fix: not saving etcd revision (#10671)

apisix/core/config_etcd.lua

@@ -132,53 +132,57 @@ local function do_run_watch(premature)
         return
     end
 
-    local local_conf, err = config_local.local_conf()
-    if not local_conf then
-        error("no local conf: " .. err)
-    end
-    watch_ctx.prefix = local_conf.etcd.prefix .. "/"
+    -- the main watcher first start
+    if watch_ctx.started == false then
+        local local_conf, err = config_local.local_conf()
+        if not local_conf then
+            error("no local conf: " .. err)
+        end
+        watch_ctx.prefix = local_conf.etcd.prefix .. "/"
+        watch_ctx.timeout = local_conf.etcd.watch_timeout
 
-    watch_ctx.cli, err = get_etcd()
-    if not watch_ctx.cli then
-        error("failed to create etcd instance: " .. string(err))
-    end
+        watch_ctx.cli, err = get_etcd()
+        if not watch_ctx.cli then
+            error("failed to create etcd instance: " .. string(err))
+        end
 
-    local rev = 0
-    if loaded_configuration then
-        local _, res = next(loaded_configuration)
-        if res then
-            rev = tonumber(res.headers["X-Etcd-Index"])
-            assert(rev > 0, 'invalid res.headers["X-Etcd-Index"]')
+        local rev = 0
+        if loaded_configuration then
+            local _, res = next(loaded_configuration)
+            if res then
+                rev = tonumber(res.headers["X-Etcd-Index"])
+                assert(rev > 0, 'invalid res.headers["X-Etcd-Index"]')
+            end
         end
-    end
 
-    if rev == 0 then
-        while true do
-            local res, err = watch_ctx.cli:get(watch_ctx.prefix)
-            if not res then
-                log.error("etcd get: ", err)
-                ngx_sleep(3)
-            else
-                rev = tonumber(res.body.header.revision)
-                break
+        if rev == 0 then
+            while true do
+                local res, err = watch_ctx.cli:get(watch_ctx.prefix)
+                if not res then
+                    log.error("etcd get: ", err)
+                    ngx_sleep(3)
+                else
+                    rev = tonumber(res.body.header.revision)
+                    break
+                end
             end
         end
-    end
 
-    watch_ctx.rev = rev + 1
-    watch_ctx.started = true
+        watch_ctx.rev = rev + 1
+        watch_ctx.started = true
 
-    log.info("main etcd watcher started, revision=", watch_ctx.rev)
+        log.info("main etcd watcher initialised, revision=", watch_ctx.rev)
 
-    if watch_ctx.wait_init then
-        for _, sema in pairs(watch_ctx.wait_init) do
-            sema:post()
+        if watch_ctx.wait_init then
+            for _, sema in pairs(watch_ctx.wait_init) do
+                sema:post()
+            end
+            watch_ctx.wait_init = nil
         end
-        watch_ctx.wait_init = nil
     end
 
     local opts = {}
-    opts.timeout = 50 -- second
+    opts.timeout = watch_ctx.timeout or 50 -- second
     opts.need_cancel = true
     opts.start_revision = watch_ctx.rev
 

conf/config-default.yaml

@@ -672,7 +672,8 @@ deployment:                    # Deployment configurations
     host:                         # Set etcd address(es) in the same etcd cluster.
       - "http://127.0.0.1:2379"   # If TLS is enabled for etcd, use https://127.0.0.1:2379.
     prefix: /apisix               # Set etcd prefix.
-    timeout: 30                   # Set timeout in seconds.
+    timeout: 30                   # The timeout when connect/read/write to etcd, Set timeout in seconds.
+    watch_timeout: 50             # The timeout when watch etcd
     # resync_delay: 5             # Set resync time in seconds after a sync failure.
                                   # The actual resync time would be resync_delay plus 50% random jitter.
     # health_check_timeout: 10    # Set timeout in seconds for etcd health check.

t/core/config_etcd.t

@@ -486,3 +486,33 @@ passed
 hello world
 passed
 {"error_msg":"404 Route Not Found"}
+
+
+
+=== TEST 13: the main watcher should be initialised once
+--- yaml_config
+apisix:
+  node_listen: 1984
+deployment:
+  role: traditional
+  role_traditional:
+    config_provider: etcd
+  admin:
+    admin_key: null
+  etcd:
+    host:
+      - "http://127.0.0.1:2379"
+    watch_timeout: 1
+--- config
+    location /t {
+        content_by_lua_block {
+            ngx.sleep(1)
+        }
+    }
+--- request
+GET /t
+--- grep_error_log eval
+qr/main etcd watcher initialised, revision=/
+--- grep_error_log_out
+main etcd watcher initialised, revision=
+main etcd watcher initialised, revision=