Add json schema generation

go.mod

@@ -2,8 +2,10 @@ module git.scc.kit.edu/feudal/feudalClient
 
 require (
 	git.scc.kit.edu/feudal/feudalScripts/v2 v2.0.0
+	github.com/alecthomas/jsonschema v0.0.0-20190122210438-a6952de1bbe6
 	github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc // indirect
 	github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/streadway/amqp v0.0.0-20181205114330-a314942b2fd9
 	github.com/stretchr/testify v1.3.0 // indirect
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6

go.sum

 git.scc.kit.edu/feudal/feudalScripts/v2 v2.0.0 h1:3907HJ9XEZSuEZ0oAuijssG9SGFjAdmyDt8P7SlFFZY=
 git.scc.kit.edu/feudal/feudalScripts/v2 v2.0.0/go.mod h1:EVXrOHOlnw3VZ02LZQDSN7bxldpJ7p31tfKZ5zqAEXA=
+github.com/alecthomas/jsonschema v0.0.0-20190122210438-a6952de1bbe6 h1:xadBCbc8D9mmkaNfCsEBHbIoCjbayJXJNsY1JjPjNio=
+github.com/alecthomas/jsonschema v0.0.0-20190122210438-a6952de1bbe6/go.mod h1:qpebaTNSsyUn5rPSJMsfqEtDw71TTggXM6stUDI16HA=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc h1:cAKDfWh5VpdgMhJosfJnn5/FoN2SRZ4p7fJNX58YPaU=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf h1:qet1QNfXsQxTZqLG4oE62mJzwPIB8+Tee4RNCL9ulrY=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/streadway/amqp v0.0.0-20181205114330-a314942b2fd9 h1:37QTz/gdHBLQcsmgMTnQDSWCtKzJ7YnfI2M2yTdr4BQ=

main.go

 package main
 
 import (
+	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
 
 	"git.scc.kit.edu/feudal/feudalClient/config"
-	"git.scc.kit.edu/feudal/feudalClient/deployments"
+	deps "git.scc.kit.edu/feudal/feudalClient/deployments"
 	"git.scc.kit.edu/feudal/feudalClient/sink"
 	"git.scc.kit.edu/feudal/feudalClient/sink/script"
 	"git.scc.kit.edu/feudal/feudalClient/source"
 	"git.scc.kit.edu/feudal/feudalClient/source/amqp"
 	"git.scc.kit.edu/feudal/feudalClient/source/rest"
-	"gopkg.in/alecthomas/kingpin.v2"
+	scripts "git.scc.kit.edu/feudal/feudalScripts/v2"
+	"github.com/alecthomas/jsonschema"
+	kingpin "gopkg.in/alecthomas/kingpin.v2"
 )
 
 var (
@@ -23,12 +27,14 @@ var (
 	).Author(
 		"Lukas Burgey",
 	).Version(
-		"v2.0.1",
+		"v2.1.0",
 	)
-	cmdStart      = app.Command("start", "Starts the client in its normal operation mode.").Default()
-	cmdDeregister = app.Command("deregister", "Before disabling the client: Use deregister to inform the backend that the client ceases operation.")
+	cmdStart       = app.Command("start", "Starts the client in its normal operation mode.").Default()
+	cmdDeregister  = app.Command("deregister", "Before disabling the client: Use deregister to inform the backend that the client ceases operation.")
+	cmdSchema      = app.Command("schema", "Can be used to generate JSON schemas (Draft 4, see json-schema.org) for the validation of script inputs and outputs.")
+	schemaSelector = cmdSchema.Arg("selector", "Select the schema to generate.").Required().Enum("input", "output", "config")
 
-	configFile          = app.Flag("config", "Config file to file to use.").Short('c').Required().String()
+	configFile          = app.Flag("config", "Config file to use.").Short('c').String()
 	scriptDebugging     = app.Flag("debug-scripts", "Display debugging info concerning executed scripts").Bool()
 	backendDebugging    = app.Flag("debug-backend", "Display debugging info concerning the backend").Bool()
 	debugAll            = app.Flag("debug", "Display all debugging info").Bool()
@@ -106,13 +112,39 @@ func start(conf *config.Config) {
 	}
 }
 
+func printSchema(i interface{}) {
+	schema := jsonschema.Reflect(i)
+	bs, err := json.MarshalIndent(schema, "", "  ")
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("%s", bs)
+}
+
 func main() {
 	var err error
 
 	// get arguments
 	cmd := kingpin.MustParse(app.Parse(os.Args[1:]))
 
+	// Do things that need no config or debugging
+	switch cmd {
+	case "schema":
+		switch *schemaSelector {
+		case "input":
+			printSchema(scripts.Input{})
+		case "output":
+			printSchema(scripts.Output{})
+		case "config":
+			printSchema(config.Config{})
+		}
+		return
+	}
+
 	// read the config file
+	if *configFile == "" {
+		log.Fatalf("No config file. Unable to proceed. Provide the --config flag")
+	}
 	conf, err := config.ReadConfig(*configFile)
 	if err != nil {
 		log.Fatalf("[Conf] %s", err)