From 3cd11d6bc4c0ee2ac1937b17c702c460e422a8ce Mon Sep 17 00:00:00 2001
From: Henry Dollman <hank@henrygd.me>
Date: Tue, 12 Nov 2024 11:59:56 -0500
Subject: [PATCH] improve podman support (#211)

---
 beszel/internal/agent/agent.go               |  2 +-
 beszel/internal/agent/docker.go              | 55 ++++++++++++++------
 beszel/internal/entities/system/system.go    |  1 +
 beszel/site/src/components/routes/system.tsx | 19 ++++---
 beszel/site/src/types.d.ts                   |  2 +
 5 files changed, 56 insertions(+), 23 deletions(-)

diff --git a/beszel/internal/agent/agent.go b/beszel/internal/agent/agent.go
index a381bc0..6190b10 100644
--- a/beszel/internal/agent/agent.go
+++ b/beszel/internal/agent/agent.go
@@ -73,7 +73,7 @@ func (a *Agent) Run(pubKey []byte, addr string) {
 	a.initializeSystemInfo()
 	a.initializeDiskInfo()
 	a.initializeNetIoStats()
-	a.dockerManager = newDockerManager()
+	a.dockerManager = newDockerManager(a)
 
 	// initialize GPU manager
 	if os.Getenv("GPU") == "true" {
diff --git a/beszel/internal/agent/docker.go b/beszel/internal/agent/docker.go
index 178951c..31f68ec 100644
--- a/beszel/internal/agent/docker.go
+++ b/beszel/internal/agent/docker.go
@@ -25,18 +25,23 @@ type dockerManager struct {
 	apiContainerList    *[]container.ApiInfo        // List of containers from Docker API
 	containerStatsMap   map[string]*container.Stats // Keeps track of container stats
 	validIds            map[string]struct{}         // Map of valid container ids, used to prune invalid containers from containerStatsMap
+	goodDockerVersion   bool                        // Whether docker version is at least 25.0.0 (one-shot works correctly)
 }
 
 // Add goroutine to the queue
 func (d *dockerManager) queue() {
-	d.sem <- struct{}{}
 	d.wg.Add(1)
+	if d.goodDockerVersion {
+		d.sem <- struct{}{}
+	}
 }
 
 // Remove goroutine from the queue
 func (d *dockerManager) dequeue() {
-	<-d.sem
 	d.wg.Done()
+	if d.goodDockerVersion {
+		<-d.sem
+	}
 }
 
 // Returns stats for all running containers
@@ -75,6 +80,7 @@ func (dm *dockerManager) getDockerStats() ([]*container.Stats, error) {
 		go func() {
 			defer dm.dequeue()
 			err := dm.updateContainerStats(ctr)
+			// if error, delete from map and add to failed list to retry
 			if err != nil {
 				dm.containerStatsMutex.Lock()
 				delete(dm.containerStatsMap, ctr.IdShort)
@@ -89,11 +95,10 @@ func (dm *dockerManager) getDockerStats() ([]*container.Stats, error) {
 	// retry failed containers separately so we can run them in parallel (docker 24 bug)
 	if len(failedContainters) > 0 {
 		slog.Debug("Retrying failed containers", "count", len(failedContainters))
-		// time.Sleep(time.Millisecond * 1100)
 		for _, ctr := range failedContainters {
-			dm.wg.Add(1)
+			dm.queue()
 			go func() {
-				defer dm.wg.Done()
+				defer dm.dequeue()
 				err = dm.updateContainerStats(ctr)
 				if err != nil {
 					slog.Error("Error getting container stats", "err", err)
@@ -201,12 +206,13 @@ func (dm *dockerManager) deleteContainerStatsSync(id string) {
 	delete(dm.containerStatsMap, id)
 }
 
-// Creates a new http client for Docker API
-func newDockerManager() *dockerManager {
-	dockerHost := "unix:///var/run/docker.sock"
-	if dockerHostEnv, exists := os.LookupEnv("DOCKER_HOST"); exists {
-		slog.Info("DOCKER_HOST", "host", dockerHostEnv)
-		dockerHost = dockerHostEnv
+// Creates a new http client for Docker or Podman API
+func newDockerManager(a *Agent) *dockerManager {
+	dockerHost, exists := os.LookupEnv("DOCKER_HOST")
+	if exists {
+		slog.Info("DOCKER_HOST", "host", dockerHost)
+	} else {
+		dockerHost = getDockerHost()
 	}
 
 	parsedURL, err := url.Parse(dockerHost)
@@ -251,11 +257,15 @@ func newDockerManager() *dockerManager {
 			Transport: transport,
 		},
 		containerStatsMap: make(map[string]*container.Stats),
+		sem:               make(chan struct{}, 5),
 	}
 
-	// Make sure sem is initialized
-	concurrency := 200
-	defer func() { dockerClient.sem = make(chan struct{}, concurrency) }()
+	// If using podman, return client
+	if strings.Contains(dockerHost, "podman") {
+		a.systemInfo.Podman = true
+		dockerClient.goodDockerVersion = true
+		return dockerClient
+	}
 
 	// Check docker version
 	// (versions before 25.0.0 have a bug with one-shot which requires all requests to be made in one batch)
@@ -273,9 +283,22 @@ func newDockerManager() *dockerManager {
 
 	// if version > 24, one-shot works correctly and we can limit concurrent operations
 	if dockerVersion, err := semver.Parse(versionInfo.Version); err == nil && dockerVersion.Major > 24 {
-		concurrency = 5
+		dockerClient.goodDockerVersion = true
+	} else {
+		slog.Info(fmt.Sprintf("Docker %s is outdated. Upgrade if possible. See https://github.com/henrygd/beszel/issues/58", versionInfo.Version))
 	}
-	slog.Debug("Docker", "version", versionInfo.Version, "concurrency", concurrency)
 
 	return dockerClient
 }
+
+// Test docker / podman sockets and return if one exists
+func getDockerHost() string {
+	scheme := "unix://"
+	socks := []string{"/var/run/docker.sock", "/run/user/1000/podman/podman.sock", "/run/podman/podman.sock"}
+	for _, sock := range socks {
+		if _, err := os.Stat(sock); err == nil {
+			return scheme + sock
+		}
+	}
+	return scheme + socks[0]
+}
diff --git a/beszel/internal/entities/system/system.go b/beszel/internal/entities/system/system.go
index c6f7363..3cabcce 100644
--- a/beszel/internal/entities/system/system.go
+++ b/beszel/internal/entities/system/system.go
@@ -74,6 +74,7 @@ type Info struct {
 	DiskPct       float64 `json:"dp"`
 	Bandwidth     float64 `json:"b"`
 	AgentVersion  string  `json:"v"`
+	Podman        bool    `json:"p,omitempty"`
 }
 
 // Final data structure to return to the hub
diff --git a/beszel/site/src/components/routes/system.tsx b/beszel/site/src/components/routes/system.tsx
index 67d10e0..1ee02c7 100644
--- a/beszel/site/src/components/routes/system.tsx
+++ b/beszel/site/src/components/routes/system.tsx
@@ -86,6 +86,13 @@ async function getStats<T>(collection: string, system: SystemRecord, chartTime:
 	})
 }
 
+function dockerOrPodman(str: string, system: SystemRecord) {
+	if (system.info.p) {
+		str = str.replace("docker", "podman").replace("Docker", "Podman")
+	}
+	return str
+}
+
 export default function SystemDetail({ name }: { name: string }) {
 	const direction = useStore($direction)
 	const { _ } = useLingui()
@@ -385,7 +392,7 @@ export default function SystemDetail({ name }: { name: string }) {
 						<ChartCard
 							empty={dataEmpty}
 							grid={grid}
-							title={t`Docker CPU Usage`}
+							title={dockerOrPodman(t`Docker CPU Usage`, system)}
 							description={t`Average CPU utilization of containers`}
 							cornerEl={containerFilterBar}
 						>
@@ -406,8 +413,8 @@ export default function SystemDetail({ name }: { name: string }) {
 						<ChartCard
 							empty={dataEmpty}
 							grid={grid}
-							title={t`Docker Memory Usage`}
-							description={t`Memory usage of docker containers`}
+							title={dockerOrPodman(t`Docker Memory Usage`, system)}
+							description={dockerOrPodman(t`Memory usage of docker containers`, system)}
 							cornerEl={containerFilterBar}
 						>
 							<ContainerChart chartData={chartData} chartName="mem" dataKey="m" unit=" MB" />
@@ -447,8 +454,8 @@ export default function SystemDetail({ name }: { name: string }) {
 						>
 							<ChartCard
 								empty={dataEmpty}
-								title={t`Docker Network I/O`}
-								description={t`Network traffic of docker containers`}
+								title={dockerOrPodman(t`Docker Network I/O`, system)}
+								description={dockerOrPodman(t`Network traffic of docker containers`, system)}
 								cornerEl={containerFilterBar}
 							>
 								{/* @ts-ignore */}
@@ -649,7 +656,7 @@ function ChartCard({
 				<CardDescription>{description}</CardDescription>
 				{cornerEl && <div className="relative py-1 block sm:w-44 sm:absolute sm:top-2.5 sm:end-3.5">{cornerEl}</div>}
 			</CardHeader>
-			<div className="ps-0 w-[calc(100%-1.6em)] h-52 relative">
+			<div className="ps-0 w-[calc(100%-1.5em)] h-52 relative">
 				{<Spinner msg={empty ? t`Waiting for enough records to display` : undefined} />}
 				{isIntersecting && children}
 			</div>
diff --git a/beszel/site/src/types.d.ts b/beszel/site/src/types.d.ts
index 90a7e78..62886ea 100644
--- a/beszel/site/src/types.d.ts
+++ b/beszel/site/src/types.d.ts
@@ -34,6 +34,8 @@ export interface SystemInfo {
 	b: number
 	/** agent version */
 	v: string
+	/** system is using podman */
+	p?: boolean
 }
 
 export interface SystemStats {