UdaConnect

Overview

Background

Conferences and conventions are hotspots for making connections. Professionals in attendance often share the same interests and can make valuable business and personal connections with one another. At the same time, these events draw a large crowd and it's often hard to make these connections in the midst of all of these events' excitement and energy. To help attendees make connections, we are building the infrastructure for a service that can inform attendees if they have attended the same booths and presentations at an event.

Goal

You work for a company that is building a app that uses location data from mobile devices. Your company has built a POC application to ingest location data named UdaTracker. This POC was built with the core functionality of ingesting location and identifying individuals who have shared a close geographic proximity.

Management loved the POC so now that there is buy-in, we want to enhance this application. You have been tasked to enhance the POC application into a MVP to handle the large volume of location data that will be ingested.

To do so, you will refactor this application into a microservice architecture using message passing techniques that you have learned in this course. It’s easy to get lost in the countless optimizations and changes that can be made: your priority should be to approach the task as an architect and refactor the application into microservices. File organization, code linting -- these are important but don’t affect the core functionality and can possibly be tagged as TODO’s for now!

Technologies

• Flask - API webserver
• SQLAlchemy - Database ORM
• PostgreSQL - Relational database
• PostGIS - Spatial plug-in for PostgreSQL enabling geographic queries]
• Vagrant - Tool for managing virtual deployed environments
• VirtualBox - Hypervisor allowing you to run multiple operating systems
• K3s - Lightweight distribution of K8s to easily develop against a local cluster

Running the app

The project has been set up such that you should be able to have the project up and running with Kubernetes.

Prerequisites

We will be installing the tools that we'll need to use for getting our environment set up properly.

1. Install Docker
2. Set up a DockerHub account
3. Set up kubectl
4. Install VirtualBox with at least version 6.0
5. Install Vagrant with at least version 2.0
6. Helm with at least version 3.2.1

Environment Setup

To run the application, you will need a K8s cluster running locally and to interface with it via kubectl. We will be using Vagrant with VirtualBox to run K3s.

Initialize K3s

In this project's root, run vagrant up.

$ vagrant up

The command will take a while and will leverage VirtualBox to load an openSUSE OS and automatically install K3s. When we are taking a break from development, we can run vagrant suspend to conserve some ouf our system's resources and vagrant resume when we want to bring our resources back up. Some useful vagrant commands can be found in this cheatsheet.

Set up kubectl

After vagrant up is done, you will SSH into the Vagrant environment and retrieve the Kubernetes config file used by kubectl. We want to copy the contents of this file into our local environment so that kubectl knows how to communicate with the K3s cluster.

$ vagrant ssh

You will now be connected inside of the virtual OS. Run sudo cat /etc/rancher/k3s/k3s.yaml to print out the contents of the file. You should see output similar to the one that I've shown below. Note that the output below is just for your reference: every configuration is unique and you should NOT copy the output I have below.

Copy the contents from the output issued from your own command into your clipboard -- we will be pasting it somewhere soon!

$ sudo cat /etc/rancher/k3s/k3s.yaml

apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCk1JSUJWekNCL3FBREFnRUNBZ0VBTUFvR0NDcUdTTTQ5QkFNQ01DTXhJVEFmQmdOVkJBTU1HR3N6Y3kxelpYSjIKWlhJdFkyRkFNVFU1T1RrNE9EYzFNekFlRncweU1EQTVNVE13T1RFNU1UTmFGdzB6TURBNU1URXdPVEU1TVROYQpNQ014SVRBZkJnTlZCQU1NR0dzemN5MXpaWEoyWlhJdFkyRkFNVFU1T1RrNE9EYzFNekJaTUJNR0J5cUdTTTQ5CkFnRUdDQ3FHU000OUF3RUhBMElBQk9rc2IvV1FEVVVXczJacUlJWlF4alN2MHFseE9rZXdvRWdBMGtSN2gzZHEKUzFhRjN3L3pnZ0FNNEZNOU1jbFBSMW1sNXZINUVsZUFOV0VTQWRZUnhJeWpJekFoTUE0R0ExVWREd0VCL3dRRQpBd0lDcERBUEJnTlZIUk1CQWY4RUJUQURBUUgvTUFvR0NDcUdTTTQ5QkFNQ0EwZ0FNRVVDSVFERjczbWZ4YXBwCmZNS2RnMTF1dCswd3BXcWQvMk5pWE9HL0RvZUo0SnpOYlFJZ1JPcnlvRXMrMnFKUkZ5WC8xQmIydnoyZXpwOHkKZ1dKMkxNYUxrMGJzNXcwPQotLS0tLUVORCBDRVJUSUZJQ0FURS0tLS0tCg==
    server: https://127.0.0.1:6443
  name: default
contexts:
- context:
    cluster: default
    user: default
  name: default
current-context: default
kind: Config
preferences: {}
users:
- name: default
  user:
    password: 485084ed2cc05d84494d5893160836c9
    username: admin

Type exit to exit the virtual OS and you will find yourself back in your computer's session. Create the file (or replace if it already exists) ~/.kube/config and paste the contents of the k3s.yaml output here.

Afterwards, you can test that kubectl works by running a command like kubectl describe services. It should not return any errors.

Steps

Each microservice is located into the root directory, more specifically into the modules folder

Deploy each microservice in the following order:

SETTING UP A KAFKA

1. Now, you can add the chart repository below.

$ helm repo add bitnami https://charts.bitnami.com/bitnami

$ helm repo list

NAME        	URL                                           
bitnami     	https://charts.bitnami.com/bitnami            

2. Install the kafka helm chart

$ helm install kafka-release bitnami/kafka           

You'll see an output like that.

NAME: kafka-release
LAST DEPLOYED: Wed Dec 23 19:33:16 2020
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
...

3. After a while, check that kafka is running inside Kubernetes cluster entering the commands below:

$ kubectl get pods
NAME                        READY   STATUS    RESTARTS   AGE
kafka-release-zookeeper-0   1/1     Running   0          7m30s
kafka-release-0             1/1     Running   1          7m30s

Now, you will be able to deploy the services. For a better understanding, check the architectural diagram

PERSON-MICROSERVICE

1. Get into the '01-person-microservice' folder and run $ kubectl apply -f deployment/
2. When the pods are running, execute the script located in 01-person-microservice/scripts/run_db_command.sh with the pod identifier sh scripts/run_db_command.sh <POSTGRES_DB_POD_NAME> The step 2 will populate the postgres database (The pod name will be something like (postgres-person-xxxxxid-pod))
3. Access the http://localhost:30001/api/persons for testing

CONNECTION-MICROSERVICE

1. Get into the '02-connection-microservice' folder and run $ kubectl apply -f deployment/
2. after you have the pods running, execute the script located in 02-connection-microservice/scripts/run_db_command.sh with the pod identifier sh scripts/run_db_command.sh <POSTGRES_DB_POD_NAME>. (The pod name will be something like (postgres-geoconnections-xxxxxid-pod)) The step 2 will populate the postgres database
3. Access the http://localhost:30002/api/persons/600/connection?start_date=2020-01-01&end_date=2020-12-30&distance=5 for testing
4. You will not see any response once we have no records yet into database

LOCATION-EVENT-MICROSERVICE

1. Get into the '03-location-event-microservice' folder and run `$ kubectl apply -f deployment/

LOCATION-PROCESSOR-MICROSERVICE

1. Get into the '04-location-processor-microservice' folder and run `$ kubectl apply -f deployment/

FRONTEND

1. Get into the '05-frontend' folder and run `$ kubectl apply -f deployment/

Wait until you have every pod running and access the http://localhost:30000/

Verifying it Works

Once the project is up and running, you should be able to send requests to grpc location-event-microservice kubectl get pods and kubectl get services - should both return udaconnect-app, udaconnect-api, and postgres

These pages should also load on your web browser:

• http://localhost:30002/ - OpenAPI Documentation
• http://localhost:30002/api/persons/1/connection?start_date=2020-01-01&end_date=2020-12-30&distance=5
• http://localhost:30001/api/persons - Base path for person microservice API
• http://localhost:30000/ - Frontend ReactJS Application

To send records, please execute the python file for location-event-microservice grpc-client