag }}
+`,
+ Inline: true,
+ }
+
+ rendered := tmpl.render(&transformConfiguration{
+ Service: &types.ServiceConfig{
+ Labels: types.Labels{
+ "CompName": "testing",
+ },
+ },
+ Args: map[string]interface{}{
+ "TargetTag": "0.1.2",
+ },
+ Session: &transformSession{},
+ })
+
+ if comp, ok := rendered["component"]; !ok {
+ t.Error("Root key not found")
+ } else if mComp, ok := comp.(map[string]interface{}); !ok {
+ t.Error("Invalid root key")
+ } else if image, ok := mComp["image"]; !ok {
+ t.Error("Image key not found")
+ } else if image != "sample/testing:0.1.2" {
+ t.Error("Invalid image value found")
+ }
+}
+
+func TestRender_Http(t *testing.T) {
+ server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ if r.RequestURI != "/template/testing" {
+ t.Fatal("Invalid template request")
+ }
+
+ w.WriteHeader(200)
+ w.Write([]byte(`
+component:
+ image: sample/{{ .Service.Labels.CompName }}:{{ .Args.TargetTag }}
+`))
+ }))
+ defer server.Close()
+
+ tmpl := podTemplate{
+ Template: server.URL + "/template/testing",
+ Http: true,
+ }
+
+ rendered := tmpl.render(&transformConfiguration{
+ Service: &types.ServiceConfig{
+ Labels: types.Labels{
+ "CompName": "testing",
+ },
+ },
+ Args: map[string]interface{}{
+ "TargetTag": "0.1.2",
+ },
+ Session: &transformSession{},
+ })
+
+ if comp, ok := rendered["component"]; !ok {
+ t.Error("Root key not found")
+ } else if mComp, ok := comp.(map[string]interface{}); !ok {
+ t.Error("Invalid root key")
+ } else if image, ok := mComp["image"]; !ok {
+ t.Error("Image key not found")
+ } else if image != "sample/testing:0.1.2" {
+ t.Error("Invalid image value found")
+ }
+}

pkg/template/types.go

@@ -27,6 +27,7 @@ type transformConfiguration struct {
 type podTemplate struct {
  Template string
  Inline bool
+ Http bool
 }
 
 type templateVars struct {