dc/sas/mocks/sasjs/services/admin/exportdb.js

const nodePath = require('path')

let appLoc = nodePath.join(..._program.split('services')[0].split('/'))
const sasjsRoot = nodePath.resolve(weboutPath, '..', '..', '..')
const driveRoot = nodePath.resolve(sasjsRoot, 'drive')

eval(fs.readFileSync(nodePath.resolve(driveRoot, 'files', appLoc, 'services', 'dcMockUtils.js'), 'utf8'))

/**
 * Mock of services/admin/exportdb.sas - exports the DC library as DDL.
 *
 * The real service streams mp_ds2ddl output for every table in &DC_LIBREF, in
 * the requested flavour, and mp_lib2inserts appends the rows for the SAS and
 * PGSQL flavours.  This mock emits the DDL only - a basic, readable rendering
 * per flavour, enough to exercise the System screen's Export DC Library DDL
 * action end to end (the download headers, the filename, the flavour and the
 * optional schema).  It deliberately does not append INSERTs: the real service
 * does, but for a mock that would mean serialising the whole library's rows
 * (MPE_X_WIDE alone is 200,000 cells) for no extra test value.
 *
 * Params arrive from the URL the client opens:
 *   <serverUrl>/SASjsApi/stp/execute/?_program=<appLoc>/services/admin/exportdb
 *     &flavour=SAS|PGSQL|TSQL[&schema=<name>]
 * The schema box only applies to the DB flavours, and the client omits the
 * param entirely when it is blank, so both must be read defensively - an
 * unset URL param is an undeclared const here, not an empty string.
 */

const ddlFlavour = (typeof flavour === 'undefined' || !flavour)
    ? 'SAS'
    : String(flavour).toUpperCase()

const dcConf = loadDcSettings(driveRoot, appLoc)
const libref = dcConf.dcLibref
const dataDir = dcConf.dataDir

// if no schema param, the DC libref is used (as in exportdb.sas)
const ddlSchema = (typeof schema === 'undefined' || !schema)
    ? libref
    : String(schema)

// ─── Column types, per flavour ───────────────────────────────────────────────

function colType(col, flavour) {
    const isChar = String(col.type).toUpperCase() === 'C'
    const fmt = String(col.format || '').toUpperCase()
    const len = Number(col.length) || (isChar ? 1 : 8)

    if (flavour === 'SAS') {
        return isChar ? `char(${len})` : 'num'
    }

    // PGSQL and TSQL share the mapping; only the quoting differs.  The one type
    // that must not be shared is the datetime: T-SQL's TIMESTAMP is a deprecated
    // synonym for rowversion - a binary row version, not a datetime - so it maps
    // to DATETIME2 there.  DOUBLE PRECISION is a T-SQL synonym for float, so it
    // stays valid on both.
    if (isChar) return `VARCHAR(${len})`
    if (fmt.startsWith('DATETIME'))
        return flavour === 'TSQL' ? 'DATETIME2' : 'TIMESTAMP'
    if (fmt.startsWith('DATE')) return 'DATE'
    if (fmt.startsWith('TIME')) return 'TIME'
    return 'DOUBLE PRECISION'
}

function colRef(name, flavour) {
    if (flavour === 'PGSQL') return `"${name}"`
    if (flavour === 'TSQL') return `[${name}]`
    return name
}

function tableRef(table, flavour) {
    if (flavour === 'TSQL') return `[${ddlSchema}].[${table}]`
    return `${ddlSchema}.${table}`
}

// ─── Buskeys (for the unique index), from MPE_TABLES ─────────────────────────

const buskeys = {}
try {
    const reg = makeTableLoader(dataDir)('MPE_TABLES')
    for (const row of ((reg && reg.rows) || [])) {
        const dsn = String(colVal(row, 'DSN') || '').trim().toUpperCase()
        const buskey = String(colVal(row, 'BUSKEY') || '').trim()
        if (dsn && buskey) buskeys[dsn] = buskey
    }
} catch(err) { /* no MPE_TABLES - the DDL is still emitted, without indexes */ }

// ─── Build the DDL ───────────────────────────────────────────────────────────

const lines = []
const stamp = new Date().toISOString().replace('T', ':').substring(0, 19)
lines.push(`/* DDL generated by the Data Controller mock on ${stamp} */`)

if (ddlFlavour === 'PGSQL') {
    lines.push(`CREATE SCHEMA ${ddlSchema};`)
}

let tables = []
try {
    tables = fs.readdirSync(dataDir)
        .filter(f => f.endsWith('.json'))
        .map(f => {
            try {
                return JSON.parse(fs.readFileSync(nodePath.resolve(dataDir, f), {encoding:'utf8'}).toString())
            } catch(e) { return null }
        })
        .filter(t => t && t.name && Array.isArray(t.columns))
        .sort((a, b) => String(a.name).localeCompare(String(b.name)))
} catch(err) { /* nothing to export */ }

for (const table of tables) {
    const tableName = String(table.name).toUpperCase()
    const cols = table.columns.filter(c => String(c.name || '').trim() !== '')
    if (cols.length === 0) continue

    if (ddlFlavour === 'SAS') {
        lines.push(`/* SAS flavour DDL for ${libref}.${tableName} */`)
        lines.push(`create table ${tableRef(tableName, ddlFlavour)}(`)
    } else if (ddlFlavour === 'PGSQL') {
        lines.push(`/* Postgres Flavour DDL for ${libref}.${tableName} */`)
        lines.push(`CREATE TABLE ${tableRef(tableName, ddlFlavour)} (`)
    } else {
        lines.push(`/* TSQL Flavour DDL for ${libref}.${tableName} */`)
        lines.push(`create table ${tableRef(tableName, ddlFlavour)}(`)
    }

    cols.forEach((col, idx) => {
        const name = colRef(String(col.name).toUpperCase(), ddlFlavour)
        const prefix = idx === 0 ? '   ' : '  ,'
        lines.push(`${prefix}${name} ${colType(col, ddlFlavour)}`)
    })
    lines.push(');')

    // a unique index on the buskey, where MPE_TABLES declares one - SAS has no
    // equivalent in mp_ds2ddl output, so it is skipped for that flavour
    const buskey = buskeys[tableName]
    if (buskey && ddlFlavour !== 'SAS') {
        const keys = buskey.split(/[\s,]+/).filter(Boolean)
            .map(k => colRef(k.toUpperCase(), ddlFlavour))
        lines.push(
            `CREATE UNIQUE INDEX ${colRef(tableName + '_pk', ddlFlavour)} ON ` +
            `${tableRef(tableName, ddlFlavour)}(\n  ${keys.join('\n ,')}\n);`
        )
    }
    lines.push('')
}

// ─── Stream it back as a download, as mp_streamfile does ─────────────────────

/* exportdb.sas streams with %mp_streamfile(contenttype=TEXT
   ,outname=&dc_libref..ddl): an application/text attachment named
   <libref>.ddl, unquoted. Confirmed against the estate's own response
   (`content-type: application/text`,
   `content-disposition: attachment; filename=DC634301.ddl`). */
const filename = `${libref}.ddl`
fs.writeFile(
    _SASJS_WEBOUT_HEADERS,
    `Content-Type: application/text\nContent-disposition: attachment; filename=${filename}`,
    function (err) {
        if (err) throw err
    }
)

_webout = lines.join('\n') + '\n'