@sap/xsodata/lib/configuration.js

Expose data from a HANA database as OData V2 service with help of .xsodata files.

'use strict';
/**
 * Configuration.
 * @module configuration
 */

exports.modes = {
    development: "development",
    productive: "productive"
};


/**
 * Exposed in index.js and used by xsjs or other application to set options for a hole OData handler
 * @param init
 * @constructor
 */
exports.HandlerOptions = function HandlerOptions(init) {

    /**
     * serviceConfiguration may be a directory containing *.xsodata files (the directory name MUST NOT end with ".xsodata")
     *    Usage: When pathPrefix is "/sub1/sub2" and serviceConfiguration is directory "./services" then the request to
     *    url "/sub1/sub2/test.xsodata" will be processed by the odata handler using the file
     *    "test.xsodata" from the directory "./services" and the odata service url will be "/sub1/sub2/test.xsodata"

     * serviceConfiguration may be a full qualified filename (the file name MUST end with ".xsodata")
     *    Sample: When using pathPrefix "/sub1/sub2/" as serviceConfiguration is "./services/my_service.xsodata" then the request to
     *    url "/sub1/sub2" will be processed by the odata handler using the file
     *    "./services/my_service.xsodata" and the odata service url will be "/sub1/sub2"
     * @type {string}
     */
    this.serviceConfiguration = init.serviceConfiguration;

    /**
     * Default schema which will set on the HDB connection if not null
     * @type {string|null}
     */
    this.defaultSchema = init.defaultSchema || null;

    /**
     * Settings to open a new database connection via HDB. A new connection is only open if the handlers processRequest method
     * is called WITHOUT an connected database connection.
     * @type {Object} Passed to HDB createClient
     */
    this.dbConfiguration = init.dbConfiguration || null;

    /**
     * Define db driver to be used if dbConfiguration parameters are set.
     * Possible settings are 'hana-client' or 'hdb'
     * Default is 'hana-client'
     */
    this.dbDriver = init.dbDriver || '@sap/hana-client';

    /**
     * Logger Object with methods 'trace','debug','info','warn','error','fatal'. Each of them having a string as input parameter
     * For example a Winston logger instance is suitable
     * @type {logger|null}
     */
    this.logger = init.logger || null;

    check(this);
};


/**
 * RequestOptions encapsulate all options witch can be set on a per request basis
 * Exposed in index.js and used by xsjs or other application when calling "processRequest"
 * @class
 * @param init
 * @param {exports.modes.productive|exports.modes.development} [init.mode=exports.modes.productive] - Sets the operation mode. Must be exports.modes.productive or exports.modes.development
 * @param [init.uriPrefix] - if any kind of routing strips parts of the url, this part can be added here to
 *                       create correct embedded urls
 * @constructor
 */
exports.RequestOptions = function RequestOptions(init) {
    /**
     * If the xsodata handler is used within frameworks which modify the request url(e.g. express)
     * is may be required inform the xsodata handler about the removed parts.
     * The xsodata module adds this prefix before the service root when building the baseurl
     */
    this.uriPrefix = init.uriPrefix;


    this.dbClient = init.dbClient || null;

    /** Function to open the db connection lazy
     * The functions first parameter contains the dbConfiguration passed via HandlerOptions.dbConfiguration,
     * the second parameter is a callback function with the signature (error, dbClient).
     *
     * Sample:
     * RequestOptions.dbOpenCB = function openConnection(dbConfiguration, cb) {
     *     var client = hdb.createClient(dbConfiguration);
     *     client.connect(function (err) {
     *         return cb(err,client);
     *     });
     * }
     * ...
     * @type {function}
     */

    this.dbOpenCB = init.dbOpenCB || null;

    /** Function to close if the db connection has been opened lazy
     * The functions first parameter contains the dbClient
     * the second parameter is a callback function without parameters.
     *
     * Sample:
     * RequestOptions.dbCloseDB = function(dbClient, cb) {
     *     dbClient.end();
     *     return cb();
     * }
     * ...
     * @type {function}
     */
    this.dbCloseCB = init.dbCloseCB || null;

    /**
     * Function used to call a application function obtained from the moduleLoader.
     * The function used because some environment required special call handling, e.g. to process the
     * application function synchronous.
     * @type {null|*}
     */
    this.functionExecutor = init.functionExecutor || null;


    /**
     * Function called for loading a module. The module is a bag for functions used at exit points
     * The function must support an object like {"package" : string, "file": string, "ext": string} as input parameter
     * @type {function()|null}
     */
    this.moduleLoader = init.moduleLoader;

    if (init.mode) {
        check(init);
    }

    this.mode = init.mode;

    /**
     * Logger for request based logging
     */
    this.logger = init.logger;

    this.locale = init.locale;

};


function check (target) {
    if ((target.mode !== exports.modes.development ) && (target.mode !== exports.modes.productive )) {
        throw('Invalid mode. See xsodata.modes for possible values.');
    }
}