feat: expose ChannelProvider from the gateway

[mblottiere]

We have a use case where given a Getway we need to query the ledger for some information (retrieving block from txID).

Being able to obtain the ChannelProvider is convenient since we can then create ledger.Client as needed. I wonder however if it is desirable to expose such a low level component. Maybe something like gateway.GetLedger(...) would be more appropriate? Let me know what you think.

[codecov[bot]]

Codecov Report

Merging #244 (d36373a) into main (965abe3) will not change coverage. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #244   +/-   ##
=======================================
  Coverage   76.23%   76.23%           
=======================================
  Files         193      193           
  Lines       14103    14103           
=======================================
  Hits        10752    10752           
  Misses       2384     2384           
  Partials      967      967           

Impacted Files	Coverage Δ
pkg/gateway/gateway.go	86.84% <100.00%> (ø)

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[bestbeforetoday]

You can get a block by transaction ID by evaluating the GetBlockByTxID transaction function on the qscc system chaincode. It takes two parameters: channel name and transaction ID. The implementation is here:

https://github.com/hyperledger/fabric/blob/cde0248c947f45e46bdf454ee5f6da42ebc79658/core/scc/qscc/query.go#L125-L126

This assumes that invocation of system chaincode works OK for fabric-sdk-go, which I haven't tried. It does work with fabric-gateway.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.