bin: reload: filter: Provide additional validator before loading filt…

…er plugins .cb_pre_run should be provided for filter plugins that is easily to get faulty statuses. For now, it's going to be used only for filter_lua. Signed-off-by: Hiroshi Hatake <[email protected]>
fluent · Nov 4, 2023 · fc8b8e8 · fc8b8e8
1 parent 8a4fe62
commit fc8b8e8
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Showing 5 changed files with 46 additions and 15 deletions.
diff --git a/include/fluent-bit/flb_filter.h b/include/fluent-bit/flb_filter.h
@@ -64,6 +64,7 @@ struct flb_filter_plugin {
     struct flb_config_map *config_map;
 
     /* Callbacks */
+    int (*cb_pre_run) (struct flb_filter_instance *, struct flb_config *, void *);
     int (*cb_init) (struct flb_filter_instance *, struct flb_config *, void *);
     int (*cb_filter) (const void *, size_t,
                       const char *, int,

diff --git a/include/fluent-bit/flb_reload.h b/include/fluent-bit/flb_reload.h
@@ -25,9 +25,12 @@
 #include <fluent-bit/flb_config.h>
 #include <fluent-bit/flb_config_format.h>
 
-#define FLB_RELOAD_IDLE 0
-#define FLB_RELOAD_IN_PROGRESS 1
-#define FLB_RELOAD_ABORTED     2
+#define FLB_RELOAD_IDLE             0
+#define FLB_RELOAD_IN_PROGRESS      1
+#define FLB_RELOAD_ABORTED         -1
+#define FLB_RELOAD_HALTED          -2
+#define FLB_RELOAD_NOT_ENABLED     -3
+#define FLB_RELOAD_INVALID_CONTEXT -4
 
 int flb_reload_property_check_all(struct flb_config *config);
 int flb_reload_reconstruct_cf(struct flb_cf *src_cf, struct flb_cf *dest_cf);

diff --git a/src/flb_filter.c b/src/flb_filter.c
@@ -577,6 +577,15 @@ int flb_filter_init(struct flb_config *config, struct flb_filter_instance *ins)
         return 0;
     }
 
+    /* Run pre_run callback for the filter */
+    if (p->cb_pre_run) {
+        ret = p->cb_pre_run(ins, config, ins->data);
+        if (ret != 0) {
+            flb_error("Failed pre_run callback on filter %s", ins->name);
+            return -1;
+        }
+    }
+
     /* Initialize the input */
     if (p->cb_init) {
         ret = p->cb_init(ins, config, ins->data);

diff --git a/src/flb_reload.c b/src/flb_reload.c
@@ -31,6 +31,7 @@
 #include <fluent-bit/flb_kv.h>
 #include <fluent-bit/flb_utils.h>
 #include <fluent-bit/flb_plugin.h>
+#include <fluent-bit/flb_reload.h>
 
 #include <cfl/cfl.h>
 #include <cfl/cfl_sds.h>
@@ -128,6 +129,7 @@ static int flb_filter_propery_check_all(struct flb_config *config)
     struct mk_list *tmp;
     struct mk_list *head;
     struct flb_filter_instance *ins;
+    struct flb_filter_plugin *p;
 
     /* Iterate all active input instance plugins */
     mk_list_foreach_safe(head, tmp, &config->filters) {
@@ -145,6 +147,17 @@ static int flb_filter_propery_check_all(struct flb_config *config)
             return -1;
         }
 
+        /* Check actual values with additional validator */
+        p = ins->p;
+        /* Run pre_run callback for the filter */
+        if (p->cb_pre_run) {
+            ret = p->cb_pre_run(ins, config, ins->data);
+            if (ret != 0) {
+                flb_error("Failed pre_run callback on filter %s", ins->name);
+                return -1;
+            }
+        }
+
         /* destroy config map (will be recreated at flb_start) */
         if (ins->config_map) {
             flb_config_map_destroy(ins->config_map);
@@ -205,7 +218,7 @@ int flb_reload_property_check_all(struct flb_config *config)
     /* Check properties of filter plugins */
     ret = flb_filter_propery_check_all(config);
     if (ret == -1) {
-        flb_error("[reload] check properties for filter plugins is failed");
+        flb_error("[reload] check properties and additonal vaildations for filter plugins is failed");
 
         return -1;
     }
@@ -371,13 +384,13 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
 
     if (ctx == NULL) {
         flb_error("[reload] given flb context is NULL");
-        return -2;
+        return FLB_RELOAD_INVALID_CONTEXT;
     }
 
     old_config = ctx->config;
     if (old_config->enable_hot_reload != FLB_TRUE) {
         flb_warn("[reload] hot reloading is not enabled");
-        return -3;
+        return FLB_RELOAD_NOT_ENABLED;
     }
 
     if (old_config->ensure_thread_safety_on_hot_reloading) {
@@ -391,7 +404,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
      */
     new_cf = flb_cf_create();
     if (!new_cf) {
-        return -1;
+        return FLB_RELOAD_HALTED;
     }
 
     flb_info("reloading instance pid=%lu tid=%p", (long unsigned) getpid(), pthread_self());
@@ -406,7 +419,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
             }
             flb_cf_destroy(new_cf);
             flb_error("[reload] reconstruct cf failed");
-            return -1;
+            return FLB_RELOAD_HALTED;
         }
     }
 
@@ -419,7 +432,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
         flb_cf_destroy(new_cf);
         flb_error("[reload] creating flb context is failed. Reloading is halted");
 
-        return -1;
+        return FLB_RELOAD_HALTED;
     }
 
     new_config = new_ctx->config;
@@ -446,7 +459,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
         if (!new_cf) {
             flb_sds_destroy(file);
 
-            return -1;
+            return FLB_RELOAD_HALTED;
         }
     }
 
@@ -462,7 +475,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
             flb_destroy(new_ctx);
             flb_error("[reload] reloaded config is invalid. Reloading is halted");
 
-            return -1;
+            return FLB_RELOAD_HALTED;
         }
     }
 
@@ -476,7 +489,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
 
         flb_error("[reload] reloaded config format is invalid. Reloading is halted");
 
-        return -1;
+        return FLB_RELOAD_HALTED;
     }
 
     /* Validate plugin properites before fluent-bit stops the old context. */
@@ -489,7 +502,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
 
         flb_error("[reload] reloaded config is invalid. Reloading is halted");
 
-        return -1;
+        return FLB_RELOAD_HALTED;
     }
 
     /* Delete the original context of config format before replacing
@@ -518,7 +531,7 @@ int flb_reload(flb_ctx_t *ctx, struct flb_cf *cf_opts)
 
         flb_error("[reload] loaded configuration contains error(s). Reloading is aborted");
 
-        return -1;
+        return FLB_RELOAD_ABORTED;
     }
 
     /* Store the new value of hot reloading times into the new context */

diff --git a/src/fluent-bit.c b/src/fluent-bit.c
@@ -1400,9 +1400,14 @@ int flb_main(int argc, char **argv)
                 flb_bin_restarting = FLB_RELOAD_IDLE;
             }
             else {
-                flb_bin_restarting = FLB_RELOAD_ABORTED;
+                flb_bin_restarting = ret;
             }
         }
+
+        if (flb_bin_restarting == FLB_RELOAD_HALTED) {
+            sleep(1);
+            flb_bin_restarting = FLB_RELOAD_IDLE;
+        }
     }
 
     if (exit_signal) {