toolkit/packages/artifact/src/internal/download/download-artifact.ts

import fs from 'fs/promises'
import * as github from '@actions/github'
import * as core from '@actions/core'
import * as httpClient from '@actions/http-client'
import unzipper from 'unzipper'
import {
  DownloadArtifactOptions,
  DownloadArtifactResponse
} from '../shared/interfaces'
import {getUserAgentString} from '../shared/user-agent'
import {getGitHubWorkspaceDir} from '../shared/config'

const scrubQueryParameters = (url: string): string => {
  const parsed = new URL(url)
  parsed.search = ''
  return parsed.toString()
}

async function exists(path: string): Promise<boolean> {
  try {
    await fs.access(path)
    return true
  } catch (error) {
    if (error.code === 'ENOENT') {
      return false
    } else {
      throw error
    }
  }
}

async function streamExtract(url: string, directory: string): Promise<void> {
  const client = new httpClient.HttpClient(getUserAgentString())
  const response = await client.get(url)

  if (response.message.statusCode !== 200) {
    throw new Error(
      `Unexpected HTTP response from blob storage: ${response.message.statusCode} ${response.message.statusMessage}`
    )
  }

  return response.message.pipe(unzipper.Extract({path: directory})).promise()
}

export async function downloadArtifact(
  artifactId: number,
  repositoryOwner: string,
  repositoryName: string,
  token: string,
  options?: DownloadArtifactOptions
): Promise<DownloadArtifactResponse> {
  const downloadPath = options?.path || getGitHubWorkspaceDir()

  if (!(await exists(downloadPath))) {
    core.debug(
      `Artifact destination folder does not exist, creating: ${downloadPath}`
    )
    await fs.mkdir(downloadPath, {recursive: true})
  } else {
    core.debug(`Artifact destination folder already exists: ${downloadPath}`)
  }

  const api = github.getOctokit(token)

  core.info(
    `Downloading artifact '${artifactId}' from '${repositoryOwner}/${repositoryName}'`
  )

  const {headers, status} = await api.rest.actions.downloadArtifact({
    owner: repositoryOwner,
    repo: repositoryName,
    artifact_id: artifactId,
    archive_format: 'zip',
    request: {
      redirect: 'manual'
    }
  })

  if (status !== 302) {
    throw new Error(`Unable to download artifact. Unexpected status: ${status}`)
  }

  const {location} = headers
  if (!location) {
    throw new Error(`Unable to redirect to artifact download url`)
  }

  core.info(
    `Redirecting to blob download url: ${scrubQueryParameters(location)}`
  )

  try {
    core.info(`Starting download of artifact to: ${downloadPath}`)
    await streamExtract(location, downloadPath)
    core.info(`Artifact download completed successfully.`)
  } catch (error) {
    throw new Error(`Unable to download and extract artifact: ${error.message}`)
  }

  return {success: true, downloadPath}
}