10 releases (4 breaking)
0.19.0 | Apr 7, 2021 |
---|---|
0.18.1 | Feb 11, 2021 |
0.18.0 | Jan 29, 2021 |
0.17.0 | Dec 17, 2020 |
0.15.0 | Jul 20, 2020 |
#28 in #bft
2MB
32K
SLoC
See the repo root for build status, license, rust version, etc.
Light-Node
The Tendermint light-node wraps the light-client crate into a command-line interface tool. It can be used as a standalone light client daemon and exposes a JSON-RPC endpoint from which you can query the current state of the light node.
Getting Started
Prerequisites
This short tutorial assumes that you are familiar with how to run a Tendermint fullnode on your machine. To learn how to do this, you can consult the quick start section of the tendermint documentation.
This tutorial further assumes you have git
and the latest stable rust tool-chain installed (see https://rustup.rs/).
Additionally, the jq
tool will make your life easier when dealing with JSON output.
Cloning the repository
To run the light node from source you have to clone this repository first:
$ git clone https://github.com/informalsystems/tendermint-rs.git
Then navigate to the light node crate:
$ cd tendermint-rs/light-node
Configuration
You can configure all aspects of light node via a configuration file. An example configuration can be found under light_node.toml.example.
If you are running a Tendermint fullnode on your machine, you can simply copy and use it to get started:
$ cp light_node.toml.example light_node.toml
Please, take a look into the config file and edit it according to your needs. The provided example configuration file comes with a lot of explanatory comments which hopefully provide enough guidance to configure your light node.
Subjective initialization
Assuming that you are running a Tendermint fullnode that exposes an RPC endpoint on your loopback interface, you can intialize the light-node subjectively following th following steps:
First, you have to obtain a header hash and height you want to trust (subjectively). For our purposes you can obtain one via querying the Tendermint fullnode you are running. Here we are obtaining the header hash of height 2:
$ curl -X GET "http://localhost:26657/block?height=2" -H "accept: application/json" | jq .result.block_id.hash 1515:15:26
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 2155 0 2155 0 0 161k 0 --:--:-- --:--:-- --:--:-- 161k
"76F85BEF1133114482FC8F78C5E78D2B1C1875DD8422A0394B175DD694A7FBA1"
You can now use this header hash to subjectively initialize your light node via:
$ cargo run -- initialize 2 76F85BEF1133114482FC8F78C5E78D2B1C1875DD8422A0394B175DD694A7FBA1
Note that calling cargo run
for the first time might take a while as this command will also compile the light node and all its dependencies.
Running the light node daemon
Now you can start your light node by simply running:
$ cargo run -- start
If everything worked the output will look sth like:
cargo run -- start 17:56:31
Finished dev [unoptimized + debuginfo] target(s) in 0.42s
Running `/redacted/tendermint-rs/target/debug/light_node start`
[info] synced to block 20041
[info] synced to block 20042
[info] synced to block 20044
[info] synced to block 20046
[info] synced to block 20048
[info] synced to block 20049
[info] synced to block 20051
[info] synced to block 20053
[info] synced to block 20054
[...]
You can stop the light node by pressing Ctrl+c.
Help
You will notice that some config parameters can be overwritten via command line arguments.
To get a full overview and commandline parameters and available sub-commands, run:
$ cargo run -- help
Or on a specific sub-command, e.g.:
$ cargo run -- help start
JSON-RPC Endpoint(s)
When you have a light-node running you can query its current state via:
$ curl localhost:8888 -X POST -H 'Content-Type: application/json' \
-d '{"jsonrpc": "2.0", "method": "state", "id": 1}' | jq
Or you can query a shorter summary via the /status
endpoint:
$ curl localhost:8888 -X POST -H 'Content-Type: application/json'\ 15:58:52
-d '{"jsonrpc": "2.0", "method": "status", "id": 1}' | jq
Click here to see an example for expected output for the status endpoint:
$ curl localhost:8888 -X POST -H 'Content-Type: application/json' \
-d '{"jsonrpc": "2.0", "method": "status", "id": 1}' | jq
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 364 100 317 100 47 1843 273 --:--:-- --:--:-- --:--:-- 2104
{
"jsonrpc": "2.0",
"result": {
"block_hash": "ED745723430944215F65ED78AD7DF9ED0AA8A2A3B465BF421E0BAF66AA55AA08",
"connected_nodes": [
"BADFADAD0BEFEEDC0C0ADEADBEEFC0FFEEFACADE",
"CEFEEDBADFADAD0C0CEEFACADE0ADEADBEEFC0FF"
],
"height": 3850,
"valset_hash": "74F2AC2B6622504D08DD2509E28CE731985CFE4D133C9DB0CB85763EDCA95AA3"
},
"id": 1
}
Click here to see an example for expected output for the state endpoint:
Command:
$ curl localhost:8888 -X POST -H 'Content-Type: application/json' \
-d '{"jsonrpc": "2.0", "method": "state", "id": 1}' | jq
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 1902 100 1856 100 46 164k 4181 --:--:-- --:--:-- --:--:-- 168k
Example output:
{
"jsonrpc": "2.0",
"result": {
"next_validator_set": {
"validators": [
{
"address": "AD358F20C8CE80889E0F0248FDDC454595D632AE",
"proposer_priority": "0",
"pub_key": {
"type": "tendermint/PubKeyEd25519",
"value": "uo9rbgR5J0kuED0C529bTa6mcHZ4uXDjJRdg1k8proY="
},
"voting_power": "10"
}
]
},
"provider": "BADFADAD0BEFEEDC0C0ADEADBEEFC0FFEEFACADE",
"signed_header": {
"commit": {
"block_id": {
"hash": "76F85BEF1133114482FC8F78C5E78D2B1C1875DD8422A0394B175DD694A7FBA1",
"parts": {
"hash": "568F279E3F59FBE3CABEACE7A3C028C15CA6A902F9D77DDEBA3BFCB9514E2881",
"total": "1"
}
},
"height": "2",
"round": "0",
"signatures": [
{
"block_id_flag": 2,
"signature": "sN3e6bzKLeIFNRptQ4SytBDLZJA53e92D6FWTll5Lq8Wdg4fVzxya6qx3SHFU82ukuj8jKmBMkwTTJsb8xThCQ==",
"timestamp": "2020-07-10T12:39:06.977628900Z",
"validator_address": "AD358F20C8CE80889E0F0248FDDC454595D632AE"
}
]
},
"header": {
"app_hash": "0000000000000000",
"chain_id": "dockerchain",
"consensus_hash": "048091BC7DDC283F77BFBF91D73C44DA58C3DF8A9CBC867405D8B7F3DAADA22F",
"data_hash": null,
"evidence_hash": null,
"height": "2",
"last_block_id": {
"hash": "F008EACA817CF6A3918CF7A6FD44F1F2464BB24D25A7EDB45A03E8783E9AB438",
"parts": {
"hash": "BF5130E879A02AC4BB83E392732ED4A37BE2F01304A615467EE7960858774E57",
"total": "1"
}
},
"last_commit_hash": "474496740A2EAA967EED02B239DA302BAF696AE36AEA78F7FEFCE4A77CCA5B33",
"last_results_hash": null,
"next_validators_hash": "74F2AC2B6622504D08DD2509E28CE731985CFE4D133C9DB0CB85763EDCA95AA3",
"proposer_address": "AD358F20C8CE80889E0F0248FDDC454595D632AE",
"time": "2020-07-10T12:39:05.977628900Z",
"validators_hash": "74F2AC2B6622504D08DD2509E28CE731985CFE4D133C9DB0CB85763EDCA95AA3",
"version": {
"app": "1",
"block": "10"
}
}
},
"validator_set": {
"validators": [
{
"address": "AD358F20C8CE80889E0F0248FDDC454595D632AE",
"proposer_priority": "0",
"pub_key": {
"type": "tendermint/PubKeyEd25519",
"value": "uo9rbgR5J0kuED0C529bTa6mcHZ4uXDjJRdg1k8proY="
},
"voting_power": "10"
}
]
}
},
"id": 1
}
Dependencies
~29–43MB
~808K SLoC