Table of contents

Summary

• Introduction
• Overview
• Communication
  • Front to daemon
  • Daemon to database
• Daemon
  • Entity
• DB tables
• Prototype

hashira Design overview

Functions of hashira on PC

CLI and GUI

• Add a new task and place it on Backlog
• Change status of tasks to ToDo, Doing, and Done
• Add interrupter task, place it on Doing directory
• Show list of tasks on each status

GUI specific

• Show chart to indicate how long time spent to current task

Functions of hashira on Android

Application

• Add a new task and place it on Backlog
• Change status of tasks to ToDo, Doing, and Done
• Add interrupter task, place it on Doing directory
• Show list of tasks on each status

Widget

• Add a new task and place it on Backlog
• Show list of tasks on Backlog
• Show current task and how long time spent to the task

Functions of Daemon

• It is for making hashira work even there's no network
• Daemon has database to cache the tasks and "commands"
  • "commands" means a unit of modifications to tasks. e.g) Add new task, move task to ToDo, and so on
  • "commands" are used to sync with datastore
• If network is available, then sync registered or changed tasks with cloud

Functions of datastore

• It is assumed to place on cloud. it is for syncing data between devices
• It accepts "commands" to add or modify tasks
• Daemon can retrieve chunk of commands with from-to query to reflect datastore's update to local database

Modules

Communication

• Use GRPC for communication between front and daemon
• Use GRPC for communication between daemon and datastore

Communication between front to daemon

Overview

• hashira uses GRPC for communication between front and daemon

PC

CLI and Daemon

• CLI to Daemon
  • Add a new task to Backlog
  • Change task's status
  • Show task list
• Daemon to CLI
  • None

GUI and Daemon

• Assume to use Electron

• GUI to daemon

  • Add a new task to Backlog, ToDo, Doing, Done
  • Change task's status
  • Show task list on each status
  • Show consume of each task

• Daemon to GUI

  • notify any update of tasks

• TODO: Show GUI picture

Android

application and daemon

• GUI to Daemon

  • Add a new task to Backlog, ToDo, Doing, Done
  • Change task's status
  • Show task list on each status
  • Show consume of each task

• Daemon to GUI

  • Notify any update of tasks

• TODO: Show GUI picture

Widget and Daemon

• Widget to Daemon

  • Add a new task to Backlog
  • Change task's status to Done
  • Show task list

• Daemon to widget

  • Notify any update of tasks

• TODO: Show GUI picture

Communication between daemon to datastore

Overview

• Use GRPC for communication between daemon and datastore
  • Daemon send array of command, and datastore will apply them
  • Daemon retrieves updates from datastore periodically for syncing

GRPC APIs

• Use Hashira service. See daemon overview.

Overview of Daemon's functionality

• Daemon has responsibility for
  • Receive requests from front end.
  • Caches commands and reflect them to local document store for working without network.
  • Send chunk of commands to datastore for syncing.
  • Receive chunk of data to sync with datastore.

Caches data entities on local document store

• Caches commands and reflect them to local document store for working without network.
  • here is data entities for local document store

Sync with datastore

• Daemon has a document store to cache commands from front end, and store data from datastore.
• Periodically, daemon tries to perform syncing local data with datastore.
  • Send local commands, that are "not synced yet", to datastore.
  • Retrieve chunk of data. They are JSON formatted and represent "1 week of data", for example.
  • Daemon stores 10 weeks of data in local document store.

GRPC API

• Hashira Service

  • send(array of command)
    • sends specified commands.
  • retrieve(from, to (number of weeks)) array of task
    • returns array of task with specified term.

• command and related enumeration

what (enum)

command (structure)

Command handling

• When daemon receives commands, cache them and return ok immediately.

• If daemon is online, send cached commands to datastore.

• When datastore receives commands and succeed to apply them, datastore sends notification to daemon.

• At daemon receiving notification, retrieve chunk of data from datastore for syncing.

• When daemon succeed to apply them, daemon sends notification to front end.

• At front end receiving notification, retrieve chunk of data from daemon.

• When front end succeed to retrieve chunk of data, render them.

• If daemon is offline, postpone to send commands to datastore.

  • Instead, daemon applies the cached commands to local document store, and send notification to front end as same as written above.

Data entities for local document store

• Two data entities are declared for local document store.

  • Tasks
  • Priorities

• Refer proto file for latest data entity declaration.

Tasks

• Tasks represents each ToDo items.

message Task {
    string id        = 1;
    string name      = 2;
    Place  place     = 3;
    bool   isDeleted = 4;
}

Priorities

• Priorities represents priority of each task.
  • Priorities are represented as its place and array of task ID.
  • The ID placed on lower index means higher priority.

message Priority {
    Place place         = 1;
    repeated string ids = 2;
}

Database tables

User

Task

• task represents tasks and its status.

Status

• status represents task's status. like "Backlog", "ToDo", "Doing" and "Done" will be inserted here.

Consume

• consume represents how many times are consumed for specified task.

Label

• label represents task's label. this is used to task classification.

ER diagram

Prototype

Here's design memorandum of hashira prototyping, for checking usability.

Feature notice of prototype version

• No performance/resource consideration
• front end is for linux PC only
  • CUI and GUI (may use astilectron)
• No cloud syncing
• No "Doing" time calculation
• Daemon uses MySQL as DB

Sequence of tweaking tasks