Dealing with Errors and Empty Data

When downloading historical price data for stocks and other instruments using dukascopy-node, it is important to be aware that the library is dependent on external datafeed servers that may return empty responses or errors.

By default, dukascopy-node will throw an error if a request errors out, and will not make any retries if a request returns an empty response. However, the library provides built-in mechanisms to help you handle these situations.

Retrying Failed Requests

If a request for data errors out, you can use the --retries parameter (or retryCount for Node.js) to retry the request. The parameter specifies the number of retries to attempt before the library throws an error.

npx dukascopy-node -i usdcad -from 2023-05-11 -to 2023-05-12 -t tick -f csv --retries 15

Retrying Empty Responses

Sometimes a request returns a successful response, but with empty data. In such cases, you can use the --retry-on-empty parameter (or retryOnEmpty for Node.js) to retry the request until the response is no longer empty. This parameter works in conjunction with the --retries parameter and will also throw an error if the maximum number of retries is exhausted.

npx dukascopy-node -i usdcad -from 2023-05-11 -to 2023-05-12 -t tick -f csv --retries 15 --retry-on-empty

Handling Exhausted Retries

If you do not want an error to be thrown when the maximum number of retries is exhausted, you can use the --no-fail-after-retries parameter (or failAfterRetryCount for Node.js). This parameter prevents the library from throwing an error when the maximum number of retries is exhausted, and instead returns an empty response.

npx dukascopy-node -i usdcad -from 2023-05-11 -to 2023-05-12 -t tick -f csv --retries 15 --retry-on-empty --no-fail-after-retries