# VIVOCloud Recording System

## Overview

### Parts list
1. Camera side
1. Server side
* S3
* EC2
* Account Server
* Playback Server
* lambda
* Recording server
* Redis
* DynamoDB
* AWS IOT STS endpoint
1. Client side
* APP
* Web

### Actions between parts

graph LR
  C[Camera]
  F[Web/APP]-->|login|A[Account]
  F -->|play| P[Playback]
  subgraph SERVER
  AS(AWS-STS)
  D[(DynamoDB)]
  R(Redis)
  P --> |get media|S((S3))
  S --> |event call|RS{{Recording}}
  A--> |query owner| D
  A -->|query session, put credential| R
  A --> |create credential|AS
  P --> |query intervals| D
  P --> |query session, query credential| R
  RS--> |insert interval| D
  RS-->|get media|S
  I(IOT-STS)
  end
  C -->|put media|S
  C -->|create credential|I

## Parts

1. S3
* Store all recording media files
* Store all archived media files
* Support upload HTTPS request
2. DynamoDB
* Store all interval information of medias
* S3 filename
* Begin time and end time in local time and UTC
* Timezone and DST inforamtion
* Store all information of archives
* S3 filename
* Begin time, end time and create time
* Create from whitch camera
4. Redis
* Cache Storage credentials for each user
5. AWS IOT STS endpoint
* Support camera get a temporary credential by HTTPS request with cerificate
7. Camera
* Get frame and compose 3gp type media files
* Refresh Storage credential form IOT certificate
* Put 3gp files to Storage by HTTPS request with credential
* Varify AWS server with AWS root CA
8. Recording server
* A AWS managed lambad
* Support Storage new file event
* Parse file to get interval information and insert to Database
9. Client
* User login Account server
* Send query API to Playback server, then show timeline and video
* Send archives API to keep media avoid be recycled
10. Account server
* Create a user session for client when login
* Create a credential of Storage in cache when user login
11. Playback server
* Check API with user session
* Get crendtial of Storage form Cache
* Support HTTPS requests:
* Query recorded days in a month
* Query recording intervals in a day
* Play recording files in a time
* Create archive with a interval
* Query all archives
* Play/Download/Delete archive with a archive ID

## Flow of Actions

### Camera Recording

sequenceDiagram
	Camera->>+IOT STS: HTTPS request + cetificate
	IOT STS->>-Camera: temporary credential
    Camera->>+S3:upload 3gp file + credential
    S3->>-Camera:ok
    S3->>+Recording:trigger event with obj key
    Recording->>+S3:HTTPS request
    S3->>-Recording:download 3gp
    Note over Recording:parse 3gp
    Recording->>+DynamoDB:insert new file interval
    DynamoDB->>-Recording:ok
    Recording->>-S3:ok

### Client login

sequenceDiagram
	Client->>+Account: HTTPS request + username + password
    Account->>Account: create session
    Account->>+AWS STS: create temporary credential
    AWS STS->>-Account: downlaod credential
    Account->>+Redis: Add session and credential
    Redis->>-Account: ok
    Account->>-Client: user session

### Client Playback - get intervals and calendar

sequenceDiagram
	Client->>+Playback: HTTPS request + user session
    Playback->>+Redis: verify user session
    Redis->>-Playback: ok
	Playback->>+DynamoDB: query camera owner
    DynamoDB->>-Playback: owner ID
    Playback->>+DynamoDB: query interval of files
    DynamoDB->>-Playback: interval list in JSON
    Playback->>-Client: JSON response

### Client Playback - play media

sequenceDiagram
	Client->>+Playback: HTTPS request + user session
    Playback->>+Redis: verify user session
    Redis->>-Playback: ok
    Playback->>+Redis: get credential
    Redis->>-Playback:downlaod credential
	Playback->>+DynamoDB: query camera owner
    DynamoDB->>-Playback: owner ID
    Playback->>+DynamoDB: find the file
    DynamoDB->>-Playback: return a s3 obj key
    Playback->>+S3: GetObj HTTPS request with credential
    S3->>-Playback: dowwnload 3gp
    Playback->>-Client: downlaod 3gp
    Note over Client: render the 3gp

### Client Archive - Create

sequenceDiagram
	Client->>+Playback: HTTPS request + user session
    Playback->>+Redis: verify user session
    Redis->>-Playback: ok
    Playback->>+Redis: get credential
    Redis->>-Playback:downlaod credential
	Playback->>+DynamoDB: query camera owner
    DynamoDB->>-Playback: owner ID
    Playback->>+DynamoDB: query files in the range
    DynamoDB->>-Playback: file list in JSON
    loop all files
        Playback->>+S3: GetObj HTTPS request with credential
        S3->>-Playback: dowwnload all 3gp files
    end
    Note over Playback: Merge files
    Playback->>+S3: Upload archived 3gp
    S3->>-Playback: ok
    Playback->>+DynamoDB: insert archive information
    DynamoDB->>-Playback: ok
    Playback->>-Client: JSON response

### Client Archive - Query, Deelte

sequenceDiagram
	Client->>+Playback: HTTPS request + user session
    Playback->>+Redis: verify user session
    Redis->>-Playback: ok
    Playback->>+Redis: get credential
    Redis->>-Playback:downlaod credential
	Playback->>+DynamoDB: query camera owner
    DynamoDB->>-Playback: owner ID
    Playback->>+DynamoDB: query command
    DynamoDB->>-Playback: result in JSON
    Playback->>-Client: JSON response

### Client Archive - Download, Play

sequenceDiagram
	Client->>+Playback: HTTPS request + user session
    Playback->>+Redis: verify user session
    Redis->>-Playback: ok
    Playback->>+Redis: get credential
    Redis->>-Playback:downlaod credential
	Playback->>+DynamoDB: query camera owner
    DynamoDB->>-Playback: owner ID
    Playback->>+DynamoDB: query archive s3 obj key
    DynamoDB->>-Playback: return a s3 obj key
    Playback->>+S3: create pre-signed URL
    S3->>-Playback:string in JSON
    Playback->>-Client: JSON response