alirezabe/rikstv-interview

RiksTV interview

Outline

• Architecture
  • Detail:
• Installation methods
  • First build Docker images with running script:
  • Second change running Env
  • 3rd Run stack with Docker compose
  • 4th - can check web application Swagger
  • 5th - can see kafka status
  • 6th - Analytics Dashboard
• Answering the Questions
  • 1st - Which number had the longest step chain
  • 2nd - Which number went to the highest value
  • 3rd - is number x part of the step chain of another number.
  • 4th - Create a plot of all steps of number
  • Dashboard
• Scale project
• Create topic or Scale topic partition
• Terraform
• SQL Schema
• Server Spec

Architecture

This is picture of project architecture.

Detail:

• We have 3 node zookeeper cluster
• We have 3 node Kafka broker
• We use Clickhouse as a big-data database
• For analytics dashboard using Metabase
• Metabase needs a database to store service users, queries, and dashboards and we use PostgreSQL as a database
• For monitoring the Kafka cluster use Kafka-UI
• Develop producer with python
• Develop consumer with python
• Develop a web application that has REST API to answer the questions with Python FastAPI

Installation methods

For working with this repository we need install Docker and Docker Compose

You can install project in different ways:

First build Docker images with running script:

Clone project

 git clone https://github.com/alirezabe/rikstv-interview .

Set permition

chmod +x ./build-all.sh

Run build script

./build-all.sh

After that we have 3 images.

you can see them with:

docker images

The result should be like:

`

REPOSITORY                                 TAG              IMAGE ID       CREATED         SIZE
app                                        latest           115e340f0141   5 hours ago     388MB
producer                                   latest           de61f05ff6ca   5 hours ago     218MB
consumer                                   latest           5accf2becc67   5 hours ago     218MB

Second change running Env

Go to infra Directory and check two env files:

• app env file
• kafka env file

In .env_app file we have this keys:

CLICKHOUSE_HOST=clickhouse-server
CLICKHOUSE_PORT=8123
CLICKHOUSE_USER=default
CLICKHOUSE_PASSWORD=
CLICKHOUSE_DB=rikstv
CLICKHOUSE_TABLE=data_series

Environment Name	Description	Defualt value
CLICKHOUSE_HOST	we setup all service in single docker network so we can address them with service_name if setup it in bare system use IP insted	clickhouse-server
CLICKHOUSE_PORT	port of clickhost	8123
CLICKHOUSE_USER	clickhost username	default
CLICKHOUSE_PASSWORD	default password is null	NULL
CLICKHOUSE_DB	costume database name	rikstv
CLICKHOUSE_TABLE	costume table name	data_series

In .env_kafka file we have this keys:

KAFKA_TOPIC_NAME=conjecture.data
KAFKA_GROUP_ID=matine
VAULT_TOKEN='TOKEN'
VAULT_PATH='["producers"]'
PARTITIONS=4
REPLICATION_FACTOR=3
BOOTSTRAP_SERVERS=kafka1:9092,kafka2:9093,kafka:9094
CLICKHOUSE_HOST=clickhouse-server
CLICKHOUSE_PORT=8123
CLICKHOUSE_USER=default
CLICKHOUSE_PASSWORD=
CLICKHOUSE_DB=rikstv
CLICKHOUSE_TABLE=data_series

Environment Name	Description	Default value
KAFKA_TOPIC_NAME	Kafka topic name	conjecture.data
KAFKA_GROUP_ID	Producer group id	matine
VAULT_TOKEN	Vault token (not use in example)	TOKEN
VAULT_PATH	Vault paths that service can find secrets value (not use in example)	["producers"]
PARTITIONS	Number of kafka topic partitions	4
REPLICATION_FACTOR	Number of replication of Topic in Brokers	3
BOOTSTRAP_SERVERS	List of all brokers	kafka1:9092,kafka2:9093,kafka:9094
CLICKHOUSE_HOST	we setup all service in single docker network so we can address them with service_name if setup it in bare system use IP instead	clickhouse-server
CLICKHOUSE_PORT	port of Clickhost	8123
CLICKHOUSE_USER	Clickhost username	default
CLICKHOUSE_PASSWORD	default password is null	NULL
CLICKHOUSE_DB	costume database name	rikstv
CLICKHOUSE_TABLE	costume table name	data_series

3rd Run stack with Docker compose

Go to infra directory and run docker-compose file

docker-compose up -d

After download in running containers we can get running containers with following command

docker-compose ps

The result should be like this:

      Name                     Command                  State                                                    Ports                                              
--------------------------------------------------------------------------------------------------------------------------------------------------------------------
clickhouse-server   /entrypoint.sh                   Up             0.0.0.0:18123->8123/tcp,:::18123->8123/tcp, 0.0.0.0:19000->9000/tcp,:::19000->9000/tcp, 9009/tcp
infra_app_1         uvicorn main:app --host 0. ...   Up             0.0.0.0:8000->80/tcp,:::8000->80/tcp                                                            
infra_consumer_1    python3 consumer.py              Up                                                                                                         
infra_producer_1    python3 producer.py              Up                                                                                                             
kafka-ui            /bin/sh -c java --add-open ...   Up             0.0.0.0:8080->8080/tcp,:::8080->8080/tcp                                                        
kafka1              /etc/confluent/docker/run        Up             0.0.0.0:29092->29092/tcp,:::29092->29092/tcp, 0.0.0.0:9092->9092/tcp,:::9092->9092/tcp          
kafka2              /etc/confluent/docker/run        Up             0.0.0.0:29093->29093/tcp,:::29093->29093/tcp, 9092/tcp, 0.0.0.0:9093->9093/tcp,:::9093->9093/tcp
kafka3              /etc/confluent/docker/run        Up             0.0.0.0:29094->29094/tcp,:::29094->29094/tcp, 9092/tcp, 0.0.0.0:9094->9094/tcp,:::9094->9094/tcp
metabase            /app/run_metabase.sh             Up (healthy)   0.0.0.0:3000->3000/tcp,:::3000->3000/tcp                                                        
postgres            docker-entrypoint.sh postgres    Up             5432/tcp                                                                                        
zoo1                /etc/confluent/docker/run        Up             0.0.0.0:2181->2181/tcp,:::2181->2181/tcp, 2888/tcp, 3888/tcp                                    
zoo2                /etc/confluent/docker/run        Up             2181/tcp, 0.0.0.0:2182->2182/tcp,:::2182->2182/tcp, 2888/tcp, 3888/tcp                          
zoo3                /etc/confluent/docker/run        Up             2181/tcp, 0.0.0.0:2183->2183/tcp,:::2183->2183/tcp, 2888/tcp, 3888/tcp         

4th - can check web application Swagger

Now you can see swagger in expose port 8000. In this example we can see swagger in this address http://127.0.0.1:8000/docs#/

5th - can see kafka status

Now we can see kafka cluster status in this address http://127.0.0.1:8080/ui

6th - Analytics Dashboard

We Use metabase as Analytics Dashboard in this address http://127.0.0.1:3000

Answering the Questions

For answering question we can use both swagger or call raw API call

1st - Which number had the longest step chain

curl -X 'GET' \
  'http://172.16.40.40:8000/longest_step_chain' \
  -H 'accept: application/json'

The answer is:

{
  "longest": 31917434126612
}

2nd - Which number went to the highest value

curl -X 'GET' \
  'http://172.16.40.40:8000/highest_value' \
  -H 'accept: application/json'

The answer is:

{
  "longest": 77293533689575
}

3rd - is number x part of the step chain of another number.

In this example x = 1024

curl -X 'GET' \
  'http://172.16.40.40:8000/part/1024' \
  -H 'accept: application/json'

The answer is:

[
  [
    2361437172277
  ],
  [
    29009624858921
  ],
  [
    35246528388678
  ],
  [
    44108625874832
  ],
  [
    55806168045825
  ],
  [
    58834351055852
  ],
  [
    67949987565981
  ],
  [
    76279233209058
  ],
  [
    76375094243638
  ]
]

4th - Create a plot of all steps of number

curl -X 'GET' \
  'http://172.16.40.40:8000/plot/76375094243638' \
  -H 'accept: application/json'

Dashboard

There is a dashboard in Metabase for above questions

Scale project

For scale producer can use this command:

docker-compose up -d --scale producer=3

For scale consumer can use this command:

docker-compose up -d --scale consumer=4

and now can see the result in Kafka-UI

Create topic or Scale topic partition

For creating new topic can use this command

docker exec kafka1 kafka-topics --create --topic alireza.test --bootstrap-server kafka1:9092

For scale topic partition use this command

docker exec kafka1 kafka-topics --alter --topic alireza.test --bootstrap-server kafka1:9092 --partitions 40

Terraform file

we have for Terraform files for setup cluster with Docker

• providers.tf for Providers than need to deploy
• images.tf for Docker Image resources
• containers.tf for Docker containers
• values.tf for Docker values

After build all images with build-all.sh script run this command to run cluster.

terraform init
terraform plan -out rikstv.tfplan
terraform apply

Sql Schema for clickhouse

I use a flat schema for storing data in clickhouse because MergeTree in clickhouse has great performance for aggregation queries

CREATE TABLE IF NOT EXISTS TABLE_NAME 
(
        number UInt64,
        step UInt64,
        value UInt64,
        timestamp DateTime
)

Server Spec

The minimum Server spec for run this stack is:

Resource	Quantity
Process	8 vCore
Memory	12 GB
Storage	50 GB

Sequence Diagram

Sequence diagram for producer is here:

future

temp: add vault, monitoring stack, log stack

production ready

pods in kube kafka in bare in ceph