another updated chain-spec script

polkadot/scripts/update-chain-spec-with-fast-rococo.sh

@@ -0,0 +1,63 @@
+#!/bin/bash -eu
+
+CURRENT_DIR=$(pwd)
+
+usage() {
+  echo "usage $0 docker-image epoch-duration [options]"
+  echo " -c chain-name - base chain-spec to be used [default: westend-staging)"
+  exit -1
+}
+
+if [ "$#" -lt 2 ]; then
+  usage
+fi
+
+# docker image to be used
+DOCKER_IMAGE=$1
+EPOCH_DURATION_IN_BLOCKS=$2
+
+shift 2
+
+CHAIN_NAME="westend-staging"
+
+while getopts "x" o; do
+    case "${o}" in
+        c)
+            CHAIN_NAME=${OPTARG}
+            ;;
+        *)
+            usage
+            ;;
+    esac
+done
+
+if [ -z $DOCKER_IMAGE ]; then
+  usage
+fi
+
+OUTPUT_ROOT_DIR=exported-runtimes/
+
+# polkadot command:
+POLKADOT_CMD="docker run --rm -v $CURRENT_DIR:/dir -w /dir $DOCKER_IMAGE"
+
+# extract rococo runtime with adjusted epoch diration from docker image
+docker export $(docker create $DOCKER_IMAGE) | \
+  tar --transform="s|polkadot/runtimes/|$OUTPUT_ROOT_DIR/|" -xf - polkadot/runtimes/rococo-runtime-$EPOCH_DURATION_IN_BLOCKS/rococo_runtime.wasm
+
+# path to extracted rococo runtime:
+WASM_RUNTIME_BLOB_PATH=$OUTPUT_ROOT_DIR/rococo-runtime-$EPOCH_DURATION_IN_BLOCKS/rococo_runtime.wasm
+
+# do hexdump of runtime:
+hexdump -v -e '/1 "%02x"' $WASM_RUNTIME_BLOB_PATH > $WASM_RUNTIME_BLOB_PATH.hex
+
+# get westend spec:
+$POLKADOT_CMD build-spec --chain $CHAIN_NAME > $CURRENT_DIR/wococo-source.json
+
+# replace runtime in chainspec with newly built runtime with overwritten epoch duration:
+jq --rawfile code $WASM_RUNTIME_BLOB_PATH.hex '.genesis.runtime.system.code = "0x" + $code' > $CURRENT_DIR/chainspec-nonraw.json < $CURRENT_DIR/wococo-source.json 
+
+# jq will write numbers in compact way with 1e+18, substrtate json parser dont support it. 
+sed 's/1e+18/1000000000000000000/' -i $CURRENT_DIR/chainspec-nonraw.json
+
+# generate raw
+$POLKADOT_CMD build-spec --chain ./chainspec-nonraw.json --raw > $CURRENT_DIR/chainspec-raw.json