Ethereum 2.0 and Bitcoined: Overdependence Warning
In the rapidly evolving world of Ethereum 2.0, many developers have overlooked a simple but important step. The lines var exp = request('bitcore-explorers'); and var btc = request('bitcore-lib'); generate an error known as “More than one instance of bitcore-lib found”. This warning is a timely reminder that you need to be careful when importing libraries into your code.
problem
At first glance, these lines seem harmless. Two instances of the “bitcore” library are imported: “exp” and “btc”. However, this causes problems in the way JavaScript handles imports. When multiple libraries are imported in the same scope (i.e. module), it can lead to conflicts and errors.
Reason
In Node.js, when a library is needed, it checks to see if that library is already in use in the current scope. If another instance of the same library is found, an error message is thrown. This is known as “more than one instance” or “double import”.
To illustrate this, imagine two developers working on the same project:
- Developer A uses “bitcore-explorers” and “bitcore-lib” in his code.
- Developer B uses “bitcore-explorers” and “other-bitcore-lib”.
In this scenario, both developers are using the same instance of “bitcore”, which would cause a conflict. This is exactly what happens when we encounter the “More than one instance” error.
Solution
To resolve this issue, developers should follow best practices for importing libraries into their code:
- Use the exact name of the library (e.g. “bitcore-explorers” instead of “bitcore-lib”). This ensures that each import is unique and not duplicated.
- Avoid importing multiple instances of the same library in the same scope. Instead, consider refactoring your code to reduce dependencies.
Solution
You can fix this issue in our original example as follows:
var exp = require('
var btc = require('bitcore-lib');
By using the exact library name and avoiding duplicate imports, we can resolve the “More than one instance of bitcore-lib found” error.
Conclusion
As developers continue to build and maintain Ethereum 2.0 projects, it is important to be aware of library dependencies and import them correctly. By following best practices for importing libraries, you can avoid conflicts and ensure that your code remains stable and reliable. Remember: a simple oversight can lead to a more complex debugging process, so take the time to ensure that your imports are accurate.
