serverless-python-requirements/lib/pipenv.js

Serverless Python Requirements Plugin

const fse = require('fs-extra');
const path = require('path');
const spawn = require('child-process-ext/spawn');
const { EOL } = require('os');
const semver = require('semver');

const LEGACY_PIPENV_VERSION = '2022.8.5';

async function getPipenvVersion() {
  try {
    const res = await spawn('pipenv', ['--version'], {
      cwd: this.servicePath,
    });

    const stdoutBuffer =
      (res.stdoutBuffer && res.stdoutBuffer.toString().trim()) || '';

    const version = stdoutBuffer.split(' ')[2];

    if (semver.valid(version)) {
      return version;
    } else {
      throw new this.serverless.classes.Error(
        `Unable to parse pipenv version!`,
        'PYTHON_REQUIREMENTS_PIPENV_VERSION_ERROR'
      );
    }
  } catch (e) {
    const stderrBufferContent =
      (e.stderrBuffer && e.stderrBuffer.toString()) || '';

    if (stderrBufferContent.includes('command not found')) {
      throw new this.serverless.classes.Error(
        `pipenv not found! Install it according to the pipenv docs.`,
        'PYTHON_REQUIREMENTS_PIPENV_NOT_FOUND'
      );
    } else {
      throw e;
    }
  }
}

/**
 * pipenv install
 */
async function pipfileToRequirements() {
  if (
    !this.options.usePipenv ||
    !fse.existsSync(path.join(this.servicePath, 'Pipfile'))
  ) {
    return;
  }

  let generateRequirementsProgress;
  if (this.progress && this.log) {
    generateRequirementsProgress = this.progress.get(
      'python-generate-requirements-pipfile'
    );
    generateRequirementsProgress.update(
      'Generating requirements.txt from Pipfile'
    );
    this.log.info('Generating requirements.txt from Pipfile');
  } else {
    this.serverless.cli.log('Generating requirements.txt from Pipfile...');
  }

  try {
    // Get and validate pipenv version
    if (this.log) {
      this.log.info('Getting pipenv version');
    } else {
      this.serverless.cli.log('Getting pipenv version');
    }

    const pipenvVersion = await getPipenvVersion();
    let res;

    if (semver.gt(pipenvVersion, LEGACY_PIPENV_VERSION)) {
      // Using new pipenv syntax ( >= 2022.8.13)
      // Generate requirements from existing lock file.
      // See: https://pipenv.pypa.io/en/latest/advanced/#generating-a-requirements-txt
      try {
        res = await spawn('pipenv', ['requirements'], {
          cwd: this.servicePath,
        });
      } catch (e) {
        const stderrBufferContent =
          (e.stderrBuffer && e.stderrBuffer.toString()) || '';
        if (stderrBufferContent.includes('FileNotFoundError')) {
          // No previous Pipfile.lock, we will try to generate it here
          if (this.log) {
            this.log.warning(
              'No Pipfile.lock found! Review https://pipenv.pypa.io/en/latest/pipfile/ for recommendations.'
            );
          } else {
            this.serverless.cli.log(
              'WARNING: No Pipfile.lock found! Review https://pipenv.pypa.io/en/latest/pipfile/ for recommendations.'
            );
          }
          await spawn('pipenv', ['lock'], {
            cwd: this.servicePath,
          });
          res = await spawn('pipenv', ['requirements'], {
            cwd: this.servicePath,
          });
        } else {
          throw e;
        }
      }
    } else {
      // Falling back to legacy pipenv syntax
      res = await spawn(
        'pipenv',
        ['lock', '--requirements', '--keep-outdated'],
        {
          cwd: this.servicePath,
        }
      );
    }

    fse.ensureDirSync(path.join(this.servicePath, '.serverless'));
    fse.writeFileSync(
      path.join(this.servicePath, '.serverless/requirements.txt'),
      removeEditableFlagFromRequirementsString(res.stdoutBuffer)
    );
  } finally {
    generateRequirementsProgress && generateRequirementsProgress.remove();
  }
}

/**
 *
 * @param requirementBuffer
 * @returns Buffer with editable flags remove
 */
function removeEditableFlagFromRequirementsString(requirementBuffer) {
  const flagStr = '-e ';
  const lines = requirementBuffer.toString('utf8').split(EOL);
  for (let i = 0; i < lines.length; i++) {
    if (lines[i].startsWith(flagStr)) {
      lines[i] = lines[i].substring(flagStr.length);
    }
  }
  return Buffer.from(lines.join(EOL));
}

module.exports = { pipfileToRequirements };