@sap/cds-dk/lib/build/plugins/featureToggles.js

Command line client and development toolkit for the SAP Cloud Application Programming Model

const path = require('path')
const cds = require('../../cds')
const { DEFAULT_CSN_FILE_NAME } = require('../constants')
const { getI18nDefaultFolder, filterFeaturePaths } = require('../util')

module.exports = class FeatureTogglesBuildPlugin extends require('./internal') {

    async compileAll(csn, destBase, destFts) {
        const sources = filterFeaturePaths(csn, this.task.options.model || this.task.src)
        const dictionary = { base: null, features: null }

        if (sources.features) {
            // create base model as the given CSN is containing all features
            dictionary.base = await cds.load(sources.base, this.options())
        } else {
            // CSN already represents the base model as no features exist
            dictionary.base = csn
        }
        // preserve @location as @source properties
        const csnStr = await this.compileToJson(dictionary.base, path.join(destBase, DEFAULT_CSN_FILE_NAME))
        const csnModel = JSON.parse(csnStr)
        csnModel.meta = csn.meta
        if (sources.features) {
            dictionary.features = await this._compileFeatures(sources.features, destBase, destFts, dictionary.base)
        }
        return { dictionary, sources }
    }

    async collectAllLanguageBundles(dictionary, paths, destBase, destFts) {
        const i18nFolder = getI18nDefaultFolder()
        const ftsName = path.dirname(cds.env.features.folders || 'fts/*')
        // create language bundle for base model
        await this.collectLanguageBundles(dictionary.base, path.join(destBase, i18nFolder))

        if (dictionary.features) {
            // create language bundles for all features
            const featureBundleTasks = Object.keys(dictionary.features).map(async ftName => {
                // attach the sources information for i18n location reference
                dictionary.features[ftName]['$sources'] = paths.features[ftName]
                await this.collectLanguageBundles(dictionary.features[ftName], path.join(destFts, ftsName, ftName, i18nFolder))
            })
            await Promise.all(featureBundleTasks)
        }
    }

    async _compileFeatures(ftsPaths, destBase, destFts, baseCsn) {
        if (!ftsPaths) {
            return
        }
        const features = {}
        const options = { ...this.options(), flavor: 'parsed' }
        const ftsName = path.dirname(cds.env.features.folders || 'fts/*')

        // create feature models
        await Promise.all(Object.keys(ftsPaths).map(async ftName => {
            const ftCsn = await cds.load(ftsPaths[ftName], options)
            const ftPath = path.join(destFts, ftsName, ftName)

            // replace require paths by base model path to ensure precedence of feature annotations
            // see https://pages.github.tools.sap/cap/docs/cds/compiler-messages#anno-duplicate-unrelated-layer
            ftCsn.requires = [path.join(path.relative(ftPath, destBase), DEFAULT_CSN_FILE_NAME).replace(/\\/g, '/')]

            await this.compileToJson(ftCsn, path.join(ftPath, DEFAULT_CSN_FILE_NAME))
            this._validateFeature(ftCsn, baseCsn)
            features[ftName] = ftCsn
        }))
        return features
    }

    _validateFeature(ftCsn, baseCsn) {
        // features must not have other dependencies than base model dependencies - cross feature dependencies are not supported
        // assuming only core compiler options are relevant for validation scenario
        cds.compiler.compileSources({ [ftCsn.requires[0]]: baseCsn, 'feature.csn': ftCsn }, { ...super.options(), ...cds.env.cdsc ?? {} })
    }
}