Script for finding and executing an outbox message from the flextesa smart-rollup sandbox running in a docker container.

withdrawal.sh

    #!/bin/bash

    # This script will execute the outbox message of a smart rollup contract.
    # It's intended to be used with a Flextesa sandbox within a Docker container.

    set -e
    set -o pipefail

    container=${container_name:-"my-sandbox"} # Name of the Docker container
    time_bb=${block_time:-2}                  # Time between blocks in seconds
    proto=${protocol:-"Proxford"}             # Tezos protocol hash

    export TEZOS_CLIENT_UNSAFE_DISABLE_DISCLAIMER="YES" # Remove the "Test Net" warning.

    say() { printf "[Withdrawal:] $@" >&2; }

    # Execute octez-client commands within the container.
    cli () {
        docker exec "$container" octez-client --protocol "$proto" "$@"
    }

    # RPC calls pointed at the octez-smart-rollup-node.
    soru_rpc () {
      cli -E "http://localhost:20002" rpc get "$@"
    }

    # Get the smart-rollup address.
    get_sr_addr() {
        sr_addr="$(cli list known smart rollups | grep 'evm:' | awk '{print $2}')"
        if [ -z "$sr_addr" ]; then
            say 'Error: Empty output from octez-client list known smart rollups.\n'
        else
        echo "$sr_addr"
        fi
    }
    SR_ADDR="$(get_sr_addr)"
    export SR_ADDR

    # Find a message starting from the current block and searching back a specified number of levels.
    # This assumes that the first message found is the one you want to execute.
    find_message() {
        # Get the current level of the chain.
        level="$(cli rpc get "/chains/main/blocks/head/metadata" | jq .level_info.level)"
        if [ -z "$level" ]; then
            say 'Error: No "level_info" found from octez-client rpc get "/chains/main/blocks/head/metadata".\n'
            return 1  # Failure
        fi

        found=false
        counter=0
        max="$1"
        # Search back a $max number of levels for a non-empty rollup outbox message.
        while [ "$found" = "false" ] && [ "$counter" -lt "$max" ]; do
            msg="$(soru_rpc "/global/block/head/outbox/${level}/messages")"
            case "$msg" in
                *'[]'*)
                    level=$((level - 1))
                    ;;
                *)
                    found=true
                    ;;
            esac
            counter=$((counter + 1))
        done

        if [ "$found" = "true" ]; then
            echo "$level" # The block level at which a message was found.
        else
            say "No messages in the last %s levels.\n" "$1"
            return 1
        fi
    }

    # Wait for the commitment at `level` to be cemented allowing the outbox message to become available for execution.
    cemented_message() {
        level="$1" # The level containing the outbox message.
        cemented=false
        counter=0
        max=90 # max nuber of tries. There is some buffer incase the blocks are slow

        # Query cemented outbox until the message arrives or $max reached.
        while [ "$cemented" = "false" ] && [ "$counter" -lt "$max" ]; do
            msg="$(soru_rpc "/global/block/cemented/outbox/${level}/messages")"
            case "$msg" in
                *'[]'*)
                    ;;
                *)
                    say "The commitment at level %s is cemented.\n" "$level"
                    return 0 # Success
                    ;;
            esac
            sleep "$time_bb"
            counter=$((counter + 1))
        done

        say "Message never cemented at level %s.\n" "$level"
        return 1  # Failure
    }

    # Execute the outbox at a specified level.
    execute_outbox() {
        level="$1"
        json="$(soru_rpc "/global/block/head/helpers/proofs/outbox/${level}/messages?index=0")"
        proof="$(echo "$json" | jq -r '.proof' | sed 's/^/0x/')" # Prepend "0x" because the octez-client expects a hexadecimal value.
        commit="$(echo "$json" | jq -r '.commitment')"

        cli execute outbox message of smart rollup "$SR_ADDR" \
            from alice for commitment hash "$commit" \
            and output proof "$proof" --burn-cap 1
    }

    # Run the entire sequence of operations in order.
    run () {
        say "Alice's starting balance: $(cli get balance for alice)\n"
        SEARCH_DEPTH=300
        say "Searching for the outbox message in the last %s levels...\n" "$SEARCH_DEPTH"
        MESSAGE_LEVEL=$(find_message "$SEARCH_DEPTH")
        say "The evm-rollup outbox message was found in the commit at level %s.\n" "$MESSAGE_LEVEL"
        say "Waiting for the commitment to cement...\n"
        cemented_message "$MESSAGE_LEVEL"
        say "Executing the outbox message...\n"
        execute_outbox "$MESSAGE_LEVEL"
        say "Alice's ending balance $(cli get balance for alice)\n"
    }


    { if [ "$1" = "" ]; then run; else "$@"; fi; }