Custom resolver won't load into i18n module

[BobbiSixkiller]

Hi I'd like to reopen this issue because with current version "^9.2.1" I can not successfuly import custom Resolver. I'm testing this the same way as OP. It doesn't run the console log in resolve method so I guess the resolver does not load to i18n service at all.

custom.resolver.ts

import { Injectable, ExecutionContext } from '@nestjs/common';
import { I18nResolver, I18nResolverOptions } from 'nestjs-i18n';
import { isRabbitContext } from '@golevelup/nestjs-rabbitmq';

@Injectable()
export class CustomResolver implements I18nResolver {
  constructor(@I18nResolverOptions() private keys: string[]) {}

  resolve(context: ExecutionContext) {
    let lang: string;
    console.log('HAJZLE');
    console.log(context);

    switch (context.getType() as string) {
      case 'rmq':
        const message = context.getArgs()[0];
        console.log(message);
    }

    return this.keys[1];
  }
}

email.module.ts

import { Module } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { MailerModule } from '@nestjs-modules/mailer';
import { I18nModule, I18nService } from 'nestjs-i18n';
import { HandlebarsAdapter } from '@nestjs-modules/mailer/dist/adapters/handlebars.adapter';
import { join } from 'path';
import { EmailService } from './email.service';
import { CustomResolver } from 'src/email/custom.resolver';

@Module({
  imports: [
    I18nModule.forRootAsync({
      useFactory() {
        return {
          fallbackLanguage: 'sk',
          loaderOptions: {
            path: join(__dirname, '/locales/'),
            watch: true,
          },
        };
      },
      resolvers: [{ use: CustomResolver, options: ['en', 'sk'] }],
    }),
    MailerModule.forRootAsync({
      useFactory(config: ConfigService, i18n: I18nService) {
        return {
          transport: {
            host: 'smtp.mailtrap.io',
            secure: false,
            auth: {
              user: 'dfe6cc63fd2380',
              pass: 'b7e520dba14a13',
            },
          },
          defaults: {
            from: `"No Reply" <${config.get<string>('EMAIL_FROM')}>`,
          },
          template: {
            dir: join(__dirname, '/templates/'),
            adapter: new HandlebarsAdapter({ t: i18n.hbsHelper }),
            options: {
              strict: true,
            },
          },
        };
      },
      inject: [ConfigService, I18nService],
    }),
  ],
  providers: [EmailService],
})
export class EmailModule {}

thanks for any help in advance!

[toonvanstrijp]

@BobbiSixkiller can you send a small repo containing the issue? A zip is enough :)

[BobbiSixkiller]

First of all thanks a lot @toonvanstrijp for such a fast reply:) here's the link. Basically the idea is that the whole nestjs app consists of mail module and rmq module and responds to an incoming message from rmq by sending email. The email itself has to be localized and I wanted to use the custom resolver to resolve proper locale that comes in with the message object.

[Tomas2D]

Having same issue, temporary downgraded to 9.1.10

[toonvanstrijp]

@BobbiSixkiller sorry for the late reply, do you still need help with this issue?

[BobbiSixkiller]

@toonvanstrijp yes, I even tried to downgrade the version as mentioned by @Tomas2D but still no luck. Right now I set the locale when sending the mail via MailerService sendmail method's context property. Resolving the locale inside custom resolver based on incoming RMQ message would be way more ellegant in my opion. Thank's again for coming back to me btw.

[toonvanstrijp]

@BobbiSixkiller feel free to make a PR to support this. I've not worked with NestJS and RMQ before. So any help is welcome!

[B0ER]

@BobbiSixkiller, tried to reproduce, just took sample/simple project with nestjs-i18n@9.2.3 and got correct logs and response.
(switch operator to rmq was commented)

If you could, it will be better to have attached package-lock, Interesting in nestjs packages' versions and nestjs-i18n
Also would be great to have tsconfig and ts version

[agilesoftgrowth]

example of custom resolver for rabbitmq

import { ExecutionContext, Injectable, Logger } from '@nestjs/common';

@Injectable()
export default class AmqpResolver implements I18nResolver {
  private logger = new Logger('I18nService');

  constructor(
    @I18nResolverOptions()
    private keys: string[] = ['x-lang'],
  ) {}

  resolve(context: ExecutionContext) {
    const ctx = context.switchToRpc().getContext();
    const message = ctx.getMessage();

    let lang: string;

    if (message) {
      for (const key of this.keys) {
        if (message?.properties?.headers[key] !== undefined) {
          this.logger.log(
            `Detected header '${key}' with value: '${message.properties.headers[key]}'`,
          );
          lang = message.properties.headers[key];
          break;
        }
      }
    }

    if (!lang) {
      this.logger.warn(
        `No language detected. None of the following headers were found in message: ${this.keys.join(', ')}`,
      );
    }

    return lang;
  }
}

and app.module.ts

import { Module } from '@nestjs/common';
import config from './config';
import { ConfigModule, ConfigService } from '@nestjs/config';
import { EmailController } from './controller/email.controller';
import { MailerModule } from '@nestjs-modules/mailer';
import { HandlebarsAdapter } from '@nestjs-modules/mailer/dist/adapters/handlebars.adapter';
import { join } from 'path';
import { EmailService } from './services/email.service';
import { I18nModule, I18nService } from 'nestjs-i18n';
import { AmqpResolver } from './common/resolver';

@Module({
  imports: [
    ConfigModule.forRoot({
      load: config,
      isGlobal: true,
      cache: true,
      envFilePath: ['.env', '.env.local'],
      expandVariables: true,
    }),
    I18nModule.forRootAsync({
      useFactory: () => ({
        disableMiddleware: false,
        fallbackLanguage: 'en',
        viewEngine: 'hbs',
        loaderOptions: {
          path: join(__dirname, '/assets/i18n/'),
        },
      }),
      resolvers: [new AmqpResolver()],
    }),
    MailerModule.forRootAsync({
      inject: [ConfigService, I18nService],
      useFactory: (configs: ConfigService, i18n: I18nService) => {
        console.log(i18n.getTranslations());
        return {
          transport: {
            host: configs.get('smtp.host'),
            port: configs.get('smtp.port'),
            secure: configs.get('smtp.InsecureSkipVerify'),
            auth: {
              user: configs.get('smtp.user'),
              pass: configs.get('smtp.password'),
            },
          },
          template: {
            dir: join(__dirname, 'assets/template'),
            adapter: new HandlebarsAdapter({ t: i18n.hbsHelper }),
            options: {
              strict: true,
            },
          },
        };
      },
    }),
  ],
  controllers: [EmailController],
  providers: [EmailService],
})
export class AppModule {}