diff --git a/changelogs/unreleased/gh-9078-roles.md b/changelogs/unreleased/gh-9078-roles.md
new file mode 100644
index 0000000000000000000000000000000000000000..00ae8694fbe5d642b33bc089c5c6c60a7e401384
--- /dev/null
+++ b/changelogs/unreleased/gh-9078-roles.md
@@ -0,0 +1,4 @@
+## feature/config
+
+* Introduced the initial support for roles - programs that run when
+ a configuration is loaded or reloaded (gh-9078).
diff --git a/src/box/CMakeLists.txt b/src/box/CMakeLists.txt
index e108f3b1f434d01d94bdf2cd1540e5ca872251ca..616d5aef395dd2ab51f2b0cb66765b3ba63ec685 100644
--- a/src/box/CMakeLists.txt
+++ b/src/box/CMakeLists.txt
@@ -44,6 +44,7 @@ lua_source(lua_sources lua/config/applier/console.lua config_applier_console
lua_source(lua_sources lua/config/applier/credentials.lua config_applier_credentials_lua)
lua_source(lua_sources lua/config/applier/fiber.lua config_applier_fiber_lua)
lua_source(lua_sources lua/config/applier/mkdir.lua config_applier_mkdir_lua)
+lua_source(lua_sources lua/config/applier/roles.lua config_applier_roles_lua)
lua_source(lua_sources lua/config/applier/sharding.lua config_applier_sharding_lua)
lua_source(lua_sources lua/config/cluster_config.lua config_cluster_config_lua)
lua_source(lua_sources lua/config/configdata.lua config_configdata_lua)
diff --git a/src/box/lua/config/applier/roles.lua b/src/box/lua/config/applier/roles.lua
new file mode 100644
index 0000000000000000000000000000000000000000..9e343794c5dba82d8a537fe33483a6dc2d193e3b
--- /dev/null
+++ b/src/box/lua/config/applier/roles.lua
@@ -0,0 +1,87 @@
+local log = require('internal.config.utils.log')
+
+local last_loaded = {}
+local last_loaded_names_ordered = {}
+
+local function stop_roles(roles_to_skip)
+ for id = #last_loaded_names_ordered, 1, -1 do
+ local role_name = last_loaded_names_ordered[id]
+ if roles_to_skip == nil or roles_to_skip[role_name] == nil then
+ log.verbose('roles.apply: stop role ' .. role_name)
+ local ok, err = pcall(last_loaded[role_name].stop)
+ if not ok then
+ error(('Error stopping role %s: %s'):format(role_name, err), 0)
+ end
+ end
+ end
+end
+
+local function apply(config)
+ local configdata = config._configdata
+ local role_names = configdata:get('roles', {use_default = true})
+ if role_names == nil or next(role_names) == nil then
+ stop_roles()
+ return
+ end
+
+ -- Remove duplicates.
+ local roles = {}
+ local roles_ordered = {}
+ for _, role_name in pairs(role_names) do
+ if roles[role_name] == nil then
+ table.insert(roles_ordered, role_name)
+ end
+ roles[role_name] = true
+ end
+
+ -- Stop removed roles.
+ stop_roles(roles)
+
+ -- Run roles.
+ local roles_cfg = configdata:get('roles_cfg', {use_default = true}) or {}
+ local loaded = {}
+ local loaded_names_ordered = {}
+
+ -- Load roles.
+ for _, role_name in ipairs(roles_ordered) do
+ local role = last_loaded[role_name]
+ if not role then
+ log.verbose('roles.apply: load role ' .. role_name)
+ role = require(role_name)
+ local funcs = {'validate', 'apply', 'stop'}
+ for _, func_name in pairs(funcs) do
+ if type(role[func_name]) ~= 'function' then
+ local err = 'Role %s does not contain function %s'
+ error(err:format(role_name, func_name), 0)
+ end
+ end
+ end
+ loaded[role_name] = role
+ table.insert(loaded_names_ordered, role_name)
+ end
+
+ -- Validate configs for all roles.
+ for _, role_name in ipairs(roles_ordered) do
+ local ok, err = pcall(loaded[role_name].validate, roles_cfg[role_name])
+ if not ok then
+ error(('Wrong config for role %s: %s'):format(role_name, err), 0)
+ end
+ end
+
+ -- Apply configs for all roles.
+ for _, role_name in ipairs(roles_ordered) do
+ log.verbose('roles.apply: apply config for role ' .. role_name)
+ local ok, err = pcall(loaded[role_name].apply, roles_cfg[role_name])
+ if not ok then
+ error(('Error applying role %s: %s'):format(role_name, err), 0)
+ end
+ end
+
+ last_loaded = loaded
+ last_loaded_names_ordered = loaded_names_ordered
+end
+
+return {
+ name = 'roles',
+ apply = apply,
+}
diff --git a/src/box/lua/config/init.lua b/src/box/lua/config/init.lua
index 3f45bf11a1a7c9f70557a4837a91d216b64f765b..2bd0cd5102296c77d52630f14abe4c93f9312a63 100644
--- a/src/box/lua/config/init.lua
+++ b/src/box/lua/config/init.lua
@@ -150,6 +150,7 @@ function methods._initialize(self)
self:_register_applier(require('internal.config.applier.console'))
self:_register_applier(require('internal.config.applier.fiber'))
self:_register_applier(require('internal.config.applier.sharding'))
+ self:_register_applier(require('internal.config.applier.roles'))
self:_register_applier(require('internal.config.applier.app'))
if extras ~= nil then
diff --git a/src/box/lua/config/instance_config.lua b/src/box/lua/config/instance_config.lua
index e3881119ce2318f50cf1cf687bff666afb526006..af259943b49117a492a25a5be263079e7908e458 100644
--- a/src/box/lua/config/instance_config.lua
+++ b/src/box/lua/config/instance_config.lua
@@ -1802,6 +1802,13 @@ return schema.new('instance_config', schema.record({
"compatibility",
}),
})),
+ roles_cfg = schema.map({
+ key = schema.scalar({type = 'string'}),
+ value = schema.scalar({type = 'any'}),
+ }),
+ roles = schema.array({
+ items = schema.scalar({type = 'string'})
+ }),
}, {
-- This kind of validation cannot be implemented as the
-- 'validate' annotation of a particular schema node. There
diff --git a/src/box/lua/init.c b/src/box/lua/init.c
index feab7f57fdfa9bdd94fcad42fc7b831f1da69193..36d7e794aac3f810c8628aaf702708a3277c72e7 100644
--- a/src/box/lua/init.c
+++ b/src/box/lua/init.c
@@ -144,6 +144,7 @@ extern char session_lua[],
config_applier_credentials_lua[],
config_applier_fiber_lua[],
config_applier_mkdir_lua[],
+ config_applier_roles_lua[],
config_applier_sharding_lua[],
config_cluster_config_lua[],
config_configdata_lua[],
@@ -387,6 +388,10 @@ static const char *lua_sources[] = {
"internal.config.applier.sharding",
config_applier_sharding_lua,
+ "config/applier/roles",
+ "internal.config.applier.roles",
+ config_applier_roles_lua,
+
"config/init",
"config",
config_init_lua,
diff --git a/test/config-luatest/helpers.lua b/test/config-luatest/helpers.lua
index f998f31db6d58badfc5391d4cd6166bc4e3e1522..f068024b7d343ec73991a7c67d9c88d00b121396 100644
--- a/test/config-luatest/helpers.lua
+++ b/test/config-luatest/helpers.lua
@@ -88,6 +88,7 @@ local simple_config = {
local function prepare_case(g, opts)
local dir = opts.dir
+ local roles = opts.roles
local script = opts.script
local options = opts.options
@@ -95,6 +96,12 @@ local function prepare_case(g, opts)
dir = treegen.prepare_directory(g, {}, {})
end
+ if roles ~= nil and next(roles) ~= nil then
+ for name, body in pairs(roles) do
+ treegen.write_script(dir, name .. '.lua', body)
+ end
+ end
+
if script ~= nil then
treegen.write_script(dir, 'main.lua', script)
end
@@ -135,6 +142,10 @@ end
-- Start a server with the given script and the given
-- configuration, run a verification function on it.
--
+-- * opts.roles
+--
+-- Role codes for writing into corresponding files.
+--
-- * opts.script
--
-- Code write into the main.lua file.
@@ -164,6 +175,7 @@ end
-- Start tarantool process with the given script/config and check
-- the error.
--
+-- * opts.roles
-- * opts.script
-- * opts.options
--
@@ -185,12 +197,17 @@ end
-- Start a server, write a new script/config, reload, run a
-- verification function.
--
+-- * opts.roles
-- * opts.script
-- * opts.options
-- * opts.verify
--
-- Same as in success_case().
--
+-- * opts.roles_2
+--
+-- A new list of roles to prepare before config:reload().
+--
-- * opts.script_2
--
-- A new script to write into the main.lua file before
@@ -205,6 +222,7 @@ end
--
-- Verify test invariants after config:reload().
local function reload_success_case(g, opts)
+ local roles_2 = opts.roles_2
local script_2 = opts.script_2
local options = assert(opts.options)
local verify_2 = assert(opts.verify_2)
@@ -214,6 +232,7 @@ local function reload_success_case(g, opts)
prepare_case(g, {
dir = prepared.dir,
+ roles = roles_2,
script = script_2,
options = options_2,
})
@@ -227,31 +246,44 @@ end
-- Start a server, write a new script/config, reload, run a
-- verification function.
--
+-- * opts.roles
-- * opts.script
-- * opts.options
-- * opts.verify
--
-- Same as in success_case().
--
+-- * opts.roles_2
+--
+-- A new list of roles to prepare before config:reload().
+--
-- * opts.script_2
--
-- A new script to write into the main.lua file before
-- config:reload().
--
+-- * opts.options_2
+--
+-- A new config to use for the config:reload(). It is optional,
+-- if not provided opts.options is used instead.
+--
-- * opts.exp_err
--
-- An error that config:reload() must raise.
local function reload_failure_case(g, opts)
- local script_2 = assert(opts.script_2)
+ local script_2 = opts.script_2
+ local roles_2 = opts.roles_2
local options = assert(opts.options)
+ local options_2 = opts.options_2 or options
local exp_err = assert(opts.exp_err)
local prepared = success_case(g, opts)
prepare_case(g, {
dir = prepared.dir,
+ roles = roles_2,
script = script_2,
- options = options,
+ options = options_2,
})
t.assert_error_msg_equals(exp_err, g.server.exec, g.server, function()
local config = require('config')
diff --git a/test/config-luatest/roles_test.lua b/test/config-luatest/roles_test.lua
new file mode 100644
index 0000000000000000000000000000000000000000..c637af8cea8f02c18faa9408925adb84ea8d10bc
--- /dev/null
+++ b/test/config-luatest/roles_test.lua
@@ -0,0 +1,355 @@
+local t = require('luatest')
+local helpers = require('test.config-luatest.helpers')
+
+local g = helpers.group()
+
+-- Make sure the role is properly loaded.
+g.test_single_role_success = function(g)
+ local one = [[
+ local function apply(cfg)
+ _G.bar = cfg
+ end
+
+ _G.foo = 42
+ _G.bar = nil
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+ local verify = function()
+ local config = require('config')
+ t.assert_equals(_G.foo, 42)
+ local roles_cfg = config:get('roles_cfg')
+ t.assert_equals(roles_cfg['one'], 12345)
+ t.assert_equals(roles_cfg['one'], _G.bar)
+ end
+
+ helpers.success_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 12345},
+ ['roles'] = {'one'}
+ },
+ verify = verify,
+ })
+end
+
+-- Make sure the role is loaded only once during each run.
+g.test_role_repeat_success = function(g)
+ local one = [[
+ local function apply(cfg)
+ _G.foo = _G.foo * cfg
+ end
+
+ _G.foo = 42
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+ local verify = function()
+ local config = require('config')
+ local roles_cfg = config:get('roles_cfg')
+ t.assert_equals(roles_cfg['one'], 3)
+ t.assert_equals(_G.foo, 42 * 3)
+ end
+
+ helpers.success_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 3},
+ ['roles'] = {'one', 'one', 'one', 'one', 'one', 'one', 'one'}
+ },
+ verify = verify,
+ })
+end
+
+-- Make sure all roles are loaded correctly and in correct order.
+g.test_multiple_role_success = function(g)
+ local one = [[
+ local function apply(cfg)
+ _G.foo = tonumber(cfg)
+ end
+
+ _G.foo = nil
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+
+ local two = [[
+ local function apply(cfg)
+ _G.foo = _G.foo + tonumber(cfg)
+ end
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+
+ local three = [[
+ local function apply(cfg)
+ _G.foo = foo / tonumber(cfg)
+ end
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+
+ local verify = function()
+ local config = require('config')
+ t.assert_equals(config:get('roles'), {'one', 'two', 'three'})
+ local roles_cfg = config:get('roles_cfg')
+ local one = roles_cfg['one']
+ local two = roles_cfg['two']
+ local three = roles_cfg['three']
+ t.assert_equals(one, 42)
+ t.assert_equals(two, '24')
+ t.assert_equals(three, 3)
+ t.assert_equals(_G.foo, 22)
+ end
+
+ helpers.success_case(g, {
+ roles = {one = one, two = two, three = three},
+ options = {
+ ['roles_cfg'] = {one = 42, two = '24', three = 3},
+ ['roles'] = {'one', 'two', 'three'}
+ },
+ verify = verify,
+ })
+end
+
+-- Make sure the roles call apply() during a reload.
+g.test_role_reload_success = function(g)
+ local one = [[
+ local function apply(cfg)
+ _G.foo = _G.foo * cfg
+ end
+
+ _G.foo = 42
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+
+ local verify = function()
+ local config = require('config')
+ local roles_cfg = config:get('roles_cfg')
+ t.assert_equals(roles_cfg['one'], 2)
+ t.assert_equals(_G.foo, 42 * 2)
+ end
+
+ local verify_2 = function()
+ local config = require('config')
+ local roles_cfg = config:get('roles_cfg')
+ t.assert_equals(roles_cfg['one'], 3)
+ t.assert_equals(_G.foo, 42 * 2 * 3)
+ end
+
+ helpers.reload_success_case(g, {
+ roles = {one = one},
+ roles_2 = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 2},
+ ['roles'] = {'one'}
+ },
+ options_2 = {
+ ['roles_cfg'] = {one = 3},
+ ['roles'] = {'one'}
+ },
+ verify = verify,
+ verify_2 = verify_2,
+ })
+end
+
+-- Make sure the roles are stopped after reload if they were removed from the
+-- configuration.
+g.test_role_stop_success = function(g)
+ local one = [[
+ local function apply(cfg)
+ _G.foo = _G.foo * cfg
+ end
+
+ local function stop()
+ _G.foo = _G.foo - 100
+ end
+
+ _G.foo = 42
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = stop,
+ }
+ ]]
+
+ local verify = function()
+ local config = require('config')
+ t.assert_equals(config:get('roles'), {'one'})
+ local roles_cfg = config:get('roles_cfg')
+ t.assert_equals(roles_cfg['one'], 2)
+ t.assert_equals(_G.foo, 42 * 2)
+ end
+
+ local verify_2 = function()
+ local config = require('config')
+ t.assert_equals(config:get('roles'), nil)
+ local roles_cfg = config:get('roles_cfg')
+ t.assert_equals(roles_cfg['one'], 1)
+ t.assert_equals(_G.foo, 42 * 2 - 100)
+ end
+
+ helpers.reload_success_case(g, {
+ roles = {one = one},
+ roles_2 = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 2},
+ ['roles'] = {'one'}
+ },
+ options_2 = {
+ ['roles_cfg'] = {one = 1},
+ },
+ verify = verify,
+ verify_2 = verify_2,
+ })
+end
+
+-- Ensure that errors during config validation are handled correctly.
+g.test_role_validate_error = function(g)
+ local one = [[
+ local function validate(cfg)
+ error('something wrong', 0)
+ end
+
+ return {
+ validate = validate,
+ apply = function() end,
+ stop = function() end,
+ }
+ ]]
+
+ helpers.failure_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 1},
+ ['roles'] = {'one'}
+ },
+ exp_err = 'Wrong config for role one: something wrong'
+ })
+end
+
+-- Ensure that errors during role application are handled correctly.
+g.test_role_apply_error = function(g)
+ local one = [[
+ local function apply(cfg)
+ error('something wrong', 0)
+ end
+
+ return {
+ validate = function() end,
+ apply = apply,
+ stop = function() end,
+ }
+ ]]
+
+ helpers.failure_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 1},
+ ['roles'] = {'one'}
+ },
+ exp_err = 'Error applying role one: something wrong'
+ })
+end
+
+-- Make sure an error is raised if not all methods are present.
+g.test_role_no_method_error = function(g)
+ local one = [[
+ return {
+ apply = function() end,
+ stop = function() end,
+ }
+ ]]
+ helpers.failure_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 1},
+ ['roles'] = {'one'}
+ },
+ exp_err = 'Role one does not contain function validate'
+ })
+
+ one = [[
+ return {
+ validate = function() end,
+ stop = function() end,
+ }
+ ]]
+ helpers.failure_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 1},
+ ['roles'] = {'one'}
+ },
+ exp_err = 'Role one does not contain function apply'
+ })
+
+ one = [[
+ return {
+ validate = function() end,
+ apply = function() end,
+ }
+ ]]
+ helpers.failure_case(g, {
+ roles = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 1},
+ ['roles'] = {'one'}
+ },
+ exp_err = 'Role one does not contain function stop'
+ })
+end
+
+-- Ensure that errors during role stopping are handled correctly.
+--
+-- Also verify that the error is raised by config:reload() and the same error
+-- appears in the alerts.
+g.test_role_reload_error = function(g)
+ local one = [[
+ return {
+ validate = function() end,
+ apply = function() end,
+ stop = function() error('Wrongly stopped', 0) end,
+ }
+ ]]
+
+ helpers.reload_failure_case(g, {
+ roles = {one = one},
+ roles_2 = {one = one},
+ options = {
+ ['roles_cfg'] = {one = 1},
+ ['roles'] = {'one'}
+ },
+ options_2 = {
+ ['roles_cfg'] = {one = 1},
+ },
+ verify = function() end,
+ exp_err = 'Error stopping role one: Wrongly stopped'
+ })
+end