Bringing Old Legacy Apps To PHP 7 and Beyond - PNWPHP 2017

Talk given at Pacific Northwest PHP 2017

Most developers don't get the luxury of working on a greenfield project using a web framework of their choice. Often times we find ourselves inheriting a legacy codebase written years ago for an end-of-life version of PHP and a now-defunct web framework. The initial temptation might be, "I'll just rewrite all this on x framework". But hold on there my framework friend, a rewrite is costly and is rarely the correct answer. We'll discuss some common pitfalls when getting a legacy codebase ready for PHP 7 and what we can do to make the upgrade path as painless as possible. These incremental changes will keep the business running while improving security, stability and maintainability of the codebase.

Transcript

1. Bringing Old Legacy Apps To September 9th, 2017 Sammy Kaye Powers @SammyK PHP 7 & Beyond
2. joind.in/talk/228f1 @SammyK #pnwphp Slides Get the joind.in/talk/228f1
3. joind.in/talk/228f1 @SammyK #pnwphp Upgrade Path 7.1 Less about More about Refactoring Strategies to
4. joind.in/talk/228f1 @SammyK #pnwphp Codebase
5. joind.in/talk/228f1 @SammyK #pnwphp
6. joind.in/talk/228f1 @SammyK #pnwphp I’ll just rewrite this in ____________!
7. joind.in/talk/228f1 @SammyK #pnwphp I’ll just rewrite this in ____________!
8. joind.in/talk/228f1 @SammyK #pnwphp I’ll just rewrite this in ____________! Laravel
9. joind.in/talk/228f1 @SammyK #pnwphp I’ll just rewrite this in ____________!
10. joind.in/talk/228f1 @SammyK #pnwphp rewrite from scratch? Why not
11. joind.in/talk/228f1 @SammyK #pnwphp Functionality Existing Codebase Fancy-pants rewrite
12. joind.in/talk/228f1 @SammyK #pnwphp Functionality Existing Codebase Fancy-pants rewrite
13. joind.in/talk/228f1 @SammyK #pnwphp Functionality Existing Codebase Fancy-pants rewrite
14. joind.in/talk/228f1 @SammyK #pnwphp Functionality Existing Codebase Fancy-pants rewrite
15. joind.in/talk/228f1 @SammyK #pnwphp Functionality Existing Codebase Fancy-pants rewrite
16. joind.in/talk/228f1 @SammyK #pnwphp Refactoring Martin Fowler http://martinfowler.com/books/refactoring.html
17. joind.in/talk/228f1 @SammyK #pnwphp “Legacy” /leɡəsē/ • Requires an EOL version of PHP • No automated tests • Has outdated dependencies • No autoloading • No sign of “single responsibility”
18. joind.in/talk/228f1 @SammyK #pnwphp
19. joind.in/talk/228f1 @SammyK #pnwphp “Legacy” We’ll assume …means any code that is running on PHP 5.x (at least for this talk)
20. joind.in/talk/228f1 @SammyK #pnwphp Expectations
21. joind.in/talk/228f1 @SammyK #pnwphp elePHPant How to eat an
22. joind.in/talk/228f1 @SammyK #pnwphp ZERO Step
23. joind.in/talk/228f1 @SammyK #pnwphp Around Poke
24. joind.in/talk/228f1 @SammyK #pnwphp Around Poke • Composer &/or autoloading? • Documentation? (Look for hidden docs!) • Framework/Dependencies? (How out-dated?) • How is database layer implemented? • How is config handled? • How are front-end assets handled? • Are there tests? • Production env (PHP version)
25. joind.in/talk/228f1 @SammyK #pnwphp Analysis Static
26. phploc
27. phploc
28. phpcpd
29. joind.in/talk/228f1 @SammyK #pnwphp Consider the Stakeholders
30. joind.in/talk/228f1 @SammyK #pnwphp Consider the Stakeholders I’ll need 80 hours to refactor the user auth & ACL
31. joind.in/talk/228f1 @SammyK #pnwphp Consider the Stakeholders • Most critical security holes • Most critical bugs • Most critical features • Use data from static analysis Make a plan
32. joind.in/talk/228f1 @SammyK #pnwphp ONE Step
33. joind.in/talk/228f1 @SammyK #pnwphp 5.(wat) Get it running on
34. Environment Get it running on your local
35. joind.in/talk/228f1 @SammyK #pnwphp Git with an SCM
36. joind.in/talk/228f1 @SammyK #pnwphp
37. joind.in/talk/228f1 @SammyK #pnwphp Git Get with master original local-config
38. joind.in/talk/228f1 @SammyK #pnwphp Fix all the errors
40. joind.in/talk/228f1 @SammyK #pnwphp TWO Step
41. joind.in/talk/228f1 @SammyK #pnwphp 7.1 Get it running on
42. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 Is almost 2 years old!
43. joind.in/talk/228f1 @SammyK #pnwphp 2
44. joind.in/talk/228f1 @SammyK #pnwphp years
45. joind.in/talk/228f1 @SammyK #pnwphp old!
46. joind.in/talk/228f1 @SammyK #pnwphp OLD
47. joind.in/talk/228f1 @SammyK #pnwphp http://php.net/supported-versions.php > 3 months Active support (bug fixes) for PHP 7.0 ends
48. joind.in/talk/228f1 @SammyK #pnwphp OLD PHP 7.0 is
49. 7.1 ✓Performance increase PHP 7 features ✓
50. 7.1
51. BC is totes amaze
52. joind.in/talk/228f1 @SammyK #pnwphp PHP 7 enlightenment The path to 7.1 5.6
53. joind.in/talk/228f1 @SammyK #pnwphp 7.1 5.5 PHP 7 enlightenment The path to
54. joind.in/talk/228f1 @SammyK #pnwphp 7.1 5.4 PHP 7 enlightenment The path to
55. joind.in/talk/228f1 @SammyK #pnwphp 7.1 <= 5.3 PHP 7 enlightenment The path to
56. joind.in/talk/228f1 @SammyK #pnwphp THREE Step
57. joind.in/talk/228f1 @SammyK #pnwphp Fix all the PHP 7 errors
58. joind.in/talk/228f1 @SammyK #pnwphp PHP 7 Quick tricks to refactor to (in order of ease)
59. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 “Gotchas” ASP and <script> PHP tags removed
60. <% %> <%= %> <script language=“php"> </script>
61. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 “Gotchas” removed $HTTP_RAW_POST_DATA
62. joind.in/talk/228f1 @SammyK #pnwphp php://input instead read from
63. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 “Gotchas” PHP-4-style constructors deprecated
64. joind.in/talk/228f1 @SammyK #pnwphp
65. joind.in/talk/228f1 @SammyK #pnwphp
66. PHP 7.0 “Gotchas” Some functions got the ax ereg* functions
67. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 “Gotchas” “There’s a shim for that!”
68. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 “Gotchas” “There’s a shim for that!” ereg* functions bbrala/php7-ereg-shim (Björn Brala)
69. joind.in/talk/228f1 @SammyK #pnwphp
70. PHP 7.0 “Gotchas” Another one bites the dust ext/mysql functions
71. PHP 7.0 “Gotchas” “There’s a shim for that!” ext/mysql functions dshafik/php7-mysql-shim (Davey Shafik)
72. joind.in/talk/228f1 @SammyK #pnwphp Caveats though…
73. PHP 7.0 “Gotchas” Another bird with the PHP 7.0 stone ext/mssql functions instead use sqlsrv_*(), odbc_*(), PDO
74. PHP 7.0 “Gotchas” A few others for the chopping block Some ext/mcrypt functions, et. al.
75. PHP 7.0 “Gotchas” Scalar Type Declarations New reserved keywords: string, int, bool, float
77. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 “Gotchas” Uniform Variable Syntax Change in evaluating indirect expressions
78. joind.in/talk/228f1 @SammyK #pnwphp
79. Variable variables string(5) "world"
80. joind.in/talk/228f1 @SammyK #pnwphp
81. string(16) "PHP 5.x I see..." 5.x
82. 7.x
83. joind.in/talk/228f1 @SammyK #pnwphp
84. joind.in/talk/228f1 @SammyK #pnwphp 5.x
85. joind.in/talk/228f1 @SammyK #pnwphp 5.x
86. joind.in/talk/228f1 @SammyK #pnwphp 5.x string(16) "PHP 5.x I see..."
87. joind.in/talk/228f1 @SammyK #pnwphp 7.x
88. joind.in/talk/228f1 @SammyK #pnwphp 7.x
89. joind.in/talk/228f1 @SammyK #pnwphp 7.x
90. joind.in/talk/228f1 @SammyK #pnwphp 7.x Notice: Array to string conversion in / foo.php on line 6 Notice: Undefined variable: Array in / foo.php on line 6
91. joind.in/talk/228f1 @SammyK #pnwphp Funky
92. joind.in/talk/228f1 @SammyK #pnwphp
94. joind.in/talk/228f1 @SammyK #pnwphp 7.x 5.x
95. joind.in/talk/228f1 @SammyK #pnwphp FOUR Step
96. joind.in/talk/228f1 @SammyK #pnwphp Code!
97. joind.in/talk/228f1 @SammyK #pnwphp Tests TESTS Tests
98. joind.in/talk/228f1 @SammyK #pnwphp PHPUnit?
99. joind.in/talk/228f1 @SammyK #pnwphp Acceptance Tests
100. joind.in/talk/228f1 @SammyK #pnwphp Codeception
101. joind.in/talk/228f1 @SammyK #pnwphp Behavior-driven testing framework
102. joind.in/talk/228f1 @SammyK #pnwphp Composer + Autoloading
103. joind.in/talk/228f1 @SammyK #pnwphp
104. Feature (User Story)
105. joind.in/talk/228f1 @SammyK #pnwphp Scenario
106. joind.in/talk/228f1 @SammyK #pnwphp
107. joind.in/talk/228f1 @SammyK #pnwphp Scenario
109. joind.in/talk/228f1 @SammyK #pnwphp FIVE Step “The Refactoring Loop”
110. joind.in/talk/228f1 @SammyK #pnwphp refactorLoop:
111. joind.in/talk/228f1 @SammyK #pnwphp Start small
113. joind.in/talk/228f1 @SammyK #pnwphp Make sure there’s a test
114. joind.in/talk/228f1 @SammyK #pnwphp Refactor
115. joind.in/talk/228f1 @SammyK #pnwphp Run your tests
116. joind.in/talk/228f1 @SammyK #pnwphp goto refactorLoop;
117. joind.in/talk/228f1 @SammyK #pnwphp lets you refactor like a BEAST
118. PHPUnit Don’t forget about
119. joind.in/talk/228f1 @SammyK #pnwphp End-to-end is great! Except when…
120. joind.in/talk/228f1 @SammyK #pnwphp It’s Not
121. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 Features
122. joind.in/talk/228f1 @SammyK #pnwphp random_int() random_bytes() PHP 7.0 Features CSPRNG!!
123. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 Features Scalar Type Declarations
124. PHP 7.0 Features Scalar Type Declarations function foo(string $name,
 int $age,
 bool $isGreat,
 float $income)
 { /* */ }
125. PHP 7.0 Features Scalar Type Declarations function foo(string $name,
 int $age,
 bool $isGreat,
 float $income)
 { /* */ }
126. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 Features Return type declarations
127. PHP 7.0 Features Return type declarations /**
 * @return Collection
 */
 public function foo()
 {
 }
128. PHP 7.0 Features /**
 * @return Collection
 */
 public function foo()
 {
 } Return type declarations
129. PHP 7.0 Features public function foo(): Collection
 {
 } Return type declarations
130. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 Features Null coalesce operator
131. PHP 7.0 Features $bar = isset($_GET[‘foo’]) ? $_GET[‘foo’] : null; Null coalesce operator $bar = $_GET[‘foo’] ?? null;
132. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.0 Features Insane speed improvements
133. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.1 Considerations & Features
134. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.1 Considerations deprecated ext/mcrypt Soon to be...
135. joind.in/talk/228f1 @SammyK #pnwphp rand() & mt_rand() changes PHP 7.1 Considerations
136. joind.in/talk/228f1 @SammyK #pnwphp
137. joind.in/talk/228f1 @SammyK #pnwphp Totes Samezies!
138. joind.in/talk/228f1 @SammyK #pnwphp array_rand() Now with even distribution! PHP 7.1 Considerations
139. joind.in/talk/228f1 @SammyK #pnwphp Void return types PHP 7.1 Features
140. public function foo(): void
 {
 } Void return types PHP 7.1 Features
141. joind.in/talk/228f1 @SammyK #pnwphp Nullable types (kinda like union types for null) PHP 7.1 Features
142. Nullable types function foo(string $name)
 { /* */ } PHP 7.1 Features
143. Nullable types function foo(?string $name)
 { /* */ } PHP 7.1 Features
144. Nullable types function foo(string $name = null)
 { /* */ } foo(); PHP 7.1 Features
145. Nullable types foo(); function foo(?string $name)
 { /* */ } foo(null); PHP 7.1 Features
146. Nullable types function foo(): ?string { return null; } PHP 7.1 Features
147. joind.in/talk/228f1 @SammyK #pnwphp Class constant visibility PHP 7.1 Features
148. Class constant visibility class Foo {
 public const FOO = 0; protected const BAR = 1; private const BAZ = 2; } PHP 7.1 Features
149. joind.in/talk/228f1 @SammyK #pnwphp `iterable` pseudo-type PHP 7.1 Features
150. `iterable` pseudo-type function foo(iterable $a)
 { /* */ } $b = []; foo($b); class C implements Iterator {} $b = new C; foo($b); PHP 7.1 Features
151. `iterable` pseudo-type class D implements IteratorAggregate {} foo(new D); Traversable Or instance of PHP 7.1 Features
152. joind.in/talk/228f1 @SammyK #pnwphp And beyond?
153. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 Considering
154. PHP 7.2 considerations re(moved) ext/mcrypt
155. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations Argon2 Password Hash password_*() (Could become new default in PHP 7.3/8.0)
156. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations sodium_*()
157. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations Trailing Comma
158. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations Undefined Constants
159. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations
160. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations
161. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations Type Annotation object
162. joind.in/talk/228f1 @SammyK #pnwphp PHP 7.2 considerations
163. joind.in/talk/228f1 @SammyK #pnwphp 7.2 Deprecations (Will be removed by PHP 8.0)
164. joind.in/talk/228f1 @SammyK #pnwphp Some tools I like
165. vlucas/phpdotenv .env No peeking! No peeking!
166. vlucas/phpdotenv NotSecure :(
167. Env vars aren’t designed for secrets (shared with child processes, etc) Error messages can contain dump of env vars (filp/whoops)
168. joind.in/talk/228f1 @SammyK #pnwphp Some tools I like pimple/pimple
169. joind.in/talk/228f1 @SammyK #pnwphp Some tools I like monolog/monolog
170. joind.in/talk/228f1 @SammyK #pnwphp Some tools I like nikic/fast-route
171. joind.in/talk/228f1 @SammyK #pnwphp Some tools I like illuminate/database
172. joind.in/talk/228f1 @SammyK #pnwphp Some tools I like symfony/console
173. joind.in/talk/228f1 @SammyK #pnwphp Create a PHP application without a framework https://github.com/PatrickLouys/no-framework-tutorial Patrick Louys
174. joind.in/talk/228f1 @SammyK #pnwphp Big-picture Refactoring
175. joind.in/talk/228f1 @SammyK #pnwphp Constant refactoring is the key to managing legacy codebases
176. joind.in/talk/228f1 @SammyK #pnwphp Constant refactoring is the key to managing legacy codebases
177. joind.in/talk/228f1 @SammyK #pnwphp Resources 013: TDD & BDD In PHP 055: Acceptance Testing with Behat 017: Modernizing Legacy Codebases in PHP
178. joind.in/talk/228f1 @SammyK #pnwphp Modernizing Legacy Applications in PHP https://leanpub.com/mlaphp Paul M. Jones
179. joind.in/talk/228f1 @SammyK #pnwphp Refactoring Martin Fowler http://martinfowler.com/books/refactoring.html
180. I have stickers! Takk! (thanks) @SammyK SammyK.me Host of @PHPRoundtable @ChiPHPUG West Coast Swing /talk/228f1