log additional information in exchanges

[chadwhitacre]

When we move money between Gittip and the outside world we call that an "exchange" and we record each such event in the exchanges table. Here's its schema:

=> \d exchanges
                                     Table "public.exchanges"
┌─────────────┬──────────────────────────┬────────────────────────────────────────────────────────┐
│   Column    │           Type           │                       Modifiers                        │
├─────────────┼──────────────────────────┼────────────────────────────────────────────────────────┤
│ id          │ integer                  │ not null default nextval('exchanges_id_seq'::regclass) │
│ timestamp   │ timestamp with time zone │ not null default now()                                 │
│ amount      │ numeric(35,2)            │ not null                                               │
│ fee         │ numeric(35,2)            │ not null                                               │
│ participant │ text                     │ not null                                               │
│ recorder    │ text                     │                                                        │
│ note        │ text                     │                                                        │
└─────────────┴──────────────────────────┴────────────────────────────────────────────────────────┘
Indexes:
    "exchanges_pkey" PRIMARY KEY, btree (id)
Foreign-key constraints:
    "exchanges_participant_fkey" FOREIGN KEY (participant) REFERENCES participants(username) ON UPDATE CASCADE ON DELETE RESTRICT
    "exchanges_recorder_fkey" FOREIGN KEY (recorder) REFERENCES participants(username) ON UPDATE CASCADE ON DELETE RESTRICT

The relationship between amount and fee is complicated and should be cleaned up. That's #2442.

The recorder and note fields are used when an admin manually enters an exchange.

What we need here is more information recorded during an exchange in order to aid debugging, e.g. on #2372. Exchanges involve API calls to Balanced (etc.). We should record detailed information about what API call was made and what the result was. We should also record what funding instrument was involved so that whether or not there is a failure we can make our reporting more accurate (#1681).

[chadwhitacre]

Maybe we use the JSON pg type to store the full result of the API call?

[chadwhitacre]

Balanced gives us detailed log info on all API requests, so if we're comfortable trusting Balanced as our datastore then we could simply store the URI on our side.

[chadwhitacre]

[chadwhitacre]

[chadwhitacre]

We at least need to locally store info that we need in order to present receipts and other history to the user.

[chadwhitacre]

This is blocking #1681.

[Changaco]

Even if we start logging additional information about exchanges it won't fix the past receipts (#1681). If we want to fix those we'll have to do lots of Balanced API queries to retrieve the information.

[chadwhitacre]

I think it's worth it to do the extra Balance API queries. It will be a one-time repair and this is fundamental: if we're not trustworthy with financial transactions then what are we worth?

[Changaco]

Added to the Balanced shutdown milestone.

[chadwhitacre]

if we're comfortable trusting Balanced as our datastore

😞

[chadwhitacre]

If we want to fix those we'll have to do lots of Balanced API queries to retrieve the information.

I downloaded all transactions in JSON format on gratipay/inside.gratipay.com#308 and uploaded them to https://github.com/gratipay/logs/tree/master/misc/308/raw/balanced/transactions.

[chadwhitacre]

We should also record what funding instrument was involved so that whether or not there is a failure we can make our reporting more accurate (#1681).

That's the route column, which we have now and need to use properly in #3839, which is blocked on #2779, which is blocked on #3822.

What we need here is more information recorded during an exchange in order to aid debugging, e.g. on #2372. Exchanges involve API calls to Balanced (etc.). We should record detailed information about what API call was made and what the result was.

This is the new ref column that was added in #3810 and should be cleaned up alongside route.

Closing this as done with ref.