The Validation Lifecycle

The Validation Lifecycle

Understanding the order of operations makes everything else click. A validator holds four pieces of state: the data, a rule queue, a list of optional fields, and the errors from the last run.

Queue → validate → read

use InitPHP\Validation\Validation;

$validation = new Validation(['age' => 'abc']);

$validation->rule('age', 'integer');   // 1. queue
$ok = $validation->validation();        // 2. validate  → false
$errors = $validation->getError();      // 3. read       → ["age must be an integer."]

rule() does not check anything — it only appends to the queue. validation() is what actually runs the checks.

What validation() does, in order

1. Clears the error list. Each run starts clean.
2. Runs every queued rule. For each rule it reads the field value from the data, runs the check, and appends a message on failure. Optional fields with no value are skipped.
3. Empties the rule queue and the optional list.
4. Returns true when no rule failed.

Because step 3 consumes the queue, the natural pattern is queue → validate → read, then repeat:

$validation->setData(['a' => 'x', 'b' => '5']);

$validation->rule('a', 'integer');
$validation->validation();   // checks only 'a' → false

$validation->rule('b', 'integer');
$validation->validation();   // checks only 'b' → true (the 'a' rule is gone)

If you expected the second run to re-check a, queue it again — rules are not sticky.

The data API

Method	Effect
new Validation($data)	Start with a data set.
setData($data)	Replace the whole data set.
mergeData($data)	Merge in values; existing keys are overwritten.
getData()	Read the current data set back.

$validation = new Validation(['a' => 1]);
$validation->mergeData(['b' => 2, 'a' => 3]);
$validation->getData(); // ['a' => 3, 'b' => 2]

validation() vs isValid()

• validation() runs the queue and returns the result.
• isValid() returns the result of the last run without re-running.

$validation->rule('a', 'integer')->validation(); // runs
$validation->isValid();                            // same answer, no re-run

Resetting with clear()

clear() throws away the queued rules, the optional flags and the errors — without validating. Registered custom rules, named patterns and the loaded locale are kept.

$validation->rule('a', 'integer');
$validation->clear();          // queue dropped
$validation->validation();      // nothing to check → true

What survives a run

State	Cleared by validation()	Cleared by clear()
Errors	Yes (at the start)	Yes
Rule queue	Yes (at the end)	Yes
Optional flags	Yes (at the end)	Yes
Data	No	No
Custom rules (extend)	No	No
Named patterns (pattern)	No	No
Loaded locale	No	No

So register your custom rules, patterns and locale once during setup, then loop over queue → validate → read as many times as you like.

Next

• Rules Reference — the full catalogue of checks.
• Optional Fields — how absent fields are handled.
• Error Messages — customizing what users see.