Use string cache and update README

src/compressor.rs

@@ -16,6 +16,7 @@
 
 
 use rust_matrix_lib::state_map::StateMap;
+use string_cache::DefaultAtom as Atom;
 
 use std::collections::BTreeMap;
 
@@ -159,7 +160,7 @@ impl<'a> Compressor<'a> {
     /// group that can be used as a base for a delta.
     ///
     /// Returns the state map and the actual base state group (if any) used.
-    fn get_delta(&mut self, prev_sg: Option<i64>, sg: i64) -> (StateMap<String>, Option<i64>) {
+    fn get_delta(&mut self, prev_sg: Option<i64>, sg: i64) -> (StateMap<Atom>, Option<i64>) {
         let state_map = collapse_state_maps(&self.original_state_map, sg);
 
         let mut prev_sg = if let Some(prev_sg) = prev_sg {

src/database.rs

@@ -84,7 +84,7 @@ fn get_initial_data_from_db(conn: &Connection, room_id: &str) -> BTreeMap<i64, S
         if let Some(etype) = etype {
             entry
                 .state_map
-                .insert(&etype, &row.get::<_, String>(3), row.get(4));
+                .insert(&etype, &row.get::<_, String>(3), row.get::<_, String>(4).into());
         }
 
         pb.inc(1);

src/main.rs

@@ -9,6 +9,7 @@ extern crate indicatif;
 extern crate postgres;
 extern crate rayon;
 extern crate rust_matrix_lib;
+extern crate string_cache;
 
 mod compressor;
 mod database;
@@ -18,6 +19,7 @@ use compressor::Compressor;
 use clap::{App, Arg};
 use rayon::prelude::*;
 use rust_matrix_lib::state_map::StateMap;
+use string_cache::DefaultAtom as Atom;
 
 use std::collections::BTreeMap;
 use std::fs::File;
@@ -29,14 +31,14 @@ use std::str::FromStr;
 #[derive(Default, Debug, Clone, PartialEq, Eq)]
 pub struct StateGroupEntry {
     prev_state_group: Option<i64>,
-    state_map: StateMap<String>,
+    state_map: StateMap<Atom>,
 }
 
 /// Gets the full state for a given group from the map (of deltas)
 pub fn collapse_state_maps(
     map: &BTreeMap<i64, StateGroupEntry>,
     state_group: i64,
-) -> StateMap<String> {
+) -> StateMap<Atom> {
     let mut entry = &map[&state_group];
     let mut state_map = StateMap::new();