k3d/cli/commands.go
Andy Zhou a0eb69b73e Allow the volume argument to be specified multiple times
Most k3d arguments are using in "stringSlice" style, allowing the
argument to supplied multiple times. Currently "volume" is an exception
to this style, require multiple arguments to be supplied in a single
argument, separated by comma.

This commit improve the k3d usability by improve the consistency of its
argument style.
2019-05-15 09:35:07 -07:00

432 lines
12 KiB
Go

package run
/*
* This file contains the "backend" functionality for the CLI commands (and flags)
*/
import (
"bytes"
"context"
"errors"
"fmt"
"io/ioutil"
"log"
"os"
"strconv"
"strings"
"time"
"github.com/docker/docker/api/types/filters"
"github.com/docker/docker/api/types"
"github.com/docker/docker/client"
"github.com/urfave/cli"
)
const (
defaultRegistry = "docker.io"
defaultServerCount = 1
)
// CheckTools checks if the docker API server is responding
func CheckTools(c *cli.Context) error {
log.Print("Checking docker...")
ctx := context.Background()
docker, err := client.NewEnvClient()
if err != nil {
return err
}
ping, err := docker.Ping(ctx)
if err != nil {
return fmt.Errorf("ERROR: checking docker failed\n%+v", err)
}
log.Printf("SUCCESS: Checking docker succeeded (API: v%s)\n", ping.APIVersion)
return nil
}
// CreateCluster creates a new single-node cluster container and initializes the cluster directory
func CreateCluster(c *cli.Context) error {
if err := CheckClusterName(c.String("name")); err != nil {
return err
}
// define image
image := c.String("image")
if c.IsSet("version") {
// TODO: --version to be deprecated
log.Println("[WARNING] The `--version` flag will be deprecated soon, please use `--image rancher/k3s:<version>` instead")
if c.IsSet("image") {
// version specified, custom image = error (to push deprecation of version flag)
log.Fatalln("[ERROR] Please use `--image <image>:<version>` instead of --image and --version")
} else {
// version specified, default image = ok (until deprecation of version flag)
image = fmt.Sprintf("%s:%s", strings.Split(image, ":")[0], c.String("version"))
}
}
if len(strings.Split(image, "/")) <= 2 {
// fallback to default registry
image = fmt.Sprintf("%s/%s", defaultRegistry, image)
}
// create cluster network
networkID, err := createClusterNetwork(c.String("name"))
if err != nil {
return err
}
log.Printf("Created cluster network with ID %s", networkID)
if c.IsSet("timeout") && !c.IsSet("wait") {
return errors.New("Cannot use --timeout flag without --wait flag")
}
// environment variables
env := []string{"K3S_KUBECONFIG_OUTPUT=/output/kubeconfig.yaml"}
if c.IsSet("env") || c.IsSet("e") {
env = append(env, c.StringSlice("env")...)
}
k3sClusterSecret := ""
if c.Int("workers") > 0 {
k3sClusterSecret = fmt.Sprintf("K3S_CLUSTER_SECRET=%s", GenerateRandomString(20))
env = append(env, k3sClusterSecret)
}
// k3s server arguments
// TODO: --port will soon be --api-port since we want to re-use --port for arbitrary port mappings
if c.IsSet("port") {
log.Println("INFO: As of v2.0.0 --port will be used for arbitrary port mapping. Please use --api-port/-a instead for configuring the Api Port")
}
k3sServerArgs := []string{"--https-listen-port", c.String("api-port")}
if c.IsSet("server-arg") || c.IsSet("x") {
k3sServerArgs = append(k3sServerArgs, c.StringSlice("server-arg")...)
}
// new port map
portmap, err := mapNodesToPortSpecs(c.StringSlice("publish"), GetAllContainerNames(c.String("name"), defaultServerCount, c.Int("workers")))
if err != nil {
log.Fatal(err)
}
// create the server
log.Printf("Creating cluster [%s]", c.String("name"))
dockerID, err := createServer(
c.GlobalBool("verbose"),
image,
c.String("api-port"),
k3sServerArgs,
env,
c.String("name"),
c.StringSlice("volume"),
portmap,
)
if err != nil {
log.Printf("ERROR: failed to create cluster\n%+v", err)
delErr := DeleteCluster(c)
if delErr != nil {
return delErr
}
os.Exit(1)
}
ctx := context.Background()
docker, err := client.NewEnvClient()
if err != nil {
return err
}
// Wait for k3s to be up and running if wanted.
// We're simply scanning the container logs for a line that tells us that everything's up and running
// TODO: also wait for worker nodes
start := time.Now()
timeout := time.Duration(c.Int("timeout")) * time.Second
for c.IsSet("wait") {
// not running after timeout exceeded? Rollback and delete everything.
if timeout != 0 && !time.Now().After(start.Add(timeout)) {
err := DeleteCluster(c)
if err != nil {
return err
}
return errors.New("Cluster creation exceeded specified timeout")
}
// scan container logs for a line that tells us that the required services are up and running
out, err := docker.ContainerLogs(ctx, dockerID, types.ContainerLogsOptions{ShowStdout: true, ShowStderr: true})
if err != nil {
out.Close()
return fmt.Errorf("ERROR: couldn't get docker logs for %s\n%+v", c.String("name"), err)
}
buf := new(bytes.Buffer)
nRead, _ := buf.ReadFrom(out)
out.Close()
output := buf.String()
if nRead > 0 && strings.Contains(string(output), "Running kubelet") {
break
}
time.Sleep(1 * time.Second)
}
// create the directory where we will put the kubeconfig file by default (when running `k3d get-config`)
// TODO: this can probably be moved to `k3d get-config` or be removed in a different approach
createClusterDir(c.String("name"))
// spin up the worker nodes
// TODO: do this concurrently in different goroutines
if c.Int("workers") > 0 {
k3sWorkerArgs := []string{}
env := []string{k3sClusterSecret}
log.Printf("Booting %s workers for cluster %s", strconv.Itoa(c.Int("workers")), c.String("name"))
for i := 0; i < c.Int("workers"); i++ {
workerID, err := createWorker(
c.GlobalBool("verbose"),
image,
k3sWorkerArgs,
env,
c.String("name"),
c.StringSlice("volume"),
i,
c.String("api-port"),
portmap,
c.Int("port-auto-offset"),
)
if err != nil {
return fmt.Errorf("ERROR: failed to create worker node for cluster %s\n%+v", c.String("name"), err)
}
log.Printf("Created worker with ID %s\n", workerID)
}
}
log.Printf("SUCCESS: created cluster [%s]", c.String("name"))
log.Printf(`You can now use the cluster with:
export KUBECONFIG="$(%s get-kubeconfig --name='%s')"
kubectl cluster-info`, os.Args[0], c.String("name"))
return nil
}
// DeleteCluster removes the containers belonging to a cluster and its local directory
func DeleteCluster(c *cli.Context) error {
// operate on one or all clusters
clusters := make(map[string]cluster)
if !c.Bool("all") {
cluster, err := getCluster(c.String("name"))
if err != nil {
return err
}
clusters[c.String("name")] = cluster
} else {
clusterMap, err := getClusters()
if err != nil {
return fmt.Errorf("ERROR: `--all` specified, but no clusters were found\n%+v", err)
}
// copy clusterMap
for k, v := range clusterMap {
clusters[k] = v
}
}
// remove clusters one by one instead of appending all names to the docker command
// this allows for more granular error handling and logging
for _, cluster := range clusters {
log.Printf("Removing cluster [%s]", cluster.name)
if len(cluster.workers) > 0 {
// TODO: this could be done in goroutines
log.Printf("...Removing %d workers\n", len(cluster.workers))
for _, worker := range cluster.workers {
if err := removeContainer(worker.ID); err != nil {
log.Println(err)
continue
}
}
}
log.Println("...Removing server")
deleteClusterDir(cluster.name)
if err := removeContainer(cluster.server.ID); err != nil {
return fmt.Errorf("ERROR: Couldn't remove server for cluster %s\n%+v", cluster.name, err)
}
if err := deleteClusterNetwork(cluster.name); err != nil {
log.Printf("WARNING: couldn't delete cluster network for cluster %s\n%+v", cluster.name, err)
}
log.Printf("SUCCESS: removed cluster [%s]", cluster.name)
}
return nil
}
// StopCluster stops a running cluster container (restartable)
func StopCluster(c *cli.Context) error {
// operate on one or all clusters
clusters := make(map[string]cluster)
if !c.Bool("all") {
cluster, err := getCluster(c.String("name"))
if err != nil {
return err
}
clusters[c.String("name")] = cluster
} else {
clusterMap, err := getClusters()
if err != nil {
return fmt.Errorf("ERROR: `--all` specified, but no clusters were found\n%+v", err)
}
// copy clusterMap
for k, v := range clusterMap {
clusters[k] = v
}
}
ctx := context.Background()
docker, err := client.NewEnvClient()
if err != nil {
return fmt.Errorf("ERROR: couldn't create docker client\n%+v", err)
}
// remove clusters one by one instead of appending all names to the docker command
// this allows for more granular error handling and logging
for _, cluster := range clusters {
log.Printf("Stopping cluster [%s]", cluster.name)
if len(cluster.workers) > 0 {
log.Printf("...Stopping %d workers\n", len(cluster.workers))
for _, worker := range cluster.workers {
if err := docker.ContainerStop(ctx, worker.ID, nil); err != nil {
log.Println(err)
continue
}
}
}
log.Println("...Stopping server")
if err := docker.ContainerStop(ctx, cluster.server.ID, nil); err != nil {
return fmt.Errorf("ERROR: Couldn't stop server for cluster %s\n%+v", cluster.name, err)
}
log.Printf("SUCCESS: Stopped cluster [%s]", cluster.name)
}
return nil
}
// StartCluster starts a stopped cluster container
func StartCluster(c *cli.Context) error {
// operate on one or all clusters
clusters := make(map[string]cluster)
if !c.Bool("all") {
cluster, err := getCluster(c.String("name"))
if err != nil {
return err
}
clusters[c.String("name")] = cluster
} else {
clusterMap, err := getClusters()
if err != nil {
return fmt.Errorf("ERROR: `--all` specified, but no clusters were found\n%+v", err)
}
// copy clusterMap
for k, v := range clusterMap {
clusters[k] = v
}
}
ctx := context.Background()
docker, err := client.NewEnvClient()
if err != nil {
return fmt.Errorf("ERROR: couldn't create docker client\n%+v", err)
}
// remove clusters one by one instead of appending all names to the docker command
// this allows for more granular error handling and logging
for _, cluster := range clusters {
log.Printf("Starting cluster [%s]", cluster.name)
log.Println("...Starting server")
if err := docker.ContainerStart(ctx, cluster.server.ID, types.ContainerStartOptions{}); err != nil {
return fmt.Errorf("ERROR: Couldn't start server for cluster %s\n%+v", cluster.name, err)
}
if len(cluster.workers) > 0 {
log.Printf("...Starting %d workers\n", len(cluster.workers))
for _, worker := range cluster.workers {
if err := docker.ContainerStart(ctx, worker.ID, types.ContainerStartOptions{}); err != nil {
log.Println(err)
continue
}
}
}
log.Printf("SUCCESS: Started cluster [%s]", cluster.name)
}
return nil
}
// ListClusters prints a list of created clusters
func ListClusters(c *cli.Context) error {
printClusters(c.Bool("all"))
return nil
}
// GetKubeConfig grabs the kubeconfig from the running cluster and prints the path to stdout
func GetKubeConfig(c *cli.Context) error {
ctx := context.Background()
docker, err := client.NewEnvClient()
if err != nil {
return err
}
filters := filters.NewArgs()
filters.Add("label", "app=k3d")
filters.Add("label", fmt.Sprintf("cluster=%s", c.String("name")))
filters.Add("label", "component=server")
server, err := docker.ContainerList(ctx, types.ContainerListOptions{
Filters: filters,
})
if err != nil {
return fmt.Errorf("Failed to get server container for cluster %s\n%+v", c.String("name"), err)
}
if len(server) == 0 {
return fmt.Errorf("No server container for cluster %s", c.String("name"))
}
// get kubeconfig file from container and read contents
reader, _, err := docker.CopyFromContainer(ctx, server[0].ID, "/output/kubeconfig.yaml")
if err != nil {
return fmt.Errorf("ERROR: couldn't copy kubeconfig.yaml from server container %s\n%+v", server[0].ID, err)
}
defer reader.Close()
readBytes, err := ioutil.ReadAll(reader)
if err != nil {
return fmt.Errorf("ERROR: couldn't read kubeconfig from container\n%+v", err)
}
// create destination kubeconfig file
clusterDir, err := getClusterDir(c.String("name"))
destPath := fmt.Sprintf("%s/kubeconfig.yaml", clusterDir)
if err != nil {
return err
}
kubeconfigfile, err := os.Create(destPath)
if err != nil {
return fmt.Errorf("ERROR: couldn't create kubeconfig.yaml in %s\n%+v", clusterDir, err)
}
defer kubeconfigfile.Close()
// write to file, skipping the first 512 bytes which contain file metadata and trimming any NULL characters
_, err = kubeconfigfile.Write(bytes.Trim(readBytes[512:], "\x00"))
if err != nil {
return fmt.Errorf("ERROR: couldn't write to kubeconfig.yaml\n%+v", err)
}
// output kubeconfig file path to stdout
fmt.Println(destPath)
return nil
}