Dex2Com

Synchronize glucose data between Dexcom Share accounts across different regions.

Why This Project Exists

This tool was created to solve a specific problem: using the Omnipod 5 iPhone App with an Omnipod 5 PDM device outside the United States. The Omnipod 5 App is only available in the US and requires access to US-based Dexcom Share servers and the Glooko app's US infrastructure. For users outside the US, this creates a barrier to using their preferred diabetes management tools.

Dex2Com bridges this gap by automatically synchronizing glucose readings from a US Dexcom Share account to a European (or other region) Dexcom Share account. This enables users to maintain glucose data in both regions simultaneously, making it possible to use region-specific diabetes management applications that rely on Dexcom Share data.

While originally built for the Omnipod 5 use case, this tool can be used by anyone who needs to mirror glucose data between two separate Dexcom accounts, regardless of the reason.

Features

• Real-time glucose data synchronization between Dexcom Share accounts
• Support for US, EU/OUS, and JP Dexcom regions
• Automatic duplicate filtering to prevent data redundancy
• Daemon mode for continuous background synchronization
• Automatic session renewal on timeout for uninterrupted sync
• Connection testing to verify account credentials
• Configurable sync intervals and data limits
• Zero dependencies beyond the standard Node.js runtime

Requirements

• Node.js 18 or higher
• Two Dexcom Share accounts (source and destination)
• Dexcom Share feature enabled on both accounts

Installation

From npm

npm install -g dex2com

From source

git clone https://github.com/faymaz/dex2com.git
cd dex2com
npm install

Configuration

Create a .env file in your project directory:

cp .env.example .env

Edit the .env file with your account credentials:

# Source account (where data is read from)
SOURCE_USERNAME=your_us_username
SOURCE_PASSWORD=your_us_password
SOURCE_REGION=us

# Destination account (where data is written to)
DEST_USERNAME=your_eu_username
DEST_PASSWORD=your_eu_password
DEST_REGION=ous

# Synchronization settings
SYNC_INTERVAL_MINUTES=5
MAX_READINGS_PER_SYNC=12

Supported Regions

• us - United States (share2.dexcom.com)
• ous - Europe/International (shareous1.dexcom.com)
• jp - Japan

Usage

Test Connection

Verify that both accounts can be accessed successfully:

node index.js --test

One-Time Sync

Perform a single synchronization:

node index.js --once
# or
npm run sync

Daemon Mode

Run continuous synchronization in the background:

node index.js --daemon
# or
npm run daemon

Running as a System Service

For Linux systems using systemd, you can set up Dex2Com to run automatically at boot.

Create a service file at /etc/systemd/system/dex2com.service:

[Unit]
Description=Dex2Com Glucose Sync Service
After=network.target

[Service]
Type=simple
User=your_username
WorkingDirectory=/path/to/dex2com
ExecStart=/usr/bin/node index.js --daemon
Restart=always
RestartSec=10

[Install]
WantedBy=multi-user.target

Enable and start the service:

sudo systemctl enable dex2com
sudo systemctl start dex2com
sudo systemctl status dex2com

How It Works

Dex2Com operates in three steps:

1. Authentication: Logs into both source and destination Dexcom Share accounts
2. Data Retrieval: Fetches the latest glucose readings from the source account
3. Data Upload: Writes new readings to the destination account using a virtual receiver

The synchronization process respects the Dexcom API rate limits and only uploads readings that don't already exist in the destination account.

Example Output

Dex2Com v1.0.0 - Dexcom Share Account Sync
==========================================

[2024-01-15T10:30:00.000Z] [INFO] Starting Dex2Com daemon (interval: 5 minutes)
[2024-01-15T10:30:00.100Z] [INFO] Source: US -> Destination: OUS
[2024-01-15T10:30:01.500Z] [INFO] Registered receiver: DEX2COM0001
[2024-01-15T10:30:01.600Z] [INFO] Starting sync from US to OUS
[2024-01-15T10:30:02.000Z] [INFO] Read 3 readings from source
[2024-01-15T10:30:02.100Z] [INFO] 3 new readings to sync
[2024-01-15T10:30:03.000Z] [INFO] Successfully synced 3 readings
[2024-01-15T10:30:03.100Z] [INFO] Latest: 125 mg/dL (Flat) at 10:29:00

Troubleshooting

Invalid Credentials Error

• Verify your username and password are correct
• Ensure you can log into the Dexcom Share mobile app with the same credentials
• Check that you're using the correct region code

No Readings Available

• Confirm that Share is enabled on the source account
• Verify that your Dexcom device is actively transmitting data
• Check that readings are visible in the Dexcom Share app

Data Not Appearing in Destination Account

• Ensure Share is enabled on the destination account
• Run node index.js --test to verify both connections work
• Check the logs for any error messages during sync

Session Timeout Errors

If you see "Session not active or timed out" errors in logs:

• The application will automatically detect and renew expired sessions
• No manual intervention required - the sync will resume automatically
• If errors persist, verify your credentials are still valid

Technical Details

API Endpoints

• Authentication: AuthenticatePublisherAccount
• Login: LoginPublisherAccountById
• Read: ReadPublisherLatestGlucoseValues
• Write: PostReceiverEgvRecords
• Register: ReplacePublisherAccountMonitoredReceiver

Data Format

Glucose readings use the Dexcom proprietary date format:

{
  "WT": "/Date(1705312140000)/",
  "ST": "/Date(1705312140000)/",
  "DT": "/Date(1705312140000+0300)/",
  "Value": 125,
  "Trend": "Flat"
}

Privacy and Security

• All credentials are stored locally in your .env file
• No data is sent to any third-party servers
• Communication occurs directly between your machine and Dexcom's official API servers
• Passwords are transmitted over HTTPS only

Contributing

Contributions are welcome! Please feel free to submit issues or pull requests on GitHub.

License

MIT License - see LICENSE file for details

Author

faymaz

Related Projects

• jsdexcom - JavaScript library for Dexcom Share API

Disclaimer

This is an unofficial tool and is not affiliated with, endorsed by, or connected to Dexcom, Inc. or Insulet Corporation. Use at your own risk. Always verify glucose readings with your primary monitoring device.