semaphore.ts

export class Semaphore {
  private concurrency: number
  private currentCount: number
  private queue: (() => void)[]

  constructor(concurrency: number) {
    this.concurrency = concurrency
    this.currentCount = 0
    this.queue = []
  }

  wait() {
    return new Promise<void>((resolve) => {
      const task = () => {
        this.currentCount++
        resolve()
      }

      if (this.currentCount < this.concurrency) {
        task()
      } else {
        this.queue.push(task)
      }
    })
  }

  release() {
    this.currentCount--

    if (this.queue.length > 0) {
      const nextTask = this.queue.shift()
      nextTask?.()
    }
  }
}

      
    const semaphore = new Semaphore(3)

    this.http = axios.create()

    this.http.interceptors.request.use((config) => {
      return semaphore.wait().then(() => {
        return config
      })
    })

    this.http.interceptors.response.use(
      (response) => {
        semaphore.release()
        return response
      },
      (error) => {
        semaphore.release()
        return Promise.reject(error)
      },
    )