rsnext/test/lib/next-modes/next-start.ts

import path from 'path'
import fs from 'fs-extra'
import { NextInstance } from './base'
import spawn from 'cross-spawn'
import { Span } from 'next/src/trace'

export class NextStartInstance extends NextInstance {
  private _buildId: string
  private _cliOutput: string = ''
  private spawnOpts: import('child_process').SpawnOptions

  public get buildId() {
    return this._buildId
  }

  public get cliOutput() {
    return this._cliOutput
  }

  public async setup(parentSpan: Span) {
    await super.createTestDir({ parentSpan })
  }

  private handleStdio = (childProcess) => {
    childProcess.stdout.on('data', (chunk) => {
      const msg = chunk.toString()
      if (!process.env.CI) process.stdout.write(chunk)
      this._cliOutput += msg
      this.emit('stdout', [msg])
    })
    childProcess.stderr.on('data', (chunk) => {
      const msg = chunk.toString()
      if (!process.env.CI) process.stderr.write(chunk)
      this._cliOutput += msg
      this.emit('stderr', [msg])
    })
  }

  public async start() {
    if (this.childProcess) {
      throw new Error('next already started')
    }
    this._cliOutput = ''
    this.spawnOpts = {
      cwd: this.testDir,
      stdio: ['ignore', 'pipe', 'pipe'],
      shell: false,
      env: {
        ...process.env,
        ...this.env,
        NODE_ENV: '' as any,
        PORT: this.forcedPort || '0',
        __NEXT_TEST_MODE: 'e2e',
      },
    }

    let buildArgs = ['yarn', 'next', 'build']
    let startArgs = ['yarn', 'next', 'start']

    if (this.buildCommand) {
      buildArgs = this.buildCommand.split(' ')
    }
    if (this.startCommand) {
      startArgs = this.startCommand.split(' ')
    }

    console.log('running', buildArgs.join(' '))
    await new Promise<void>((resolve, reject) => {
      try {
        this.childProcess = spawn(
          buildArgs[0],
          buildArgs.slice(1),
          this.spawnOpts
        )
        this.handleStdio(this.childProcess)
        this.childProcess.on('exit', (code, signal) => {
          this.childProcess = null
          if (code || signal)
            reject(
              new Error(`next build failed with code/signal ${code || signal}`)
            )
          else resolve()
        })
      } catch (err) {
        require('console').error(`Failed to run ${buildArgs.join(' ')}`, err)
        setTimeout(() => process.exit(1), 0)
      }
    })

    this._buildId = (
      await fs
        .readFile(
          path.join(
            this.testDir,
            this.nextConfig?.distDir || '.next',
            'BUILD_ID'
          ),
          'utf8'
        )
        .catch(() => '')
    ).trim()

    console.log('running', startArgs.join(' '))
    await new Promise<void>((resolve) => {
      try {
        this.childProcess = spawn(
          startArgs[0],
          startArgs.slice(1),
          this.spawnOpts
        )
        this.handleStdio(this.childProcess)

        this.childProcess.on('close', (code, signal) => {
          if (this.isStopping) return
          if (code || signal) {
            require('console').error(
              `next start exited unexpectedly with code/signal ${
                code || signal
              }`
            )
          }
        })

        const readyCb = (msg) => {
          if (msg.includes('started server on') && msg.includes('url:')) {
            this._url = msg.split('url: ').pop().split(/\s/)[0].trim()
            this._parsedUrl = new URL(this._url)
            this.off('stdout', readyCb)
            resolve()
          }
        }
        this.on('stdout', readyCb)
      } catch (err) {
        require('console').error(`Failed to run ${startArgs.join(' ')}`, err)
        setTimeout(() => process.exit(1), 0)
      }
    })
  }

  public async build() {
    this.spawnOpts = {
      cwd: this.testDir,
      stdio: ['ignore', 'pipe', 'pipe'],
      shell: false,
      env: {
        ...process.env,
        ...this.env,
        NODE_ENV: '' as any,
        PORT: this.forcedPort || '0',
        __NEXT_TEST_MODE: 'e2e',
      },
    }
    return new Promise((resolve) => {
      const curOutput = this._cliOutput.length
      const exportArgs = ['pnpm', 'next', 'build']

      if (this.childProcess) {
        throw new Error(
          `can not run export while server is running, use next.stop() first`
        )
      }

      console.log('running', exportArgs.join(' '))

      this.childProcess = spawn(
        exportArgs[0],
        exportArgs.slice(1),
        this.spawnOpts
      )
      this.handleStdio(this.childProcess)

      this.childProcess.on('exit', (code, signal) => {
        this.childProcess = undefined
        resolve({
          exitCode: signal || code,
          cliOutput: this.cliOutput.slice(curOutput),
        })
      })
    })
  }

  public async export(...[args]: Parameters<NextInstance['export']>) {
    return new Promise((resolve) => {
      const curOutput = this._cliOutput.length
      const exportArgs = ['pnpm', 'next', 'export']

      if (args?.outdir) exportArgs.push('--outdir', args.outdir)

      if (this.childProcess) {
        throw new Error(
          `can not run export while server is running, use next.stop() first`
        )
      }
      console.log('running', exportArgs.join(' '))

      this.childProcess = spawn(
        exportArgs[0],
        exportArgs.slice(1),
        this.spawnOpts
      )
      this.handleStdio(this.childProcess)

      this.childProcess.on('exit', (code, signal) => {
        this.childProcess = undefined
        resolve({
          exitCode: signal || code,
          cliOutput: this.cliOutput.slice(curOutput),
        })
      })
    })
  }
}