PoE state export

[alpe]

All modules cosmos-sdk support the state export/ import process where the persistent state data is converted into a json format and used in the (next) genesis file (for a new network) to setup the module again.
Note:

• there may be in-flight data as unclaimed rewards
• slashing and signed block data may be obsolete
• the new validator set may not be the same as the original one
• typically genesis validators are collected via gentx

What else do we need to export?
Contract state is persisted by wasm but not easy to read/maintain

[ethanfrey]

Is this the same as #95 ?

[ethanfrey]

One thought I had was to provide a way to "decode" the state of a contract if we know it is using storage-plus.

We can look at the key to see if it is Item or Map. We can try to parse the keys out and leave the values as json.RawMessage. This could end up like:

[
  {
    "type": "item",
    "name": "config",
    "value": { "some": "value" }
  },
  {
    "type": "map",
    "name": "votes",
    "schema": ["string", "u64"],
    "values": [
       {
          "key": ["cosmos1ckjhefiuhweughewoughuewghekw", 3]
          "value": {"yes": 34}
       },
       {
          "key": ["cosmos1fuewhfiuepofkafjewoighfe", 5]
          "value": {"no": 45}
       }
     ]
  }
]

I'm sure the rust team could help with some tooling like this. And then it would let us introspect all contract state.

One issue is how to store the data for IndexedMaps and SnapshotMaps (although I think Snapshots will be fine to export directly, we would want to rebuild indexes somehow to avoid them being invalid)

[ethanfrey]

@maurolacy curious as to your thoughts on the feasibility of this

[maurolacy]

@maurolacy curious as to your thoughts on the feasibility of this

I think that's possible. Our export query entry point will of course need to know about all the state in the contract. And compose the different structs into a big json. Something like a ExportResponse struct, that includes all the state present in the contract?

Also, would this require admin status / checks? I don't think so, as the contract info is public already. Perhaps for preventing denial of service / abuse?

[ethanfrey]

I think having an export query message and a import sudo message could make sense.

When we dump state, we export a contract specific format. And do not export the raw state.
When we import, we instantiate a contract with no data (default x/wasm behavior). Then we call the sudo entry point with import and the previously exported data.

There should be some flag for which contracts have that behavior. It could be a subset (or all) of the contracts created in bootstrap.go

[maurolacy]

Meeting notes: https://confio.slab.com/posts/tgrade-export-import-state-notes-a615f9gz

[alpe]

SDK support an export for zero height: https://github.com/cosmos/cosmos-sdk/blob/v0.45.2/simapp/export.go#L50 . This is disabled in the spike. Let's discuss how we want to tackle this with the PoE contracts or if they do it themselfs