Overhaul database package

golden/go/db/db.go

 package db
 
 import (
         "fmt"
-        "strings"
 
-        "github.com/golang/glog"
         "skia.googlesource.com/buildbot.git/go/database"
-        "skia.googlesource.com/buildbot.git/go/metadata"
 )
 
 const (
         // Key of the password for the readwrite user.
         METADATA_KEY = "readwrite"
 
         // Detfault database parameters.
         DEFAULT_DB_HOST = "173.194.104.24"
         DEFAULT_DB_PORT = "3306"
         DEFAULT_DB_NAME = "skiacorrectness"
 
         // Template to generate the MySQL database connection string.
         // And 3306 is the default port for MySQL.
         DB_CONN_TMPL = "%s:%s@tcp(%s:%s)/%s?parseTime=true"
 )
 
 // MigrationSteps returns the migration (up and down) for the database.
 func MigrationSteps() []database.MigrationStep {
         return migrationSteps
 }
 
-// GetConfig returns a DatabaseConfig instance for running in production if a
-// metadata server is available. If 'local' is true it will always
-// set the MySQL connection string to "" and thus use a local SQLite database
-// when used with database.NewVersionedDB.
-func GetConfig(mySQLConnStr string, sqlitePath string, local bool) *database.DatabaseConfig {
-        useMySQLConnStr := mySQLConnStr
-
-        // We are in the production environment, so we look up the password.
-        if !local {
-                //  First, get the password from the metadata server.
-                // See https://developers.google.com/compute/docs/metadata#custom.
-                password, err := metadata.Get(METADATA_KEY)
-                if err != nil {
-                        glog.Fatalf("Failed to find metadata. Use 'local' flag when running locally.")
-                }
-                useMySQLConnStr = fmt.Sprintf(mySQLConnStr, password)
+// DatabaseConfig returns a DatabaseConfig instance. If mySQLConnStr is
+// provided, it overrides all other settings. Otherwise, if 'local' is true
+// a config for a local MySQL database is returned. If 'local' is false, a
+// config appropriate for running in production is returned.
+func DatabaseConfig(mySQLConnStr string, local bool) (*database.DatabaseConfig, error) {
+        if mySQLConnStr != "" {
+                return database.ResolveCustomMySQLString(mySQLConnStr, migrationSteps)
         }
 
-        // If there is still a placeholder in the connection string, we
-        // set it to empty, so that the the local SQLite database kicks in.
-        if strings.Contains(useMySQLConnStr, "%s") {
-                useMySQLConnStr = ""
-        }
-
-        return &database.DatabaseConfig{
-                MySQLString:    useMySQLConnStr,
-                SQLiteFilePath: sqlitePath,
-                MigrationSteps: migrationSteps,
+        if local {
+                return database.LocalDatabaseConfig(DEFAULT_DB_NAME, migrationSteps), nil
+        } else {
+                return database.ProdDatabaseConfig(database.AddrFromHostPort(DEFAULT_DB_HOST, DEFAULT_DB_PORT), DEFAULT_DB_NAME, migrationSteps), nil
         }
 }
 
 // GetConnectionString returns a MySQL connection string with the given
 // parameters replace in the template. Only userName has to be provided.
 // If host, port or dbName are empty the default (production) values will
 // be used.
 func GetConnectionString(userName, host, port, dbName string) string {
         useHost, usePort, useDBName := host, port, dbName
         if useHost == "" {
@@ skipping 21 matching lines @@
                         `CREATE TABLE expectations (
                                 id            INT        NOT NULL AUTO_INCREMENT PRIMARY KEY,
                                 userid        TEXT       NOT NULL,
                                 ts            BIGINT     NOT NULL,
                                 expectations  MEDIUMTEXT NOT NULL
                         )`,
                 },
                 MySQLDown: []string{
                         `DROP TABLE expectations`,
                 },
-                SQLiteUp: []string{
-                        `CREATE TABLE expectations (
-                                id            INTEGER     NOT NULL PRIMARY KEY AUTOINCREMENT,
-                                userid        TEXT        NOT NULL,
-                                ts            BIGINT      NOT NULL,
-                                expectations  MEDIUXMTEXT  NOT NULL
-                        )`,
-                },
-                SQLiteDown: []string{
-                        `DROP TABLE expectations`,
-                },
         },
 
         // Use this is a template for more migration steps.
         // version x
         // {
         //      MySQLUp: ,
         //      MySQLDown: ,
-        //      SQLiteUp: ,
-        //      SQLiteDown: ,
         // },
 }