Please follow the general troubleshooting steps first:

Update your protoc to the latest version
Update your copy of grpc-gateway to the latest version from github. with git fetch https://github.com/grpc-ecosystem/grpc-gateway master && git reset --hard FETCH_HEAD
Delete the protoc-gen-grpc-gateway and protoc-gen-swagger binary from your PATH, and install locally built binaries.

Bug reports:

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Steps you follow to reproduce the error:

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What did you expect to happen instead:

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What's your theory on why it isn't working:

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