Essential Books

Error Reporting

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By default PHP will output errors, warnings and notice messages directly on the page if something unexpected in a script occurs. This is useful for resolving specific issues with a script but at the same time it outputs information you don’t want your users to know.

Therefore it’s good practice to avoid displaying those messages which will reveal information about your server, like your directory tree for example, in production environments. In a development or testing environment these messages may still be useful to display for debugging purposes.

A quick solution

You can turn them off so the messages don’t show at all, however this makes debugging your script harder. 

<?php
  ini_set("display_errors", "0");
?>

Or change them directly in the php.ini. 

display_errors = 0

Handling errors

A better option would be to store those error messages to a place they are more useful, like a database: 

set_error_handler(function($errno , $errstr, $errfile, $errline){
  try{
    $pdo = new PDO("mysql:host=hostname;dbname=databasename", 'dbuser', 'dbpwd', [
      PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
    ]);

    if($stmt = $pdo->prepare("INSERT INTO `errors` (no,msg,file,line) VALUES (?,?,?,?)")){
      if(!$stmt->execute([$errno, $errstr, $errfile, $errline])){
        throw new Exception('Unable to execute query');
      }
    } else {
      throw new Exception('Unable to prepare query');
    }
  } catch (Exception $e){
    error_log('Exception: ' . $e->getMessage() . PHP_EOL . "$errfile:$errline:$errno | $errstr");
  }
});

This method will log the messages to the database and if that fails to a file instead of echoing it directly into the page. This way you can track what users are experiencing on your website and notify you immediately if something go’s wrong.

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Security:
* Security
* PHP Version Leakage
* Cross-Site Scripting XSS
* Cross-Site Request Forgery
* Command Line Injection
* File Inclusion
* Stripping Tags
* Error Reporting
* Uploading files
Table Of Contents
0 Getting started
1 Variables
2 Arrays
3 Functional programming
4 Types
5 Autoloading primer
6 Exception handling and error reporting
7 Working with dates and time
8 Sending email
9 Sessions
10 Cookies
11 Classes and objects
12 Password hashing
13 Output buffering
14 JSON
15 SOAP
16 Reflection
17 cURL
18 Dependency injection
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21 Traits
22 Namespaces
23 Parsing HTML
24 Composer dependency manager
25 Magic methods
26 Alternative syntax for control structures
27 File handling
28 Magic constants
29 Type hinting
30 Multi-threading extension
31 Filters, filter functions
32 Generators
33 Operators
34 Constants
35 UTF-8
36 URLs
37 Object serialization
38 PHPDoc
39 Contributing to PHP Manual
40 String parsing
41 Loops
42 Control structures
43 Serialization
44 Closur
45 Reading request data
46 Type juggling and non-strict comparison issues
47 Security
48 PHP MySQLi
49 Command Line Interface CLI
50 Localization
51 Debugging
52 Superglobal variables
53 Unit testing
54 Variable scope
55 References
56 Compilation errors and warning
57 Installing PHP on Windows
58 DateTime class
59 Headers manipulation
60 Performance
61 Common Errors
62 Installing on Linux / Unix
63 Contributing to PHP Core
64 Coding conventions
65 Using MongoDB
66 Asynchronous programming
67 Using SQLSRV
68 Unicode Support
69 Functions
70 Create PDF files
71 Hot to detect client IP address
72 YAML
73 Image processing with GD
74 Multiprocessing
75 SOAP Server
76 Machine learning
77 Cache
78 Streams
79 Array iteration
80 Cryptography
81 PDO
82 SQLite3
83 Sockets
84 Outputting the value of a variable
85 String formatting
86 Compile PHP extensions
87 MongoDB
88 Manipulating an array
89 Executing upon an array
90 Processing multiple arrays together
91 SPL data structures
92 Comments
93 IMAP
94 Redis
95 Imagick
96 SimplXML
97 HTTP Authentication
98 Recipies
99 BC Math Binary Calculator
100 Docker deployment
101 WebSockets
102 APCu
103 Design patterns
104 Secure remember me
105 PHP mysqli
106 PHP built-in server
107 How to break down an URL
108 PSR
109 Contributors