feat: #68 migrate keyspace if it doesn't exist.

Instead of doing this in the bash script, we do it in main.lua
ini_by_lua since the error handling from bin/kong is already handled.

We only run migrations if we detect than they wer enever ran before. We
won't automatically run any new migration because the process shouldn't
be transparent, users should know about it and backup their data if they
want to.

bin/kong

@@ -55,7 +55,7 @@ function print_start_error {
 ##############
 
 function show_help {
-  printf "Usage: kong [OPTION]... {start|stop|restart|migrate}\n
+  printf "Usage: kong [OPTION]... {start|stop|restart}\n
 \t-c    specify the path to a custom Kong configuration file
 \t      default is: '$KONG_HOME/kong.yml'
 \t-v    output version informations and exit
@@ -65,7 +65,6 @@ function show_help {
 \tstop       stop a running Kong
 \trestart    restart Kong
 \t           it is equivalent to executing 'stop' and 'start' in succession
-\tmigrate    performs a database migration, execute this operation carefully
 \tversion    output version informations and exit
 \n"
 }
@@ -107,15 +106,6 @@ function start {
   fi
 }
 
-function migrate {
-  $KONG_HOME/scripts/db.lua -c $KONG_CONF migrate
-  if [ $? -eq 0 ]; then
-    exit 0
-  else
-    exit 1
-  fi
-}
-
 function stop {
   printf "Stopping Kong"
 
@@ -173,9 +163,6 @@ case "$@" in
   restart)
       restart
       ;;
-  migrate)
-      migrate
-      ;;
   version)
       show_version
       ;;

src/kong/dao/cassandra/base_dao.lua

@@ -34,7 +34,6 @@ end
 -- Since this method only accepts an ordered list, we build this list from
 -- the `params` property of all prepared statement, taking into account special
 -- cassandra values (uuid, timestamps, NULL)
---
 -- @param {table} schema A schema with type properties to encode specific values
 -- @param {table} t Values to bind to a statement
 -- @param {table} parameters An ordered list of parameters

src/kong/dao/cassandra/factory.lua

@@ -58,16 +58,15 @@ end
 
 -- Prepare all statements in collection._queries and put them in collection._statements.
 -- Should be called with only a collection and will recursively call itself for nested statements.
---
 -- @param collection A collection with a ._queries property
-local function prepare(collection, queries, statements)
+local function prepare_collection(collection, queries, statements)
   if not queries then queries = collection._queries end
   if not statements then statements = collection._statements end
 
   for stmt_name, query in pairs(queries) do
     if type(query) == "table" and query.query == nil then
       collection._statements[stmt_name] = {}
-      prepare(collection, query, collection._statements[stmt_name])
+      prepare_collection(collection, query, collection._statements[stmt_name])
     else
       local q = stringy.strip(query.query)
       q = string.format(q, "")
@@ -88,7 +87,7 @@ function CassandraFactory:prepare()
                                 self.plugins,
                                 self.accounts,
                                 self.applications }) do
-    local err = prepare(collection)
+    local err = prepare_collection(collection)
     if err then
       return err
     end
@@ -97,7 +96,6 @@ end
 
 -- Execute a string of queries separated by ;
 -- Useful for huge DDL operations such as migrations
---
 -- @param {string} queries Semicolon separated string of queries
 -- @param {boolean} no_keyspace Won't set the keyspace if true
 -- @return {string} error if any
@@ -180,15 +178,17 @@ end
 -- @return A list of previously executed migration (as strings)
 -- @return error if any
 function CassandraFactory:get_migrations()
-  local keyspace, err = self:execute("SELECT * FROM schema_keyspaces WHERE keyspace_name = ?", { self._properties.keyspace }, "system")
+  local rows, err
+
+  rows, err = self:execute("SELECT * FROM schema_keyspaces WHERE keyspace_name = ?", { self._properties.keyspace }, "system")
   if err then
     return nil, err
-  elseif #keyspace == 0 then
+  elseif #rows == 0 then
     -- keyspace is not yet created, this is the first migration
     return nil
   end
 
-  local rows, err = self:execute("SELECT migrations FROM schema_migrations WHERE id = ?", { MIGRATION_IDENTIFIER })
+  rows, err = self:execute("SELECT migrations FROM schema_migrations WHERE id = ?", { MIGRATION_IDENTIFIER })
   if err then
     return nil, err
   elseif rows and #rows > 0 then

src/kong/tools/migrations.lua

@@ -136,7 +136,7 @@ function Migrations:rollback(callback)
   if not migration_to_rollback.init then
     local _, err = self.dao:delete_migration(migration_to_rollback.name)
     if err then
-      callback(migration_to_rollback, "Cannot delete migration "..migration_to_rollback.name..": "..err) -- avoid a luacheck warning if calling cb directly here
+      callback(migration_to_rollback, "Cannot delete migration "..migration_to_rollback.name..": "..err)
       return
     end
   end

src/main.lua

@@ -62,8 +62,6 @@ local function load_plugin_conf(api_id, application_id, plugin_name)
 end
 
 local function init_plugins()
-  -- Initializing plugins
-
   plugins_available = configuration.plugins_available and configuration.plugins_available or {}
 
   print("Discovering used plugins. Please wait..")
@@ -126,10 +124,25 @@ function _M.init()
   -- Loading configuration
   configuration, dao = utils.load_configuration_and_dao(os.getenv("KONG_CONF"))
 
+  -- Detect if keyspace is set
+  local keyspace, err = dao:get_migrations()
+  if err then
+    error(err)
+  elseif keyspace == nil then
+    -- No previous migrations, it should be safe to run them
+    print("Database not initialized. Running migrations...")
+    local migrations = require("kong.tools.migrations")(dao)
+    migrations:migrate(function(migration, err)
+      if err then
+        error(err)
+      end
+    end)
+  end
+
   -- Initializing DAO
   local err = dao:prepare()
   if err then
-    error("Cannot prepare Cassandra statements: "..err.message)
+    error("Cannot prepare statements: "..err.message)
   end
 
   -- Initializing plugins