Terkadang muncul tugas untuk menguraikan DSL sewenang-wenang untuk bekerja lebih lanjut dengannya di tingkat kode PHP. Dan saya ingin berbagi pengalaman saya memecahkan masalah ini dengan contoh.
Untuk beberapa waktu saya telah menggunakan layanan dbdiagram untuk merancang struktur database untuk proyek yang akan datang atau yang sudah ada. Saya memilih layanan ini karena cukup mudah digunakan. Kami menggambarkan struktur tabel dalam DBML dan langsung melihat hasilnya.
, DBML , .
, : PHP , , Laravel .
, GO, , , PHP.
: , ( () , «»). () .
//
// full_name varchar [not null, unique, default: 1]
// JSON
[
{"name": "IDENT", "string": "full_name", "pos": [0, 9]},
{"name": "IDENT", "string": "varchar", "pos": [0, 17]},
{"name": "LBRACK", "string": "[", "pos": [0, 18]},
{"name": "NOT", "string": "not", "pos": [0, 22]},
{"name": "NULL", "string": "null", "pos": [0, 27]},
{"name": "COMMA", "string": ",", "pos": [0, 27]},
{"name": "UNIQUE", "string": "unique", "pos": [0, 35]},
{"name": "COMMA", "string": ",", "pos": [0, 35]},
{"name": "DEFAULT", "string": "default", "pos": [0, 44]},
{"name": "COLON", "string": ":", "pos": [0, 44]},
{"name": "INT", "string": "1", "pos": [0, 46]},
{"name": "RBRACK", "string": "]", "pos": [0, 47]}
]
, .
// DBML
Project test {
database_type: 'PostgreSQL'
Note: 'Description of the project'
}
[
{"name":"PROJECT","string":"Project","pos":[0,7]},
{"name":"IDENT","string":"test","pos":[0,12]},
{"name":"LBRACE","string":"{","pos":[0,13]},
{"name":"IDENT","string":"database_type","pos":[1,15]},
{"name":"COLON","string":":","pos":[1,15]},
{"name":"DSTRING","string":"PostgreSQL","pos":[1,18]},
{"name":"NOTE","string":"Note","pos":[2,6]},
{"name":"COLON","string":":","pos":[2,6]},
{"name":"DSTRING","string":"Description of the project","pos":[2,9]},
{"name":"RBRACE","string":"}","pos":[3,0]}
]
PROJECT
, .
<?php
//
$tokens = TokenCollection(...);
//
$token = $tokens->nextToken();
// ,
if (!$token->is(Token::IDENT) && !$token->is(Token::DSTRING)) {
throw new ParserException('Project does not have a name');
}
$name = $token->getString();
// LBRACE
$token = $tokens->nextToken();
if (!$token->is('LBRACE')) {
throw new ParserException('Expects {');
}
$project = new Project($name);
//
do {
$token = $tokens->nextToken();
switch ($token->getName()) {
case Token::IDENT:
switch ($token->getString()) {
case 'database_type':
$project->setDbType(...);
break;
default:
throw new ParserException('Expects database_type');
}
break;
// ,
case Token::NOTE:
$project->setNote(...);
break;
// ,
case 'RBRACE':
return $project;
default:
throw new ParserException(sprintf('Invalid token %s', $token->getString()));
}
} while ($tokens->valid());
50% DBML, , , , .
phplrt
PHP Russia 2021 @SerafimArts phplrt, AST. .. .
, , , DBML, EBNF. EBNF phplrt , AST. .
phplrt EBNF php , .
DBML :)))
\G(?|(?:(?:\s+)(*MARK:T_WHITESPACE))|(?:(?:\/\/[^\n]*\n)(*MARK:T_COMMENT))|(?:(?:(?<=\b)true\b)(*MARK:T_BOOL_TRUE))|(?:(?:(?<=\b)false\b)(*MARK:T_BOOL_FALSE))|(?:(?:(?<=\b)null\b)(*MARK:T_NULL))|(?:(?:(?<=\b)Project\b)(*MARK:T_PROJECT))|(?:(?:(?<=\b)Table\b)(*MARK:T_TABLE))|(?:(?:(?<=\b)as\b)(*MARK:T_TABLE_ALIAS))|(?:(?:(?<=\b)(Indexes|indexes)\b)(*MARK:T_TABLE_INDEXES))|(?:(?:(Ref|ref))(*MARK:T_TABLE_REF))|(?:(?:(?<=\b)TableGroup\b)(*MARK:T_TABLE_GROUP))|(?:(?:(?<=\b)(Enum|enum)\b)(*MARK:T_ENUM))|(?:(?:(?<=\b)(primary\ske|pk)\b)(*MARK:T_TABLE_SETTING_PK))|(?:(?:(?<=\b)unique\b)(*MARK:T_TABLE_SETTING_UNIQUE))|(?:(?:(?<=\b)increment\b)(*MARK:T_TABLE_SETTING_INCREMENT))|(?:(?:(?<=\b)default\b)(*MARK:T_TABLE_SETTING_DEFAULT))|(?:(?:(?<=\b)null\b)(*MARK:T_TABLE_SETTING_NULL))|(?:(?:(?<=\b)not\snull\b)(*MARK:T_TABLE_SETTING_NOT_NULL))|(?:(?:(?<=\b)cascade\b)(*MARK:T_REF_ACTION_CASCADE))|(?:(?:(?<=\b)restrict\b)(*MARK:T_REF_ACTION_RESTRICT))|(?:(?:(?<=\b)set\snull\b)(*MARK:T_REF_ACTION_SET_NULL))|(?:(?:(?<=\b)set\default\b)(*MARK:T_REF_ACTION_SET_DEFAULT))|(?:(?:(?<=\b)no\saction\b)(*MARK:T_REF_ACTION_NO_ACTION))|(?:(?:(?<=\b)delete\b)(*MARK:T_REF_ACTION_DELETE))|(?:(?:(?<=\b)update\b)(*MARK:T_REF_ACTION_UPDATE))|(?:(?:note:)(*MARK:T_SETTING_NOTE))|(?:(?:(?<=\b)Note\b)(*MARK:T_NOTE))|(?:(?:[0-9]+\.[0-9]+)(*MARK:T_FLOAT))|(?:(?:[0-9]+)(*MARK:T_INT))|(?:(?:('{3}|["']{1})([^'"][\s\S]*?)\1)(*MARK:T_QUOTED_STRING))|(?:(?:(`{1})([\s\S]+?)\1)(*MARK:T_EXPRESSION))|(?:(?:[a-zA-Z0-9_]+)(*MARK:T_WORD))|(?:(?:\\n)(*MARK:T_EOL))|(?:(?:\()(*MARK:T_LPAREN))|(?:(?:\))(*MARK:T_RPAREN))|(?:(?:{)(*MARK:T_LBRACE))|(?:(?:})(*MARK:T_RBRACE))|(?:(?:\[)(*MARK:T_LBRACK))|(?:(?:\])(*MARK:T_RBRACK))|(?:(?:\>)(*MARK:T_GT))|(?:(?:\<)(*MARK:T_LT))|(?:(?:,)(*MARK:T_COMMA))|(?:(?::)(*MARK:T_COLON))|(?:(?:\-)(*MARK:T_MINUS))|(?:(?:\.)(*MARK:T_DOT))|(?:(?:.+?)(*MARK:T_UNKNOWN)))
//
Project test {
database_type: 'PostgreSQL'
Note: 'Description of the project'
}
, .. , .
//
%token T_PROJECT (?<=\b)Project\b
//
%token T_NOTE (?<=\b)Note\b
// ,
%token T_QUOTED_STRING ('{3}|["']{1})([^'"][\s\S]*?)\1
//
%token T_WORD [a-zA-Z_]+
//
%token T_LBRACE {
%token T_RBRACE }
%token T_COLON :
%token T_EOL \\n
// ,
%skip T_WHITESPACE \s+
,
#Project
:
::T_PROJECT:: <T_WORD> ::T_LBRACE:: ::T_EOL::
//
::T_RBRACE:: ::EOL::
;
// #Project - ( ),
//
// ::TOKEN_NAME:: AST
// <TOKEN_NAME>
, , .
// database_type: 'PostgreSQL'
#ProjectSetting
:
<T_WORD> ::T_COLON:: (<T_WORD> | <T_QUOTED_STRING>)
;
// Note: 'Description of the project'
#Note
:
::T_NOTE:: ::T_COLON:: (<T_WORD> | <T_QUOTED_STRING>)
;
// ( <T_WORD> | <T_QUOTED_STRING> ) ,
//
#DBML
:
// DBML
// (...)*
(
Project()
// Project() |
// Table() |
// TableGroup() |
// Enum() |
// Ref()
)*
;
#Project
:
::T_PROJECT:: <T_WORD> ::T_LBRACE:: ::T_EOL::
// 0
(ProjectSetting() | Note() ::T_EOL::)*
::T_RBRACE:: ::T_EOL::
;
. , . .
xml .
<DBML offset="0">
<Project offset="0">
<T_WORD offset="8">project_name</T_WORD>
<ProjectSetting offset="27">
<T_WORD offset="27">database_type</T_WORD>
<T_QUOTED_STRING offset="42">'PostgreSQL'</T_QUOTED_STRING>
</ProjectSetting>
<Note offset="59">
<T_QUOTED_STRING offset="65">'Description of the project'</T_QUOTED_STRING>
</Note>
</Project>
</DBML>
, , XML , ?
. phplrt PHP
!!!!!! . XML , .
, .
#Project -> {
return new ProjectNode(
// $children -
// \Butschster\Dbml\Ast\Project\SettingNode
// \Butschster\Dbml\Ast\NoteNode
$token->getOffset(), $children
);
}
#ProjectSetting -> {
return new SettingNode(
// \current($children) -
// \end($children) -
$token->getOffset(), \current($children), \end($children)
);
}
#Note -> {
return new NoteNode(
// \end($children)
$token->getOffset(), \end($children)
);
}
PHP
<?php
class ProjectNode
{
private ?string $note = null;
/** @var SettingNode[] */
private array $settings = [];
private string $name;
public function __construct(
private int $offset,
array $children
)
{
foreach ($children as $child) {
if ($child instanceof NoteNode) {
$this->note = $child->getDescription();
} else if ($child instanceof SettingNode) {
$this->settings[$child->getKey()] = $child;
} else if ($child instanceof NameNode) {
$this->name = $child->getValue();
}
}
}
public function getName(): string
{
return $this->name;
}
public function getNote(): ?string
{
return $this->note;
}
public function getSettings(): array
{
return $this->settings;
}
}
class NoteNode
{
private string $description;
public function __construct(private int $offset, StringNode $string)
{
$this->description = $string->getValue();
}
public function getDescription(): string
{
return $this->description;
}
}
class SettingNode
{
private string $key;
private string $value;
public function __construct(
private int $offset, SettingKeyNode $key, StringNode $value
)
{
$this->key = $key->getValue();
$this->value = $value->getValue();
}
public function getKey(): string
{
return $this->key;
}
public function getValue(): string
{
return $this->value;
}
}
. , DBML , .
phplrt EBNF :
DBML
EBNF
XML ,
<?php
class ProjectParserTest extends TestCase
{
function test_project_with_single_line_note_should_be_parsed()
{
$this->assertAst(<<<DBML
Project project_name {
Note: 'Description of the project'
database_type: 'PostgreSQL'
}
DBML
, <<<AST
<Schema offset="0">
<Project offset="0">
<ProjectName offset="8">
<String offset="8">
<T_WORD offset="8">project_name</T_WORD>
</String>
</ProjectName>
<Note offset="27">
<String offset="33">
<T_QUOTED_STRING offset="33">'Description of the project'</T_QUOTED_STRING>
</String>
</Note>
<ProjectSetting offset="66">
<ProjectSettingKey offset="66">
<T_WORD offset="66">database_type</T_WORD>
</ProjectSettingKey>
<String offset="81">
<T_QUOTED_STRING offset="81">'PostgreSQL'</T_QUOTED_STRING>
</String>
</ProjectSetting>
</Project>
</Schema>
AST
);
}
function test_project_with_multi_line_note_should_be_parsed()
{
$this->assertAst(<<<DBML
Project project_name {
database_type: 'PostgreSQL'
Note: '''
# DBML - Database Markup Language
(database markup language) is a simple, readable DSL language designed to define database structures.
## Benefits
* It is simple, flexible and highly human-readable
* It is database agnostic, focusing on the essential database structure definition without worrying about the detailed syntaxes of each database
* Comes with a free, simple database visualiser at [dbdiagram.io](http://dbdiagram.io)
'''
}
DBML
, <<<AST
<Schema offset="0">
<Project offset="0">
<ProjectName offset="8">
<String offset="8">
<T_WORD offset="8">project_name</T_WORD>
</String>
</ProjectName>
<ProjectSetting offset="27">
<ProjectSettingKey offset="27">
<T_WORD offset="27">database_type</T_WORD>
</ProjectSettingKey>
<String offset="42">
<T_QUOTED_STRING offset="42">'PostgreSQL'</T_QUOTED_STRING>
</String>
</ProjectSetting>
<Note offset="59">
<String offset="65">
<T_QUOTED_STRING offset="65">'''
# DBML - Database Markup Language
(database markup language) is a simple, readable DSL language designed to define database structures.
## Benefits
* It is simple, flexible and highly human-readable
* It is database agnostic, focusing on the essential database structure definition without worrying about the detailed syntaxes of each database
* Comes with a free, simple database visualiser at [dbdiagram.io](http://dbdiagram.io)
'''</T_QUOTED_STRING>
</String>
</Note>
</Project>
</Schema>
AST
);
}
function test_project_with_block_note_should_be_parsed()
{
$this->assertAst(<<<DBML
Project project_name {
database_type: 'PostgreSQL'
Note {
'This is a note of this table'
}
}
DBML
, <<<AST
<Schema offset="0">
<Project offset="0">
<ProjectName offset="8">
<String offset="8">
<T_WORD offset="8">project_name</T_WORD>
</String>
</ProjectName>
<ProjectSetting offset="27">
<ProjectSettingKey offset="27">
<T_WORD offset="27">database_type</T_WORD>
</ProjectSettingKey>
<String offset="42">
<T_QUOTED_STRING offset="42">'PostgreSQL'</T_QUOTED_STRING>
</String>
</ProjectSetting>
<Note offset="59">
<String offset="74">
<T_QUOTED_STRING offset="74">'This is a note of this table'</T_QUOTED_STRING>
</String>
</Note>
</Project>
</Schema>
AST
);
}
}
DBML EBNF, phplrt php , ( ).
yet another DBML parser written on PHP8 ( ) - https://github.com/butschster/dbml-parser
Tahap pertama dalam rencana saya telah selesai. Sekarang tinggal membuat generator model dan migrasi.
Sebagai hasil dari bekerja dengan alat phplrt, saya ingin menyampaikan rasa hormat dan hormat saya kepada @SerafimArts untuknya, yang membantu secara radikal mengubah pendekatan penguraian bahasa dan memecahkan masalah saya.
Terima kasih khusus kepada @greabock dan @SerafimArts atas bantuannya dalam mempersiapkan materi dan bantuan dalam mengembangkan parser.
Tautan
Pengurai DBML
Alat Phplrt
Dokumentasi Phlrt