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In this video we'll handle HTTP errors.
Documentation
STATUS_CODES
The STATUS_CODES array is not on the https object. STATUS_CODES can be found on the http object. To include the STATUS_CODES use the following code:
const http = require('http');
http.STATUS_CODES;
We've assumed so far that each of the API responses will be OK. 0:00 In other words, have the HTTP status code of 200. 0:05 There are other status codes that an API endpoint can have. 0:09 Maybe there's errors in the code actually running on the server where the endpoint 0:13 is happening. 0:17 That's when you'd get a 500 error or internal server error. 0:17 Or maybe the API endpoint has been updated and has moved somewhere else. 0:22 You'd get the status code of 301. 0:26 If the endpoint is incorrect or has removed completely, 0:29 you'd get the HTTP status code of 404, not found. 0:33 Let's handle all status codes that aren't 200. 0:39 If the response .statusCode is equal 0:43 to 200, we want to do the parsing. 0:48 If the status code isn't 200, 1:02 we want to printout an error message for the status code. 1:06 So let's create a new 1:12 statusCodeError by creating 1:17 a new Error object, 1:22 with the message of a template string saying, 1:26 There was an error getting 1:35 the profile for ${username}. 1:41 Then we can add the status code in brackets. 1:52 We can print the error using the printError method that 1:59 we created earlier, passing in statusCodeError. 2:04 Save the file and open up the console. 2:11 And let's try and run node app.js chalkers-not. 2:15 And there's something wrong in my code. 2:24 I didn't close my else statement. 2:32 Run it again, and 2:38 we get the message there was an error getting the profile for chalkers-not, 2:43 with the status code of 404, not found. 2:47 You may know what 404 is being a web developer, and 2:51 you've probably seen it on many a site. 2:55 But what if the error was something else? 2:59 Is there a way to translate these error codes into something a human can 3:02 easily understand? 3:07 The HTTP module has a statusCodes object that 3:08 returns an English string from a status code. 3:13 Remember that we need to include the module at the top. 3:24 Let's try again, Awesome, it says not found. 3:46 Let's walk chalkers-not back to chalkers to make sure we haven't broken anything. 3:55 We haven't, cool. 4:02 Now that we've handled all the errors, 4:05 why not improve the messages that are generated by the printError function? 4:07 When you're done, I'll see you in the next video, and 4:11 I'll show you some techniques for organizing your code. 4:14
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