tests(wasm): add start/restart test for wasmtime cache

spec/02-integration/20-wasm/10-wasmtime_spec.lua

@@ -59,6 +59,111 @@ describe("#wasm wasmtime (role: " .. role .. ")", function()
                        "expected cache config file to reference the cache directory")
       end)
     end
-  end) -- cache_config
+  end) -- kong prepare
+
+  describe("kong stop/start/restart", function()
+    local conf
+    local prefix = "./wasm"
+    local log = prefix .. "/logs/error.log"
+    local status_port
+    local client
+    local cp_prefix = "./wasm-cp"
+
+    lazy_setup(function()
+      if role == "traditional" then
+        helpers.get_db_utils("postgres")
+      end
+
+      helpers.clean_prefix(prefix)
+      status_port = helpers.get_available_port()
+
+      assert(helpers.kong_exec("prepare", {
+        database = role == "data_plane" and "off" or "postgres",
+        nginx_conf = "spec/fixtures/custom_nginx.template",
+        wasm = true,
+        prefix = prefix,
+        role = role,
+        --wasm_filters_path = helpers.test_conf.wasm_filters_path,
+        wasm_filters = "tests,response_transformer",
+        cluster_cert = "spec/fixtures/kong_clustering.crt",
+        cluster_cert_key = "spec/fixtures/kong_clustering.key",
+
+        status_listen = "127.0.0.1:" .. status_port,
+        nginx_main_worker_processes = 2,
+      }))
+
+      conf = assert(helpers.get_running_conf(prefix))
+
+      -- we need to briefly spin up a control plane, or else we will get
+      -- error.log entries when our data plane tries to connect
+      if role == "data_plane" then
+        helpers.get_db_utils("postgres")
+
+        assert(helpers.start_kong({
+          database = "postgres",
+          nginx_conf = "spec/fixtures/custom_nginx.template",
+          wasm = true,
+          prefix = cp_prefix,
+          role = "control_plane",
+          wasm_filters = "tests,response_transformer",
+          cluster_cert = "spec/fixtures/kong_clustering.crt",
+          cluster_cert_key = "spec/fixtures/kong_clustering.key",
+          status_listen = "off",
+          nginx_main_worker_processes = 2,
+        }))
+      end
+    end)
+
+    lazy_teardown(function()
+      if client then
+        client:close()
+      end
+
+      helpers.stop_kong(prefix)
+
+      if role == "data_plane" then
+        helpers.stop_kong(cp_prefix)
+      end
+    end)
+
+    it("does not introduce any errors", function()
+      local function assert_no_errors()
+        assert.logfile(log).has.no.line("[error]", true, 0)
+        assert.logfile(log).has.no.line("[alert]", true, 0)
+        assert.logfile(log).has.no.line("[emerg]", true, 0)
+        assert.logfile(log).has.no.line("[crit]",  true, 0)
+      end
+
+      local function assert_kong_status(context)
+        if not client then
+          client = helpers.proxy_client(1000, status_port)
+          client.reopen = true
+        end
+
+        assert.eventually(function()
+          local res, err = client:send({ path = "/status", method = "GET" })
+          if res and res.status == 200 then
+            return true
+          end
+
+          return nil, err or "non-200 status"
+        end)
+        .is_truthy("failed waiting for kong status " .. context)
+      end
+
+      assert(helpers.start_kong(conf, nil, true))
+      assert_no_errors()
+
+      assert_kong_status("after fresh startup")
+      assert_no_errors()
+
+      assert(helpers.restart_kong(conf))
+      assert_no_errors()
+
+      assert_kong_status("after restart")
+      assert_no_errors()
+    end)
+  end) -- kong stop/start/restart
+
 end) -- wasmtime
 end -- each role