package schema import ( "crypto/sha1" "encoding/hex" "fmt" "regexp" "strings" "unicode/utf8" "github.com/jinzhu/inflection" ) // Namer namer interface type Namer interface { TableName(table string) string SchemaName(table string) string ColumnName(table, column string) string JoinTableName(joinTable string) string RelationshipFKName(Relationship) string CheckerName(table, column string) string IndexName(table, column string) string } // Replacer replacer interface like strings.Replacer type Replacer interface { Replace(name string) string } // NamingStrategy tables, columns naming strategy type NamingStrategy struct { TablePrefix string SingularTable bool NameReplacer Replacer NoLowerCase bool } // TableName convert string to table name func (ns NamingStrategy) TableName(str string) string { if ns.SingularTable { return ns.TablePrefix + ns.toDBName(str) } return ns.TablePrefix + inflection.Plural(ns.toDBName(str)) } // SchemaName generate schema name from table name, don't guarantee it is the reverse value of TableName func (ns NamingStrategy) SchemaName(table string) string { table = strings.TrimPrefix(table, ns.TablePrefix) if ns.SingularTable { return ns.toSchemaName(table) } return ns.toSchemaName(inflection.Singular(table)) } // ColumnName convert string to column name func (ns NamingStrategy) ColumnName(table, column string) string { return ns.toDBName(column) } // JoinTableName convert string to join table name func (ns NamingStrategy) JoinTableName(str string) string { if !ns.NoLowerCase && strings.ToLower(str) == str { return ns.TablePrefix + str } if ns.SingularTable { return ns.TablePrefix + ns.toDBName(str) } return ns.TablePrefix + inflection.Plural(ns.toDBName(str)) } // RelationshipFKName generate fk name for relation func (ns NamingStrategy) RelationshipFKName(rel Relationship) string { return ns.formatName("fk", rel.Schema.Table, ns.toDBName(rel.Name)) } // CheckerName generate checker name func (ns NamingStrategy) CheckerName(table, column string) string { return ns.formatName("chk", table, column) } // IndexName generate index name func (ns NamingStrategy) IndexName(table, column string) string { return ns.formatName("idx", table, ns.toDBName(column)) } func (ns NamingStrategy) formatName(prefix, table, name string) string { formattedName := strings.Replace(strings.Join([]string{ prefix, table, name, }, "_"), ".", "_", -1) if utf8.RuneCountInString(formattedName) > 64 { h := sha1.New() h.Write([]byte(formattedName)) bs := h.Sum(nil) formattedName = fmt.Sprintf("%v%v%v", prefix, table, name)[0:56] + hex.EncodeToString(bs)[:8] } return formattedName } var ( // https://github.com/golang/lint/blob/master/lint.go#L770 commonInitialisms = []string{"API", "ASCII", "CPU", "CSS", "DNS", "EOF", "GUID", "HTML", "HTTP", "HTTPS", "ID", "IP", "JSON", "LHS", "QPS", "RAM", "RHS", "RPC", "SLA", "SMTP", "SSH", "TLS", "TTL", "UID", "UI", "UUID", "URI", "URL", "UTF8", "VM", "XML", "XSRF", "XSS"} commonInitialismsReplacer *strings.Replacer ) func init() { commonInitialismsForReplacer := make([]string, 0, len(commonInitialisms)) for _, initialism := range commonInitialisms { commonInitialismsForReplacer = append(commonInitialismsForReplacer, initialism, strings.Title(strings.ToLower(initialism))) } commonInitialismsReplacer = strings.NewReplacer(commonInitialismsForReplacer...) } func (ns NamingStrategy) toDBName(name string) string { if name == "" { return "" } if ns.NameReplacer != nil { name = ns.NameReplacer.Replace(name) } if ns.NoLowerCase { return name } var ( value = commonInitialismsReplacer.Replace(name) buf strings.Builder lastCase, nextCase, nextNumber bool // upper case == true curCase = value[0] <= 'Z' && value[0] >= 'A' ) for i, v := range value[:len(value)-1] { nextCase = value[i+1] <= 'Z' && value[i+1] >= 'A' nextNumber = value[i+1] >= '0' && value[i+1] <= '9' if curCase { if lastCase && (nextCase || nextNumber) { buf.WriteRune(v + 32) } else { if i > 0 && value[i-1] != '_' && value[i+1] != '_' { buf.WriteByte('_') } buf.WriteRune(v + 32) } } else { buf.WriteRune(v) } lastCase = curCase curCase = nextCase } if curCase { if !lastCase && len(value) > 1 { buf.WriteByte('_') } buf.WriteByte(value[len(value)-1] + 32) } else { buf.WriteByte(value[len(value)-1]) } ret := buf.String() return ret } func (ns NamingStrategy) toSchemaName(name string) string { result := strings.Replace(strings.Title(strings.Replace(name, "_", " ", -1)), " ", "", -1) for _, initialism := range commonInitialisms { result = regexp.MustCompile(strings.Title(strings.ToLower(initialism))+"([A-Z]|$|_)").ReplaceAllString(result, initialism+"$1") } return result }