feat(agent): add status controller

internal/agent/agent.go

@@ -38,6 +38,7 @@ func (a *Agent) Run(ctx context.Context) error {
 	client := client.New(a.serverURL, client.WithToken(token))
 
 	ctx = withClient(ctx, client)
+	ctx = withThumbprint(ctx, a.thumbprint)
 
 	tick := func() {
 		logger.Debug(ctx, "registering agent")

internal/agent/context.go

@@ -10,7 +10,8 @@ import (
 type contextKey string
 
 const (
-	contextKeyClient contextKey = "client"
+	contextKeyClient     contextKey = "client"
+	contextKeyThumbprint contextKey = "thumbprint"
 )
 
 func withClient(ctx context.Context, client *client.Client) context.Context {
@@ -25,3 +26,16 @@ func Client(ctx context.Context) *client.Client {
 
 	return client
 }
+
+func withThumbprint(ctx context.Context, thumbprint string) context.Context {
+	return context.WithValue(ctx, contextKeyThumbprint, thumbprint)
+}
+
+func Thumbprint(ctx context.Context) string {
+	thumbprint, ok := ctx.Value(contextKeyThumbprint).(string)
+	if !ok {
+		panic(errors.New("could not retrieve thumbprint from context"))
+	}
+
+	return thumbprint
+}

internal/agent/controller/status/controller.go

@@ -0,0 +1,138 @@
+package status
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"sync/atomic"
+
+	"forge.cadoles.com/Cadoles/emissary/internal/agent"
+	"forge.cadoles.com/Cadoles/emissary/internal/datastore"
+	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/api"
+	"gitlab.com/wpetit/goweb/logger"
+)
+
+type Status struct {
+	Agent        *datastore.Agent
+	Connected    bool
+	Claimed      bool
+	Thumbprint   string
+	ServerURL    string
+	ClaimURL     string
+	AgentURL     string
+	AgentVersion string
+}
+
+type Controller struct {
+	status       *atomic.Value
+	server       *atomic.Value
+	addr         string
+	claimURL     string
+	agentURL     string
+	agentVersion string
+}
+
+// Name implements node.Controller.
+func (c *Controller) Name() string {
+	return "status-controller"
+}
+
+// Reconcile implements node.Controller.
+func (c *Controller) Reconcile(ctx context.Context, state *agent.State) error {
+	cl := agent.Client(ctx)
+	thumbprint := agent.Thumbprint(ctx)
+
+	connected := true
+
+	agent, err := cl.GetAgent(ctx, state.AgentID())
+	if err != nil {
+		logger.Error(ctx, "could not get agent", logger.E(errors.WithStack(err)))
+		var apiErr *api.Error
+		if errors.As(err, &apiErr) {
+			switch apiErr.Code {
+			case api.ErrCodeForbidden:
+				// Contact is ok but agent may be not claimed yet
+			default:
+				connected = false
+			}
+		} else {
+			connected = false
+		}
+	}
+
+	claimed := agent != nil && agent.TenantID != nil
+	var agentID datastore.AgentID
+	if agent != nil {
+		agentID = agent.ID
+	}
+
+	c.status.Store(Status{
+		Agent:        agent,
+		Connected:    connected,
+		Claimed:      claimed,
+		Thumbprint:   thumbprint,
+		ServerURL:    cl.ServerURL(),
+		ClaimURL:     fmt.Sprintf(c.claimURL, thumbprint),
+		AgentURL:     fmt.Sprintf(c.agentURL, agentID),
+		AgentVersion: c.agentVersion,
+	})
+
+	if err := c.startServer(ctx); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (c *Controller) startServer(ctx context.Context) error {
+	server := c.getServer()
+	if server != nil {
+		return nil
+	}
+
+	server = &http.Server{
+		Addr: c.addr,
+		Handler: &Handler{
+			status: c.status,
+		},
+	}
+
+	go func() {
+		defer c.setServer(nil)
+
+		if err := server.ListenAndServe(); err != nil {
+			logger.Error(ctx, "could not start server", logger.E(errors.WithStack(err)))
+		}
+	}()
+
+	c.setServer(server)
+
+	return nil
+}
+
+func (c *Controller) setServer(s *http.Server) {
+	c.server.Store(s)
+}
+
+func (c *Controller) getServer() *http.Server {
+	server, ok := c.server.Load().(*http.Server)
+	if !ok {
+		return nil
+	}
+
+	return server
+}
+
+func NewController(addr string, claimURL string, agentURL string, agentVersion string) *Controller {
+	return &Controller{
+		addr:         addr,
+		claimURL:     claimURL,
+		agentURL:     agentURL,
+		agentVersion: agentVersion,
+		status:       &atomic.Value{},
+		server:       &atomic.Value{},
+	}
+}
+
+var _ agent.Controller = &Controller{}

internal/agent/controller/status/handler.go

@@ -0,0 +1,74 @@
+package status
+
+import (
+	"embed"
+	"html/template"
+	"io/fs"
+	"net/http"
+	"sync"
+	"sync/atomic"
+
+	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/logger"
+)
+
+//go:embed templates/*.gotpl
+var templates embed.FS
+
+//go:embed public/*
+var public embed.FS
+
+type Handler struct {
+	status *atomic.Value
+
+	public    http.Handler
+	templates *template.Template
+
+	init    sync.Once
+	initErr error
+}
+
+// ServeHTTP implements http.Handler.
+func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	h.init.Do(func() {
+		root, err := fs.Sub(public, "public")
+		if err != nil {
+			h.initErr = errors.WithStack(err)
+			return
+		}
+
+		h.public = http.FileServer(http.FS(root))
+
+		tmpl, err := template.ParseFS(templates, "templates/*.gotpl")
+		if err != nil {
+			h.initErr = errors.WithStack(err)
+			return
+		}
+
+		h.templates = tmpl
+	})
+	if h.initErr != nil {
+		logger.Error(r.Context(), "could not initialize handler", logger.E(h.initErr))
+		http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+
+		return
+	}
+
+	switch r.URL.Path {
+	case "/":
+		h.serveIndex(w, r)
+	default:
+		h.public.ServeHTTP(w, r)
+	}
+}
+
+func (h *Handler) serveIndex(w http.ResponseWriter, r *http.Request) {
+	data := h.status.Load()
+
+	if err := h.templates.ExecuteTemplate(w, "index.html.gotpl", data); err != nil {
+		logger.Error(r.Context(), "could not render template", logger.E(errors.WithStack(err)))
+		return
+	}
+}
+
+var _ http.Handler = &Handler{}

internal/agent/controller/status/templates/index.html.gotpl

@@ -0,0 +1,145 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <link rel="icon" type="image/x-icon" href="logo.png">
+    <title>Status | Emissary Agent</title>
+    <link rel="stylesheet" href="bulma-0.9.4.min.css">
+    <style>
+        body {
+            background-color: #f7f7f7f7;
+        }
+        .logo {
+            left: 50%;
+            position: absolute;
+            margin-left: -40px;
+            width: 100px;
+            margin-top: -120px
+        }
+        .card {
+            position:relative;
+            padding-top: 70px;
+            margin-top: 70px;
+        }
+        #qrcode {
+            display: flex;
+            flex-direction: row;
+            justify-content: center;
+        }
+    </style>
+    {{if or .Connected ( not .Claimed ) }}
+    <script type="text/javascript" src="qrcode.min.js"></script>
+    {{ end }}
+</head>
+<body>
+    <section class="section">
+        <div class="container">
+            <div class="column">
+                <div class="has-text-centered">
+                    <h1 class="title is-size-1 ">Emissary</h1>
+                    <h2 class="subtitle is-size-4">Agent Status</h2>
+                </div>
+                <div class="box card">
+                    <img class="logo" src="logo.png" />
+                    <div class="overflow:hidden">
+                        <div class="level is-mobile" style="margin-top:-50px">
+                            <div class="level-left">
+                                <div class="level-item is-size-4-tablet is-size-7-mobile">
+                                    <strong class="mr-2">Connected:</strong>{{if .Connected }}<span class="has-text-success">✔</span>{{ else }}<span class="has-text-danger">✕</span>{{ end }}
+                                </div>
+                            </div>
+                            <div class="level-right">
+                                <div class="level-item is-size-4-tablet is-size-7-mobile">
+                                    <strong class="mr-2">Claimed:</strong>{{if .Claimed }}<span class="has-text-success">✔</span>{{ else }}<span class="has-text-warning">✕</span>{{ end }}
+                                </div>
+                            </div>
+                        </div>
+                        {{ if and .Connected ( not .Claimed ) }}
+                        <h3 class="is-size-3 mt-4">Claim your agent</h3>
+                        <p class="has-text-centered">
+                            You can claim your agent by clicking the following link:<br />
+                            <a class="button is-link is-medium mt-3" href="{{ .ClaimURL }}" target="_blank" rel="nofollow">Claim me</a><br />
+                        </p>
+                        <p class="has-text-centered mt-3">
+                            You can also scan the following QRCode:
+                            <div id="qrcode" class="mt-3" data-claim-url="{{ .ClaimURL }}"></div>
+                            <script type="text/javascript">
+                                (function() {
+                                    const qrCodeElement = document.getElementById("qrcode");
+                                    const claimUrl = qrCodeElement.dataset.claimUrl;
+                                    new QRCode(qrCodeElement, claimUrl);
+                                }())
+                            </script>
+                        </p>
+                        {{ end }}
+                        {{ if and .Connected .Claimed }}
+                        <h3 class="is-size-3 mt-4">Manage your agent</h3>
+                        <p class="has-text-centered">
+                            You can manage your agent by clicking the following link:<br />
+                            <a class="button is-link is-medium mt-3" href="{{ .AgentURL }}" target="_blank" rel="nofollow">Manage me</a><br />
+                        </p>
+                        <p class="has-text-centered mt-3">
+                            You can also scan the following QRCode:
+                            <div id="qrcode" class="mt-3" data-agent-url="{{ .AgentURL }}"></div>
+                            <script type="text/javascript">
+                               (function() {
+                                    const qrCodeElement = document.getElementById("qrcode");
+                                    const agentUrl = qrCodeElement.dataset.agentUrl;
+                                    new QRCode(qrCodeElement, agentUrl);
+                               }())
+                            </script>
+                        </p>
+                        {{ end }}
+                        <h3 class="is-size-3 mt-4">Informations</h3>
+                        <div class="table-container">
+                            <table class="table is-fullwidth">
+                                <thead>
+                                    <tr>
+                                        <th>Attribute</th>
+                                        <th>Value</th>
+                                    </tr>
+                                </thead>
+                                <tbody>
+                                    <tr>
+                                        <td>Thumbprint</td>
+                                        <td><code>{{ .Thumbprint }}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Agent ID</td>
+                                        <td><code>{{ if .Agent }}{{ .Agent.ID }}{{ else }}unknown{{end}}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Agent Label</td>
+                                        <td><code>{{ with .Agent }}{{ if .Label }}{{ .Label }}{{ else }}empty{{end}}{{ else }}unknown{{end}}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Last server contact</td>
+                                        <td><code>{{ if .Agent }}{{ .Agent.ContactedAt }}{{ else }}unknown{{end}}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Server URL</td>
+                                        <td><code>{{ .ServerURL }}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Claim URL</td>
+                                        <td><code>{{ .ClaimURL }}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Agent URL</td>
+                                        <td><code>{{ if .Agent }}{{ .AgentURL }}{{ else }}unknown{{end}}</code></td>
+                                    </tr>
+                                    <tr>
+                                        <td>Agent version</td>
+                                        <td><code>{{ .AgentVersion }}</code></td>
+                                    </tr>
+                                </tbody>
+                            </table>
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
+    </section>
+</body>
+</html>

internal/command/agent/run.go

@@ -10,6 +10,7 @@ import (
 	"forge.cadoles.com/Cadoles/emissary/internal/agent/controller/persistence"
 	"forge.cadoles.com/Cadoles/emissary/internal/agent/controller/proxy"
 	"forge.cadoles.com/Cadoles/emissary/internal/agent/controller/spec"
+	"forge.cadoles.com/Cadoles/emissary/internal/agent/controller/status"
 	"forge.cadoles.com/Cadoles/emissary/internal/agent/metadata"
 	"forge.cadoles.com/Cadoles/emissary/internal/agent/metadata/collector/buildinfo"
 	"forge.cadoles.com/Cadoles/emissary/internal/agent/metadata/collector/shell"
@@ -94,6 +95,15 @@ func RunCommand() *cli.Command {
 				))
 			}
 
+			if ctrlConf.Status.Enabled {
+				controllers = append(controllers, status.NewController(
+					string(ctrlConf.Status.Address),
+					string(ctrlConf.Status.ClaimURL),
+					string(ctrlConf.Status.AgentURL),
+					string(ctx.String("projectVersion")),
+				))
+			}
+
 			key, err := jwk.LoadOrGenerate(string(conf.Agent.PrivateKeyPath), jwk.DefaultKeySize)
 			if err != nil {
 				return errors.WithStack(err)

internal/config/agent.go

@@ -24,6 +24,7 @@ type ControllersConfig struct {
 	App         AppControllerConfig         `yaml:"app"`
 	SysUpgrade  SysUpgradeControllerConfig  `yaml:"sysupgrade"`
 	MDNS        MDNSControllerConfig        `yaml:"mdns"`
+	Status      StatusControllerConfig      `yaml:"status"`
 }
 
 type PersistenceControllerConfig struct {
@@ -60,6 +61,13 @@ type MDNSControllerConfig struct {
 	Enabled InterpolatedBool `yaml:"enabled"`
 }
 
+type StatusControllerConfig struct {
+	Enabled  InterpolatedBool   `yaml:"enabled"`
+	Address  InterpolatedString `yaml:"address"`
+	ClaimURL InterpolatedString `yaml:"claimURL"`
+	AgentURL InterpolatedString `yaml:"agentURL"`
+}
+
 func NewDefaultAgentConfig() AgentConfig {
 	return AgentConfig{
 		ServerURL:              "http://127.0.0.1:3000",
@@ -94,6 +102,12 @@ func NewDefaultAgentConfig() AgentConfig {
 			MDNS: MDNSControllerConfig{
 				Enabled: true,
 			},
+			Status: StatusControllerConfig{
+				Enabled:  true,
+				Address:  ":42521",
+				ClaimURL: "http://localhost:3001/claim/%s",
+				AgentURL: "http://localhost:3001/agents/%v",
+			},
 		},
 		Collectors: []ShellCollectorConfig{
 			{

misc/packaging/common/config-agent.yml

@@ -62,6 +62,16 @@ agent:
         - sh
         - -c
         - source /etc/openwrt_release && echo "$DISTRIB_ID-$DISTRIB_RELEASE-$DISTRIB_REVISION"
+    
+    # Status controller configuration
+    status:
+      enabled: true
+      # Status page listening address
+      address: :42521
+      # Agent claim URL template (see Emissary HQ)
+      claimURL: http://127.0.0.1:3001/claim/%v
+      # Agent URL template (see Emissary HQ)
+      agentURL: http://127.0.0.1:3001/agents/%v
   
   # Collectors configuration
   collectors:

modd.conf

@@ -1,5 +1,6 @@
 **/*.go
 internal/**/*.json
+**/*.gotpl
 modd.conf
 tmp/config.yml
 .env {

pkg/client/client.go

@@ -18,6 +18,10 @@ type Client struct {
 	serverURL   string
 }
 
+func (c *Client) ServerURL() string {
+	return c.serverURL
+}
+
 func (c *Client) apiGet(ctx context.Context, path string, result any, funcs ...OptionFunc) error {
 	if err := c.apiDo(ctx, http.MethodGet, path, nil, result, funcs...); err != nil {
 		return errors.WithStack(err)