Add context field to sessions.

[dwedul-figure]

Description

Add a context field to the Session message.

Also add a write-session CLI command and standardize the Use lines for the metadata tx CLI commands based on the cobra documentation.

closes: #276

---

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• Wrote unit and integration tests
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• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #278 (54bce09) into main (8d84d0f) will increase coverage by 0.27%.
The diff coverage is 84.84%.

@@            Coverage Diff             @@
##             main     #278      +/-   ##
==========================================
+ Coverage   49.97%   50.24%   +0.27%     
==========================================
  Files         119      119              
  Lines       10931    11025      +94     
==========================================
+ Hits         5463     5540      +77     
- Misses       4930     4938       +8     
- Partials      538      547       +9     

Impacted Files	Coverage Δ
x/metadata/types/p8e.go	30.53% <50.00%> (+0.13%)	⬆️
x/metadata/client/cli/tx.go	79.49% <85.38%> (-0.03%)	⬇️
x/metadata/handler.go	30.50% <0.00%> (+5.08%)	⬆️

[piercetrey-figure]

@dwedul-figure I think we will need a way to set this context on the MsgP8eMemorializeContractRequest and have that be set on the session via the conversion

[dwedul-figure]

@dwedul-figure I think we will need a way to set this context on the MsgP8eMemorializeContractRequest and have that be set on the session via the conversion

Doh! Yup. Totally forgot that part. Fixed now though. I added it to the Contract message: MsgP8eMemorializeContractRequest.Contract.Context. It's an Any field there too, and it just gets straight up copied over into the Session.Context field.

[iramiller]

One thing to potentially look for is a validation function for that proto any type url ... there are restrictions on the values that are allowed in there per spec... but I wouldn't try to write your own if there isn't one easily usable within the protobuf SDK.

[iramiller]

A URL/resource name that uniquely identifies the type of the serialized
protocol buffer message. This string must contain at least
one "/" character. The last segment of the URL's path must represent
the fully qualified name of the type (as in
path/google.protobuf.Duration). The name should be in a canonical form
(e.g., leading "." is not accepted).

In practice, teams usually precompile into the binary all types that they
expect it to use in the context of Any. However, for URLs which use the
scheme http, https, or no scheme, one can optionally set up a type
server that maps type URLs to message definitions as follows:

• If no scheme is provided, https is assumed.
• An HTTP GET on the URL must yield a [google.protobuf.Type][]
  value in binary format, or produce an error.
• Applications are allowed to cache lookup results based on the
  URL, or have them precompiled into a binary to avoid any
  lookup. Therefore, binary compatibility needs to be preserved
  on changes to types. (Use versioned type names to manage
  breaking changes.)

Note: this functionality is not currently available in the official
protobuf release, and it is not used for type URLs beginning with
type.googleapis.com.

Schemes other than http, https (or the empty scheme) might be
used with implementation specific semantics.

source: https://github.com/protocolbuffers/protobuf/blob/master/src/google/protobuf/any.proto

[piercetrey-figure]

I think I am running into issues when sending an Any value related to the stuff @iramiller mentioned above. I have tried several different ways (different prefixes, setting the any type url to github.com/provenance-io/provenance/x/metadata/types/p8e.UUID thinking maybe I had to use the go_package version) and seem to always get something like UNKNOWN: unable to resolve type URL /provenance.metadata.v1.p8e.UUID: tx parse error: invalid request.

Initially I was using a proto from within p8e, but then switched to this UUID proto that is present in the provenance p8e protos, hoping that it would resolve, but no luck so far.

Is there another way I should be specifying the Any type url?

[dwedul-figure]

Note for the future: The Cosmos SDK was trying to do some automatic validation of the Any field and failing because it couldn't find the TypeURLs being provided. So we decided to just use a byte array for the Context instead. Since the Session already is already associated with a process, it shouldn't have to tell others what the Context is.

[channa-figure]

LGTM, I like the edits to the cobra commands.