lavavisor/

LavaVisor

LavaVisor serves as a service manager for the Lava protocol application binaries. Its duty is to manage protocol versioning and coordinate seamless transitions to updated protocol versions.

When an upgrade becomes necessary, either because the current protocol version has dropped below the minimum version or not compliant with the recommended target version, LavaVisor’s responsibility begin. LavaVisor orchestrates the necessary upgrade process in an automated manner, ensuring that the protocol version is aligned with the current standards and capabilities set by the minimum and target versions.

Setup

make install-all → Creates lavavisor binary (under ~/go/bin/)

Prerequisites

Go version above than 1.19

Usage

Commands:

1- lavavisor init: Initializes LavaVisor for operation.

Optional Flags:

• --directory
• --auto-download
• --auto-start

Example usage: lavavisor init --auto-download

Prepares the local environment for the operation of LavaVisor. Here are the operations that lavavisor init performs:

1. Verifies the existence of the ./lavavisor directory for LavaVisor operations. If absent, it establishes the directory structure.
2. Sends a request to the Lava Network, retrieving the minimum and target protocol versions.
3. Using the acquired version, it searches for the corresponding protocol binary in .lavavisor/upgrades/<version-tag>/.
4. If the binary isn't found at the target location, it tries to download the binary from GitHub using the fetched version (note: the auto-download flag must be enabled).
5. Validates the fetched binary.
6. Verifies if a lavap binary already exists in the system path. If not, it copies the fetched binary to the system path.
7. Establishes a symbolic link between the fetched binary in .lavavisor/upgrades/<version-tag>/ and the protocol binary in the system path.

For a fully automated experience, usage of --auto-download flag is suggested

Wrap command

Wrap command is used for wrapping a single process in environment that cannot run with systemd (services) such as k8s or some containers.

The wrapping have two states.

1. running the command while having golang installed and prerequisites to build the lavap binary.

lavavisor wrap --cmd 'lavap rpcconsumer ./config/consumer_examples/lava_consumer.yml --from user1 --log_level debug --geolocation 1 --chain-id lava' --auto-download

1. running the command in lean pod environments that does not have golang / build dependencies and will fetch the binary from the github release page without building the binary and having a golang setup on the VM

• lavavisor pod does not require lavavisor init. as it will set everything on the go.

lavavisor pod --cmd 'lavap rpcconsumer ./config/consumer_examples/lava_consumer.yml --from user1 --log_level debug --geolocation 1 --chain-id lava'

running multiple wrap commands on the same VM

if you would like to run multiple wrappers on the same machine, you can set up one --auto-download process while the others are running with --auto-download disabled (default behavior) this will result with one process managing downloading and building while others just wait for the task to be completed.

Using keyring-backend os

If you are using keyring-backend os you will need to provide the lavavisor (wrap/pod commands only) with a keyring-backend password so it can use it to start the lavap process and read from the keyring os.

In order to do that add the "--enter-keyring-password" flag to the lavavisor command line. when the lavavisor bootstrap it will request the password from the user with the following prompt:

INF [Lavavisor] Please enter the keyring password:

2- lavavisor create-service: Creates system files according to given consumer / provider config file and configuration flags.

Arguments: [service-type: "provider" or "consumer"] [service-config-folder]

Required Flags:

• --geolocation
• --from

Optional Flags:

• --create-link
• --log-level
• --directory

Example usage: lavavisor create-service consumer /home/ubuntu/config/consumer-ETH1.yml --geolocation 1 --from user1 --log_level info --keyring-backend test --chain-id lava --node http://127.0.0.1:26657 --create-link

This command generates the service file in '.lavavisor/' directory so that consumer & provider processes can be started in a robust manner. Additionally, it creates a ./logs directory, so that service logs can be easily accessed. Finally, it updates the config.yml file by appending the name of the service created by this command, allowing the created process to be read by the lavavisor start command.

Use the --create-link flag to create a symbolic link to the /etc/systemd/system/ directory; it is highly recommended for ensuring service files are set up properly.

3- lavavisor start: Starts provider/consumer processes given with linked binary and starts lavavisor version monitor.

Optional Flags:

• --auto-download
• --directory

Example usage: lavavisor start --auto-download

This command reads the config.yml file to determine the list of services. Once identified, it starts each service using the linked binary. Concurrently, it also launches the LavaVisor version monitor. This monitor is designed to detect when an upgrade is necessary and will automatically carry out the upgrade process as soon as it's triggered. Here are the operations that lavavisor start performs:

Usage of --auto-download flag is recommended for auto-fetching of upgraded binary (target binary must be exist in GitHub releases).

1. Ensures the .lavavisor directory is present.
2. Reads the config.yml to determine the list of services. Each service is then initiated using the binary linked by the init command.
3. Sets up state tracker parameters and registers its state tracker for protocol version updates.
4. Launches the version monitor as a separate go routine, which activates when the updateTriggered signal is set to true.
5. If an upgrade requirement is detected, the updateTriggered signal is enabled, prompting the version monitor to commence the auto-upgrade process.
6. Once the new binary is either retrieved from .lavavisor/upgrades/<new-version-tag>/ or downloaded from GitHub (note: auto-download must be active), a new link to the binary is established, and the system daemon is restarted.
7. After rebooting the provider and consumer processes, the version monitor resumes its monitoring for potential upgrade events.

Test

1. Run lavavisor init --auto-download → This will setup LavaVisor directory and link the protocol binary
2. Instead of creating service files manually, execute lavavisor create-service command to generate a the service files.
3. Validate .lavavisor/services folder created and with generated service files.
4. Validate config.yml is updated and includes all of the target service names.
5. Execute lavavisor start --auto-start, and you should observe all services running. Additionally, the version monitor will begin validating versions.
6. Now we need to make an upgrade proposal by using /gov module, so that protocol version will change in the consensus and LavaVisor will detect & initiate auto-upgrade.

Here is an example proposal.json file:

{
    "title": "Protocol Version Change",
    "description": "Update version",
    "changes": [
        {
            "subspace": "protocol",
            "key": "Version",
            "value": {
                "provider_target": "0.23.2",
                "consumer_target": "0.23.2",
                "provider_min": "0.22.0",
                "consumer_min": "0.22.0"
            }
        }
    ],
    "deposit": "10000000ulava"
}

Here is the script for sending version update proposal transaction (for Cosmos SDK v0.47.0):

#!/bin/bash
# upgrade script (upgrade_chain.sh)

# function to wait for next block (should be used when proposing on chains with Cosmos SDK 0.47 or higher)
function wait_next_block {
  current=$( lavad q block | jq .block.header.height)
  echo "Waiting for next block $current"
  while true; do
    sleep 0.5
    new=$( lavad q block | jq .block.header.height)
    if [[ $current != $new ]]
    then
      echo "finished waiting for block $new"
        break
    fi
  done
}

# The software upgrade proposal command. This only proposes a software upgrade. To apply the upgrade, you need to vote "yes" (like below).
lavad tx gov submit-legacy-proposal param-change proposal.json \
--gas "auto" \
--from alice \
--keyring-backend "test" \
--gas-prices "0.000000001ulava" \
--gas-adjustment "1.5" \
--yes

wait_next_block

# The vote command. Use vote ID 4 (like here) if you used the init_chain_commands.sh script. If the vote doesn't work because of a bad
# vote ID, use the 'lavad q gov proposals' query to check the latest proposal ID, and put here the latest ID + 1.
lavad tx gov vote 4 yes -y --from alice --gas-adjustment "1.5" --gas "auto" --gas-prices "0.000000001ulava"

(Fix proposal ID 4 according to your state - if you didn’t run ‘init_chain_commands’ you should put 1 there)

1. After the proposal passed, LavaVisor will detect the event and update the binaries. Then, it will reboot the processes with the new established symbolic link: