Mutating with Input Object Types

In this video, we're gonna be running another mutation, but 0:00 this time with a different set of arguments. 0:03 Instead of only specifying scalar arguments, like title and tag line, 0:06 this time were gonna add a more complex object type called an input object. 0:11 Unlike scalars, input objects have their own nested properties, 0:17 which can be scalars or more input objects. 0:21 The endpoint we're using in this video is the add director to movie endpoint. 0:26 To see which arguments the add director to movie endpoint accepts, 0:31 let's scroll down in our back end editor to check out the schema under type deps. 0:35 Looks like it takes a movie ID of type ID, which in this case just means a string. 0:43 It also takes a director object of type director input. 0:48 If we scroll up to check out the director input type, 0:53 we can see that the only field that it contains is the name field. 0:56 Going back to our addDirectorToMovie endpoint, 1:00 you can see that there's a colon after the arguments list. 1:03 This colon indicates what type of object will be returned from this mutation. 1:06 Just like the create movie endpoint, 1:12 addDirectorToMovie also returns a movie object. 1:14 To define the input object we're going to use the query variables pane in Launchpad, 1:18 right below the query editor pane. 1:24 This is pure JSON, so we just need to name the argument. 1:26 In this case, that will be directorToAdd. 1:30 Followed by a colon and curly braces. 1:36 Inside the curly braces, add the only required director property which is name. 1:40 I'm gonna go ahead and use my name for the value, but you can use your name or 1:47 any other name you see fit. 1:51 Now, let's write the mutation. 1:53 Since we are passing in a query variable, we need to let GraphQL know at the top 1:58 of our mutation declaration what type of variabless being passed in. 2:04 The way that we do this is after the mutation declaration, 2:09 we add parenthesis then we put in a dollar sign followed by the name of 2:13 the query variable we'll be using, which in this case is directorToAdd. 2:17 To let the endpoint know that this is actually the type of argument that it 2:23 requires, we need to specify that our query variable is of type director input. 2:29 And we'll go ahead and put an exclamation point to let them know that it's required. 2:37 Now for the addDirectorToMovie endpoint we can plug in the arguments. 2:44 For movieId, let's go ahead and 2:51 use movie_0, that should be the first movie in our list. 2:55 And then for director, we're just gonna go ahead and 3:00 reference that directorToAdd variable that we declared at the top. 3:04 Note that again we've included this dollar sign before the variable name. 3:10 That's how GraphQL knows that we're using these query variables. 3:14 Just like every other operation we've run, 3:19 we need to specify which field we want to appear on the response. 3:22 We know that addDirectorToMovie returns a movie, so this time around we'll 3:26 return the title, the tagline and the directors list. 3:31 This will be a list of the directors and 3:38 should include the director that we've just added. 3:41 As we know director is not a scalar type, instead it's an object type. 3:45 Therefore we need to specify which fields we'd 3:50 like to see in those nested directors. 3:53 In our case, we're going to look for the ID in the name fields. 3:55 Go ahead and click play. 4:00 There we go. 4:03 We can see our title, our tagline, and our directors list. 4:04 And as you can see, our new director Isaac Lee Morris, has been added to the list. 4:12 And that's it, you've learned how to use mutations with both scalar and 4:18 input object types, which will wrap-up this stage. 4:22 In the next stage, 4:26 I'll go over some tricks you can use to make using GraphQL even simpler. 4:27