如何在IOS中为Google App Engine端点启用可选参数

Question

I have created a backend API project and am successfully calling the API exposed by the endpoints within my App when no parameters are passed.

GTLQueryNewerAPI *query = [GTLQueryNewerAPI queryForMymodelList];

This method has been designed with an optional parameter. As seen in the generate Google API Discovery Service:

// Method: newerAPI.mymodel.list
//  Optional:
//   pupil: NSString
//  Authorization scope(s):
//   kGTLAuthScopeNewerAPIUserinfoEmail
// Fetches a GTLNewerAPIMyModelCollection.
+ (instancetype)queryForMymodelList;

I would like to pass a pupil parameter when calling the API but I am having difficulty doing so.

NSString *pupil = @"Test Name";
GTLServiceNewerAPI *service = [self helloworldService];
GTLQueryNewerAPI *query = [GTLQueryNewerAPI queryForMymodelList:(NSString*)pupil];

No known class method for selector 'queryForMymodelList:'

Answer 1

Becuase pupil is an optional parameter, it doesn't generate a constructor for it - putting it in the constructor would make it required for creating an instance of GTLQueryNewerAPI .

All you have to do is the following:

NSString *pupil = @"Test Name";
GTLServiceNewerAPI *service = [self helloworldService];
GTLQueryNewerAPI *query = [GTLQueryNewerAPI queryForMymodelList];
query.pupil = pupil;

You should see the pupil property declared in the header file for GTLQueryNewerAPI (usually something like the following:

@interface GTLQueryNewerAPI : GTLQuery
//
// Parameters valid on all methods.
//

// Selector specifying which fields to include in a partial response.
@property (nonatomic, copy) NSString *fields;

//
// Method-specific parameters; see the comments below for more information.
//
@property (nonatomic, copy) NSString *pupil;

...
@end

That pupil property, if so declared, is intended to be set when needed.