Add time trigger cron spec examination tool (#680)

builder/builder.go

@@ -72,7 +72,7 @@ func MakeBuilder(sharedVolumePath string) *Builder {
 
 func (builder *Builder) VersionHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json; charset=utf-8")
-	fmt.Fprintf(w, fission.VersionInfo().String())
+	fmt.Fprintf(w, fission.BuildInfo().String())
 }
 
 func (builder *Builder) Handler(w http.ResponseWriter, r *http.Request) {

controller/api.go

@@ -155,7 +155,7 @@ func (api *API) getLogDBConfig(dbType string) logDBConfig {
 
 func (api *API) HomeHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json; charset=utf-8")
-	fmt.Fprintf(w, fission.VersionInfo().String())
+	fmt.Fprintf(w, fission.ApiInfo().String())
 }
 
 func (api *API) ApiVersionMismatchHandler(w http.ResponseWriter, r *http.Request) {

controller/client/client.go

@@ -18,7 +18,9 @@ package client
 
 import (
 	"bytes"
+	"encoding/json"
 	"errors"
+	"fmt"
 	"io/ioutil"
 	"net/http"
 	"strings"
@@ -88,3 +90,25 @@ func (c *Client) handleCreateResponse(resp *http.Response) ([]byte, error) {
 	body, err := ioutil.ReadAll(resp.Body)
 	return body, err
 }
+
+func (c *Client) ServerInfo() (*fission.ServerInfo, error) {
+	url := fmt.Sprintf(c.Url)
+	resp, err := http.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	info := &fission.ServerInfo{}
+	err = json.Unmarshal(body, info)
+	if err != nil {
+		return nil, err
+	}
+
+	return info, nil
+}

environments/fetcher/fetcher.go

@@ -165,7 +165,7 @@ func writeSecretOrConfigMap(dataMap map[string][]byte, dirPath string) error {
 
 func (fetcher *Fetcher) VersionHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json; charset=utf-8")
-	fmt.Fprintf(w, fission.VersionInfo().String())
+	fmt.Fprintf(w, fission.BuildInfo().String())
 }
 
 func (fetcher *Fetcher) FetchHandler(w http.ResponseWriter, r *http.Request) {

fission-bundle/main.go

@@ -140,7 +140,7 @@ Options:
   --builderMgr                    Start builder manager.
   --version                       Print version information
 `
-	version := fmt.Sprintf("Fission Bundle Version: %v", fission.VersionInfo().String())
+	version := fmt.Sprintf("Fission Bundle Version: %v", fission.BuildInfo().String())
 	arguments, err := docopt.Parse(usage, nil, true, version, false)
 	if err != nil {
 		log.Fatalf("Error: %v", err)

fission/main.go

@@ -18,13 +18,10 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
-	"net/http"
 	"os"
 	"path/filepath"
-	"strings"
 
-	version "github.com/fission/fission"
+	"github.com/fission/fission"
 	"github.com/urfave/cli"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
@@ -47,20 +44,6 @@ func getKubeConfigPath() string {
 	return kubeConfig
 }
 
-func getFissionAPIVersion(apiUrl string) (string, error) {
-	resp, err := http.Get(apiUrl)
-	if err != nil {
-		return "", err
-	}
-	defer resp.Body.Close()
-
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return "", err
-	}
-	return strings.TrimRight(string(body), "\n"), nil
-}
-
 func getServerUrl() string {
 	var serverUrl string
 	// Use FISSION_URL env variable if set; otherwise, port-forward to controller.
@@ -87,16 +70,17 @@ func main() {
 	app := cli.NewApp()
 	app.Name = "fission"
 	app.Usage = "Serverless functions for Kubernetes"
-	app.Version = version.Version
+	app.Version = fission.Version
 
 	cli.VersionPrinter = func(c *cli.Context) {
-		clientVer := version.VersionInfo().String()
+		clientVer := fission.BuildInfo().String()
 		fmt.Printf("Client Version: %v\n", clientVer)
-		serverVer, err := getFissionAPIVersion(getServerUrl())
+		serverInfo, err := getClient(getServerUrl()).ServerInfo()
 		if err != nil {
 			fmt.Printf("Error getting Fission API version: %v", err)
 		} else {
-			fmt.Printf("Server Version: %v", serverVer)
+			serverVer := serverInfo.Build.String()
+			fmt.Printf("Server Version: %v\n", serverVer)
 		}
 	}
 
@@ -177,14 +161,16 @@ func main() {
 
 	// timetriggers
 	ttNameFlag := cli.StringFlag{Name: "name", Usage: "Time Trigger name"}
-	ttCronFlag := cli.StringFlag{Name: "cron", Usage: "Time Trigger cron spec ('0 30 * * *', '@every 5m', '@hourly')"}
+	ttCronFlag := cli.StringFlag{Name: "cron", Usage: "Time trigger cron spec with each asterisk representing respectively second, minute, hour, the day of the month, month and day of the week. Also supports readable formats like '@every 5m', '@hourly'"}
 	ttFnNameFlag := cli.StringFlag{Name: "function", Usage: "Function name"}
+	ttRoundFlag := cli.IntFlag{Name: "round", Value: 1, Usage: "Get next N rounds of invocation time"}
 	ttSubcommands := []cli.Command{
-		{Name: "create", Aliases: []string{"add"}, Usage: "Create Time trigger", Flags: []cli.Flag{ttNameFlag, ttFnNameFlag, fnNamespaceFlag, ttCronFlag, specSaveFlag}, Action: ttCreate},
+		{Name: "create", Aliases: []string{"add"}, Usage: "Create time trigger", Flags: []cli.Flag{ttNameFlag, ttFnNameFlag, fnNamespaceFlag, ttCronFlag, specSaveFlag}, Action: ttCreate},
-		{Name: "get", Usage: "Get Time trigger", Flags: []cli.Flag{triggerNamespaceFlag}, Action: ttGet},
+		{Name: "get", Usage: "Get time trigger", Flags: []cli.Flag{triggerNamespaceFlag}, Action: ttGet},
-		{Name: "update", Usage: "Update Time trigger", Flags: []cli.Flag{ttNameFlag, triggerNamespaceFlag, ttCronFlag, ttFnNameFlag}, Action: ttUpdate},
+		{Name: "update", Usage: "Update time trigger", Flags: []cli.Flag{ttNameFlag, triggerNamespaceFlag, ttCronFlag, ttFnNameFlag}, Action: ttUpdate},
-		{Name: "delete", Usage: "Delete Time trigger", Flags: []cli.Flag{ttNameFlag, triggerNamespaceFlag}, Action: ttDelete},
+		{Name: "delete", Usage: "Delete time trigger", Flags: []cli.Flag{ttNameFlag, triggerNamespaceFlag}, Action: ttDelete},
-		{Name: "list", Usage: "List Time triggers", Flags: []cli.Flag{triggerNamespaceFlag}, Action: ttList},
+		{Name: "list", Usage: "List time triggers", Flags: []cli.Flag{triggerNamespaceFlag}, Action: ttList},
+		{Name: "showschedule", Aliases: []string{"show"}, Usage: "Show schedule for cron spec", Flags: []cli.Flag{ttCronFlag, ttRoundFlag}, Action: ttTest},
 	}
 
 	// Message queue trigger

fission/timetrigger.go

@@ -20,15 +20,42 @@ import (
 	"fmt"
 	"os"
 	"text/tabwriter"
+	"time"
 
+	"github.com/robfig/cron"
 	"github.com/satori/go.uuid"
 	"github.com/urfave/cli"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	"github.com/fission/fission"
+	"github.com/fission/fission/controller/client"
 	"github.com/fission/fission/crd"
 )
 
+func getAPITimeInfo(client *client.Client) time.Time {
+	serverInfo, err := client.ServerInfo()
+	if err != nil {
+		fatal(fmt.Sprintf("Error syncing server time information: %v", err))
+	}
+	return serverInfo.ServerTime.CurrentTime
+}
+
+func getCronNextNActivationTime(cronSpec string, serverTime time.Time, round int) error {
+	sched, err := cron.Parse(cronSpec)
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("Current Server Time: \t%v\n", serverTime.Format(time.RFC3339))
+
+	for i := 0; i < round; i++ {
+		serverTime = sched.Next(serverTime)
+		fmt.Printf("Next %v invocation: \t%v\n", i+1, serverTime.Format(time.RFC3339))
+	}
+
+	return nil
+}
+
 func ttCreate(c *cli.Context) error {
 	client := getClient(c.GlobalString("server"))
 
@@ -40,11 +67,12 @@ func ttCreate(c *cli.Context) error {
 	if len(fnName) == 0 {
 		fatal("Need a function name to create a trigger, use --function")
 	}
+
 	fnNamespace := c.String("fnNamespace")
 
-	cron := c.String("cron")
+	cronSpec := c.String("cron")
-	if len(cron) == 0 {
+	if len(cronSpec) == 0 {
-		fatal("Need a cron spec like '0 30 * * *', '@every 1h30m', or '@hourly'; use --cron")
+		fatal("Need a cron spec like '0 30 * * * *', '@every 1h30m', or '@hourly'; use --cron")
 	}
 
 	tt := &crd.TimeTrigger{
@@ -53,7 +81,7 @@ func ttCreate(c *cli.Context) error {
 			Namespace: fnNamespace,
 		},
 		Spec: fission.TimeTriggerSpec{
-			Cron: cron,
+			Cron: cronSpec,
 			FunctionReference: fission.FunctionReference{
 				Type: fission.FunctionReferenceTypeFunctionName,
 				Name: fnName,
@@ -73,6 +101,10 @@ func ttCreate(c *cli.Context) error {
 	checkErr(err, "create Time trigger")
 
 	fmt.Printf("trigger '%v' created\n", name)
+
+	err = getCronNextNActivationTime(cronSpec, getAPITimeInfo(client), 1)
+	checkErr(err, "pass cron spec examination")
+
 	return err
 }
 
@@ -118,6 +150,10 @@ func ttUpdate(c *cli.Context) error {
 	checkErr(err, "update Time trigger")
 
 	fmt.Printf("trigger '%v' updated\n", ttName)
+
+	err = getCronNextNActivationTime(newCron, getAPITimeInfo(client), 1)
+	checkErr(err, "pass cron spec examination")
+
 	return nil
 }
 
@@ -157,3 +193,18 @@ func ttList(c *cli.Context) error {
 
 	return nil
 }
+
+func ttTest(c *cli.Context) error {
+	client := getClient(c.GlobalString("server"))
+
+	round := c.Int("round")
+	cronSpec := c.String("cron")
+	if len(cronSpec) == 0 {
+		fatal("Need a cron spec like '0 30 * * * *', '@every 1h30m', or '@hourly'; use --cron")
+	}
+
+	err := getCronNextNActivationTime(cronSpec, getAPITimeInfo(client), round)
+	checkErr(err, "pass cron spec examination")
+
+	return nil
+}

info.go

@@ -18,6 +18,7 @@ package fission
 
 import (
 	"encoding/json"
+	"time"
 )
 
 var (
@@ -27,22 +28,53 @@ var (
 )
 
 type (
-	Info struct {
+	BuildMeta struct {
 		GitCommit string `json:"GitCommit,omitempty"`
 		BuildDate string `json:"BuildDate,omitempty"`
 		Version   string `json:"Version,omitempty"`
 	}
+
+	Time struct {
+		Timezone    string    `json:"Timezone,omitempty"`
+		CurrentTime time.Time `json:"CurrentTime,omitempty"`
+	}
+
+	ServerInfo struct {
+		Build      BuildMeta `json:"Build,omitempty"`
+		ServerTime Time      `json:"ServerTime,omitempty"`
+	}
 )
 
-func VersionInfo() Info {
+func BuildInfo() BuildMeta {
-	return Info{
+	return BuildMeta{
 		GitCommit: GitCommit,
 		BuildDate: BuildDate,
 		Version:   Version,
 	}
 }
 
-func (info Info) String() string {
+func (info BuildMeta) String() string {
+	v, _ := json.Marshal(info)
+	return string(v)
+}
+
+func TimeInfo() Time {
+	t := time.Now()
+	zone, _ := t.Local().Zone()
+	return Time{
+		Timezone:    zone,
+		CurrentTime: t,
+	}
+}
+
+func ApiInfo() ServerInfo {
+	return ServerInfo{
+		Build:      BuildInfo(),
+		ServerTime: TimeInfo(),
+	}
+}
+
+func (info ServerInfo) String() string {
 	v, _ := json.Marshal(info)
 	return string(v)
 }