feat(db) add operation to truncate single table in new DAO

Introduces the ability to truncate a single table in the new DAO, using
either `entities:truncate()` or `db.truncate("entities")`.

Adjusts all tests to avoid truncating all tables at once deliberately.
This is done to speed up the test suite.

Note that the tests still truncate the entire database once at the
beginning of each file when they use `helpers.get_db_utils` in the
top-level `setup` directive.

kong/dao/factory.lua

@@ -168,8 +168,7 @@ local function create_legacy_wrappers(self, constraints)
 
       truncate = function(_)
         log.debug(debug.traceback("[legacy wrapper] using legacy wrapper"))
-        log.err("[legacy wrapper] truncate not implemented")
-        return nil
+        return new_dao:truncate()
       end,
     }
   end

kong/db/dao/init.lua

@@ -222,6 +222,11 @@ function _M.new(db, schema, strategy, errors)
 end
 
 
+function DAO:truncate()
+  return self.strategy:truncate()
+end
+
+
 function DAO:select(primary_key)
   if type(primary_key) ~= "table" then
     error("primary_key must be a table", 2)

kong/db/init.lua

@@ -158,8 +158,18 @@ function DB:reset()
 end
 
 
-function DB:truncate()
-  local ok, err = self.connector:truncate()
+function DB:truncate(table_name)
+  if table_name ~= nil and type(table_name) ~= "string" then
+    error("table_name must be a string", 2)
+  end
+  local ok, err
+
+  if table_name then
+    ok, err = self.connector:truncate_table(table_name)
+  else
+    ok, err = self.connector:truncate()
+  end
+
   if not ok then
     return nil, prefix_err(self, err)
   end

kong/db/strategies/cassandra/connector.lua

@@ -301,4 +301,28 @@ function CassandraConnector:truncate()
 end
 
 
+function CassandraConnector:truncate_table(table_name)
+  local ok, err = self:connect()
+  if not ok then
+    return nil, err
+  end
+
+  local cql = string.format("TRUNCATE TABLE %s.%s",
+                            self.keyspace, table_name)
+
+  local ok, err = self:query(cql)
+  if not ok then
+    self:setkeepalive()
+    return nil, err
+  end
+
+  ok, err = self:setkeepalive()
+  if not ok then
+    return nil, err
+  end
+
+  return true
+end
+
+
 return CassandraConnector

kong/db/strategies/cassandra/init.lua

@@ -986,4 +986,9 @@ function _mt:delete_by_field(field_name, field_value)
 end
 
 
+function _mt:truncate()
+  return self.connector:truncate_table(self.schema.name)
+end
+
+
 return _M

kong/db/strategies/postgres/connector.lua

@@ -313,6 +313,20 @@ function _mt:truncate()
 end
 
 
+function _mt:truncate_table(table_name)
+  local truncate_statement = {
+    "TRUNCATE TABLE ", table_name, " RESTART IDENTITY CASCADE;"
+  }
+
+  local ok, err = self:query(truncate_statement)
+  if not ok then
+    return nil, err
+  end
+
+  return true
+end
+
+
 local _M = {}
 
 

kong/db/strategies/postgres/init.lua

@@ -618,7 +618,7 @@ end
 
 
 function _mt:truncate()
-  local res, err = execute(self, "drop")
+  local res, err = execute(self, "truncate")
   if not res then
     return toerror(self, err)
   end
@@ -1276,7 +1276,7 @@ function _M.new(connector, schema, errors)
   }
 
   local truncate_statement = concat {
-    "TRUNCATE ", table_name_escaped, ";"
+    "TRUNCATE TABLE ", table_name_escaped, " RESTART IDENTITY CASCADE;"
   }
 
   local drop_statement

spec-old-api/02-integration/03-dao/04-constraints_spec.lua

@@ -22,10 +22,6 @@ for _, strategy in helpers.each_strategy() do
       bp, db, dao = helpers.get_db_utils(strategy)
       apis = dao.apis
       plugins = dao.plugins
-      assert(dao:run_migrations())
-
-      dao:truncate_tables()
-      assert(db:truncate())
     end)
     before_each(function()
       plugin_fixture = utils.shallow_copy(plugin_tbl)
@@ -34,8 +30,9 @@ for _, strategy in helpers.each_strategy() do
       api_fixture = api
     end)
     after_each(function()
-      dao:truncate_tables()
-      assert(db:truncate())
+      dao:truncate_table("apis")
+      dao:truncate_table("plugins")
+      assert(db:truncate("consumers"))
     end)
 
     -- Check behavior just in case
@@ -177,8 +174,9 @@ for _, strategy in helpers.each_strategy() do
         assert.falsy(err)
       end)
       after_each(function()
-        dao:truncate_tables()
-        assert(db:truncate())
+        dao:truncate_table("apis")
+        dao:truncate_table("plugins")
+        assert(db:truncate("consumers"))
       end)
 
       it("delete", function()

spec-old-api/02-integration/03-dao/05-use_cases_spec.lua

@@ -5,15 +5,15 @@ local helpers = require "spec.helpers"
 
 for _, strategy in helpers.each_strategy() do
   describe("Real use-cases with DB: #" .. strategy, function()
-    local dao
-    local bp
+    local bp, db, dao
     setup(function()
-      local _
-      bp, _, dao = helpers.get_db_utils(strategy)
+      bp, db, dao = helpers.get_db_utils(strategy)
     end)
 
     before_each(function()
-      dao:truncate_tables()
+      dao:truncate_table("apis")
+      dao:truncate_table("plugins")
+      db:truncate("consumers")
     end)
 
     it("retrieves plugins for plugins_iterator", function()

spec-old-api/02-integration/04-admin_api/02-apis_routes_spec.lua

@@ -3,8 +3,6 @@ local cjson = require "cjson"
 local utils = require "kong.tools.utils"
 
 local dao_helpers = require "spec.02-integration.03-dao.helpers"
-local DAOFactory = require "kong.dao.factory"
-local DB         = require "kong.db"
 
 local function it_content_types(title, fn)
   local test_form_encoded = fn("application/x-www-form-urlencoded")
@@ -16,18 +14,10 @@ end
 dao_helpers.for_each_dao(function(kong_config)
 describe("Admin API #" .. kong_config.database, function()
   local client
-  local dao
-  local db
+  local dao, _
 
   setup(function()
-    db = assert(DB.new(kong_config))
-    assert(db:init_connector())
-
-    dao = assert(DAOFactory.new(kong_config, db))
-    assert(dao:run_migrations())
-
-    dao:truncate_tables()
-    db:truncate()
+    _, _, dao = helpers.get_db_utils(kong_config.database)
 
     assert(helpers.start_kong{
       database = kong_config.database
@@ -40,7 +30,8 @@ describe("Admin API #" .. kong_config.database, function()
   describe("/apis", function()
     describe("POST", function()
       before_each(function()
-        dao:truncate_tables()
+        dao:truncate_table("apis")
+        dao:truncate_table("plugins")
         client = assert(helpers.admin_client())
       end)
       after_each(function()
@@ -175,7 +166,8 @@ describe("Admin API #" .. kong_config.database, function()
 
     describe("PUT", function()
       before_each(function()
-        dao:truncate_tables()
+        dao:truncate_table("apis")
+        dao:truncate_table("plugins")
         client = assert(helpers.admin_client())
       end)
       after_each(function()
@@ -352,7 +344,8 @@ describe("Admin API #" .. kong_config.database, function()
 
     describe("GET", function()
       setup(function()
-        dao:truncate_tables()
+        dao:truncate_table("apis")
+        dao:truncate_table("plugins")
 
         for i = 1, 10 do
           assert(dao.apis:insert {
@@ -363,7 +356,8 @@ describe("Admin API #" .. kong_config.database, function()
         end
       end)
       teardown(function()
-        dao:truncate_tables()
+        dao:truncate_table("apis")
+        dao:truncate_table("plugins")
       end)
       before_each(function()
         client = assert(helpers.admin_client())
@@ -435,7 +429,8 @@ describe("Admin API #" .. kong_config.database, function()
 
       describe("empty results", function()
         setup(function()
-          dao:truncate_tables()
+          dao:truncate_table("apis")
+          dao:truncate_table("plugins")
         end)
 
         it("data property is an empty array", function()
@@ -452,7 +447,8 @@ describe("Admin API #" .. kong_config.database, function()
 
     describe("DELETE", function()
       before_each(function()
-        dao:truncate_tables()
+        dao:truncate_table("apis")
+        dao:truncate_table("plugins")
         client = assert(helpers.admin_client())
       end)
       after_each(function()
@@ -479,7 +475,8 @@ describe("Admin API #" .. kong_config.database, function()
   describe("/apis/{api}", function()
     local api
     setup(function()
-      dao:truncate_tables()
+      dao:truncate_table("apis")
+      dao:truncate_table("plugins")
     end)
     before_each(function()
       api = assert(dao.apis:insert {
@@ -489,7 +486,8 @@ describe("Admin API #" .. kong_config.database, function()
       })
     end)
     after_each(function()
-      dao:truncate_tables()
+      dao:truncate_table("apis")
+      dao:truncate_table("plugins")
     end)
 
     describe("GET", function()
@@ -739,7 +737,8 @@ describe("Admin API #" .. kong_config.database, function()
   describe("/apis/{api}/plugins", function()
     local api
     setup(function()
-      dao:truncate_tables()
+      dao:truncate_table("apis")
+      dao:truncate_table("plugins")
 
       api = assert(dao.apis:insert {
         name = "my-api",

spec-old-api/02-integration/04-admin_api/08-targets_routes_spec.lua

@@ -21,7 +21,8 @@ describe("Admin API", function()
     assert(helpers.start_kong())
     client = assert(helpers.admin_client())
 
-    helpers.dao:truncate_tables()
+    helpers.dao:truncate_table("upstreams")
+    helpers.dao:truncate_table("targets")
 
     upstream = assert(helpers.dao.upstreams:insert {
       name = upstream_name,

spec-old-api/02-integration/05-proxy/01-router_spec.lua

@@ -6,7 +6,7 @@ local function insert_apis(arr)
     return error("expected arg #1 to be a table", 2)
   end
 
-  helpers.dao:truncate_tables()
+  helpers.dao:truncate_table("apis")
 
   for i = 1, #arr do
     assert(helpers.dao.apis:insert(arr[i]))
@@ -29,7 +29,9 @@ describe("Router", function()
   describe("no APIs match", function()
 
     setup(function()
-      helpers.dao:truncate_tables()
+      helpers.dao:truncate_table("apis")
+      helpers.db:truncate("routes")
+      helpers.db:truncate("services")
       helpers.dao:run_migrations()
       assert(helpers.start_kong())
     end)
@@ -180,7 +182,7 @@ describe("Router", function()
 
   describe("URI regexes order of evaluation", function()
     setup(function()
-      helpers.dao:truncate_tables()
+      helpers.dao:truncate_table("apis")
 
       assert(helpers.dao.apis:insert {
         name = "api-1",
@@ -714,7 +716,7 @@ describe("Router", function()
     }
 
     setup(function()
-      helpers.dao:truncate_tables()
+      helpers.dao:truncate_table("apis")
 
       for i, args in ipairs(checks) do
         assert(helpers.dao.apis:insert {

spec-old-api/02-integration/05-proxy/02-upstream_headers_spec.lua

@@ -7,7 +7,7 @@ local function insert_apis(arr)
     return error("expected arg #1 to be a table", 2)
   end
 
-  helpers.dao:truncate_tables()
+  helpers.dao:truncate_table("apis")
 
   for i = 1, #arr do
     assert(helpers.dao.apis:insert(arr[i]))

spec-old-api/02-integration/05-proxy/03-plugins_triggering_spec.lua

@@ -174,7 +174,8 @@ describe("Plugins triggering", function()
       end
 
       helpers.stop_kong()
-      helpers.dao:truncate_tables()
+      helpers.dao:truncate_table("apis")
+      helpers.dao:truncate_table("plugins")
 
 
       do
@@ -389,7 +390,8 @@ describe("Plugins triggering", function()
 
       helpers.stop_kong()
 
-      helpers.dao:truncate_tables()
+      helpers.dao:truncate_table("apis")
+      helpers.dao:truncate_table("plugins")
 
       local api      = assert(helpers.dao.apis:insert {
         name         = "example",

spec-old-api/02-integration/05-proxy/11-error_default_type_spec.lua

@@ -10,7 +10,7 @@ describe("Proxy errors Content-Type", function()
   local client
 
   setup(function()
-    helpers.dao:truncate_tables()
+    helpers.dao:truncate_table("apis")
 
     assert(helpers.dao.apis:insert {
       name                     = "api-1",