gaiad export"UnmarshalJSON cannot decode empty bytes"

[kimurayu45z]

Summary of Bug

$ gaiad export

Error

UnmarshalJSON cannot decode empty bytes

Steps to Reproduce

docker

FROM golang:1.11.5

RUN mkdir -p $HOME/go/bin
ENV GOPATH=$HOME/go
ENV GOBIN=$GOPATH/bin
ENV PATH=$PATH:$GOBIN

RUN mkdir -p $GOPATH/src/github.com/cosmos && \
    cd $GOPATH/src/github.com/cosmos && \
    git clone https://github.com/cosmos/cosmos-sdk && \
    cd cosmos-sdk && git checkout master && \
    make tools && make get_vendor_deps && make install

and then

$ gaiad init test
$ gaiad export

---

For Admin Use

• Not duplicate issue
• Appropriate labels applied
• Appropriate contributors tagged
• Contributor assigned/self-assigned

[cwgoes]

This is expected, since you haven't actually written any state yet (you'll need to run gaiad start first).

[jackzampolin]

We should have a better error message here and maybe not panic.

[MarinX]

can we modify subspace.go functions to return error instead of panic()?
I can make a valid PR for it...

[jackzampolin]

@MarinX That would be a great PR! We would accept that. The core issue here was a broken isDBEmpty function which had an incorrect conditional. I've fixed that to eliminate this panic.