Schemas

A schema (ConfigSchema) lists the fields of a resource: their keys, types, labels, help texts, constraints, apply modes and visibility rules. Your provider returns it from describe().

Create fields with the static factories of ConfigField and collect them with ConfigSchema.of(...) or ConfigSchema.builder(). The demo builds its schema once, together with the SectionMapper that maps it to config.yml:

public final class VoucherConfigProvider implements ConfigProvider {
    private final SectionMapper mapper = VoucherSchema.mapper();

    @Override
    public ConfigSchema describe() {
        return mapper.schema();
    }
}

// VoucherSchema
public static SectionMapper mapper() {
    return SectionMapper.builder(create()).keyedSection("vouchers").build();
}

The full VoucherSchema.create() excerpt is on describe() and read().

What the schema drivesCopy Anchor Link

• The editor. Every control, section, list and hint is generated from the schema; there is no plugin-specific web code. Top-level objects are editor sections.
• The bridge's checks. Before your validate runs, the bridge checks the submitted values against the schema: types, ranges, patterns, choices, required values, list sizes, duplicate keys and so on. See what the bridge checks.
• Change summaries. Labels build change labels such as Vouchers › Daily Reward › Cooldown, and itemKey lets the bridge report edits, moves, additions and removals of list items precisely.
• Apply modes. Fields declared restartRequired() are reported as waiting for a restart.

Only declared keys are sentCopy Anchor Link

Only declared keys are ever sent to the editor. Everything else in your file (config-version, a metrics section, voucher lore) stays private and must be preserved by your apply.

Built and checked eagerlyCopy Anchor Link

Builders validate eagerly and throw SchemaException (an IllegalArgumentException) for inconsistent definitions, so a broken schema fails at describe() time in your own tests. Build your schema in a test.

describe() is called whenever the editor opens the resource and before every validate and apply, so a schema can depend on runtime data, for example choices built from loaded content.

The schema reference lists every builder.