EnvModel: Set env value from .env files and config value with default value

Overview

These tests validate nestjs-mod EnvModel: environment variable reading, required field validation, and DI value propagation into services.

What We Do And Verify

• We verify how configTransform and ConfigModel/ConfigModelProperty decorators process input parameters.

• We lock the validation contract and error shape expected by configuration consumers.

• We confirm that modules/services receive properly prepared configuration values.

• We explicitly validate the error contract: not only failure itself, but also error shape/content expected by module consumers.

• We confirm correct lifecycle behavior in test environment: initialization, dependency readiness, and graceful shutdown of app/modules.

GitHub Reference

• File: static-environments-model-with-boolean.spec.ts
• Line: 174

Setup Code

import {
import { DefaultTestNestApplicationCreate, DefaultTestNestApplicationInitializer } from '@nestjs-mod/testing';
import { join } from 'path';

describe('staticEnvironmentsModel', () => {

  // full test in the block below
});

Test Code

  it('set env value from .env files and config value with default value', async () => {
    const WEBHOOK_MODULE = 'WebhookModule';
    const WEBHOOK_ENV_PREFIX = 'webhook';

    let useGuardsFromEnv: boolean | undefined | null = undefined;
    let usePipesFromConfig: boolean | undefined | null = undefined;

    @EnvModel()
    class WebhookEnvironments {
      @EnvModelProperty({
        description: 'Use guards',
        default: 'true',
        transform: new BooleanTransformer(),
      })
      useGuards?: boolean | null;
    }

    @ConfigModel()
    class WebhookConfiguration {
      @ConfigModelProperty({
        description: 'Use pipes',
        default: true,
      })
      usePipes?: boolean | null;
    }

    const { WebhookModule } = createNestModule({
      moduleName: WEBHOOK_MODULE,
      moduleCategory: NestModuleCategory.feature,
      staticEnvironmentsModel: WebhookEnvironments,
      staticConfigurationModel: WebhookConfiguration,
      wrapForRootAsync: (asyncModuleOptions) => {
        if (!asyncModuleOptions) {
          asyncModuleOptions = {};
        }
        const FomatterClass = getFeatureDotEnvPropertyNameFormatter(WEBHOOK_ENV_PREFIX);
        Object.assign(asyncModuleOptions, {
          environmentsOptions: {
            propertyNameFormatters: [new FomatterClass()],
            name: WEBHOOK_ENV_PREFIX,
          },
        });

        return { asyncModuleOptions };
      },
      preWrapApplication: async (options) => {
        useGuardsFromEnv = options.current.staticEnvironments?.useGuards;
        usePipesFromConfig = options.current.staticConfiguration?.usePipes;
      },
    });

    delete process.env['SERVER_WEBHOOK_USE_GUARDS'];

    await bootstrapNestApplication({
      modules: {
        system: [
          ProjectUtils.forRoot({
            staticConfiguration: {
              applicationPackageJsonFile: join(__dirname, PACKAGE_JSON_FILE),
              packageJsonFile: join(__dirname, 'root-' + PACKAGE_JSON_FILE),
              nxProjectJsonFile: join(__dirname, PROJECT_JSON_FILE),
              envFile: join(__dirname, 'static-environments-model-with-boolean.env'),
            },
          }),
          DefaultTestNestApplicationCreate.forRoot(),
          DefaultTestNestApplicationInitializer.forRoot(),
        ],
        feature: [WebhookModule.forRoot()],
      },
    });

    expect(useGuardsFromEnv).toEqual(false);
    expect(usePipesFromConfig).toEqual(true);
  });