In ES, event data is not being stored as JSON objects but just as strings

[drozzy]

It seems like the event data is being sent as a string and not as json to event-store.
For JSON you need to set data_content_type of extreme lib to "1" (it is set to 0 by default):
https://github.com/exponentially/extreme/blob/5bc3b34a94bb8530964b674261b978910339c77c/lib/extreme.ex#L137

I'm not sure where you set this.
Here is my events in Gregg's event store sent by commanded (pay attention to the "data" element):

{
    "correlationId": "ccf88746-06ba-459f-b93a-9ccce1cebdf1",
    "readerPosition": {
        "$s": {
            "$ce-account": 6
        }
    },
    "events": [
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventType": "Elixir.Bank.Events.AccountOpened",
            "data": "{\"timestamp_utc\":1506096118,\"initial_balance\":0,\"client_id\":\"3324-john.oliver\",\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"7e083e9e-bcf6-4cc5-8cc8-47d84f14ec50\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 0
                }
            }
        },
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventNumber": 1,
            "eventType": "Elixir.Bank.Events.MoneyDeposited",
            "data": "{\"timestamp_utc\":1506096512,\"amount\":1000,\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"fc725dea-c9d9-4cb2-aa47-dcc0cc8ca59c\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 1
                }
            }
        },
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventNumber": 2,
            "eventType": "Elixir.Bank.Events.MoneyWithdrawn",
            "data": "{\"timestamp_utc\":1506096582,\"amount\":25,\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"87c5ffdf-d424-48df-878f-ce276265487a\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 2
                }
            }
        },
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventNumber": 3,
            "eventType": "Elixir.Bank.Events.MoneyDeposited",
            "data": "{\"timestamp_utc\":1506096699,\"amount\":33,\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"da047c54-7349-400b-a065-a9313413716c\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 3
                }
            }
        },
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventNumber": 4,
            "eventType": "Elixir.Bank.Events.MoneyWithdrawn",
            "data": "{\"timestamp_utc\":1506096699,\"amount\":661,\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"61df179b-03ef-40f5-90e7-e9852a0aa526\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 4
                }
            }
        },
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventNumber": 5,
            "eventType": "Elixir.Bank.Events.MoneyDeposited",
            "data": "{\"timestamp_utc\":1506096699,\"amount\":500,\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"2292148d-70ea-4885-b4cb-968070c2f2d2\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 5
                }
            }
        },
        {
            "eventStreamId": "account-333-121-568-3245",
            "eventNumber": 6,
            "eventType": "Elixir.Bank.Events.MoneyDeposited",
            "data": "{\"timestamp_utc\":1506096699,\"amount\":22,\"account_id\":\"333-121-568-3245\"}",
            "metadata": "{\"$correlationId\":\"fd6ac525-a7e6-450d-9781-f280245800f6\"}",
            "readerPosition": {
                "$s": {
                    "$ce-account": 6
                }
            }
        }
    ]
}

Any tips on how to hack it to work?

[slashdotdash]

Closing this issue and have opened one in the Commanded Extreme adapter project (#4).

Here's the source where the Commanded.EventStore.Adapters.Extreme sets data_content_type: 0 to append new events. You could try changing it, and the metadata_content_type, to see if that has any affect.

Pull request gladly accepted if that works!