Disallowed method and function calls plug-in for PHPStan
PHPStan rules to detect disallowed calls and more, without running the code.
There are some functions, methods, and constants which should not be used in production code. One good example is
it is often used to quickly debug problems but should be removed before commiting the code. And sometimes it's not.
Another example would be a generic logger. Let's say you're using one of the generic logging libraries but you have your own logger that will add some more info, or sanitize data, before calling the generic logger. Your code should not call the generic logger directly but should instead use your custom logger.
This PHPStan extension will detect such usage, if configured. It should be noted that this extension is not a way to defend against or detect hostile developers, as they can obfuscate the calls for example. This extension is meant to be another pair of eyes, detecting your own mistakes, it doesn't aim to detect-all-the-things.
Tests will provide examples what is currently detected. If it's not covered by tests, it might be, but most probably will not be detected.
*Test.php files are the tests, start with those, the analyzed test code is in src, required test classes in libs.
Install the extension using Composer:
composer require --dev spaze/phpstan-disallowed-calls
PHPStan, the PHP Static Analysis Tool, is a requirement.
If you use phpstan/extension-installer, you are all set and can skip to configuration.
For manual installation, add this to your
includes: - vendor/spaze/phpstan-disallowed-calls/extension.neon
You can start by including
disallowed-dangerous-calls.neon in your
includes: - vendor/spaze/phpstan-disallowed-calls/disallowed-dangerous-calls.neon
disallowed-dangerous-calls.neon can also serve as a template when you'd like to extend the configuration to disallow some other functions or methods, copy it and modify to your needs.
You can also allow a previously disallowed dangerous call in a defined path (see below) in your own config by using the same
If you want to disallow program execution functions (
shell_exec() & friends) including the backtick operator (
`...`, disallowed when
shell_exec() is disallowed), include
includes: - vendor/spaze/phpstan-disallowed-calls/disallowed-execution-calls.neon
I'd recommend you include both:
includes: - vendor/spaze/phpstan-disallowed-calls/disallowed-dangerous-calls.neon - vendor/spaze/phpstan-disallowed-calls/disallowed-execution-calls.neon
To disallow some insecure or potentially insecure calls (like
includes: - vendor/spaze/phpstan-disallowed-calls/disallowed-insecure-calls.neon
Some function calls are better when done for example with some parameters set to a defined value ("strict calls"). For example
in_array() better also check for types to prevent some type juggling bugs. Include
disallowed-loose-calls.neon to disallow calls without such parameters set ("loose calls").
includes: - vendor/spaze/phpstan-disallowed-calls/disallowed-loose-calls.neon
There are several different types (and configuration keys) that can be disallowed:
disallowedMethodCalls- for detecting
disallowedStaticCalls- for static calls
disallowedFunctionCalls- for functions like
disallowedConstants- for constants like
DateTime::ISO8601(which needs to be split to
constant: ISO8601in the configuration, see notes below)
disallowedNamespaces- for usages of classes from a namespace
Use them to add rules to your
phpstan.neon config file. I like to use a separate file (
disallowed-calls.neon) for these which I'll include later on in the main
phpstan.neon config file. Here's an example, update to your needs:
parameters: disallowedMethodCalls: - method: 'PotentiallyDangerous\Logger::log()' message: 'use our own logger instead' - method: 'Redis::connect()' message: 'use our own Redis instead' disallowedStaticCalls: - method: 'PotentiallyDangerous\Debugger::log()' message: 'use our own logger instead' disallowedFunctionCalls: - function: 'var_dump()' message: 'use logger instead' - function: 'print_r()' message: 'use logger instead' disallowedConstants: - constant: 'DATE_ISO8601' message: 'use DATE_ATOM instead' - class: 'DateTimeInterface' constant: 'ISO8601' message: 'use DateTimeInterface::ATOM instead' disallowedNamespaces: - namespace: 'Symfony\Component\HttpFoundation\RequestStack' message: 'pass Request via controller instead' allowIn: - tests/* - namespace: 'Assert\*' message: 'use Webmozart\Assert instead'
message key is optional. Functions and methods can be specified with or without
() is not recommended though to avoid confusing method calls with class constants.
Use wildcard (
*) to ignore all functions, methods, namespaces starting with a prefix, for example:
parameters: disallowedFunctionCalls: - function: 'pcntl_*()'
The wildcard makes most sense when used as the rightmost character of the function or method name, optionally followed by
(), but you can use it anywhere for example to disallow all functions that end with
function: '*y()'. The matching is powered by
fnmatch so you can use even multiple wildcards if you wish because wy nt.
You can treat some language constructs as functions and disallow it in
disallowedFunctionCalls. Currently detected language constructs are:
To disallow naive object creation (
new ClassName() or
new $classname), disallow
disallowedMethodCalls. Works even when there's no constructor defined in that class.
Constants are a special breed. First, a constant needs to be disallowed on the declaring class. That means, that instead of disallowing
DateTimeImmutable::ISO8601, you need to disallow
The reason for this is that one might expect that disallowing e.g.
Date::ISO8601 (disallowing on a "used on" class) would also disallow
DateTimeImmutable::ISO8601, which unfortunately wouldn't be the case.
Second, disallowing constants doesn't support wildcards. The only real-world use case I could think of is the
Date*::CONSTANT case and that can be easily solved by disallowing
Last but not least, class constants have to be specified using two keys:
parameters: disallowedConstants: - class: 'DateTimeInterface' constant: 'ISO8601' message: 'use DateTimeInterface::ATOM instead'
Using the fully-qualified name would result in the constant being replaced with its actual value. Otherwise, the extension would see
constant: "Y-m-d\TH:i:sO" instead of
constant: DateTimeInterface::ISO8601 for example.
------ -------------------------------------------------------- Line libraries/Report/Processor/CertificateTransparency.php ------ -------------------------------------------------------- 116 Calling var_dump() is forbidden, use logger instead ------ --------------------------------------------------------
Sometimes, the method, the function, or the constant needs to be called or used once in your code, for example in a custom wrapper. You can use PHPStan's
ignoreErrors feature to ignore that one call:
ignoreErrors: - message: '#^Calling Redis::connect\(\) is forbidden, use our own Redis instead#' # Needed for the constructor path: application/libraries/Redis/Redis.php - message: '#^Calling print_r\(\) is forbidden, use logger instead#' # Used with $return = true paths: - application/libraries/Tls/Certificate.php - application/libraries/Tls/CertificateSigningRequest.php - application/libraries/Tls/PublicKey.php
You can also allow some previously disallowed calls and usages using the
allowIn configuration key, for example:
parameters: disallowedMethodCalls: - method: 'PotentiallyDangerous\Logger::log()' message: 'use our own logger instead' allowIn: - path/to/some/file-*.php - tests/*.test.php
The paths in
allowIn are relative to the config file location and support fnmatch() patterns.
To allow a previously disallowed method or function only when called from a different method or function in any file, use
parameters: disallowedMethodCalls: - method: 'PotentiallyDangerous\Logger::log()' message: 'use our own logger instead' allowInMethods: - Foo\Bar\Baz::method()
The function or method names support fnmatch() patterns.
You can also narrow down the allowed items when called with some parameters (doesn't apply to constants for obvious reasons). For example, you want to disallow calling
print_r() but want to allow
This can be done with optional
allowParamsAnywhere configuration keys:
parameters: disallowedMethodCalls: - method: 'PotentiallyDangerous\Logger::log()' message: 'use our own logger instead' allowIn: - path/to/some/file-*.php - tests/*.test.php allowParamsInAllowed: 1: 'foo' 2: true allowParamsAnywhere: 2: true
allowParamsInAllowed, calls will be allowed only when they are in one of the
allowIn paths, and are called with all parameters listed in
allowParamsAnywhere, calls are allowed when called with all parameters listed no matter in which file. In the example above, the
log() method will be disallowed unless called as:
allowParamsAnywhereAnyValue if you don't care about the parameter's value but want to make sure the parameter is passed.
Following the previous example:
parameters: disallowedMethodCalls: - method: 'PotentiallyDangerous\Logger::log()' message: 'use our own logger instead' allowIn: - path/to/some/file-*.php - tests/*.test.php allowParamsInAllowedAnyValue: - 2 allowParamsAnywhereAnyValue: - 1
means that you should use (
... means any value):
Such configuration only makes sense when both the parameters of
log() are optional. If they are required, omitting them would result in an error already detected by PHPStan itself.
Sometimes, it's handy to disallow a function or a method call only when a parameter matches but allow it otherwise. For example the
hash() function, it's fine using it with algorithm families like SHA-2 & SHA-3 (not for passwords though) but you'd like PHPStan to report when it's used with MD5 like
You can use
allowExceptParamsInAllowed config options to disallow only some calls:
parameters: disallowedFunctionCalls: - function: 'hash()' allowExceptCaseInsensitiveParams: 1: 'md5'
This will disallow
hash() call where the first parameter is
allowExceptCaseInsensitiveParams is used because the first parameter of
hash() is case-insensitive (so you can also use
'MD5', or even
'mD5' if you wish).
To disallow only exact matches, use
parameters: disallowedFunctionCalls: - function: 'foo()' allowExceptParams: 2: 'baz'
foo('bar', 'baz') but not
It's also possible to disallow functions and methods previously allowed by path (using
allowIn) or by function/method name (
allowInMethods) when they're called with specified parameters, and allow when called with any other parameter. This is done using the
allowExceptParamsInAllowed config option.
Take this example configuration:
parameters: disallowedFunctionCalls: - function: 'waldo()' allowIn: - 'views/*' allowExceptParamsInAllowed: 2: 'quux'
waldo() is disallowed, and allowed back again only when the file is in the
views/ subdirectory and
waldo() is called in the file with a 2nd parameter being the string
If you want to use this PHPStan extension without running any other PHPStan rules, you can use
phpstan.neon config file that looks like this (the
customRulesetUsed: true and the missing
level key are the important bits):
parameters: customRulesetUsed: true includes: - vendor/spaze/phpstan-disallowed-calls/extension.neon - vendor/spaze/phpstan-disallowed-calls/disallowed-dangerous-calls.neon - vendor/spaze/phpstan-disallowed-calls/disallowed-execution-calls.neon
If you want to contribute (awesome, thanks!), you should add/run tests for your contributions.
First install dev dependencies by running
composer install, then run PHPUnit tests with
composer test, see
composer.json. Tests are also run on GitHub with Actions on each push.
You can fix coding style issues automatically by running
There's a similar project with a slightly different configuration, created almost at the same time (just a few days difference): PHPStan Banned Code.
- For Nette Framework