GET total_deposited + spender_leaf route completed + tests

[simzzz]

Questions :

• Should we add a different Error struct for the create_spendable_document() helper function like we did for the campaign routes?
• What will happen if an error is thrown after the new Spendable is inserted in DB (ex. during total_spent calculations) and should we worry about it?
• adapter.get_deposit() returns a deposit that uses BigNum instead of the UnifiedNum we need for spendable. How should we deal with that?
• NewStateuses BalancesMap which uses BigNum instead of UnifiedMap which uses UnifiedNum. How should we deal with that?

[elpiel]

Q: > adapter.get_deposit() returns a deposit that uses BigNum instead of the UnifiedNum we need for spendable. How should we deal with that?
A: Using the Deposit asset of the channel we should convert the BigNum to UnifiedNum based on the precision of the token.

Q: > NewState uses BalancesMap which uses BigNum instead of UnifiedMap which uses UnifiedNum. How should we deal with that?
A: It should use UnifiedNum. It just hasn't been changed yet.

I will answer the other 2 questions once I review the PR.

[elpiel]

Should we add a different Error struct for the create_spendable_document() helper function like we did for the campaign routes?
You would probably need a new Error struct. There's probably a nicer way for those errors instead of creating new structs for Error everywhere but for the time being create a new struct.
It will hold the A::AdapterError and PoolError.

What will happen if an error is thrown after the new Spendable is inserted in DB (ex. during total_spent calculations) and should we worry about it?

As for the total_spent there won't be an error as I mentioned in the review. We only return the new_state.balances.spenders.get(spender) there

Just approved, the PR was not ready with multiple TODOs

[elpiel]

Could you please add camelCase to both structs SpenderResponse & SpenderLeaf.
It's missing now

[elpiel]

• Also separate the Spender (to spender.rs) and the make the SpenderResponse { spender: Spender }

• For spender/all then we can use: AllSpendersReponse { spenders: HashMap<Address, Spender> } but later we will add pagination, so more fields will be added to the struct

• Spender { total_deposited, spender_leaf: SpenderLeaf } - please change total to total_deposited

Please note that: we have the address in the route /spender/:address, this is not true for the spender/all route, so we need include the Address (i.e. using the HashMap<Address, Spender>)

[elpiel]

Make sure that clippy passes the checks & run rustfmt