@sap/cds-mtxs/srv/extensibility/compat/update.js

SAP Cloud Application Programming Model - Multitenancy library

const cds = require('@sap/cds')
module.exports = (srv) => {
    // mainly normalizing the input
    srv.before(['UPDATE', 'UPSERT'], 'Extensions', req => { // must be synchronous to be handled first
        const { csn: extension, i18n: bundles, csvs: csvData } = req.data

        // Validation of extension
        if (!extension) throw new cds.error({ message: 'Property "extension" is missing', code: 400 })
        if (Array.isArray(extension)) {
            if (!extension.length) throw new cds.error({ message: 'Property "extension" is empty', code: 400 })
        } else {
            const length = typeof extension === 'string' ? extension.length : Object.keys(extension).length
            if (!length) throw new cds.error({ message: 'Property "extension" is malformed', code: 400 })
        }

        // Merge extension to one extension csn
        let extCsn
        for (let ext of extension) {
            if (typeof ext === 'string') {
                if (!ext.length) throw new cds.error({ message: 'Missing extension', code: 400 })
                if (_isCSN(ext)) extCsn = _mergeCSN(JSON.parse(ext), extCsn)
                else try { extCsn = _mergeCSN(cds.parse.cdl(ext), extCsn) } catch (e) {
                    if (e.code === 'ERR_CDS_COMPILATION_FAILURE') throw new cds.error({ message: e.message, code: 422 })
                    else throw e
                }
            } else {
                if (!Object.keys(ext).length) throw new cds.error({ message: 'Missing extension', code: 400 })
                extCsn = _mergeCSN(ext, extCsn)
            }
        }
        if (extCsn.requires) delete extCsn.requires

        // merge i18n and csvs
        let csvs = {}
        const i18nJson = _mergeBundles(bundles) // convert to i18n.json
        if (csvData) csvs = _convertData(csvData)

        // REVISIT - overwrite existing parameters from API?
        req.data.csvs = csvs
        req.data.i18n = i18nJson
        req.data.csn = extCsn
    })

    const _isCSN = str => str.substring(0, 1) === '{'

    const _mergeCSN = function (extension, merged) {
        if (!merged) merged = { extensions: [], definitions: {} }
        if (extension.definitions) Object.assign(merged.definitions, extension.definitions)
        if (extension.extensions) merged.extensions.push(...extension.extensions)
        return merged
    }

    const _mergeBundles = function (bundles) {
        if (!Array.isArray(bundles)) return bundles ?? {}
        let mergedI18nJson = {}
        let fromJson = false
        bundles.forEach(file => {
            const key = file.name.match(/i18n_*(.*)\.properties/), lang = key?.[1]
            if (key) {
                if (fromJson) throw new cds.error({ message: `Mixed i18n file types not supported: i18n.json and ${file.name}`, code: 422 })
                mergedI18nJson[lang] = _toJson(file.content)
            } else if (file.name === 'i18n.json') {
                if (Object.entries(mergedI18nJson).length) throw new cds.error({ message: `Mixed i18n file types not supported: i18n.json and .properties`, code: 422 })
                try {
                    mergedI18nJson = JSON.parse(file.content)
                    fromJson = true
                } catch (e) {
                    throw new cds.error({ message: `Invalid JSON content in i18n.json: ${e.message}`, code: 422 })
                }
            }
        })
        return mergedI18nJson
    }

    const _convertData = function (resources) {
        const csvs = {}
        if (resources && Array.isArray(resources) && resources.length) {
            resources.forEach(file => {
                if (file.name.endsWith('.csv')) {
                    csvs[file.name] = file.content
                }
            })
        }
        return csvs
    }

    const _toJson = function (content) {
        const json = {}, splitted = content.split('\n')
        splitted.forEach(s => {
            const parts = s.split('=').map(s => s.trim()), [key, val] = parts
            if (parts.length === 2) json[key] = val
        })
        return json
    }
}