First quick version of the readme:

Gocardless to YNAB Sync using Azure Functions & CosmosDB

GoCardlessToYnabSync is project to sync transactions from your bank to YNAB using the GoCarddless API, YNAB API and Azure as host.

Why:

I started this project because I was using a SaaS tool that did the same as this tool, but it stopped working for me after a week.. So I tried to create my personal "version" to sync transactions to YNAB that would costs less than the SaaS tool did while it is also customizable to my needs.

Limitations

This only syncs 1 bank account to 1 YNAB account. But it is possible to setup more Azure Functions to sync multiple bank accounts to the same YNAB account or a different once.

Getting Started

Requirements:

• .NET8
• Basic C# knownledge: to edit the code to fit your needs and get the correct information from the transactions.
• Basic Azure knownledge: to create resource so optimize cost and such.
• A YNAB account
• A GoCardless account

Happy flow of the sync logic

• Timed Function
  • => trigger GoCardlessSync Function
• GoCardlessSync Function
  • => Retrieve transactions from GoCardless
  • => Add to the CosmosDB
  • => Trigger YnabSync Function
• YnabSync Function
  • => Retrieve transactions that haven't been sent yet from the CosmosDB
  • => Send to YNAB
  • => Send mail to user (I added the sending of a email when new transactions are added to YNAB because the YNAB APP notifications don't seem to work on my phone)

Configuration

The URIs are used by the timed Azure function so it can trigger the Azure functions that do the logic

  "FunctionUris": {
    "GoCardlessSync": "",
    "YnabSync": ""
  },

Smpt configuration to send an email when new transaction are added to YNAB

  "Smpt": {
    "Host": "",
    "Port": 0,
    "Email": "",
    "Password": "",
    "SendTo": ""
  },

Storage account information to save the Transactions to keep track if they have been sent to YNAB or not.

  "CosmosDb": {
    "ConnectionString": "",
    "ContainerRequisitions": "Requisitions",
    "ContainerRequisitionsPartikionKey": "/requisitionId",
    "ContainerTransactions": "Transactions",
    "ContainerTransactionsPartitionKey": "/bookingDate",
    "Database": ""
  },

Gocardless Account information:

DaysInPastToRetrieve: How many days of data to retrieve from GoCardless.
SecretId/Secret: Get this from GoCardless by creating a secret.
BankId: See bottom of readme how to get your institution ID, not sure if this ID can be found another way.

  "GoCardless": {
    "DaysInPastToRetrieve": "7",
    "SecretId": "",
    "Secret": "",
    "BankId": ""
  },

YNAB account information Secret: API Key/Token from YNAB, Create a new personal access token here.
BudgetId: the GUID for the budget, this GUID can be found in the URI when you are viewing a budget https://app.ynab.com/#####-#####-#####-#####-#####/budget
AccountName: The name of the Account to add the transaction too.

  "Ynab": {
    "Secret": "",  // API key
    "BudgetId": "", // Budget ID, can be found in the URI
    "AccountName": ""
  }

Resource hosted on Azure

• App Service Plan
• Function App
• Storage Account
• Azure Cosmos DB account

Personally I currently have about a cost of 7 cents/month after using this for 3 months. The storage Account is the most costly resource, but I think the Storage/Storage Account could be more efficiently configured for this case.

Getting your Institution Id

Send a request as below using postman or any other API Client, the secret_id and secret_key are created here.

• METHOD: POST
• URI: https://bankaccountdata.gocardless.com/api/v2/token/new/
• Body: JSON

  {
    "secret_id": "####################",
    "secret_key": "############################################################################################################################################"
  }
  

This will give you the following JSON:

{
    "access": "ey############################################################################################################################################",
    "access_expires": 86400,
    "refresh": "ey############################################################################################################################################",
    "refresh_expires": 2592000
}

Using the access value, create the following reauest to get a list of all banks of a coutnry that are available in GoCardless and get the institution Id

• METHOD: GET
• URI: https://bankaccountdata.gocardless.com/api/v2/institutions/?country=**COUNTRY CODE** for example: be for Belgium or gb for Great Britain
• Headers: Authorization : Bearer ey############################################################################################################################################

This will return the following JSON:

[
    {
        "id": "XXXX_XXX_XXX",
        "name": "XXXXXX BANK",
        "bic": "XXXXXXXXX",
        "transaction_total_days": "540",
        "countries": [
            "GB"
        ],
        "logo": "https://storage.googleapis.com/xxxxxxxxxxxxxxxxxxx.png",
        "max_access_valid_for_days": "90"
    },
    ...
]

What you need is the value for the Id property and use that as the value for the GoCardless BankId configuration property.