Mattermost-server: Add KVListWithOptions to p.Helpers

[mattermod]

Often, plugins need to find all keys of a type.

Suggest implementing

func (h *Helpers) KVListAll(options ...Options) ([]string, error) ([]string, error)

For now there should be two options:

• Prefix(prefix string)
• WithChecker(f func (key string) (continue bool, err error))

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JIRA: https://mattermost.atlassian.net/browse/MM-19732

[a8uhnf]

I want to help with this.

[hanzei]

Thanks @a8uhnf :+1:

[hanzei]

@levb What do you think about changing the signature to KVListPrefix(prefix string, page, perPage int) to be consistent with our other API methods?

[levb]

@hanzei the whole point of this helper is to enumerate the entire set of keys of a type, without having to bother with the paging. 1/5 paging should be internal to the implementation. An overall limit of items to return should be enough. Maybe KVListAllWithPrefix?

I also contemplated a KVPrefixDo that would take a function, but decided against it for simplicity.

[RajatVaryani]

Often, plugins need to find all keys of a type.

@levb Can you please point me to an example plugin where this is required?

[levb]

@RajatVaryani Here's a pending PR, this request came out of it. It has 2 examples, grep for KVList, https://github.com/mattermost/mattermost-plugin-jira/pull/351/files#diff-3b02caad0024138fae666f1168b4d0cdR487.

This (first) example performs extra filtering, thus my comment about a KVPrefixDo being (maybe) a better way to express the functionality. 0/5 maybe implement them both?

[hanzei]

@hanzei the whole point of this helper is to enumerate the entire set of keys of a type, without having to bother with the paging. 1/5 paging should be internal to the implementation. An overall limit of items to return should be enough. Maybe KVListAllWithPrefix?

I agree and like KVListAllWithPrefix. What is the use case for a limit?

[levb]

@hanzei Made me think, I agree, let's simplify to func (h *Helpers) KVListAllWithPrefix(prefix string) (keys []string, err error).

Opinion on a supplemental/underlying func (h *Helpers) KVDoWithPrefix(prefix string, func (key string) (continue bool, err error)) error?

[hanzei]

:+1: func (h *Helpers) KVListAllWithPrefix(prefix string) (keys []string, err error)

The name KVDoWithPrefix confuses me. What does the Do mean? Is it a KVListAllWithChecker?

Maybe we want a KVListAll(options ...Options) ([]string, error) and support various options like Prefix(prefix string) or WithChecker(f func (key string) (continue bool, err error)). What do you think?

[levb]

👍 to options in this use-case! KVListWithOptions FTW.

[hanzei]

@a8uhnf Do you have any questions? Is the ticket clear to you?

[jasonblais]

Hi @a8uhnf, let us know if you're still open to working on this one? Let us know if you have any questions!

In the meantime, I'll open this up for grabs :)

[dlclark]

I'd like to help out on this one.

[jasonblais]

Awesome, thank you @dlclark! Let us know if you have any questions

[dlclark]

For this ticket is there an expectation of refactoring the commit mentioned by @levb (https://github.com/mattermost/mattermost-plugin-jira/pull/351/files#diff-3b02caad0024138fae666f1168b4d0cdR487) to use the new functionality?

Left to my own devices I'd think it'd be a separate ticket, but since I'm new here I don't want to assume too much.

[hanzei]

It would be great, if you would refactor the code in the jira plugin. But you'r PR alone is great, there is no pressure to do more.

[levb]

2/5 @dlclark file a new issue https://github.com/mattermost/mattermost-plugin-jira/issues/new, it's a great starter ticket for someone else? And you'll get the pleasure of being notified when someone uses the code you committed? :)

[AGMETEOR]

Currently making an attempt to use code from this PR here. So far so good :)