Generating from an audit

StatementGenerator writes the next version of a statement from the latest audit of the content, the reports phil/accessibility-check wrote for its pages.

use Phil\AccessibilityCheck\AccessibilityChecker;
use Phil\AccessibilityCheck\Severity;
use Phil\AccessibilityStatement\Audit\AuditedPage;
use Phil\AccessibilityStatement\Audit\AuditResult;
use Phil\AccessibilityStatement\EvaluationMethod;
use Phil\AccessibilityStatement\StatementGenerator;

$checker = new AccessibilityChecker();
$audit = new AuditResult(new DateTimeImmutable(), [
    new AuditedPage('/', $checker->checkHtml($home)),
    new AuditedPage('/events', $checker->checkHtml($events)),
], EvaluationMethod::Automated, reportUrl: '/accessibility/audit.html');

$next = new StatementGenerator(Severity::Error)->generate($current, $audit, new DateTimeImmutable());

What the next version holds

• Everything an audit does not know comes from the current version: the target, the feedback contact, the alternatives, the scope, the enforcement procedure, the organisation.
• The non-conformities written by hand (fromAudit false) are kept as they are, first.
• The non-conformities of the previous audit are replaced by those of this one: one for each success criterion of the target that a finding of the minimum severity or graver fails — Error by default —, in the order of the criteria, with the number of findings across the pages as occurrences, and fromAudit true.
• A criterion the previous audit found already keeps what was written of it: its reason, description, alternative and date of fix. A criterion the audit no longer finds is lifted.
• A criterion that a non-conformity written by hand names is left to it. A criterion outside the target — a finding of a level AAA criterion under an AA target — is not a non-conformity of the statement.
• The status is the one the non-conformities support (ConformanceStatus::derive()).
• The evaluation is the audit's: its moment, its method, the number of its pages and its report.
• The version is one more than the current one, unless generate() is given another number.

An automated check does not see every barrier: a statement generated from one says EvaluationMethod::Automated, and the non-conformities people found stay in it, written by hand.

Reading reports back

An audit run elsewhere — by phil:accessibility:check --format=json, or by an application that stores json_encode($report) — is read back by Audit\ReportReader:

use Phil\AccessibilityStatement\Audit\ReportReader;

$report = new ReportReader()->fromJson(file_get_contents('var/accessibility/home.json'));

It reads the outcome of each rule and each finding: its rule, criterion, severity, message key and parameters, and location. The text of a message is written again from the catalogue of phil/accessibility-check, in the locale of the report. A report larger than 5 MiB (or the size given to the constructor), deeper than a report is, or not shaped as one, is refused with an InvalidReport; at most 50 000 rules and 50 000 findings are read.

Where the audit comes from

Contract\AuditSource is the port an application implements to give the latest audit: a directory of reports, a table, a service that checks the pages of the site. latest() returns an AuditResult, or null when there is none yet. phil/accessibility-statement-bundle gives one that reads a directory of JSON reports.