This repository is an coding evaluation task for a company I've applied.
Details for the task is omitted for now.
Project needs a mysql database. A sample DDL SQL is provided here:
CREATE USER 'validator'@'localhost'
IDENTIFIED BY 'validator';
CREATE DATABASE validator;
GRANT ALL PRIVILEGES ON validator.* TO 'validator'@'localhost';CREATE TABLE `customer` (
`id` int(11) unsigned NOT NULL AUTO_INCREMENT,
`name` varchar(255) NOT NULL,
`active` tinyint(1) unsigned NOT NULL DEFAULT '1',
PRIMARY KEY (`id`)
);INSERT INTO `customer` VALUES (1,'Big News Media Corp',1),(2,'Online Mega Store',1),(3,'Nachoroo Delivery',0),(4,'Euro Telecom Group',1);CREATE TABLE `ip_blacklist` (
`ip` int(11) unsigned NOT NULL,
PRIMARY KEY (`ip`)
);INSERT INTO `ip_blacklist` VALUES (0),(2130706433),(4294967295);CREATE TABLE `ua_blacklist` (
`ua` varchar(255) NOT NULL,
PRIMARY KEY (`ua`)
);INSERT INTO `ua_blacklist` VALUES ('A6-Indexer'),('Googlebot-News'),('Googlebot');CREATE TABLE `hourly_stats` (
`id` int(11) unsigned NOT NULL AUTO_INCREMENT,
`customer_id` int(11) unsigned NOT NULL,
`time` timestamp NOT NULL,
`request_count` bigint(20) unsigned NOT NULL DEFAULT '0',
`invalid_count` bigint(20) unsigned NOT NULL DEFAULT '0',
PRIMARY KEY (`id`),
UNIQUE KEY `unique_customer_time` (`customer_id`,`time`),
KEY `customer_idx` (`customer_id`),
CONSTRAINT `hourly_stats_customer_id` FOREIGN KEY (`customer_id`) REFERENCES `customer` (`id`) ON DELETE CASCADE ON UPDATE NO ACTION
);RequestValidator is a spring-boot project.
To package and run as a executable jar, first compile and package the project wih maven mvn package command.
Tests will be executed and executable jar will be generated in the target folder.
To start the project as a server run:
java -jar target/request-validator-1.0-SNAPSHOT.jar
Project is serving on HTTP port 8090.
All HTTP request to be validated should be in the given JSON format:
{
"customerID":1,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}All requests should be send with HTTP POST to /processor with application/json content type. Example:
POST http://localhost:8090/processor
Content-Type: application/json
{
"customerID":1,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}All examples here is implemented as junit4 test in the test folder in the project. All valid requests are reponded with OK (200)
and all invalids are with BAD REQUEST (400) HTTP status codes.
{
"customerID":1,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}OK
{
Malformed JSON
{
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}customerID cannot be null
{
"customerID":5,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}Customer ID 5 not found
{
"customerID":3,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}Customer with ID 3 is disabled
{
"customerID":3,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"127.0.0.1",
"timestamp":1500000000
}Remote IP 127.0.0.1 [2130706433] is blacklisted
POST http://localhost:8090/processor
Content-Type: application/json
User-Agent: A6-Indexer
{
"customerID":1,
"tagID":2,
"userID":"aaaaaaaa-bbbb-cccc-1111-222222222222",
"remoteIP":"123.234.56.78",
"timestamp":1500000000
}User-Agent A6-Indexer is blacklisted
POST http://localhost:8090/stats
Content-Type: application/json
{
"customerID": 1,
"timestamp": 1542574800000
}{
"hourlyStats": {
"0": {
"requestCount": 24,
"invalidCount": 0
},
"1": {
"requestCount": 23,
"invalidCount": 0
},
"2": {
"requestCount": 22,
"invalidCount": 0
},
"3": {
"requestCount": 21,
"invalidCount": 0
},
"4": {
"requestCount": 20,
"invalidCount": 0
},
"5": {
"requestCount": 19,
"invalidCount": 0
},
"6": {
"requestCount": 18,
"invalidCount": 0
},
"7": {
"requestCount": 17,
"invalidCount": 0
},
"8": {
"requestCount": 16,
"invalidCount": 0
},
"9": {
"requestCount": 15,
"invalidCount": 0
},
"10": {
"requestCount": 14,
"invalidCount": 0
},
"11": {
"requestCount": 13,
"invalidCount": 0
},
"12": {
"requestCount": 12,
"invalidCount": 0
},
"13": {
"requestCount": 11,
"invalidCount": 0
},
"14": {
"requestCount": 10,
"invalidCount": 0
},
"15": {
"requestCount": 9,
"invalidCount": 0
},
"16": {
"requestCount": 8,
"invalidCount": 0
},
"17": {
"requestCount": 7,
"invalidCount": 0
},
"18": {
"requestCount": 6,
"invalidCount": 0
},
"19": {
"requestCount": 5,
"invalidCount": 0
},
"20": {
"requestCount": 4,
"invalidCount": 0
},
"21": {
"requestCount": 3,
"invalidCount": 0
},
"22": {
"requestCount": 2,
"invalidCount": 0
},
"23": {
"requestCount": 1,
"invalidCount": 0
}
},
"totalRequestCount": 300
}Project provides junit4 test in the test folder. Tests are executed on a in-memory test database. Schema creation and sample data feeding is handled automatically.
A sample case for every possible scenario is tried to be provided.
To run the tests:
mvn test
Since the project is for evaluational purposes, performance optimisation is not considered:
- For example all requests are stored in mysql database, however in a real production environment either a in-memory database or cache server should be chosen as data store.
- The HTTP layer is handled via
spring-boot. In real world, a custom HTTP interceptor may been developed and benchmarked withspring-boot, then choose the one that has most performance.
To extract the request body in the CollectorRequestInterceptor.preHandle method, request.getInputStream() method needs to be called.
However, request.getInputStream() method cannot be called more than once (*).
A workaround is provided here.
Long and IP address string conversion is done with the code provided here