TrackDuration

TrackDuration.ts

let durationSequence = 1;
function TrackDuration(options?: { enabled?: boolean; excludes?: Array<string> }) {
    return function TrackDuration(target: any, propertyKey?: string, descriptor?: PropertyDescriptor) {
        if (options?.enabled === false) {
            return;
        }
        let methods: any[];
        //is a method
        if (propertyKey) {
            methods.push(propertyKey);
            //is a class
        } else {
            methods = Object.getOwnPropertyNames(target.prototype);
        }
        const excludes = options?.excludes ?? [];
        //filter out any excluded methods
        methods = methods.filter(x => !excludes.includes(x));

        methods.forEach((methodName) => {
            const originalMethod = target.prototype[methodName];
            //skip non-functions
            if (typeof originalMethod !== 'function') {
                return;
            }

            target.prototype[methodName] = function executeFunctionWrapped(...args: any[]) {
                let logger = this.logger instanceof Logger ? this.logger : console;

                const start = Date.now();
                let result;
                const seq = durationSequence++;
                try {
                    logger.log(`req-${seq} ${methodName} begin`);
                    result = originalMethod.apply(this, args);
                    return result;
                } finally {
                    Promise.resolve(result).finally(() => {
                        logger.log(`req-${seq} ${methodName} end (${Date.now() - start}ms)`);
                    });
                }
            };
        });
    };
}

This is an annotation to track the duration of a function. it prints out how long the method took to run.