README.md

Correlation Id

Correlations Id is used in distributed applications to trace requests across multiple services. This package provides a lightweight correlation id middlware. Request headers are checked for a correlation id. If found or generated, this correlation id is attached to the request context which can be used to access the current correlation id where it is required for logging etc. Based on middleware settings correlation id can be returned with response headers.

Install and update

go get -u github.com/dmytrohridin/correlation-id

Get Correlation Id value

To get correlation id value use FromContext function.

id := correlationid.FromContext(req.Context())

HeaderName setting

By default Correlation-Id key used as header name. Behavior can be overridden.

middleware := correlationid.New()
middleware.HeaderName = "Request-Id"

IdGenerator setting

By default google/uuid package is used for correlation id when Correlation-Id header is not included in request headers. Behavior can be overridden by applying a custom function.

middleware := correlationid.New()
middleware.IdGenerator = func() string {
    return "any_id"
}

IncludeInResponse setting

By default Correlation-Id is sent in response header. Behavior can be overridden.

middleware := correlationid.New()
middleware.IncludeInResponse = false

EnforceHeader setting

By default Correlation-Id is not required in request headers. Behavior can be overridden.

middleware := correlationid.New()
middleware.EnforceHeader = true

If header is enforced and client does not send it - BadRequest will be returned.