Dimensions: buildDimensions()

in code/sample-app/src/lib/logging/logger.js [198:274]

• 34 lines of code
• 9 McCabe index (conditional complexity)

                Dimensions: buildDimensions(service, options),
                Timestamp: new Date(),
                Unit: unit,
                Value: value
            },
        ],
        Namespace: namespace
    };
    return metric
}

/**
 * Transforms arguments into dimensions to EMF. 
 *   
 * @property    {String}        SERVICE_NAME    Environment variable defining the service name to be used as metric dimension. This variable can be defined in the SAM template.
 * 
 * @param       {Object}        dimensions Dict containing metric dimensions and namespace. Optional. (e.g. {customer: customerId})
 *  
 * @returns     {Object}        Custom Dimensions object.
 */
const buildEMFDimensions = (dimensions) => {
    let service = process.env.SERVICE_NAME !== undefined ? process.env.SERVICE_NAME : 'service_undefined'

    if (dimensions) {
        if (dimensions.service !== undefined) service = dimensions.service
        delete dimensions.namespace
        delete dimensions.service
    }

    return dimensions
}


/**
 * Transforms arguments into StatsD Metric Data. 
 *   
 * @property    {String}        SERVICE_NAME    Environment variable defining the service name to be used as metric dimension. This variable can be defined in the SAM template.
 * 
 * @param       {String}        name    Metric name. 
 * @param       {MetricUnit}    unit    Metric unit enum value (e.g. MetricUnit.Seconds). Metric units are available via MetricUnit Enum.
 * @param       {Number}        value   Metric value. 
 * @param       {Object}        options Dict containing metric dimensions and namespace. Optional. (e.g. {customer: customerId})
 *  
 * @returns     {String}        Custom Metric object. MONITORING|<metric_value>|<metric_unit>|<metric_name>|<namespace>|<dimensions>
 */
const buildStatsDMetricData = (name, unit, value, options) => {
    let namespace = 'MonitoringApp',
        service = process.env.SERVICE_NAME !== undefined ? process.env.SERVICE_NAME : 'service_undefined'

    if (options) {
        if (options.namespace !== undefined) namespace = options.namespace
        if (options.service !== undefined) service = options.service
        delete options.namespace
        delete options.service
    }

    return `MONITORING|${value}|${unit}|${name}|${namespace}|${buildDimensionsStatsDFormat(service, options)}`
}


/**
 * Builds correct format for custom metric dimensions from args.
 *  
 * CloudWatch accepts a max of 10 dimensions per metric
 * we include service name as a dimension
 * so we take up to 9 values as additional dimensions
 * before we return our dimensions array
 * 
 * @param   {JSON}  service             Service dimension. (e.g. {service: 'value'}) 
 * @param   {JSON}  extra_dimensions    Extra metric dimensions and. Optional. (e.g. {customer: customerId})
 * 
 * @returns {Array} Dimensions in the form of [{Name: 'dim1', Value: 'val1'}, {Name: 'dim10', Value: 'val10'}]  
 */
const buildDimensions = (service, extra_dimensions) => {
    let dimensions = [{ Name: 'service', Value: service }]
    if (extra_dimensions) {
        Object.keys(extra_dimensions).forEach(k => {