generateWhiteLabelSource function

String generateWhiteLabelSource(WhiteLabelConfig config, String tenantId, { String? envName, })

Generates the lib/white_label.g.dart source text for config's tenant tenantId — a pure function (no file I/O) so it's directly testable; see writeGeneratedFile for the CLI's actual file-writing entry point.

envName selects which of TenantConfig.environments to bake in — same tenant/brand, different runtime config (typically just api_base_url) per deploy target (staging, production, ...). null (the default) uses TenantConfig.environment, the tenant's single default/fallback — unchanged behavior for a tenant that never declared environments: at all. Throws ArgumentError if envName is non-null but not declared for this tenant (see TenantConfig.resolveEnvironment) — never silently falls back to the default environment, since that would mean a "staging" build shipping production's API URL without any indication it happened.

Implementation

String generateWhiteLabelSource(
  WhiteLabelConfig config,
  String tenantId, {
  String? envName,
}) {
  final List<String> tenantIds = config.tenants.keys.toList()..sort();
  final TenantConfig selected = config[tenantId];
  final TenantEnvironment resolvedEnvironment = selected.resolveEnvironment(
    envName,
  );
  final String envSuffix = envName == null ? '' : ' (environment: "$envName")';

  final buffer = StringBuffer()
    ..writeln('// GENERATED CODE - DO NOT MODIFY BY HAND')
    ..writeln('//')
    ..writeln('// Generated by `dart run white_label_kit:generate` from')
    ..writeln(
      '// white_label.yaml for tenant "$tenantId"$envSuffix — re-run after',
    )
    ..writeln('// editing white_label.yaml or changing tenants.')
    ..writeln('//')
    ..writeln('// SECURITY: only "$tenantId"\'s data is in this file — see')
    ..writeln("// lib/src/generation/dart_config_generator.dart's doc")
    ..writeln('// comment for why that matters.')
    ..writeln()
    ..writeln("import 'package:white_label_kit/white_label_kit.dart';")
    ..writeln()
    ..writeln('/// The `default_tenant` declared in white_label.yaml.')
    ..writeln(
      'const String whiteLabelDefaultTenant = ${_dartString(config.defaultTenant)};',
    )
    ..writeln()
    ..writeln(
      '/// Every tenant id declared in white_label.yaml, sorted — NAMES\n'
      '/// only, not their config. Fine to ship in every build; use this\n'
      '/// for things like a tenant picker in an internal/dev build, not\n'
      "/// for reading another tenant's actual data (which isn't here).",
    )
    ..writeln(
      'const List<String> whiteLabelTenantIds = ${_dartStringList(tenantIds)};',
    )
    ..writeln()
    ..writeln(
      "/// The environment name this build was generated for (\"staging\",\n"
      '/// "production", ...), or an empty string if `--env` wasn\'t passed\n'
      "/// (the tenant's default/fallback environment was used).",
    )
    ..writeln(
      'const String whiteLabelEnvironmentName = ${_dartString(envName ?? '')};',
    )
    ..writeln()
    ..writeln(
      "/// This build's tenant, resolved when `generate` last ran (see\n"
      "/// resolveGeneratorTenantId) — the ONLY tenant's data in this file.",
    )
    ..writeln(
      'const WhiteLabelRuntime whiteLabelRuntime = '
      '${_runtimeLiteral(selected, resolvedEnvironment)};',
    );

  return buffer.toString();
}