Symfony constraints

seampact/symfony writes a readonly class for each schema, with Symfony Validator attributes, and a generated constraint for each operation that checks the request. The bundle runs the constraint before your controller.

Used by: Symfony.

Set up

Nothing to add: the seampact/symfony target writes the classes. Its one option for validation is rules.

# seampact.config.yaml, under targets
  - id: tasks
    out: Tasks
    use: seampact/symfony
    api: tasks

What you get

A schema is a readonly class with #[Assert] attributes. For the CreateTask schema of the overview, in Schemas/CreateTask.php:

  public function __construct(
    #[Assert\NotNull, Assert\Length(min: 1, max: 200), \SensitiveParameter]
    public string $title,
    #[Assert\GreaterThanOrEqual(value: 0)]
    public ?int $effort,

A pattern is an Assert\Regex, but a uuid or date-time format has no attribute, so these attributes are not the whole contract.

Which checks run on a request

The request is not checked by these attributes. For each operation, Symfony/<Operation>InputConstraintValidator.php lists the members of the input as the contract declares them, and the bundle checks the decoded request against that list. This excerpt is from rules: seampact-consistent:

          'title' => new Member(
            JsonType::String,
            checks: new Checks(minLength: 1, maxLength: 200),
          ),
          'effort' => new Member(
            JsonType::Integer,
            presence: Presence::Optional,
            checks: new Checks(minimum: 0),
          ),

The attributes are for your own code. Validate an object you build before you send it elsewhere:

$violations = $validator->validate(new Task(taskId: $id, title: $title));

When a check fails

Each failure becomes an issue of the 400 body, named by the contract rule.

Native or consistent rules

native (the default) uses Symfony Validator’s own constraints where one exists. seampact-consistent gives the contract’s exact checks, equal on every target (Switch the validator).

Limits

The Symfony generator refuses by name a oneOf, a map schema, a file value and a property default (Generate fails).

Next

• Symfony.
• The 400 body: When a check fails.