error TS2353: Object literal may only specify known properties

[halohsu]

What did you do?

git clone

cd ui/react-app

npm i

npm run start

What did you expect to see?

Start the dev server.

What did you see instead? Under which circumstances?

npm run start                                                                                                                                       20:52:28

> @prometheus-io/alertmanager@0.0.0 start
> webpack serve --config webpack.dev.ts

[webpack-cli] Failed to load '/Users/halo/Code/alertmanager/ui/react-app/webpack.dev.ts' config
[webpack-cli] webpack.dev.ts:73:7 - error TS2353: Object literal may only specify known properties, and ''/api'' does not exist in type '(ProxyConfigArrayItem | ((req?: Request<ParamsDictionary, any, any, ParsedQs, Record<string, any>> | undefined, res?: Response<...> | undefined, next?: NextFunction | undefined) => ProxyConfigArrayItem))[]'.

73       '/api': 'http://localhost:9093',
         ~~~~~~

Environment

• System information:

  Darwin 24.1.0 arm64

• Alertmanager version:

alertmanager, version 0.28.0-rc.0 (branch: add-i18n, revision: f6b942cf9b3a503d59192eada300d2ad97cba82f)
  build user:       halo@HalodeMacBook-Pro.local
  build date:       20241108-12:37:33
  go version:       go1.23.1
  platform:         darwin/arm64
  tags:             netgo

• Prometheus version:

None

• Alertmanager configuration file:

route:
  group_by: ['alertname']
  group_wait: 30s
  group_interval: 5m
  repeat_interval: 1h
  receiver: 'web.hook'
receivers:
  - name: 'web.hook'
    webhook_configs:
      - url: 'http://127.0.0.1:5001/'
inhibit_rules:
  - source_match:
      severity: 'critical'
    target_match:
      severity: 'warning'
    equal: ['alertname', 'dev', 'instance']

• Prometheus configuration file:

• Logs: