feat: add configuration_hash in /status in dbless (#8214)

* feat: add configuration_hash in dbless /status * Update spec/02-integration/08-status_api/01-core_routes_spec.lua Co-authored-by: Harry <harrybagdi@gmail.com> * Update spec/02-integration/08-status_api/01-core_routes_spec.lua Co-authored-by: Harry <harrybagdi@gmail.com> * Update spec/02-integration/08-status_api/01-core_routes_spec.lua Co-authored-by: Harry <harrybagdi@gmail.com> * test(kong_routes) some syntax fixes Co-authored-by: Harry <harrybagdi@gmail.com> Co-authored-by: Vinicius Mignot <vinicius.mignot@gmail.com>
Kong · Feb 10, 2022 · 4f8c99d · 4f8c99d
1 parent d12991f
commit 4f8c99d
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Showing 4 changed files with 105 additions and 2 deletions.
diff --git a/kong/api/routes/health.lua b/kong/api/routes/health.lua
@@ -1,4 +1,5 @@
 local utils = require "kong.tools.utils"
+local declarative = require "kong.db.declarative"
 
 local find = string.find
 local select = select
@@ -11,6 +12,8 @@ local knode  = (kong and kong.node) and kong.node or
 local select = select
 local tonumber = tonumber
 local kong = kong
+local dbless = kong.configuration.database == "off"
+local data_plane_role = kong.configuration.role == "data_plane"
 
 
 return {
@@ -64,6 +67,15 @@ return {
         },
       }
 
+      -- if dbless mode is enabled we provide the current hash of the
+      -- data-plane in the status response as this enables control planes
+      -- to make decisions when something changes in the data-plane (e.g.
+      -- if the gateway gets unexpectedly restarted and its configuration
+      -- has been reset to empty).
+      if dbless or data_plane_role then
+        status_response.configuration_hash = declarative.get_current_hash()
+      end
+
       -- TODO: no way to bypass connection pool
       local ok, err = kong.db:connect()
       if not ok then

diff --git a/kong/db/declarative/init.lua b/kong/db/declarative/init.lua
@@ -44,6 +44,8 @@ local DECLARATIVE_LOCK_KEY = "declarative:lock"
 local DECLARATIVE_LOCK_TTL = 60
 local GLOBAL_QUERY_OPTS = { nulls = true, workspace = null }
 
+local EMPTY_CONFIGURATION_HASH = string.rep("0", 32)
+
 
 local declarative = {}
 
@@ -845,7 +847,14 @@ function declarative.load_into_cache(entities, meta, hash, shadow)
     return nil, err
   end
 
-  local ok, err = ngx.shared.kong:safe_set(DECLARATIVE_HASH_KEY, hash or true)
+  -- mask any default hash to indicate no hash is available.
+  if hash == EMPTY_CONFIGURATION_HASH or hash == "" then
+    hash = null
+  end
+
+  -- set the value of the configuration hash. The value can be nil, which
+  -- indicates that no configuration has been applied yet to the Gateway.
+  local ok, err = ngx.shared.kong:safe_set(DECLARATIVE_HASH_KEY, hash)
   if not ok then
     return nil, "failed to set " .. DECLARATIVE_HASH_KEY .. " in shm: " .. err
   end

diff --git a/spec/02-integration/04-admin_api/02-kong_routes_spec.lua b/spec/02-integration/04-admin_api/02-kong_routes_spec.lua
@@ -16,6 +16,7 @@ describe("Admin API - Kong routes with strategy #" .. strategy, function()
   lazy_setup(function()
     helpers.get_db_utils(nil, {}) -- runs migrations
     assert(helpers.start_kong {
+      database = strategy,
       plugins = "bundled,reports-api",
       pg_password = "hide_me"
     })
@@ -206,6 +207,47 @@ describe("Admin API - Kong routes with strategy #" .. strategy, function()
       assert.is_number(json.server.connections_writing)
       assert.is_number(json.server.connections_waiting)
       assert.is_number(json.server.total_requests)
+      assert.is_nil(json.server.configuration_hash) -- not present in DB mode, or in DBLESS mode until configuration is applied
+    end)
+
+    it("returns status info including a configuration_hash in DBLESS mode if an initial configuration has been provided #off", function()
+      -- push an initial configuration so that a configuration_hash will be present
+      local postres = assert(client:send {
+        method = "POST",
+        path = "/config",
+        body = {
+          config = [[
+          _format_version: "1.1"
+          services:
+          - host: "konghq.com"
+          ]],
+        },
+        headers = {
+          ["Content-Type"] = "application/json"
+        }
+      })
+      assert.res_status(201, postres)
+
+      -- verify the status endpoint now includes a value (other than the default) for the configuration_hash
+      local res = assert(client:send {
+        method = "GET",
+        path = "/status"
+      })
+      local body = assert.res_status(200, res)
+      local json = cjson.decode(body)
+      assert.is_table(json.database)
+      assert.is_table(json.server)
+      assert.is_boolean(json.database.reachable)
+      assert.is_number(json.server.connections_accepted)
+      assert.is_number(json.server.connections_active)
+      assert.is_number(json.server.connections_handled)
+      assert.is_number(json.server.connections_reading)
+      assert.is_number(json.server.connections_writing)
+      assert.is_number(json.server.connections_waiting)
+      assert.is_number(json.server.total_requests)
+      assert.is_string(json.configuration_hash)
+      assert.equal(32, #json.configuration_hash)
+
     end)
 
     it("database.reachable is `true` when DB connection is healthy", function()

diff --git a/spec/02-integration/08-status_api/01-core_routes_spec.lua b/spec/02-integration/08-status_api/01-core_routes_spec.lua
@@ -21,7 +21,7 @@ describe("Status API - with strategy #" .. strategy, function()
   end)
 
   describe("core", function()
-    it("/status returns status info", function()
+    it("/status returns status info without configuration_hash", function()
       local res = assert(client:send {
         method = "GET",
         path = "/status"
@@ -40,7 +40,47 @@ describe("Status API - with strategy #" .. strategy, function()
       assert.is_number(json.server.connections_writing)
       assert.is_number(json.server.connections_waiting)
       assert.is_number(json.server.total_requests)
+      assert.is_nil(json.server.configuration_hash) -- no hash in DB mode, or in DBLESS mode until configuration has been applied
     end)
+
+    it("/status starts providing a config_hash once an initial configuration has been pushed in dbless mode #off", function()
+      -- push an initial configuration so that a configuration_hash will be present
+      local postres = assert(client:send {
+        method = "POST",
+        path = "/config",
+        body = {
+          config = [[
+          _format_version: "1.1"
+          services:
+          - host = "konghq.com"
+          ]],
+        },
+        headers = {
+          ["Content-Type"] = "application/json"
+        }
+      })
+      assert.res_status(201, postres)
+
+      local res = assert(client:send {
+        method = "GET",
+        path = "/status"
+      })
+      local body = assert.res_status(200, res)
+      local json = cjson.decode(body)
+      assert.is_table(json.database)
+      assert.is_table(json.server)
+      assert.is_boolean(json.database.reachable)
+      assert.is_number(json.server.connections_accepted)
+      assert.is_number(json.server.connections_active)
+      assert.is_number(json.server.connections_handled)
+      assert.is_number(json.server.connections_reading)
+      assert.is_number(json.server.connections_writing)
+      assert.is_number(json.server.connections_waiting)
+      assert.is_number(json.server.total_requests)
+      assert.is_string(json.server.configuration_hash)
+      assert.equal(32, #json.server.configuration_hash)
+    end)
+
   end)
 
   describe("plugins", function()