Add collection information

[arn-the-long-beard]

Well, I guess that we need to implement all the methods we find on Arangodb documentation for collection or maybe not.

Here is the todo list

• implement get_collection -> done previously in database::collection

• update base_url for collection and add doc to it -> done in previous PR

• implement collection::properties -> done in previous PR

• add unit test for properties -> done in previous PR

• add or update structures that match the information from the doc
  Should we add Option<T> on CollectionDetails or having new structures?

• implement document count

• add unit test for get count

• implement statistics

• add unit test for statistics

Should we do something about the shard stuff there and there ?

• implement revision id

Question : the response in Arangodb 3.7 and 3.6 are different for revision. What is the best way to handle that ?

• add unit test for revision id

• implement checksum for collection

• add unit test for checksum for collection

Should we add read all collections ?

[fMeow]

Why wrap the bool in Option? Can we use bool only?

[arn-the-long-beard]

Hey, I was thinking it was "optional" parameters, so I used options. But you are right, we could use only bool. I'll make the try with only bool and see how it looks like.

[arn-the-long-beard]

I updated with bool, the code is a bit shorter. Option was useless. It is better now :)

[arn-the-long-beard]

If you are OK with the structures I made, I will check the last checkbox. Since there is no inheritance in Rust and I am originally a typescript guy, I wasn't sure about the strategy. So I choose to make more structs instead of having a giant struct with many options.

I think that having good clear type is important, isn't it ?

[fMeow]

The structures are pretty good! Thank you SO much.

[arn-the-long-beard]

Cool ! You'r welcome :)

Then we are good to go !

[fMeow]

Here what we want is to add query to the requested url. So we may consider using the set_query method in url::Url.

let mut url = self.base_url.join("checksum").unwrap();
if with_revisions{
    url.set_query(Some("withRevisions=true"));
}
if with_data {
    url.set_query(Some("withData=true"));
}
// make request and serialize response
...

[arn-the-long-beard]

Hey ! Thank you ! I do not know why I did not use it in the first place.
It seems that set_query resets the query from the beginning, so I had to use url.query_pairs_mut() instead.

[fMeow]

Wow, I didn't know that. Thank you.

Actually with_revisions and with_data is bool, so we don't need to explicitly compare them to a bool. That's fine, never mind.

[fMeow]

Looks great. Ready to merge?

[arn-the-long-beard]

Yes :) It is good to go !