@sap/eslint-plugin-cds/lib/rules/extension-restrictions.js

ESLint plugin including recommended SAP Cloud Application Programming model and environment rules

'use strict'

const cds = requireMtx()

const { dirname } = require('node:path')

const rule = module.exports = {
  meta: {
    docs: {
      description: 'Extensions must not violate restrictions set by the extended SaaS app.',
      category: 'Model Validation',
      recommended: true,
      url: 'https://cap.cloud.sap/docs/tools/cds-lint/rules/extension-restrictions',
    },
    hasSuggestions: false,
    type: 'problem',
    model: 'parsed'
  },
  mtxApi: () => {
    if (!cds) return // no mtxs lib installed
    if (!cds.xt?.linter) return // too old mtxs
    return cds.xt.linter
  },
  create (context) {
    if (!rule.mtxApi()) return // no mtxs lib installed

    return () => {
      const extModel = context.getModel()
      if (!extModel) return

      const base = baseModel(context)
      if (!base) return

      const file = context.getFilename()
      const findings = rule.mtxApi().lint(extModel, base.model, base.env)
      for (const finding of findings) {
        context.report({
          message: finding.message,
          node: context.getNode(finding.element),
          file
        })
      }
    }
  }
}

/**
 * @param {CDSRuleContext} context
 */
function baseModel (context) {
  let dir = context.getFilename()
  do {
    dir = dirname(dir)
    const projEnv = cds.env.for('cds', dir)
    if (!projEnv.extends) continue
    const files = cds.resolve(projEnv.extends, { root: dir }) // resolve local base model
    if (files?.length) {
      const model = cds.load(files, { sync: true })
      // env of SaaS app is needed for extension rules
      const env = cds.env.for('cds', dirname(files[0]))
      return { env, model }
    }
  } while (dir && dir !== cds.root && dir.length > 1)
}

/** @returns { import('@sap/cds/apis/cds') } */
function requireMtx () {
  const cds = require('@sap/cds')
  try {
    // eslint-disable-next-line
    const pkg = require.resolve('@sap/cds-mtxs', { paths: [cds.root, __dirname] })
    return require(pkg)
  } catch (e) {
    if (e.code !== 'MODULE_NOT_FOUND')
      throw e
  }
}