Use compose-go + improvements (#9)

Use compose-go https://github.com/compose-spec/compose-go  to make Katenary parsing compose file the official way.
Add labels:
- `volume-from` (with `same-pod`) to avoid volume repetition
- `ignore` to ignore a service
- `mapenv` (replaces the `env-to-service`) to map environment to helm variable (as a template string)
- `secret-vars` declares variables as secret values

More:
- Now, environment (as secret vars) are set in values.yaml
- Ingress has got annotations in values.yaml
- Probes (liveness probe) are improved
- fixed code to optimize
- many others fixes about path, bad volume check, refactorisation, tests...

helm/labels.go

@@ -0,0 +1,61 @@
+package helm
+
+import (
+	"bytes"
+	"html/template"
+)
+
+const ReleaseNameTpl = "{{ .Release.Name }}"
+const (
+	LABEL_MAP_ENV     = K + "/mapenv"
+	LABEL_ENV_SECRET  = K + "/secret-envfiles"
+	LABEL_PORT        = K + "/ports"
+	LABEL_INGRESS     = K + "/ingress"
+	LABEL_VOL_CM      = K + "/configmap-volumes"
+	LABEL_HEALTHCHECK = K + "/healthcheck"
+	LABEL_SAMEPOD     = K + "/same-pod"
+	LABEL_VOLUMEFROM  = K + "/volume-from"
+	LABEL_EMPTYDIRS   = K + "/empty-dirs"
+	LABEL_IGNORE      = K + "/ignore"
+	LABEL_SECRETVARS  = K + "/secret-vars"
+
+	//deprecated: use LABEL_MAP_ENV instead
+	LABEL_ENV_SERVICE = K + "/env-to-service"
+)
+
+// GetLabelsDocumentation returns the documentation for the labels.
+func GetLabelsDocumentation() string {
+	t, _ := template.New("labels").Parse(`
+# Labels
+{{.LABEL_IGNORE      | printf "%-33s"}}: ignore the container, it will not yied any object in the helm chart
+{{.LABEL_SECRETVARS  | printf "%-33s"}}: secret variables to push on a secret file
+{{.LABEL_ENV_SECRET  | printf "%-33s"}}: set the given file names as a secret instead of configmap
+{{.LABEL_MAP_ENV     | printf "%-33s"}}: map environment variable to a template string (yaml style)
+{{.LABEL_PORT        | printf "%-33s"}}: set the ports to expose as a service (coma separated)
+{{.LABEL_INGRESS     | printf "%-33s"}}: set the port to expose in an ingress (coma separated)
+{{.LABEL_VOL_CM      | printf "%-33s"}}: specifies that the volumes points on a configmap (coma separated)
+{{.LABEL_SAMEPOD     | printf "%-33s"}}: specifies that the pod should be deployed in the same pod than the given service name
+{{.LABEL_VOLUMEFROM  | printf "%-33s"}}: specifies that the volumes to be mounted from the given service (yaml style)
+{{.LABEL_EMPTYDIRS   | printf "%-33s"}}: specifies that the given volume names should be "emptyDir" instead of persistentVolumeClaim (coma separated)
+{{.LABEL_HEALTHCHECK | printf "%-33s"}}: specifies that the container should be monitored by a healthcheck, **it overrides the docker-compose healthcheck**. 
+{{ printf "%-34s" ""}} You can use these form of label values:
+{{ printf "%-35s" ""}}- "http://[not used address][:port][/path]" to specify an http healthcheck
+{{ printf "%-35s" ""}}- "tcp://[not used address]:port" to specify a tcp healthcheck
+{{ printf "%-35s" ""}}- other string is condidered as a "command" healthcheck
+    `)
+	buff := bytes.NewBuffer(nil)
+	t.Execute(buff, map[string]string{
+		"LABEL_ENV_SECRET":  LABEL_ENV_SECRET,
+		"LABEL_PORT":        LABEL_PORT,
+		"LABEL_INGRESS":     LABEL_INGRESS,
+		"LABEL_VOL_CM":      LABEL_VOL_CM,
+		"LABEL_HEALTHCHECK": LABEL_HEALTHCHECK,
+		"LABEL_SAMEPOD":     LABEL_SAMEPOD,
+		"LABEL_VOLUMEFROM":  LABEL_VOLUMEFROM,
+		"LABEL_EMPTYDIRS":   LABEL_EMPTYDIRS,
+		"LABEL_IGNORE":      LABEL_IGNORE,
+		"LABEL_MAP_ENV":     LABEL_MAP_ENV,
+		"LABEL_SECRETVARS":  LABEL_SECRETVARS,
+	})
+	return buff.String()
+}