Differences between revisions 5 and 6

V2 Inspector2 Specification

V2Master | V2HighLevelDesign

Contents

V2 Inspector2 Specification
Introduction
Development
Main Menu
Screens
Data Synchronization
1. Download
  1. Download Algorithm
2. Data Upload
  1. Upload Algorithm

Introduction

Development

See V2Inspector2Todo

Main Menu

Home -
Inspection Records - Displays a list of Inspection Records
Inspection Items - Displays a list of Inspection Items
Synchronize - Displays counts of Inspection Records and Inspection Items. Buttons for Upload and Download data.
Preferences -
About Inspector - Displays Inspector version number and release date
Contact Us

Screens

Home
Inspection Records (list)
Inspection Record Detail
Inspection Record New/Edit
Inspection Items (list)
Inspection Item Detail
Inspection Item New/Edit
Synchronize
Statistics
Preferences
About Inspector
Contact Us

Data Synchronization

Key data fields for synchronization:

local_id - Primary key in the device (local) database
local_is_dirty - If set to on-zero, then the record has been changed on the device
local_is_conflict - If set, then the record has been change on the device and the server, and cannot be uploaded
id - The server's primary key
update_count - The server's update count. The device should never change this field

Download

Data in JSON format is download from the server, from the following tables:
- tags - Inspection Items
- scans - Inspection Records
- photos - Inspection Photos (not implemented yet)

Download Algorithm

For a single downloaded record:

  table = name of the table being processed
  new_record = record downloaded from server

  old_record = db.getById(table, record.id) -- Record from client device database

  if ( old_record == null ) {

    new_record.local_is_dirty = 0;
    new_record.local_is_conflict = 0
    db.insert(table, new_record) -- local_id is set by the database server

  } else {

    if ( new_record.update_count != old_record.update_count ) { // Server record was updated

      if ( old_record.local_is_dirty ) {

        db.updateById(table, old_record.id, {local_is_conflict: 1}) -- Set old_record.local_is_conflict = 1

      } else {

        record.local_is_conflict = 0
        db.updateById(table, new_record.id, new_record) -- Replace old_record with new_record (or delete & insert?)

      }
    }
  }

Data Upload

Upload Algorithm

Only upload records records that meet one the following conditions:
1. local_is_dirty != 0
2. id == null
Do not upload records where local_is_conflict != 0

To Do What are the responses from the server in the following cases:

Success
1. Insert On a new record does the server respond with the new id value or path to access the new record?
2. Update Does the server respond with the updated update_count. If not, can we always guarantee it is incremented by one
Conflict What is the response when the update_count of uploaded record doesn't not match that on the server

Possible responses to an insert/update:

inserted: id updated: update_count conflict: an error code

For a single record to upload:

  table = name of the table being processed
  record = record to upload

  create a JSON string from the record, which does not include the following fields:
    local_id
    local_is_dirty
    local_is_conflict

  if ( record.id == null ) { // Insert a new record

    POST JSON to "http://{url}/{table}.json"

    record.id = id from server     -- how to get the new id from server?
    record.local_is_dirty = 0
    record.local_is_conflict = 0
    record.update_count = 1 (or 0?)

    db.updateByLocalId(record.local_id, record)

  } else { // Update existing record

    PUT JSON to "http://{url}/{record.id}/{table}.json

    if (response == OK) {

      -- do nothing or download record again to get new update_at value? 
      record.update_count = record.update_count + 1

      db.updateByLocalId(record.local_id, record)

    } else if ( response == conflict ) {

      db.updateById(record.id, {local_is_conflict: 1}) -- Set old_record.local_is_conflict = 1

    } else {

      report error

    }
  }

Deletions are marked like this.	Additions are marked like this.
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== Next Steps == 1. --(Convert ''Edit Inspection Item'' model to a normal page)-- 1. Convert ''Edit Inspection Record'' model to a normal page 1. --(Implement ''New Inspection Item'')-- 1. Implement ''New Inspection Record'' 1. --(Implement ''photos'' database table)-- 1. --(Implement simple ''Photos List'' & Photos Detail page (with metadata only))-- 1. Implement statistics page 1. Implement ability to add photos to an inspection record 1. Implement ''Show Photo Photos'' for Inspection Record 1. Implement ''Photos List'' for Inspection Record 1. Implement Download Algorithm (see below) 1. Implement Upload Algorithm 1. Add ''Get Geolocation'' button to ''New & Edit Inspection Record'' screens 1. Implement upload photos 1. Implement form validation for Inspection Item 1. Implement form validation for Inspection Record	See [[V2Inspector2Todo]]