Function validateBuildSteps

server/src/aws/validateBuildSteps.ts:5–38

(taskFamilyDirectory: string, buildStepsBeforeValidation: BuildStep[])

import { BuildStep, FileBuildStep, ShellBuildStep } from '../Driver'

export async function validateBuildSteps(taskFamilyDirectory: string, buildStepsBeforeValidation: BuildStep[]) {
  return await Promise.all(
    buildStepsBeforeValidation.map(async buildStep => {
      switch (buildStep.type) {
        case 'shell':
          return ShellBuildStep.parse(buildStep)
        case 'file': {
          const { source, destination } = FileBuildStep.parse(buildStep)

          const taskFamilyDirectoryRealPath = await realpath(taskFamilyDirectory)
          // realpath expands symlinks, so we don't have to worry about symlinks pointing to files outside the task family directory.
          const sourceRealPath = await realpath(join(taskFamilyDirectory, source))
          if (!sourceRealPath.startsWith(taskFamilyDirectoryRealPath)) {
            throw new Error(
              `Path to copy ${source}'s realpath is ${sourceRealPath}, which is not within the task family directory ${taskFamilyDirectory}.`,
            )
          }

          return {
            type: 'file' as const,
            sourceWithinTaskFamilyDirectory: source,
            destination,
          }
        }
        default:
          // This function checks that buildStep is of type never, to ensure that getPackerTemplate explicitly validates all types
          // of build steps.
          ;((val: never) => {
            throw new Error(`Unexpected value for buildStep.type. buildStep: ${JSON.stringify(val)}`)
          })(buildStep)
      }
    }),
  )
}