initial commit for leaf setters

[adibrastegarnia]

Initial commit for adding leaf setters

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[adibrastegarnia]

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[coveralls]

Coverage decreased (-0.2%) to 91.014% when pulling fa4bf01 on adibrastegarnia:add-leaf-setters into 0c7dd99 on openconfig:master.

[coveralls]

Coverage decreased (-0.2%) to 91.004% when pulling da31991 on adibrastegarnia:add-leaf-setters into 0c7dd99 on openconfig:master.

[adibrastegarnia]

@robshakir
I started to add leaf setters to the list of helper functions. Would you please take a look so far and give me your comments?

[adibrastegarnia]

@robshakir
In addition, I am getting a compile error on my end but I don't know how I pass all of the checks:
generator/generator.go:255:23: unknown field 'GenerateLeafSetters' in struct literal of type ygen.GoOpts

I shouldn't get the error because I already defined it but I don't know why it happens

P.S. Resolved

[adibrastegarnia]

@robshakir
I assume that setter function does not return anything if I need to return error or ok or a value please let me know. I tested the patch and it looks like that is working but that would be great if you check it as well.

[robshakir]

Thanks for the contribution, there are some technical issues with this change that I've pointed out in the review.

Additionally, there's no unit testing for this change -- please add tests that both check the generated sets of methods are correct for the individual code, as well as an integration test that does this across a real input module (integration test with goyang). You can see some examples of these in TestSimpleStructs in codegen_test.go.

Also, please let's add a test to schema_tests in this package that tests more than just string fields.

Happy to discuss this design more if there's more info required as to the implementation here.

Thanks!
r.

[robshakir]

I'm not sure that you can just take a string as an argument, there are different types of fields that we have within the generated structs. Given that this is the case, we need to handle different inputs here. Determining the type that is needed should likely be from the input type that is in the generatedLeafSetter that you created. There are some other details that you'll need though, such as the name of the generated union, such that you can call To_XXX for these types.

[adibrastegarnia]

@robshakir
Thanks for your comments. That is a good point. I will start working on it but before that what types you would suggest to support? I will let you know if I have more questions.

[adibrastegarnia]

I think I figured that out.

[adibrastegarnia]

@robshakir

May I ask you how do you generate the expected output for the testcases? It says the following but it is not clear for me:
This package was generated by codegen-tests
using the following YANG input files: .....

[adibrastegarnia]

@robshakir

Please take a look at this code and I think it handles any type. Please let me know what you think. I also have a test case ready but I am not sure how do you generate the expected output in advance.

// goLeafSetterTemplate defines a template for a function that, for a
	// particular leaf, generates a setter method.
	goLeafSetterTemplate = `
// Set{{ .Name }} sets the value of the leaf {{ .Name }} from the {{ .Receiver }}
// struct. 
func (t *{{ .Receiver }}) Set{{ .Name }}(val interface{}) {
	if t == nil || val == nil {
		return
	}
	t.{{ .Name }} = ygot.ToPtr(val).(*{{ .Type }})
}

`

[robshakir]

Same comment as above re: whether you can use string.

This likely highlights a test coverage gap -- we should add tests to schema_tests which give an integration test against a YANG model that has >1 different field type.