Merged changes from master to k8s branch

Dockerfile

@@ -1,4 +1,4 @@
-FROM quay.io/vektorcloud/go:1.11
+FROM quay.io/vektorcloud/go:1.12
 
 RUN apk add --no-cache make
 

README.md

@@ -20,7 +20,7 @@ Fetch the [latest release](https://github.com/bcicen/ctop/releases) for your pla
 #### Linux
 
 ```bash
-sudo wget https://github.com/bcicen/ctop/releases/download/v0.7.1/ctop-0.7.1-linux-amd64 -O /usr/local/bin/ctop
+sudo wget https://github.com/bcicen/ctop/releases/download/v0.7.2/ctop-0.7.2-linux-amd64 -O /usr/local/bin/ctop
 sudo chmod +x /usr/local/bin/ctop
 ```
 
@@ -31,7 +31,7 @@ brew install ctop
 ```
 or
 ```bash
-sudo curl -Lo /usr/local/bin/ctop https://github.com/bcicen/ctop/releases/download/v0.7.1/ctop-0.7.1-darwin-amd64
+sudo curl -Lo /usr/local/bin/ctop https://github.com/bcicen/ctop/releases/download/v0.7.2/ctop-0.7.2-darwin-amd64
 sudo chmod +x /usr/local/bin/ctop
 ```
 
@@ -40,7 +40,7 @@ sudo chmod +x /usr/local/bin/ctop
 ```bash
 docker run --rm -ti \
   --name=ctop \
-  -v /var/run/docker.sock:/var/run/docker.sock \
+  --volume /var/run/docker.sock:/var/run/docker.sock:ro \
   quay.io/vektorlab/ctop:latest
 ```
 
@@ -70,6 +70,7 @@ Option | Description
 -s  | select initial container sort field
 -scale-cpu	| show cpu as % of system total
 -v	| output version information and exit
+-shell | specify shell (default: sh)
 
 ### Keybindings
 
@@ -84,6 +85,7 @@ s | Select container sort field
 r | Reverse container sort order
 o | Open single view
 l | View container logs (`t` to toggle timestamp when open)
+e | Exec Shell
 S | Save current configuration to file
 q | Quit ctop
 

VERSION

@@ -1 +1 @@
-0.7.1
+0.7.2

_docs/connectors.md

@@ -1,4 +1,4 @@
-# connectors
+# Connectors
 
 `ctop` comes with the below native connectors, enabled via the `--connector` option.
 

_docs/status.md

@@ -0,0 +1,30 @@
+# Status Indicator
+
+The `ctop` grid view provides a compact status indicator to convey container state
+
+<img width="200px" src="img/status.png" alt="ctop"/>
+
+### Status
+
+<span align="center">
+
+Appearance | Description
+--- | ---
+red | container is stopped
+green | container is running
+▮▮ | container is paused
+
+</span>
+
+### Health
+If the container is configured with a health check, a `+` will appear next to the indicator
+
+<span align="center">
+
+Appearance | Description
+--- | ---
+red | health check in failed state
+yellow | health check in starting state
+green | health check in OK state
+
+</span>

config/param.go

@@ -17,6 +17,11 @@ var params = []*Param{
 		Val:   "state",
 		Label: "Kubernetes namespace for monitoring",
 	},
+	&Param{
+		Key:   "shell",
+		Val:   "sh",
+		Label: "Shell",
+	},
 }
 
 type Param struct {
@@ -35,7 +40,7 @@ func Get(k string) *Param {
 	return &Param{} // default
 }
 
-// Get Param value by key
+// GetVal gets Param value by key
 func GetVal(k string) string {
 	return Get(k).Val
 }

config/switch.go

@@ -35,7 +35,7 @@ type Switch struct {
 	Label string
 }
 
-// Return Switch by key
+// GetSwitch returns Switch by key
 func GetSwitch(k string) *Switch {
 	for _, sw := range GlobalSwitches {
 		if sw.Key == k {
@@ -45,7 +45,7 @@ func GetSwitch(k string) *Switch {
 	return &Switch{} // default
 }
 
-// Return Switch value by key
+// GetSwitchVal returns Switch value by key
 func GetSwitchVal(k string) bool {
 	return GetSwitch(k).Val
 }

connector/docker.go

@@ -17,27 +17,45 @@ type Docker struct {
 	client       *api.Client
 	containers   map[string]*container.Container
 	needsRefresh chan string // container IDs requiring refresh
+	closed       chan struct{}
 	lock         sync.RWMutex
 }
 
-func NewDocker() Connector {
+func NewDocker() (Connector, error) {
 	// init docker client
 	client, err := api.NewClientFromEnv()
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
 	cm := &Docker{
 		client:       client,
 		containers:   make(map[string]*container.Container),
 		needsRefresh: make(chan string, 60),
+		closed:       make(chan struct{}),
 		lock:         sync.RWMutex{},
 	}
+
+	// query info as pre-flight healthcheck
+	info, err := client.Info()
+	if err != nil {
+		return nil, err
+	}
+
+	log.Debugf("docker-connector ID: %s", info.ID)
+	log.Debugf("docker-connector Driver: %s", info.Driver)
+	log.Debugf("docker-connector Images: %d", info.Images)
+	log.Debugf("docker-connector Name: %s", info.Name)
+	log.Debugf("docker-connector ServerVersion: %s", info.ServerVersion)
+
 	go cm.Loop()
 	cm.refreshAll()
 	go cm.watchEvents()
-	return cm
+	return cm, nil
 }
 
+// Docker implements Connector
+func (cm *Docker) Wait() struct{} { return <-cm.closed }
+
 // Docker events watcher
 func (cm *Docker) watchEvents() {
 	log.Info("docker event listener starting")
@@ -60,6 +78,8 @@ func (cm *Docker) watchEvents() {
 			cm.delByID(e.ID)
 		}
 	}
+	log.Info("docker event listener exited")
+	close(cm.closed)
 }
 
 func portsFormat(ports map[api.Port][]api.PortBinding) string {
@@ -114,7 +134,7 @@ func (cm *Docker) inspect(id string) *api.Container {
 	c, err := cm.client.InspectContainer(id)
 	if err != nil {
 		if _, ok := err.(*api.NoSuchContainer); !ok {
-			log.Errorf(err.Error())
+			log.Errorf("%s (%T)", err.Error(), err)
 		}
 	}
 	return c
@@ -125,7 +145,8 @@ func (cm *Docker) refreshAll() {
 	opts := api.ListContainersOptions{All: true}
 	allContainers, err := cm.client.ListContainers(opts)
 	if err != nil {
-		panic(err)
+		log.Errorf("%s (%T)", err.Error(), err)
+		return
 	}
 
 	for _, i := range allContainers {
@@ -137,13 +158,18 @@ func (cm *Docker) refreshAll() {
 }
 
 func (cm *Docker) Loop() {
-	for id := range cm.needsRefresh {
-		c := cm.MustGet(id)
-		cm.refresh(c)
+	for {
+		select {
+		case id := <-cm.needsRefresh:
+			c := cm.MustGet(id)
+			cm.refresh(c)
+		case <-cm.closed:
+			return
+		}
 	}
 }
 
-// Get a single container, creating one anew if not existing
+// MustGet gets a single container, creating one anew if not existing
 func (cm *Docker) MustGet(id string) *container.Container {
 	c, ok := cm.Get(id)
 	// append container struct for new containers
@@ -161,7 +187,7 @@ func (cm *Docker) MustGet(id string) *container.Container {
 	return c
 }
 
-// Get a single container, by ID
+// Docker implements Connector
 func (cm *Docker) Get(id string) (*container.Container, bool) {
 	cm.lock.Lock()
 	c, ok := cm.containers[id]
@@ -177,7 +203,7 @@ func (cm *Docker) delByID(id string) {
 	log.Infof("removed dead container: %s", id)
 }
 
-// Return array of all containers, sorted by field
+// Docker implements Connector
 func (cm *Docker) All() (containers container.Containers) {
 	cm.lock.Lock()
 	for _, c := range cm.containers {

connector/main.go

@@ -3,17 +3,89 @@ package connector
 import (
 	"fmt"
 	"sort"
+	"sync"
+	"time"
 
 	"github.com/bcicen/ctop/container"
 	"github.com/bcicen/ctop/logging"
 )
 
 var (
 	log     = logging.Init()
-	enabled = make(map[string]func() Connector)
+	enabled = make(map[string]ConnectorFn)
 )
 
-// return names for all enabled connectors on the current platform
+type ConnectorFn func() (Connector, error)
+
+type Connector interface {
+	// All returns a pre-sorted container.Containers of all discovered containers
+	All() container.Containers
+	// Get returns a single container.Container by ID
+	Get(string) (*container.Container, bool)
+	// Wait waits for the underlying connection to be lost before returning
+	Wait() struct{}
+}
+
+// ConnectorSuper provides initial connection and retry on failure for
+// an undlerying Connector type
+type ConnectorSuper struct {
+	conn   Connector
+	connFn ConnectorFn
+	err    error
+	lock   sync.RWMutex
+}
+
+func NewConnectorSuper(connFn ConnectorFn) *ConnectorSuper {
+	cs := &ConnectorSuper{
+		connFn: connFn,
+		err:    fmt.Errorf("connecting..."),
+	}
+	go cs.loop()
+	return cs
+}
+
+// Get returns the underlying Connector, or nil and an error
+// if the Connector is not yet initialized or is disconnected.
+func (cs *ConnectorSuper) Get() (Connector, error) {
+	cs.lock.RLock()
+	defer cs.lock.RUnlock()
+	if cs.err != nil {
+		return nil, cs.err
+	}
+	return cs.conn, nil
+}
+
+func (cs *ConnectorSuper) setError(err error) {
+	cs.lock.Lock()
+	defer cs.lock.Unlock()
+	cs.err = err
+}
+
+func (cs *ConnectorSuper) loop() {
+	const interval = 3
+	for {
+		log.Infof("initializing connector")
+
+		conn, err := cs.connFn()
+		if err != nil {
+			cs.setError(err)
+			log.Errorf("failed to initialize connector: %s (%T)", err, err)
+			log.Errorf("retrying in %ds", interval)
+			time.Sleep(interval * time.Second)
+		} else {
+			cs.conn = conn
+			cs.setError(nil)
+			log.Infof("successfully initialized connector")
+
+			// wait until connection closed
+			cs.conn.Wait()
+			cs.setError(fmt.Errorf("attempting to reconnect..."))
+			log.Infof("connector closed")
+		}
+	}
+}
+
+// Enabled returns names for all enabled connectors on the current platform
 func Enabled() (a []string) {
 	for k, _ := range enabled {
 		a = append(a, k)
@@ -22,14 +94,11 @@ func Enabled() (a []string) {
 	return a
 }
 
-func ByName(s string) (Connector, error) {
+// ByName returns a ConnectorSuper for a given name, or error if the connector
+// does not exists on the current platform
+func ByName(s string) (*ConnectorSuper, error) {
 	if cfn, ok := enabled[s]; ok {
-		return cfn(), nil
+		return NewConnectorSuper(cfn), nil
 	}
 	return nil, fmt.Errorf("invalid connector type \"%s\"", s)
 }
-
-type Connector interface {
-	All() container.Containers
-	Get(string) (*container.Container, bool)
-}