@sap/xsodata/lib/processor/contentIdHelper.js

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

'use strict';

const model = require('../model/model.js');
const typeConverter = require('./../utils/typeConverter');


// STEP batch create tables --> after tmp tables are created
// Calculate a ContentId from request payload
// ATTENTION the ContentId may not be save since application data may still be missing (e.g. auto generated keys).
//           for missing values nil will be inserted, so the contentId is save for tmp table creation of following requests.
// The counterpart of createNewContentIdFromRecordMapFromPayload is checkUriForContentIDs
module.exports.createNewContentIdFromRecordMapFromPayload = function (context, asyncDone) {
    const dbSeg = context.oData.dbSegmentLast;
    try {
        const keysProperties = dbSeg.getKeysProperties();
        let newContentId = dbSeg.entityType.name;

        newContentId += '(' + keysProperties.map(toValues).join(',') + ')';

        context.contentId = newContentId;
        context.logger.debug('createNewContentIdFromRecordMapFromPayload done', newContentId);
        return asyncDone(null, context);
    } catch (err) {
        return asyncDone(err, context);
    }

    function toValues(keyProperty, index, array) {
        // Here the _recordMapFromPayload is used and not the reselected data from the database (as in createAbsUrl).
        // This is because in batch processing the uris for all batch requests need to be parsed for creating the
        // tmp tables (and for uri parsing the context uris form previous requests are required) before the real
        // processing of the batch request starts.
        let value = null;
        if (dbSeg._recordMapFromPayload[keyProperty.COLUMN_NAME] !== undefined &&
            dbSeg._recordMapFromPayload[keyProperty.COLUMN_NAME] !== null) { // 0 is a valid value
            // If a key is not in the incoming payload then substitute the key with nil. This satisfies the uri parser
            // in the "batch create tables" step in order to create the tmp tables. The assumption is that this
            // key is created later on in an application exit or with an sequence and hence the correct
            // contentID is anyway created later
            value = typeConverter.serializeDbValueToUriLiteral(dbSeg._recordMapFromPayload[keyProperty.COLUMN_NAME], keyProperty);
        }
        if (array.length === 1) {
            return value ? value : 'nil';
        }

        return keyProperty.COLUMN_NAME + '=' + (value ? value : 'nil');
    }
};

// STEP batch processing --> after data is inserted into real table
// Update contentId information with values created from the db
module.exports.createNewContentIdFromDbSegSelectedRows = function (context, asyncDone) {
    const dbSeg = context.oData.dbSegmentLast;
    try {
        let contentId = dbSeg.entityType.name;
        const keysProperties = dbSeg.getKeysProperties();
        const rows = dbSeg.getRowsWithGenKey();
        const row = rows[0];

        let value;

        context.contentIdKeyObj = {};

        contentId += '(';
        if (keysProperties.length === 1) {
            const keyProperty = keysProperties[0];
            value = typeConverter.serializeDbValueToUriLiteral(row[keyProperty.COLUMN_NAME], keyProperty);
            contentId += value;
            context.contentIdKeyObj[keyProperty.COLUMN_NAME] = value;
        } else {
            for (let i = 0; i < keysProperties.length; i++) {
                const keyProperty = keysProperties[i];
                if (i !== 0) {
                    contentId += ',';
                }
                if (row[keyProperty.COLUMN_NAME] === null) {
                    contentId += keyProperty.COLUMN_NAME + '=' + 'null';
                    context.contentIdKeyObj[keyProperty.COLUMN_NAME] = 'null';
                } else if (row[keyProperty.COLUMN_NAME] === undefined) {
                    // for create, update, delete on a calcview input parameters are optional and are rendered with null in context url
                    if (dbSeg.entityType.kind === model.entityKind.inputParameters || dbSeg.entityType.kind === model.entityKind.calculationView) {
                        contentId += keyProperty.COLUMN_NAME + '=' + 'null';
                        context.contentIdKeyObj[keyProperty.COLUMN_NAME] = 'null';
                    }
                } else {
                    value = typeConverter.serializeDbValueToUriLiteral(row[keyProperty.COLUMN_NAME], keyProperty);
                    contentId += keyProperty.COLUMN_NAME + '=' + value;
                    context.contentIdKeyObj[keyProperty.COLUMN_NAME] = value;
                }

            }
        }

        contentId += ')';

        context.contentId = contentId;
        context.logger.debug('createNewContentIdFromDbSegSelectedRows done', contentId);

        return asyncDone(null, context);
    } catch (err) {
        return asyncDone(err, context);
    }
};