fix(migration): migrate queue parameters

In #10840, some queue parameter types were changed
so that values were more restricted than in the original schema.  This commit adds
a data migration so that any values that would not be valid according to the new
schema are updated.  Testing this migration is done with an integration test rather
than using the upgrade tests logic because the latter does not currently support
testing upgrades in a way that'd be required for this change.

kong/db/migrations/core/020_330_to_340.lua

@@ -0,0 +1,6 @@
+local queue_parameter_migration_340 = require('kong.db.migrations.core.queue_parameter_migration_340')
+return {
+  postgres = {
+    up = queue_parameter_migration_340,
+  }
+}

kong/db/migrations/core/init.lua

@@ -17,4 +17,5 @@ return {
   "017_300_to_310",
   "018_310_to_320",
   "019_320_to_330",
+  "020_330_to_340",
 }

kong/db/migrations/core/queue_parameter_migration_340.lua

@@ -0,0 +1,23 @@
+-- This data migration updates queue parameters so that they conform to the changes made in https://github.com/Kong/kong/pull/10840
+-- The migration lives in a separate file so that it can be tested easily
+return [[
+update plugins
+set config = jsonb_set(config, '{queue, max_batch_size}', to_jsonb(round((config->'queue'->>'max_batch_size')::numeric)))
+where config->'queue'->>'max_batch_size' is not null;
+
+update plugins
+set config = jsonb_set(config, '{queue, max_entries}', to_jsonb(round((config->'queue'->>'max_entries')::numeric)))
+where config->'queue'->>'max_entries' is not null;
+
+update plugins
+set config = jsonb_set(config, '{queue, max_bytes}', to_jsonb(round((config->'queue'->>'max_bytes')::numeric)))
+where config->'queue'->>'max_bytes' is not null;
+
+update plugins
+set config = jsonb_set(config, '{queue, initial_retry_delay}', to_jsonb(least(greatest((config->'queue'->>'initial_retry_delay')::numeric, 0.001), 1000000)))
+where config->'queue'->>'initial_retry_delay' is not null;
+
+update plugins
+set config = jsonb_set(config, '{queue, max_retry_delay}', to_jsonb(least(greatest((config->'queue'->>'max_retry_delay')::numeric, 0.001), 1000000)))
+where config->'queue'->>'max_retry_delay' is not null;
+]]

spec/03-plugins/02-queue_parameter_migration_340_spec.lua

@@ -0,0 +1,82 @@
+local cjson = require "cjson"
+local tablex = require "pl.tablex"
+local helpers = require "spec.helpers"
+local Schema = require "kong.db.schema"
+local queue_schema = Schema.new(require "kong.tools.queue_schema")
+local queue_parameter_migration_340 = require "kong.db.migrations.core.queue_parameter_migration_340"
+
+describe("Kong Gateway 3.4 queue parameter migration", function()
+  local db
+
+  local function load_queue_config()
+    local rows, err = db.connector:query([[SELECT config->>'queue' AS queue_config FROM plugins]])
+    assert(rows, "SQL query for queue config failed: " .. (err or ""))
+    return cjson.decode(rows[1].queue_config)
+  end
+
+  local sane_queue_config
+
+  lazy_setup(function()
+    -- Create a service to make sure that our database is initialized properly.
+    local bp
+    bp, db = helpers.get_db_utils()
+
+    db:truncate()
+
+    bp.plugins:insert{
+      name = "http-log",
+      config = {
+        http_endpoint = "http://example.com",
+      }
+    }
+
+    sane_queue_config = load_queue_config()
+  end)
+
+  local function update_plugin_queue_config(queue_config)
+    local query = string.format([[
+        UPDATE plugins
+        SET config = jsonb_set(config, '{queue}', '%s'::jsonb)
+        WHERE config->'queue' IS NOT NULL]],
+      cjson.encode(queue_config))
+    local ok, err = db.connector:query(query)
+    assert(ok, "SQL query " .. query .. " failed: " .. (err or ""))
+  end
+
+  local function validate_queue_config()
+    local queue_config = load_queue_config()
+    assert(queue_schema:validate(queue_config))
+    return queue_config
+  end
+
+  local function run_migration()
+    local ok, err = db.connector:query(queue_parameter_migration_340)
+    assert(ok, "Running migration failed: " .. (err or ""))
+  end
+
+  local function test_one_parameter(key, value, migrated_value)
+    local queue_config = tablex.deepcopy(sane_queue_config)
+    queue_config[key] = value
+    update_plugin_queue_config(queue_config)
+    run_migration()
+    local migrated_queue_config = validate_queue_config()
+    assert.equals(migrated_value, migrated_queue_config[key])
+  end
+
+  it("parameters that were previously unrestricted migrated to conform to the restricions", function()
+    test_one_parameter("max_batch_size", 120, 120)
+    test_one_parameter("max_batch_size", 120.20, 120)
+    test_one_parameter("max_entries", 203, 203)
+    test_one_parameter("max_entries", 203.20, 203)
+    test_one_parameter("max_bytes", 304, 304)
+    test_one_parameter("max_bytes", 303.9, 304)
+    test_one_parameter("initial_retry_delay", -2000, 0.001)
+    test_one_parameter("initial_retry_delay", 0.001, 0.001)
+    test_one_parameter("initial_retry_delay", 1000000, 1000000)
+    test_one_parameter("initial_retry_delay", 39999999, 1000000)
+    test_one_parameter("max_retry_delay", -2000, 0.001)
+    test_one_parameter("max_retry_delay", 0.001, 0.001)
+    test_one_parameter("max_retry_delay", 1000000, 1000000)
+    test_one_parameter("max_retry_delay", 39999999, 1000000)
+  end)
+end)

spec/05-migration/db/migrations/core/020_330_to_340_spec.lua

@@ -0,0 +1,5 @@
+local uh = require "spec/upgrade_helpers"
+
+describe("database migration", function()
+  -- This is a placeholder at this point
+end)