From f7253ced0092a8b1aa3d1cf0b715aec3f02fd31a Mon Sep 17 00:00:00 2001
From: Phillip Whelan <phil@calyptia.com>
Date: Tue, 13 Jun 2023 10:21:51 -0400
Subject: [PATCH] in_kubernetes_events: allow listening to a single namespace
 with the 'namespace' parameter.

Signed-off-by: Phillip Whelan <phil@calyptia.com>
---
 .../in_kubernetes_events/kubernetes_events.c  | 19 ++++++++++++++++---
 .../in_kubernetes_events/kubernetes_events.h  |  1 +
 .../kubernetes_events_conf.h                  |  5 ++++-
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/plugins/in_kubernetes_events/kubernetes_events.c b/plugins/in_kubernetes_events/kubernetes_events.c
index f407d434558..1d7695aa76b 100644
--- a/plugins/in_kubernetes_events/kubernetes_events.c
+++ b/plugins/in_kubernetes_events/kubernetes_events.c
@@ -555,12 +555,19 @@ static struct flb_http_client *make_event_api_request(struct k8s_events *ctx,
     struct flb_http_client *c;
 
 
-    if (continue_token == NULL && ctx->limit_request == 0) {
+    if (continue_token == NULL && ctx->limit_request == 0 && ctx->namespace == NULL) {
         return flb_http_client(u_conn, FLB_HTTP_GET, K8S_EVENTS_KUBE_API_URI,
-                               NULL, 0, ctx->api_host, ctx->api_port, NULL, 0);
+                            NULL, 0, ctx->api_host, ctx->api_port, NULL, 0);
+    }
+
+    if (ctx->namespace == NULL) {
+        url = flb_sds_create(K8S_EVENTS_KUBE_API_URI);
+    } else {
+        url = flb_sds_create_size(strlen(K8S_EVENTS_KUBE_NAMESPACE_API_URI) + 
+                                  strlen(ctx->namespace));
+        flb_sds_printf(&url, K8S_EVENTS_KUBE_NAMESPACE_API_URI, ctx->namespace);
     }
 
-    url = flb_sds_create(K8S_EVENTS_KUBE_API_URI);
     flb_sds_cat_safe(&url, "?", 1);
     if (ctx->limit_request) {
         if (continue_token != NULL) {
@@ -874,6 +881,12 @@ static struct flb_config_map config_map[] = {
       "kubernetes retention time for events. Default: 1h"
     },
 
+    {
+      FLB_CONFIG_MAP_STR, "kube_namespace", NULL,
+      0, FLB_TRUE, offsetof(struct k8s_events, namespace),
+      "kubernetes namespace to get events from, gets event from all namespaces by default."
+    },
+
 #ifdef FLB_HAVE_SQLDB
     {
       FLB_CONFIG_MAP_STR, "db", NULL,
diff --git a/plugins/in_kubernetes_events/kubernetes_events.h b/plugins/in_kubernetes_events/kubernetes_events.h
index 7986a5014c9..1f59e480175 100644
--- a/plugins/in_kubernetes_events/kubernetes_events.h
+++ b/plugins/in_kubernetes_events/kubernetes_events.h
@@ -44,6 +44,7 @@ struct k8s_events {
     int tls_debug;
     int tls_verify;
     int kube_token_ttl;
+    flb_sds_t namespace;
 
     /* API Server end point */
     char kube_url[1024];
diff --git a/plugins/in_kubernetes_events/kubernetes_events_conf.h b/plugins/in_kubernetes_events/kubernetes_events_conf.h
index fb960b9b183..9d6b54197f1 100644
--- a/plugins/in_kubernetes_events/kubernetes_events_conf.h
+++ b/plugins/in_kubernetes_events/kubernetes_events_conf.h
@@ -29,7 +29,10 @@
 /* Kubernetes API server info */
 #define K8S_EVENTS_KUBE_API_HOST "kubernetes.default.svc"
 #define K8S_EVENTS_KUBE_API_PORT 443
-#define K8S_EVENTS_KUBE_API_URI  "/api/v1/events/"
+// /apis/events.k8s.io/v1/events
+// /apis/events.k8s.io/v1/namespaces/{namespace}/events
+#define K8S_EVENTS_KUBE_API_URI  "/api/v1/events"
+#define K8S_EVENTS_KUBE_NAMESPACE_API_URI  "/api/v1/namespaces/%s/events"
 
 /* secrets */
 #define K8S_EVENTS_KUBE_TOKEN          "/var/run/secrets/kubernetes.io/serviceaccount/token"