Dayary

Dayary is a dairy tool that runs in a web app, ecrypts records and allows to sync them with a cloud storage.

To use it simply browse https://barahilia.github.io/dayary in Chrome or Safary.

All the records are storred locally, encrypted before save and decrypted at viewing or editing only. Dropbox can be used for backup and restore of encrypted records.

Other dairy tools

There are other dairy tools I had used or considered to use before deciding to build something different. Here are them:

• Word from MS Office, Writer from LibreOffice or any other word processor
• Blogging platforms like Wordpress or Jekyll
• Moment Diary app for iPad and Android
• Dairy services online and apps for iOS and Android

Features

And here are what I needed from the dairy tool and haven't found in the existing ones:

• Multiplatform - ability to read and write the diary at least on PC, iOS and Android devices
• Autosaving and autobackup to a cloud storage
• Security - records must be encrypted with strong security locally and decrypted only at the user access time
• Data organization as entries with convenient and accessible view for all the entries
• Convertion - ability to import and export entries with the other tools
• Lockable workspace
• Customisable - ability to add features
• Offline work - availability without network access and ability to sync

Architecture

The tool is an HTML 5 web app loaded by and running in a browser. AngularJS framework is used to build the presentation and business logic layers. Web SQL serves for the local data layer. Dropbox was chosen for external data storage in the cloud.

It should be noted, that Web SQL is a deprecated specification, but it is fully supported by the target browsers - Chrome and Safari, - and by phantom.js used for headless testing.

The application to be served by any hosting, I chose for GitHub Pages. The application should be cached by the browser and be available offline.

Design

The main unit of work is dairy record:

{
    id: Number, internal identificator
    created: Datetime, creation time and visual and sync identificator
    updated: Datetime, last update time, to sync the latest udpate
    text: String, encrypted textual entry
}

AES-256 algorithm is used for encryption. A passphrase is saved for the session time to decrypt existing and encrypt updated records. Decrypted text is only shown to the user. Database has only encrypted text. A SHA-256 hash of the passphrase is presisted to guide the user against the incorrect and inconsistent passphrase. A workspace is locked after timeout and other conditions; this erases local copy of the passphrase.

Views are organazed into states with ui-router. The main one shows a list of records and allows to read and edit a record.

Backup and sync are done with Dropbox. Records are split to yearly chunks and saved to JSON files to allow for relatively small units for faster upload and download.

Development

Start with:

cd dayary
# Consider adding: --omit=dev
npm install
python -m http.server --bind 127.0.0.1 3000

Then navigate to http://127.0.0.1:3000 in the browser. The choice of port, 3000 is deliberate, as Dropbox will redirect back to this address after authentication.

Powered by

The tool was built with the help of the following wonderful:

• Services: GitHub (including GitHub Pages), Dropbox
• Tools: Chrome, npm, bower, jshint
• Frameworks: Angular.js, Jasmine.js, node.js
• Libraries: bootstrap, font-awesome, ui-router, Moment.js, Underscore.js, dropbox.js, sqlite3, cryptojslib