Possibility to dump tree as json

[mieczkowski]

Hello,

I need possibility to dump tree to list of records (to store in DB for example), so I've added two methods:

• MarshalJSON to marshal tree (separated ipv4 and ipv6 keys) to json.

• DumpList to build custom json struct, use for example in database storage, or for debug purpose.

Test data is taken from stringify_test.go.

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• -2 of 36 (94.44%) changed or added relevant lines in 1 file are covered.
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• Overall coverage increased (+0.6%) to 94.894%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
jsonify.go	34	36	94.44%

Files with Coverage Reduction	New Missed Lines	%
stringify.go	12	85.59%

Totals
Change from base Build 7790117356:	0.6%
Covered Lines:	762
Relevant Lines:	803

---

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[gaissmai]

@mieczkowski thanks for contribution. Since you didn't open an issue before, I updated the main branch already by accident. Please rebase your PR on it.
I'm not happy with the public DumpList, please make it private and please check again the docstrings, I've seen at least one typo.
Best regards
Charly

... and by reading the code (well done!) I've just some minor remarks:

• rename dumpList to dumpListRec
• rename DumpList to dumpList
• please change the signatures without error results, there is no error generating code in these fuctions

just my five cents

[mieczkowski]

Good catch with errors handling - I've simplified code. However I can not test one error check, because there is no chance to simulate this error, except some I/O errors inside json.Marshal:

buf, err := json.Marshal(result)
if err != nil {
	return nil, err
}

Please consider leaving DumpList as public function. In my case I have list of subnets in DB (flat list). I need to rebuild tree after every operation on this with some validations, and:

1. Marshaling into json is helpful for rest api (returning sorted tree to frontend)
2. DumpList is helpful for add/remove operations and update DB

Without this method I need to marshal json and parse it into map[string] . Unnecessary waste of resources and without it I will end up with fork - and I don't want that ;)

[gaissmai]

please see my inline comment to DumpList

[gaissmai]

still a typo in this public docstring and a missing dot at end of line. If this method has to be public, please invest more time to find a clear description or spend an extra test or maybe a dumplist_example_test.

[mieczkowski]

I've fixed both docstrings.

I don't think that we need separated tests for DumpList. It will be duplicate of json tests.

[gaissmai]

The test for DumpList was not meant for testing, just to better explain the public method, but I can live without or add it myself later.

Two more small remarks:

• public type ListElement needs a docstring.
• please rename field Cidr to CIDR, for golang naming convention, like HTTP and not Http
  Regards
  Charly

[mieczkowski]

Done

[gaissmai]

What do you think about the following naming:

type DumpListElement[V any] struct {}
func (t *Table[V]) DumpList(is4 bool) []DumpListElement[V]

background: the type only deals with dumping and marshaling, nothing with the real bart-Table algo.
or maybe: DumpListNode, since it's a recursive datastructure

[mieczkowski]

What do you think about the following naming:

type DumpListElement[V any] struct {}
func (t *Table[V]) DumpList(is4 bool) []DumpListElement[V]

background: the type only deals with dumping and marshaling, nothing with the real bart-Table algo. or maybe: DumpListNode, since it's a recursive datastructure

I vote for DumpListNode , looks better than element since it's a tree :)

[gaissmai]

merged, thanks for contribution