Callback Chaining

The video tutorial covers the callback chaining pattern in Node.js, focusing on asynchronous operations. It explains how to chain callbacks to perform tasks in a specific order, such as geocoding an address and using the coordinates for a weather forecast. The tutorial also addresses error handling in callbacks and demonstrates how to use command line arguments to make the application more dynamic. Finally, it includes testing and finalizing the application to ensure it functions correctly.

What is the main issue with the current asynchronous operations in the Node.js code?

• They are synchronous and block the event loop.

• They do not return any data.

• They operate independently and dump responses to the console.

• They are dependent on each other.

What is the purpose of moving the forecast call into the geocode callback function?

• To make the code synchronous.

• To ensure forecast runs before geocode.

• To chain asynchronous operations and use geocode output as input for forecast.

• To improve the performance of the application.

What was the error in the initial implementation regarding latitude and longitude?

• Latitude and longitude were hardcoded.

• The order of latitude and longitude was reversed.

• Latitude and longitude were missing from the data.

• Latitude and longitude were not used.

How can errors in the geocode function be handled to prevent running the forecast call?

• By logging errors to a file.

• By using a condition to check for errors and returning early.

• By using a try-catch block.

• By ignoring the errors.

What is the benefit of using return statements in error handling?

• It logs the error to the console.

• It retries the operation.

• It stops the function execution after printing the error.

• It continues the function execution.

What is the purpose of allowing user input for location via command line arguments?

• To improve the performance of the application.

• To allow dynamic input without modifying the source code.

• To hardcode the location in the source code.

• To test the application with a single location.

Which property on the process object is used to access command line arguments?

• process.stdin

• process.stdout

• process.argv

• process.env

What should be done if no location is provided as a command line argument?

• Print a message asking for an address and do not run geocode.

• Run the geocode function with a default location.

• Exit the application immediately.

• Use the last searched location.

How can you test the application with a location that has two words?

• By enclosing the location in double quotes.

• By using a hyphen between the words.

• By separating the words with a comma.

• By using a single word location.

What is the expected output when the application runs successfully with a valid location?

• Both location and forecast data are printed.

• Only the forecast data is printed.

• Only the geocode data is printed.

• An error message is displayed.