Core development report #10: full steam on recurrent transfers

Hi ! I've been quite busy in the last week polishing the recurrent transfer feature, he's a rundown of everything that happened:

• https://gitlab.syncad.com/hive/hive/-/merge_requests/150/diffs?commit_id=25a0f0cf5ef84df457c3cd56a91a181ddb80b1c0 I have added a counter to the recurrent transfers so that if you fail to pay a recurrent transfer 10 consecutive times, the recurrent transfer is deleted, this helps keeping the blockchain clean of recurrent transfers that were created once and keep failing weighting the chain down for nothing, I also added a virtual operation for failed recurrent transfers, that way you can view all successful and failed recurrent transfers. by looking at the account history
• https://gitlab.syncad.com/hive/hive/-/merge_requests/150/diffs?commit_id=d8e1d547e36f9f50f5efbb3595b544fdd4323786 : I have added an end date parameter and fixed some issues that @blocktrade's team mentioned in their initial review: the idea of the end date is so that people can set and forget without fearing that their recurrent transfer will empty their accounts if they forget about it.
• https://gitlab.syncad.com/hive/hive/-/merge_requests/150/diffs?commit_id=6dca066814ff9a888c3759b09374f88c77970083 / https://gitlab.syncad.com/hive/hive/-/merge_requests/150/diffs?commit_id=1cf1698f9c83d4215e39cb51784ef8094f712feb
  / https://gitlab.syncad.com/hive/hive/-/merge_requests/150/diffs?commit_id=0b4ee43c58612c0e96d29fbff3b21b1a09930d14 Then it was time for some proper unit testing. this is especially important to detect some bugs now and in the future, if the unit testing covers everything, if someone breaks the feature as a side effect in the future we'll know. It's also a great way to double check everything. And I found a few bugs while doing the unit tests that I fixed.
• https://gitlab.syncad.com/hive/hive/-/merge_requests/150/diffs?commit_id=543349f520870425dfe6fa04659416a9211d8ebb Finally I added an api endpoint to see the recurrent transfers from an account to another called find_recurrent_transfers, and added it to cli_wallet

Here's a sample output:

[{
    "id": 0,
    "trigger_date": "2020-12-08T02:16:51",
    "from_id": 5,
    "from": "initminer",
    "to_id": 3,
    "to": "hive.fund",
    "amount": {
      "amount": "50000",
      "precision": 3,
      "nai": "@@000000013"
    },
    "memo": "recurrent t",
    "recurrence": 48,
    "consecutive_failures": 0,
    "end_date": "2021-05-05T05:08:33"
  },{
    "id": 1,
    "trigger_date": "2020-12-08T02:16:54",
    "from_id": 5,
    "from": "initminer",
    "to_id": 2,
    "to": "steem.dao",
    "amount": {
      "amount": "50000",
      "precision": 3,
      "nai": "@@000000013"
    },
    "memo": "recurrent t",
    "recurrence": 48,
    "consecutive_failures": 0,
    "end_date": "2021-05-05T05:08:33"
  }
]

Next I plan on doing more of a research task figuring out if we can expand the rc plugin to charge RC as it goes, so that we charge RC for an user every time he triggers a recurrent payment. It's a better UX than making him pay upfront the whole cost of all his future recurrent transfers.

If you have questions on some implementation details feel free to ask them :)

@howo