Bài giảng Phát triển phần mềm nguồn mở - Chương 2: PHP Standards Recommendations - Nguyễn Hữu Thể

PHP Standards Recommendations
Nguyễn Hữu Thể
PHÁT TRIỂN PHẦN MỀM NGUỒN MỞ
Content
 Basic Coding Standard
 Coding Style Guide
 Logger Interface
 Autoloading Standard
 Caching Interface
 HTTP Message Interface
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Index by Status (Accepted)
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Num Title Editor Coordinator Sponsor
1 Basic Coding Standard Paul M. Jones N/A N/A
2 Coding Style Guide Paul M. Jones N/A N/A
3 Logger Interface
Jordi 
Boggiano
N/A N/A
4 Autoloading Standard Paul M. Jones Phil Sturgeon Larry Garfield
6 Caching Interface Larry Garfield
Paul 
Dragoonis
Robert Hafner
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HTTP Message 
Interface
Matthew 
Weier 
O'Phinney
Beau 
Simensen
Paul M. Jones
13 Hypermedia Links Larry Garfield
Matthew 
Weier 
O'Phinney
Marc 
Alexander
PSR-1: Basic Coding Standard
1. Overview
 Files MUST use only <?php and <?= tags.
 Files MUST use only UTF-8 without BOM for PHP code.
 Files SHOULD either declare symbols (classes, functions,
constants, etc.) or cause side-effects (e.g. generate output, change
.ini settings, etc.) but SHOULD NOT do both.
 Namespaces and classes MUST follow an "autoloading" PSR:
[PSR-0, PSR-4].
 Class names MUST be declared in StudlyCaps.
 Class constants MUST be declared in all upper case with underscore
separators.
 Method names MUST be declared in camelCase. 4
PSR-1: Basic Coding Standard
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<?php
// side effect: change ini settings
ini_set('error_reporting', E_ALL);
// side effect: loads a file
include "file.php";
// side effect: generates output
echo "\n";
// declaration
function foo()
{
// function body
}
<?php
// declaration
function foo()
{
// function body
}
// conditional declaration is *not* a side 
effect
if (! function_exists('bar')) {
function bar()
{
// function body
}
}
SHOULD NOT SHOULD
PSR-1: Basic Coding Standard
Namespace and Class Names
 Namespaces and classes MUST follow an "autoloading" PSR:
[PSR-0, PSR-4].
 Class names MUST be declared in StudlyCaps.
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// PHP 5.3 and later:
namespace Vendor\Model;
class Foo
{
}
PSR-1: Basic Coding Standard
Class Constants, Properties, and Methods
 The term "class" refers to all classes, interfaces, and traits.
 Class constants MUST be declared in all upper case with
underscore separators.
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namespace Vendor\Model;
class Foo
{
const VERSION = '1.0';
const DATE_APPROVED = '2012-06-01';
}
PSR-1: Basic Coding Standard
 Properties
• This guide intentionally avoids any recommendation
regarding the use of $StudlyCaps, $camelCase, or
$under_score property names.
 Methods
• Method names MUST be declared in camelCase().
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PSR-2: Coding Style Guide
 Code MUST use 4 spaces for indenting, not tabs.
 There MUST NOT be a hard limit on line length; the soft limit
MUST be 120 characters; lines SHOULD be 80 characters or
less.
 There MUST be one blank line after the namespace
declaration, and there MUST be one blank line after the block
of use declarations.
 Opening braces for classes MUST go on the next line, and
closing braces MUST go on the next line after the body.
 Opening braces for methods MUST go on the next line, and
closing braces MUST go on the next line after the body.
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PSR-2: Coding Style Guide
 Control structure keywords MUST have one space after them;
method and function calls MUST NOT.
 Opening braces for control structures MUST go on the same
line, and closing braces MUST go on the next line after the
body.
 Opening parentheses for control structures MUST NOT have a
space after them, and closing parentheses for control
structures MUST NOT have a space before.
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namespace Vendor\Package;
use FooInterface;
use BarClass as Bar;
use OtherVendor\OtherPackage\BazClass;
class Foo extends Bar implements FooInterface
{
public function sampleMethod($a, $b = null)
{
if ($a === $b) {
bar();
} elseif ($a > $b) {
$foo->bar($arg1);
} else {
BazClass::bar($arg2, $arg3);
}
}
final public static function bar()
{
// method body
}
}
PSR-3: Logger Interface
 The LoggerInterface exposes eight methods to write logs to
the eight RFC 5424 levels (debug, info, notice, warning, error,
critical, alert, emergency).
 A ninth method, log, accepts a log level as the first argument.
Calling this method with one of the log level constants MUST
have the same result as calling the level-specific method.
 Users SHOULD NOT use a custom level without knowing for
sure the current implementation supports it.
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PSR-4: Autoloader
 The term "class" refers to classes, interfaces, traits, and other
similar structures.
 A fully qualified class name has the following form:
\(\)*\
 The fully qualified class name MUST have a top-level
namespace name, also known as a "vendor namespace".
 The fully qualified class name MAY have one or more sub-
namespace names.
 The fully qualified class name MUST have a terminating class
name.
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PSR-4: Autoloader
 Underscores have no special meaning in any portion of the
fully qualified class name.
 Alphabetic characters in the fully qualified class name MAY
be any combination of lower case and upper case.
 All class names MUST be referenced in a case-sensitive
fashion.
 When loading a file that corresponds to a fully qualified class
name ...
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PSR-4: Autoloader
 The contiguous sub-namespace names after the "namespace
prefix" correspond to a subdirectory within a "base directory",
in which the namespace separators represent directory
separators. The subdirectory name MUST match the case of
the sub-namespace names.
 The terminating class name corresponds to a file name ending
in .php. The file name MUST match the case of the
terminating class name.
 Autoloader implementations MUST NOT throw exceptions,
MUST NOT raise errors of any level, and SHOULD NOT
return a value.
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PSR-6: # Introduction
 The goal of this PSR is to allow developers to create
cache-aware libraries that can be integrated into
existing frameworks and systems without the need
for custom development.
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PSR-7: HTTP message interfaces
 This document describes common interfaces for
representing HTTP messages as described in :
• RFC 7230
• RFC 7231,
• URIs for use with HTTP messages as described in RFC
3986.
 HTTP messages are the foundation of web
development.
• Web browsers and HTTP clients such as cURL create HTTP
request messages that are sent to a web server, which
provides an HTTP response message.
• Server-side code receives an HTTP request message, and
returns an HTTP response message.
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