chainpoint-cli/lib/export.js

Chainpoint CLI

/* Copyright 2017 Tierion
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *     http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

const utils = require('./utils.js')
const storage = require('./storage.js')
const cpb = require('chainpoint-binary')
const updateCmd = require('./update.js')
const OutputBuilder = require('./output-builder.js')

// The time until a proof expires from storage
const PROOF_EXPIRE_MINUTES = 1440

async function executeAsync(yargs, argv) {
  let output = new OutputBuilder('export')
  // honor the quiet directive if set
  let quiet = argv.quiet || false
  // honor the json directive if set
  let json = argv.json || false

  // check for valid argument value
  let proofId = argv._[1]
  let isValidProofId = utils.proofIdIsValid(proofId)
  if (!isValidProofId) {
    output.addErrorResult({
      proof_id: proofId,
      message: `missing or invalid proof_id`
    })
    output.display(quiet, json)
    return
  }
  // parameters are valid, open storage and process export
  try {
    let hashDb = await storage.connectAsync()
    let hashItem = await hashDb.findOneAsync({ _id: proofId }, { _id: 1, gatewayUri: 1 })
    if (!hashItem) {
      throw new Error('proof_id not found')
    }

    let targetGatewayUri = hashItem.gatewayUri || null
    if (!targetGatewayUri) {
      throw new Error('gateway_uri for proof_id not found')
    }

    // make sure proof hasnt expired
    if (!utils.proofIdExpired(PROOF_EXPIRE_MINUTES, proofId)) {
      let proofHandles = [{ uri: targetGatewayUri, proofId }]
      await updateCmd.updateHashesByProofIdAsync(hashDb, proofHandles)
    }

    // retrieve the proof by proof_id
    hashItem = await hashDb.findOneAsync({ _id: proofId })
    if (!hashItem || !hashItem.proof) throw new Error('proof data not found')

    // save file
    let exportAsJSON = !argv.binary
    let filename = `${hashItem._id}.chp${exportAsJSON ? '.json' : ''}`
    let path = `./${filename}`
    let proofObj = null
    try {
      proofObj = cpb.binaryToObjectSync(hashItem.proof)
    } catch (err) {
      throw new Error('bad proof data')
    }
    let writeSuccess = false
    if (exportAsJSON) {
      // save the proof as a JSON string with extension .chp.json
      let proofJSON = JSON.stringify(proofObj, null, 2)
      writeSuccess = utils.writeFile(path, proofJSON)
    } else {
      // save the proof as binary data with extension .chp
      let proofBin = cpb.objectToBinarySync(proofObj)
      writeSuccess = utils.writeFile(path, proofBin)
    }
    if (!writeSuccess) throw new Error('cannot write file')

    output.addSuccessResult({
      proof_id: proofId,
      filename: filename,
      message: `exported`
    })
    output.display(quiet, json)
  } catch (error) {
    output.addErrorResult({
      proof_id: proofId,
      message: `${error.message}`
    })
    output.display(quiet, json)
  }
}

module.exports = {
  executeAsync: executeAsync
}