ProducerConsumer

Arithmetic expressions generator/evaluator services

Description

This application consists of two separate services: the Generator and the Evaluator. Both services operate on the principal of stream processing, where data flows between a set of transfom operations within each service.

The Generator service will create a random arithmetic expression string and send it to the Evaluator to solve via a TCP or Unix socket. The Evaluator will tokenize the expression string, verify it's validity and attempt to solve it, sending the result back to the Generator.

Requirements

NodeJS v.4.4.1 or above, you may use the provided Vagrantfile for a simulation enviornment.

Instalation

npm install

Unit Tests

npm test

Usage

Evaluator

Usage: node src/evaluator.js [Port Number or Unix Socket]

node src/evaluator.js 3000

npm run evaluator

Which will start Evaluator service on port 3000. It also runs a reporting service on port 8000 which enables you to monitor the Evaluator op/sec performance by opening monitor.html in your browser.

20:10:39.895 (1091 op/sec): #2 Received expression (55--65)*(22-40*-35)=
20:10:39.896 (1091 op/sec): #2 Sending result 75600
20:10:39.897 (1091 op/sec): #1 Received expression 71/((2-11)*82)-47=
20:10:39.897 (1091 op/sec): #1 Sending result -47.09620596205962
20:10:39.898 (1091 op/sec): #1 Received expression 23+51/(3*9)=
20:10:39.899 (1091 op/sec): #1 Sending result 2.740740740740741
20:10:39.899 (1091 op/sec): #2 Received expression (35+(-65*67))*-27=
20:10:39.900 (1091 op/sec): #2 Sending result 116640
20:10:39.901 (1091 op/sec): #1 Received expression (-49+(73+(-80+28)-57))+13=
20:10:39.901 (1091 op/sec): #1 Sending result -72
20:10:39.902 (1091 op/sec): #2 Received expression 94-98=
20:10:39.902 (1091 op/sec): #2 Sending result -4
20:10:39.903 (1091 op/sec): #1 Received expression 88-(-56--75)=
20:10:39.903 (1091 op/sec): #1 Sending result 69
20:10:39.904 (1091 op/sec): #2 Received expression 75*36=
20:10:39.904 (1091 op/sec): #2 Sending result 2700

Generator

Usage: node src/generator.js [Port Number or Unix Socket] [Delay in Seconds]

node src/generator.js 3000 1

npm run generator-slow

Connects to port 3000 and generates arithmetic expressions at a rate of one per second.

node src/generator.js 3000 0

npm run generator-fast

Connects to port 3000 and generates arithmetic expressions at the fastest possible rate.

20:10:39.897 (503 op/sec): Sending expression 71/((2-11)*82)-47=
20:10:39.898 (503 op/sec): Received result -47.09620596205962
20:10:39.898 (503 op/sec): Sending expression 23+51/(3*9)=
20:10:39.899 (503 op/sec): Received result 2.740740740740741
20:10:39.901 (503 op/sec): Sending expression (-49+(73+(-80+28)-57))+13=
20:10:39.902 (503 op/sec): Received result -72
20:10:39.903 (503 op/sec): Sending expression 88-(-56--75)=
20:10:39.904 (503 op/sec): Received result 69

mpolyak / ProducerConsumer