trezor-firmware/tools/build_protobuf

#!/bin/bash
set -e

cd "$(dirname "$0")"

# set up paths
INDEX="__init__.py"
GENPATH="../trezorlib/messages"
PROTO_PATH="../vendor/trezor-common/protob"
PROTO_FILES="types messages"

# set up temporary directory & cleanup
TMPDIR=$(mktemp -d)
function cleanup {
    rm -r $TMPDIR
}
trap cleanup EXIT

# set up pb2 outdir
PB2_OUT="$TMPDIR/pb2"
mkdir -p "$PB2_OUT"

# compile .proto files to python2 modules using google protobuf library
for file in $PROTO_FILES; do
    protoc --python_out="$PB2_OUT" -I/usr/include -I"$PROTO_PATH" "$PROTO_PATH/$file.proto"
done

# create index (__init__.py)
cat > "$TMPDIR/$INDEX" << EOF
# Automatically generated by pb2py

EOF

# convert google protobuf library to trezor's internal format
for file in $PROTO_FILES; do
    ./pb2py -P "trezorlib.protobuf" -p "$PB2_OUT" -l "$TMPDIR/$INDEX" "$file" "$TMPDIR"
done

# ensure $GENPATH exists and is empty of messages
mkdir -p "$GENPATH"
# only remove messages - there could possibly be other files not starting with capital letter
rm -f "$GENPATH"/[A-Z]*.py

# move generated files to the destination
# (this assumes $INDEX is *.py, otherwise we'd have to add $INDEX separately)
mv "$TMPDIR"/*.py "$GENPATH"

# the exit trap handles removing the tmp directory