Support Tracing for Interservice gRPC calls

[coolwednesday]

Description:

• Prerequisite to closing Support Tracing in Interservice gRPC Calls #1392
• This PR adds a check to verify if the incoming metadata for gRPC has traceID and spanID. If present then the span created is a child span of the existing span to ensure proper tracing in interservice gRPC calls.
• The next step would be to develop the gofr-cli command that gives boilerplate code to add trace-id and span-id to the sent context's metadata.
• Further changes have been initiated in gofr-cli : "gofr wrap grpc client" to add tracing in inter-service gRPC Calls gofr-cli#26
  

Checklist:

• I have formatted my code using goimport and golangci-lint.
• All new code is covered by unit tests.
• This PR does not decrease the overall code coverage.
• I have reviewed the code comments and documentation for clarity.

Thank you for your contribution!

[aryanmehrotra]

1. Readme can be update either to refer the docs at gofr.dev/docs such that user can understand how these files are created.

2. Can we structure the examples in a better way -
   For example, for interservice http communication we dont have 2 examples.
   one way could be to have grpc and inside that we have two separate directories for a client and a server

[aryanmehrotra]

Logs needs to be fixed - BADWIDTH

Metadata should also contain the correaltionID - can be part of different issue ticket

When an external request is made - we should also log it similar to interservice http calls - can be part of a different ticket

[coolwednesday]

Logs needs to be fixed - BADWIDTH

Metadata should also contain the correaltionID - can be part of different issue ticket

When an external request is made - we should also log it similar to interservice http calls - can be part of a different ticket

In my implementation, I am only adding correlation ID that is the traceID, when the user actually initiates a call using gofr-CLI's generated gRPC Client. So only incoming context, while sending request carries metadata and none of the corresponding response/outgoing context include correlation ID in the metadata.

So, is it necessary in any case to have metadata with correlation ID in the outgoing context received ?

[ccoVeille]

I'm a bit surprised to see my recent commits I made in this PR.

It looks like to me you had to fight conflicts at some points. You apparently sorted them. 👍

I'm used to rebase-only workflow. Maybe it's OK in a merge-workflow 🤔 🤷

But I prefer to report it

[coolwednesday]

As there are multiple changes in files ... that are not related to the PR itself. I will be closing the PR and creating a new one.

Link to the new PR : #1408