k8s: remove unused filter functionality from k8sclient.CiliumLogs

Currently, the logic to retrieve all logs from Cilium Pods is implemented using
`bufio.Scanner`. This might result in errors for long  loglines.

```
Error reading Cilium logs: error reading cilium-agent logs for kube-system/cilium-c2sx7: bufio.Scanner: token too long
```

The only reason to use the `bufio.Scanner` is the support to filter the logs by
a given regular expression. But this functionality is not used.

Therefore, this commit removes the filter functionality and the usage of `bufio.Scanner`.

Signed-off-by: Marco Hofstetter <[email protected]>

clustermesh/clustermesh.go

@@ -15,7 +15,6 @@ import (
 	"io"
 	"net"
 	"os"
-	"regexp"
 	"sort"
 	"strconv"
 	"strings"
@@ -75,7 +74,7 @@ type k8sClusterMeshImplementation interface {
 	CreateCiliumExternalWorkload(ctx context.Context, cew *ciliumv2.CiliumExternalWorkload, opts metav1.CreateOptions) (*ciliumv2.CiliumExternalWorkload, error)
 	DeleteCiliumExternalWorkload(ctx context.Context, name string, opts metav1.DeleteOptions) error
 	ListCiliumEndpoints(ctx context.Context, namespace string, options metav1.ListOptions) (*ciliumv2.CiliumEndpointList, error)
-	CiliumLogs(ctx context.Context, namespace, pod string, since time.Time, filter *regexp.Regexp) (string, error)
+	CiliumLogs(ctx context.Context, namespace, pod string, since time.Time) (string, error)
 }
 
 type K8sClusterMesh struct {

connectivity/check/policy.go

@@ -657,7 +657,7 @@ func (t *Test) deletePolicies(ctx context.Context) error {
 // filter is applied on each line of output.
 func (t *Test) CiliumLogs(ctx context.Context) {
 	for _, pod := range t.Context().ciliumPods {
-		log, err := pod.K8sClient.CiliumLogs(ctx, pod.Pod.Namespace, pod.Pod.Name, t.startTime, nil)
+		log, err := pod.K8sClient.CiliumLogs(ctx, pod.Pod.Namespace, pod.Pod.Name, t.startTime)
 		if err != nil {
 			t.Fatalf("Error reading Cilium logs: %s", err)
 		}

k8s/client.go

@@ -4,19 +4,22 @@
 package k8s
 
 import (
-	"bufio"
 	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
 	"io"
 	"net"
 	"net/url"
-	"regexp"
 	"strings"
 	"time"
 
 	"github.com/blang/semver/v4"
+	"github.com/cilium/cilium/api/v1/models"
+	ciliumv2 "github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2"
+	ciliumv2alpha1 "github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2alpha1"
+	ciliumClientset "github.com/cilium/cilium/pkg/k8s/client/clientset/versioned"
+	"github.com/cilium/cilium/pkg/versioncheck"
 	"helm.sh/helm/v3/pkg/action"
 	"helm.sh/helm/v3/pkg/cli/output"
 	appsv1 "k8s.io/api/apps/v1"
@@ -41,12 +44,6 @@ import (
 	"k8s.io/client-go/rest"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 
-	"github.com/cilium/cilium/api/v1/models"
-	ciliumv2 "github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2"
-	ciliumv2alpha1 "github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2alpha1"
-	ciliumClientset "github.com/cilium/cilium/pkg/k8s/client/clientset/versioned"
-	"github.com/cilium/cilium/pkg/versioncheck"
-
 	"github.com/cilium/cilium-cli/defaults"
 )
 
@@ -282,7 +279,6 @@ func (c *Client) GetRaw(ctx context.Context, path string) (string, error) {
 		return "", err
 	}
 	return string(response), nil
-
 }
 
 func (c *Client) CreatePod(ctx context.Context, namespace string, pod *corev1.Pod, opts metav1.CreateOptions) (*corev1.Pod, error) {
@@ -305,12 +301,7 @@ func (c *Client) PodLogs(namespace, name string, opts *corev1.PodLogOptions) *re
 	return c.Clientset.CoreV1().Pods(namespace).GetLogs(name, opts)
 }
 
-// separator for locating the start of the next log message. Sometimes
-// logs may span multiple lines, locate the timestamp, log level and
-// msg that always start a new log message
-var logSplitter = regexp.MustCompile(`\r?\n[^ ]+ level=[[:alpha:]]+ msg=`)
-
-func (c *Client) CiliumLogs(ctx context.Context, namespace, pod string, since time.Time, filter *regexp.Regexp) (string, error) {
+func (c *Client) CiliumLogs(ctx context.Context, namespace, pod string, since time.Time) (string, error) {
 	opts := &corev1.PodLogOptions{
 		Container:  defaults.AgentContainerName,
 		Timestamps: true,
@@ -323,37 +314,12 @@ func (c *Client) CiliumLogs(ctx context.Context, namespace, pod string, since ti
 	}
 	defer podLogs.Close()
 
-	buf := new(bytes.Buffer)
-	scanner := bufio.NewScanner(podLogs)
-	scanner.Split(func(data []byte, atEOF bool) (advance int, token []byte, err error) {
-		if atEOF && len(data) == 0 {
-			return 0, nil, nil
-		}
-		// find the full log line separator
-		loc := logSplitter.FindIndex(data)
-		if loc != nil {
-			// Locate '\n', advance just past it
-			nl := loc[0] + bytes.IndexByte(data[loc[0]:loc[1]], '\n') + 1
-			return nl, data[:nl], nil
-		} else if atEOF {
-			// EOF, return all we have
-			return len(data), data, nil
-		}
-		// Nothing to return
-		return 0, nil, nil
-	})
-
-	for scanner.Scan() {
-		if filter != nil && !filter.Match(scanner.Bytes()) {
-			continue
-		}
-		buf.Write(scanner.Bytes())
-	}
-	err = scanner.Err()
+	log, err := io.ReadAll(podLogs)
 	if err != nil {
-		err = fmt.Errorf("error reading cilium-agent logs for %s/%s: %w", namespace, pod, err)
+		return "", fmt.Errorf("error reading log: %w", err)
 	}
-	return buf.String(), err
+
+	return string(log), err
 }
 
 func (c *Client) ListServices(ctx context.Context, namespace string, options metav1.ListOptions) (*corev1.ServiceList, error) {
@@ -916,7 +882,6 @@ func (c *Client) GetHelmValues(_ context.Context, releaseName string, namespace
 		return "", fmt.Errorf("unable to parse helm values from release %s: %w", releaseName, err)
 	}
 	return valuesBuf.String(), nil
-
 }
 
 // GetHelmMetadata is the function for cilium cli sysdump to collect the helm metadata from the release directly
@@ -942,7 +907,6 @@ func (c *Client) GetHelmMetadata(_ context.Context, releaseName string, namespac
 		return "", fmt.Errorf("unable to parse helm metas from release %s: %w", releaseName, err)
 	}
 	return buf.String(), nil
-
 }
 
 // CreateEphemeralContainer will create a EphemeralContainer (debug container) in the specified pod.

status/k8s.go

@@ -8,7 +8,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"regexp"
 	"strings"
 	"sync"
 	"time"
@@ -70,7 +69,7 @@ type k8sImplementation interface {
 	GetDeployment(ctx context.Context, namespace, name string, options metav1.GetOptions) (*appsv1.Deployment, error)
 	ListPods(ctx context.Context, namespace string, options metav1.ListOptions) (*corev1.PodList, error)
 	ListCiliumEndpoints(ctx context.Context, namespace string, options metav1.ListOptions) (*ciliumv2.CiliumEndpointList, error)
-	CiliumLogs(ctx context.Context, namespace, pod string, since time.Time, filter *regexp.Regexp) (string, error)
+	CiliumLogs(ctx context.Context, namespace, pod string, since time.Time) (string, error)
 }
 
 func NewK8sStatusCollector(client k8sImplementation, params K8sStatusParameters) (*K8sStatusCollector, error) {
@@ -544,10 +543,11 @@ func (k *K8sStatusCollector) status(ctx context.Context) *Status {
 			}
 			status.HelmChartVersion = release.Chart.Metadata.Version
 			return nil
-		}})
+		},
+	})
 
 	// for the sake of sanity, don't get pod logs more than once
-	var agentLogsOnce = sync.Once{}
+	agentLogsOnce := sync.Once{}
 	err := k.podStatus(ctx, status, defaults.AgentDaemonSetName, defaults.AgentPodSelector, func(_ context.Context, status *Status, name string, pod *corev1.Pod) {
 		if pod.Status.Phase == corev1.PodRunning {
 			// extract container status
@@ -591,7 +591,7 @@ func (k *K8sStatusCollector) status(ctx context.Context) *Status {
 									dyingGasp = strings.TrimSpace(terminated.Message)
 								} else {
 									agentLogsOnce.Do(func() { // in a sync.Once so we don't waste time retrieving lots of logs
-										logs, err := k.client.CiliumLogs(ctx, pod.Namespace, pod.Name, terminated.FinishedAt.Time.Add(-2*time.Minute), nil)
+										logs, err := k.client.CiliumLogs(ctx, pod.Namespace, pod.Name, terminated.FinishedAt.Time.Add(-2*time.Minute))
 										if err == nil && logs != "" {
 											dyingGasp = strings.TrimSpace(logs)
 										}
@@ -621,7 +621,6 @@ func (k *K8sStatusCollector) status(ctx context.Context) *Status {
 			})
 		}
 	})
-
 	if err != nil {
 		status.CollectionError(err)
 	}

status/k8s_test.go

@@ -6,7 +6,6 @@ package status
 import (
 	"context"
 	"fmt"
-	"regexp"
 	"testing"
 	"time"
 
@@ -144,7 +143,7 @@ func (c *k8sStatusMockClient) ListCiliumEndpoints(_ context.Context, _ string, o
 	return c.ciliumEndpointList[options.LabelSelector], nil
 }
 
-func (c *k8sStatusMockClient) CiliumLogs(_ context.Context, _, _ string, _ time.Time, _ *regexp.Regexp) (string, error) {
+func (c *k8sStatusMockClient) CiliumLogs(_ context.Context, _, _ string, _ time.Time) (string, error) {
 	return "[error] a sample cilium-agent error message", nil
 }