Logging steps in fca00c:Asteroids with a proxy contract
Paul
Posted on March 30, 2023
In the previous post we discussed how to implement a proxy contract for the game_engine to log solution-steps in fca00c:Asteroids. Now let's add a bit of flesh to it.
Recap
We have learned that in soroban
- any client generated from a
WASMcan be used to interact with any other contract as long as the functions exist on both - when building a contract without
debug-assertionsthe proxy still can be used for logging- logging-capabilities are a bit limited due to the absence of
std - the code can be found on github
- logging-capabilities are a bit limited due to the absence of
Adding actual logging to the existing logging_engine
Let's continue where we left off: https://github.com/hanseartic/fca00c-asteroids/tree/proxy_engine.
First thing we'd need to do is to record all the steps that are invoked on the game_engine. Ideally we'd only record actions that change the state of the game and skip the read-only operations.
For that we need to persist the actions:
fn log_action(env: &Env, action: &ActionItem) {
let mut actions = Self::actions(env.clone());
actions.push_back(*action);
env.storage().set(&ACTIONS, &actions);
}
and call this function in every function that changes the game's state, e.g. like:
pub fn p_turn(env: Env, direction: game_engine::Direction) -> Result<(), game_engine::Error> {
- Ok(Self::get_engine(&env).p_turn(&direction))
+ if let Err(Ok(e)) = Self::get_engine(&env).try_p_turn(&direction) {
+ return Err(e);
+ }
+ Self::log_action(&env, &ActionItem(Action::Turn, direction as u32));
+ Ok(())
}
Lets add this to all functions (see complete diff).
Printing the recorded actions in test
To see the recorded actions we need to print them in the test-case.
--- a/contracts/solution/src/test.rs
+++ b/contracts/solution/src/test.rs
@@ -40,9 +40,8 @@ fn fca00c_fast() {
let env = Env::default();
let proxy_engine_id = env.register_contract_wasm(None, logging_contract::WASM);
let engine_id = env.register_contract_wasm(None, GameEngineWASM);
- let engine = GameEngine::new(&env, &proxy_engine_id);
-
- logging_contract::Client::new(&env, &proxy_engine_id).wrap(&engine_id);
+ let engine = logging_contract::Client::new(&env, &proxy_engine_id);
+ engine.wrap(&engine_id);
// DON'T CHANGE THE FOLLOWING INIT() PARAMETERS
// Once you've submitted your contract on the FCA00C site, we will invoke
Stage this hunk [y,n,q,a,d,j,J,g,/,e,?]? y
@@ -79,6 +78,12 @@ fn fca00c_fast() {
let logs = env.logger().all();
println!("{}", logs.join("\n"));
+ for action in engine.actions() {
+ if let Ok(a) = action {
+ println!("{:?}", a);
+ }
+ }
+
let points = engine.p_points();
println!("Points: {}", points);
š as we might be adding more function to the log-contract it makes sense to use the logging_engine::Client for all invocations. The other way was just there to show the client does not actually matter as long as it implements a function present in the contract
and run the test again
āÆ make test
cargo test fca00c_fast -- --nocapture
Compiling soroban-asteroids-solution v0.0.0 (/home/paul/Code/fca00c - logging proxy/contracts/solution)
Finished test [unoptimized + debuginfo] target(s) in 4.94s
Running unittests src/lib.rs (target/debug/deps/soroban_asteroids_solution-5b0a3423b755223b)
running 1 test
invoker account is not configured
invoker account is not configured
šļø logger engine taking notes
ActionItem(Shoot, 1)
Points: 1
test test::fca00c_fast ... ok
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 1 filtered out; finished in 0.56s
āÆ
š notice ActionItem(Shoot, 1) in the logs - that's us shooting and hitting one asteroid
Improving the output
We can rely on the debugging capabilities of println! macro or implement a slightly more fine-grained logging directly in the logging_engine. Let's for example add up all consecutive p_move calls and only record the last of multiple consecutive p_turn commands.
--- a/contracts/logging_engine/src/engine.rs
+++ b/contracts/logging_engine/src/engine.rs
@@ -30,7 +30,26 @@ impl LoggingEngine {
}
fn log_action(env: &Env, action: &ActionItem) {
let mut actions = Self::actions(env.clone());
- actions.push_back(*action);
+ let add_action: ActionItem;
+
+ if let Some(Ok(last_action_item)) = actions.last() {
+ match last_action_item {
+ ActionItem(Action::Turn, _) if action.0 == Action::Turn => {
+ actions.pop_back();
+ add_action = action.clone();
+ }
+ ActionItem(Action::Move, _) if action.0 == Action::Move => {
+ actions.pop_back();
+ add_action = ActionItem(last_action_item.0, last_action_item.1 + (action.1 as u32));
+
+ }
+ _ => add_action = *action,
+ }
+ } else {
+ add_action = *action;
+ }
+
+ actions.push_back(add_action);
env.storage().set(&ACTIONS, &actions);
}
š don't forget to compile!
Now let's add some more calls to the game_engine in our solution:
--- a/contracts/solution/src/lib.rs
+++ b/contracts/solution/src/lib.rs
@@ -1,6 +1,6 @@
#![no_std]
-use engine::Client as GameEngine;
+use engine::{Client as GameEngine, Direction};
use soroban_sdk::{contractimpl, BytesN, Env};
pub struct Solution;
@@ -19,6 +19,12 @@ impl Solution {
// YOUR CODE START
engine.p_shoot();
+ engine.p_move(&None);
+ engine.p_move(&Some(2));
+ engine.p_turn(&Direction::UpLeft);
+ engine.p_turn(&Direction::Left);
+ engine.p_move(&Some(1));
+ engine.p_turn(&Direction::Down);
// YOUR CODE END
}
}
we would expect consecutive moves to be summed up as well as only the last of multiple consecutive turns to be logged
Let's take a look at the test-results:
šļø logger engine taking notes
ActionItem(Shoot, 1)
ActionItem(Move, 3)
ActionItem(Turn, 6)
ActionItem(Move, 1)
ActionItem(Turn, 4)
Points: 1
Looking good!
Check the diff of what we did here.
Customize the logs
Let's add a bit of color to the logs, shall we?
So let's have two options, one to be easily parseable (if you want to play back to steps) and one to be playful and nice to the human eye.
--- a/contracts/logging_engine/src/types.rs
+++ b/contracts/logging_engine/src/types.rs
@@ -1,4 +1,4 @@
-use soroban_sdk::{contracterror, contracttype};
+use soroban_sdk::{contracterror, contracttype, Env};
#[contracterror]
#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd)]
@@ -21,3 +21,15 @@ pub enum Action {
#[contracttype]
#[derive(Copy, Clone)]
pub struct ActionItem(pub Action, pub u32);
+
+#[contracttype]
+#[derive(Copy, Clone, Debug, PartialEq)]
+pub enum LogLevel {
+ Quiet,
+ Human,
+ Machine,
+}
+
+pub trait LogFormat {
+ fn log_format(&self, env: &Env, level: &LogLevel);
+}
and define a trait how we expect logs to be called.
Now let's implement this
--- a/contracts/logging_engine/src/engine.rs
+++ b/contracts/logging_engine/src/engine.rs
@@ -1,5 +1,5 @@
use soroban_sdk::{contractimpl, log, panic_with_error, vec, BytesN, Env, Map, Vec};
-use crate::types::{Action, ActionItem, ProxyError};
+use crate::types::{Action, ActionItem, LogFormat, LogLevel, ProxyError};
mod game_engine {
soroban_sdk::contractimport!(file = "../game_engine.wasm");
@@ -53,6 +53,42 @@ impl LoggingEngine {
env.storage().set(&ACTIONS, &actions);
}
+ pub fn get_logs(env: Env, level: LogLevel) {
+ log!(&env, "\n");
+ if LogLevel::Quiet == level {
+ log!(&env, "š¤· `LogLevel::Quiet` won't output any logs.");
+ return;
+ }
+ log!(&env, "š¼ here are the recorded steps:\n");
+
+ log!(&env, "\n==< MEANING >==\n");
+ match level {
+ LogLevel::Human => {
+ log!(&env, "š§°: upgrade");
+ log!(&env, "š¶: move");
+ log!(&env, "āā: turning");
+ log!(&env, "š«š[š[š]]: hit(s)");
+ log!(&env, "ā½: harvest");
+ }
+ LogLevel::Machine => {
+ log!(&env, "0: upgrade");
+ log!(&env, "1..3: hit");
+ log!(&env, "4: harvest");
+ log!(&env, "8..15: turning");
+ log!(&env, "16..: move");
+ }
+ _ => (),
+ };
+
+ log!(&env, "\n===< STEPS >===\n");
+ for a_i in Self::actions(env.clone()) {
+ if let Ok(a) = a_i {
+ a.log_format(&env, &level);
+ }
+ }
+ log!(&env, "\n===============\n");
+ }
+
/// wrapping interface implemention
pub fn init(
env: Env,
@@ -134,3 +170,52 @@ impl LoggingEngine {
Self::get_engine(&env).get_map()
}
}
+
+impl LogFormat for ActionItem {
+ fn log_format(&self, env: &Env, level: &LogLevel) {
+ match &self.0 {
+ Action::Harvest => match level {
+ LogLevel::Human => log!(&env, "ā½"),
+ LogLevel::Machine => log!(&env, "4"),
+ _ => (),
+ },
+ Action::Upgrade => match level {
+ LogLevel::Human => log!(&env, "š§°"),
+ LogLevel::Machine => log!(&env, "0"),
+ _ => (),
+ },
+ Action::Shoot => match level {
+ LogLevel::Human => {
+ match self.1 {
+ 3 => log!(&env, "š«ššš"),
+ 2 => log!(&env, "š«šš"),
+ 1 => log!(&env, "š«š"),
+ _ => log!(&env, "š«"),
+ };
+ }
+ LogLevel::Machine => log!(&env, "{}", self.1 as u32),
+ _ => (),
+ },
+ Action::Move => match level {
+ LogLevel::Human => log!(&env, "š¶ {}", self.1),
+ LogLevel::Machine => log!(&env, "{}", self.1 as u32 + 15),
+ _ => (),
+ },
+ Action::Turn => match level {
+ LogLevel::Human => match self.1 {
+ 0 => log!(&env, "ā§"),
+ 1 => log!(&env, "ā"),
+ 2 => log!(&env, "ā"),
+ 3 => log!(&env, "ā"),
+ 4 => log!(&env, "ā©"),
+ 5 => log!(&env, "ā"),
+ 6 => log!(&env, "ā¦"),
+ 7 => log!(&env, "ā"),
+ _ => (),
+ },
+ LogLevel::Machine => log!(&env, "{}", (self.1 as u32) + 8),
+ _ => (),
+ },
+ };
+ }
+}
We've just added a way to present the logs in different variations. Let's check back with the tests.
But first we of course need to a) compile the logging_engine and b) add a call to the newly added log-function:
--- a/contracts/solution/src/test.rs
+++ b/contracts/solution/src/test.rs
@@ -75,15 +75,13 @@ fn fca00c_fast() {
solution.solve(&proxy_engine_id);
+ engine.get_logs(&logging_contract::LogLevel::Human);
+ engine.get_logs(&logging_contract::LogLevel::Machine);
+ engine.get_logs(&logging_contract::LogLevel::Quiet);
+
let logs = env.logger().all();
println!("{}", logs.join("\n"));
- for action in engine.actions() {
- if let Ok(a) = action {
- println!("{:?}", a);
- }
- }
-
let points = engine.p_points();
println!("Points: {}", points);
Here we go:
šļø logger engine taking notes
š¼ here are the recorded steps:
==< MEANING >==
š§°: upgrade
š¶: move
āā: turning
š«š[š[š]]: hit(s)
ā½: harvest
===< STEPS >===
š«š
š¶ U32(3)
ā¦
š¶ U32(1)
ā©
===============
š¼ here are the recorded steps:
==< MEANING >==
0: upgrade
1..3: hit
4: harvest
8..15: turning
16..: move
===< STEPS >===
U32(1)
U32(18)
U32(14)
U32(16)
U32(12)
===============
š¤· `LogLevel::Quiet` won't output any logs.
Points: 1
š Congratulations! We've added nice looking, customizable logging to the challenge without bloating our solution!
Now you just need to solve the actual fca00c:Asteroids challenge - the all-time leaderboard is still open for submissions!!!
Drawbacks
- As the
u32type is always rendered asU32(<VALUE>)numbers can't nicely be logged from soroban (yet). - To proxy another contract we'd need to implement the complete interface again. There is no generic proxying solution in soroban.
Posted on March 30, 2023
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