Fetch all variables into a map before rolling dice.

Goes from about 30 seconds to do 1 million variable resolutions down
to 18 seconds.
This commit is contained in:
projectmoon 2020-10-18 00:35:09 +00:00 committed by ProjectMoon
parent d5aae3ebb1
commit ce82e6ddad
3 changed files with 70 additions and 21 deletions

3
.gitignore vendored
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@ -6,3 +6,6 @@ cache
*.tar *.tar
*.tar.gz *.tar.gz
test-db/ test-db/
# We store a disabled async test in this file
bigboy

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@ -122,12 +122,24 @@ pub struct DicePool {
async fn calculate_dice_amount<'a>(pool: &'a DicePoolWithContext<'a>) -> Result<i32, BotError> { async fn calculate_dice_amount<'a>(pool: &'a DicePoolWithContext<'a>) -> Result<i32, BotError> {
let stream = stream::iter(&pool.0.amounts); let stream = stream::iter(&pool.0.amounts);
let variables = pool
.1
.db
.get_user_variables(&pool.1.room_id, &pool.1.username)
.await?;
let variables = &variables;
use DiceRollingError::VariableNotFound;
let dice_amount: Result<i32, BotError> = stream let dice_amount: Result<i32, BotError> = stream
.then(|amount| async move { .then(|amount| async move {
match &amount.element { match &amount.element {
Element::Number(num_dice) => Ok(*num_dice * amount.operator.mult()), Element::Number(num_dice) => Ok(*num_dice * amount.operator.mult()),
Element::Variable(variable) => handle_variable(&pool.1, &variable).await, Element::Variable(variable) => variables
.get(variable)
.ok_or(VariableNotFound(variable.clone().to_string()))
.map(|i| *i)
.map_err(|e| e.into()),
} }
}) })
.try_fold(0, |total, num_dice| async move { Ok(total + num_dice) }) .try_fold(0, |total, num_dice| async move { Ok(total + num_dice) })
@ -352,16 +364,6 @@ fn roll_die<R: DieRoller>(roller: &mut R, pool: &DicePool) -> Vec<i32> {
results results
} }
async fn handle_variable(ctx: &Context, variable: &str) -> Result<i32, BotError> {
ctx.db
.get_user_variable(&ctx.room_id, &ctx.username, variable)
.await
.map_err(|e| match e {
KeyDoesNotExist(_) => DiceRollingError::VariableNotFound(variable.to_owned()).into(),
_ => e.into(),
})
}
fn roll_dice<'a, R: DieRoller>(pool: &DicePool, num_dice: i32, roller: &mut R) -> Vec<i32> { fn roll_dice<'a, R: DieRoller>(pool: &DicePool, num_dice: i32, roller: &mut R) -> Vec<i32> {
(0..num_dice) (0..num_dice)
.flat_map(|_| roll_die(roller, &pool)) .flat_map(|_| roll_die(roller, &pool))

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@ -1,5 +1,6 @@
use byteorder::LittleEndian; use byteorder::LittleEndian;
use sled::{Db, IVec}; use sled::{Db, IVec};
use std::collections::HashMap;
use thiserror::Error; use thiserror::Error;
use zerocopy::byteorder::I32; use zerocopy::byteorder::I32;
use zerocopy::{AsBytes, LayoutVerified}; use zerocopy::{AsBytes, LayoutVerified};
@ -14,13 +15,18 @@ pub struct Database {
db: Db, db: Db,
} }
//TODO better combining of key and value in certain errors (namely
//I32SchemaViolation).
#[derive(Error, Debug)] #[derive(Error, Debug)]
pub enum DataError { pub enum DataError {
#[error("value does not exist for key: {0}")] #[error("value does not exist for key: {0}")]
KeyDoesNotExist(String), KeyDoesNotExist(String),
#[error("key violates expected schema: {0}")] #[error("expected i32, but i32 schema was violated")]
SchemaViolation(String), I32SchemaViolation,
#[error("expected string, but utf8 schema was violated: {0}")]
Utf8chemaViolation(#[from] std::str::Utf8Error),
#[error("internal database error: {0}")] #[error("internal database error: {0}")]
InternalError(#[from] sled::Error), InternalError(#[from] sled::Error),
@ -34,11 +40,56 @@ fn to_key(room_id: &str, username: &str, variable_name: &str) -> Vec<u8> {
key key
} }
fn to_prefix(room_id: &str, username: &str) -> Vec<u8> {
let mut prefix = vec![];
prefix.extend_from_slice(room_id.as_bytes());
prefix.extend_from_slice(username.as_bytes());
prefix
}
fn convert(raw_value: &[u8]) -> Result<i32, DataError> {
let layout = LittleEndianI32Layout::new_unaligned(raw_value.as_ref());
if let Some(layout) = layout {
let value: I32<LittleEndian> = *layout;
Ok(value.get())
} else {
Err(DataError::I32SchemaViolation)
}
}
impl Database { impl Database {
pub fn new(db: &Db) -> Database { pub fn new(db: &Db) -> Database {
Database { db: db.clone() } Database { db: db.clone() }
} }
pub async fn get_user_variables(
&self,
room_id: &str,
username: &str,
) -> Result<HashMap<String, i32>, DataError> {
let prefix = to_prefix(&room_id, &username);
let prefix_len: usize = prefix.len();
let variables: Result<Vec<_>, DataError> = self
.db
.scan_prefix(prefix)
.map(|entry| match entry {
Ok((key, raw_value)) => {
//Strips room and username from key, leaving
//behind name.
let variable_name = std::str::from_utf8(&key[prefix_len..])?;
Ok((variable_name.to_owned(), convert(&raw_value)?))
}
Err(e) => Err(e.into()),
})
.collect();
//Convert to hash map. Can we do this in the first mapping
//step instead?
variables.map(|entries| entries.into_iter().collect())
}
pub async fn get_user_variable( pub async fn get_user_variable(
&self, &self,
room_id: &str, room_id: &str,
@ -48,14 +99,7 @@ impl Database {
let key = to_key(room_id, username, variable_name); let key = to_key(room_id, username, variable_name);
if let Some(raw_value) = self.db.get(&key)? { if let Some(raw_value) = self.db.get(&key)? {
let layout = LittleEndianI32Layout::new_unaligned(raw_value.as_ref()); convert(&raw_value)
if let Some(layout) = layout {
let value: I32<LittleEndian> = *layout;
Ok(value.get())
} else {
Err(DataError::SchemaViolation(String::from_utf8(key).unwrap()))
}
} else { } else {
Err(DataError::KeyDoesNotExist(String::from_utf8(key).unwrap())) Err(DataError::KeyDoesNotExist(String::from_utf8(key).unwrap()))
} }