This project contains three aws lambda-functions.

• customers
• monthly-report
• transactions

All of the lambda-functions and dynamoDB-tables are created in the eu-central-1-region.

All of these functions have an api-gateway. customers and transaction offers a GET and POST endpoint. monthly-report only supports GET requests.

customers and transactions have a persistent dynamoDB storage.

Each of the projects contains a folder called test-requests, where scripts to test the api's reside.

For example:

./test-requests/get-customer.sh

# {"customerName":"Florian","customerAddress":"Vienna","customerIban":"1234"}

The customer lambda offers three endpoints.

Receives all customers.

Example:

curl https://3f9r4wfb01.execute-api.eu-central-1.amazonaws.com/production/customers

[
  {
    "customerName": "Florian",
    "customerAddress": "Vienna",
    "customerIban": "1234"
  },
  {
    "customerName": "Florian",
    "customerAddress": "Vienna",
    "customerIban": "2345"
  }
]

Receives the customer with the given iban. The iban is unique to the customer.

curl https://3f9r4wfb01.execute-api.eu-central-1.amazonaws.com/production/customers/1234

{
  "customerName": "Florian",
  "customerAddress": "Vienna",
  "customerIban": "1234"
}

Creates a customer with the given information.

curl -H "Content-Type: application/json" -X POST \
-d '{"name":"Florian", "address": "Vienna", "iban": "2345"}' \
https://3f9r4wfb01.execute-api.eu-central-1.amazonaws.com/production/customers

The customer lambda offers two endpoints.

Receives the transactions with the given debtors iban. A month and year can be used as optional query-parameters for the request to filter the transactions.

# Receives all transactions for the iban 1234
curl https://dkxj452gl7.execute-api.eu-central-1.amazonaws.com/production/transactions/1234

[
  {
    "transactionAmount": "132.50",
    "transactionDescription": "wage",
    "transactionDate": "2022-03-03",
    "transactionCreditorIban": "2345",
    "transactionDebtorIban": "1234",
    "transactionId": "2"
  },
  {
    "transactionAmount": "132.50",
    "transactionDescription": "wage",
    "transactionDate": "2022-03-03",
    "transactionCreditorIban": "1234",
    "transactionDebtorIban": "1234",
    "transactionId": "1"
  },
  {
    "transactionAmount": "132.50",
    "transactionDescription": "wage",
    "transactionDate": "2021-03-03",
    "transactionCreditorIban": "1234",
    "transactionDebtorIban": "1234",
    "transactionId": "3"
  }
]

# Receives all transactions for a specified month and year
curl https://dkxj452gl7.execute-api.eu-central-1.amazonaws.com/production/transactions/1234?year=2021&month=03

[
  {
    "transactionAmount": "132.50",
    "transactionDescription": "wage",
    "transactionDate": "2021-03-03",
    "transactionCreditorIban": "1234",
    "transactionDebtorIban": "1234",
    "transactionId": "3"
  }
]

Creates a transaction with the given information.

curl -H "Content-Type: application/json" -X POST \
-d '{"id": "99", "debtorIban":"1234", "creditorIban":"2345", "date": "2022-03-03", "amount": "132.50", "description": "wage"}' \
https://dkxj452gl7.execute-api.eu-central-1.amazonaws.com/production/transactions

The monthly-report lambda offers one endpoint.

Receives the monthly-report with the given debtors iban. A month and year can be used as optional query-parameters for the request, to filter the monthly-reports.

# Receives the monthly-report for a specified month and year
curl https://dkxj452gl7.execute-api.eu-central-1.amazonaws.com/production/transactions/1234?year=2021&month=03

{
  "report": {
    "customer": {
      "customerName": "Florian",
      "customerAddress": "Vienna",
      "customerIban": "1234"
    },
    "transactions": [
      {
        "transactionAmount": "132.50",
        "transactionDescription": "wage",
        "transactionDate": "2021-03-03",
        "transactionCreditorIban": "1234",
        "transactionDebtorIban": "1234",
        "transactionId": "3"
      }
    ]
  }
}

The service uses a dynamoDB with two tables. The tables are customers and transactions. The customer lambda creates customers-table and the transactions-lambda creates the transactions-lambda. The scripts for creating the table are stored the folder of the lambda. customers/create-customer-db.sh creates the customers-table and transactions/create-transaction-db.sh creates the transactions-table.

Run yarn install in the customers, monthly-report and transactions folder and the project is ready to be deployed to AWS.

Every package.json has the same three scripts:

• deploy-aws: Creates the function on AWS
• update-aws: Updates the code of the function on AWS
• release-aws: Sets the latest version on AWS to deploy.