feat(search): Use an external levenstein automaton implementation

Cargo.lock

@@ -91,15 +91,6 @@ dependencies = [
  "memmap 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "fst-levenshtein"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "fst 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "utf8-ranges 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "fuchsia-zircon"
 version = "0.3.3"
@@ -167,6 +158,14 @@ name = "lazycell"
 version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "levenshtein_automata"
+version = "0.1.0"
+source = "git+https://github.com/tantivy-search/levenshtein-automata.git#ba2b62e3631593c408e2b9b8bb95c430384a331e"
+dependencies = [
+ "fst 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.40"
@@ -307,9 +306,9 @@ dependencies = [
  "bincode 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "fst 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "fst-levenshtein 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "levenshtein_automata 0.1.0 (git+https://github.com/tantivy-search/levenshtein-automata.git)",
  "serde 1.0.45 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.45 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -603,11 +602,6 @@ dependencies = [
  "percent-encoding 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "utf8-ranges"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "winapi"
 version = "0.2.8"
@@ -659,7 +653,6 @@ dependencies = [
 "checksum dtoa 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "09c3753c3db574d215cba4ea76018483895d7bff25a31b49ba45db21c48e50ab"
 "checksum env_logger 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "15abd780e45b3ea4f76b4e9a26ff4843258dd8a3eed2775a0e7368c2e7936c2f"
 "checksum fst 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d94485a00b1827b861dd9d1a2cc9764f9044d4c535514c0760a5a2012ef3399f"
-"checksum fst-levenshtein 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "64f12af1569dd78afbefe476034bbdce0372d18e9dc75b634bde0e7b8bf994c8"
 "checksum fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2e9763c69ebaae630ba35f74888db465e49e259ba1bc0eda7d06f4a067615d82"
 "checksum fuchsia-zircon-sys 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3dcaa9ae7725d12cdb85b3ad99a434db70b468c09ded17e012d86b5c1010f7a7"
 "checksum futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)" = "1a70b146671de62ec8c8ed572219ca5d594d9b06c0b364d5e67b722fc559b48c"
@@ -670,6 +663,7 @@ dependencies = [
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c8f31047daa365f19be14b47c29df4f7c3b581832407daabe6ae77397619237d"
 "checksum lazycell 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a6f08839bc70ef4a3fe1d566d5350f519c5912ea86be0df1740a7d247c7fc0ef"
+"checksum levenshtein_automata 0.1.0 (git+https://github.com/tantivy-search/levenshtein-automata.git)" = "<none>"
 "checksum libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)" = "6fd41f331ac7c5b8ac259b8bf82c75c0fb2e469bbf37d2becbba9a6a2221965b"
 "checksum log 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)" = "e19e8d5c34a3e0e2223db8e060f9e8264aeeb5c5fc64a4ee9965c062211c024b"
 "checksum log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "89f010e843f2b1a31dbd316b3b8d443758bc634bed37aabade59c686d644e0a2"
@@ -716,7 +710,6 @@ dependencies = [
 "checksum unicode-normalization 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "90d662d111b0dbb08a180f2761026cba648c258023c355954a7c00e00e354636"
 "checksum unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"
 "checksum url 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f808aadd8cfec6ef90e4a14eb46f24511824d1ac596b9682703c87056c8678b7"
-"checksum utf8-ranges 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a1ca13c08c41c9c3e04224ed9ff80461d97e121589ff27c753a16cb10830ae0f"
 "checksum winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
 "checksum winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "04e3bd221fcbe8a271359c04f21a76db7d0c6028862d1bb5512d85e1e2eb5bb3"
 "checksum winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"

Cargo.toml

@@ -7,7 +7,7 @@ authors = ["Kerollmops <renault.cle@gmail.com>"]
 bincode = "1.0"
 env_logger = { version = "0.3", default-features = false }
 fst = "0.3"
-fst-levenshtein = "0.2"
+levenshtein_automata = { git = "https://github.com/tantivy-search/levenshtein-automata.git", features = ["fst_automaton"] }
 futures = "0.1"
 lazy_static = "1.0"
 serde = "1.0"

src/bin/raptor.rs

@@ -1,8 +1,8 @@
+#[macro_use] extern crate lazy_static;
 extern crate env_logger;
 extern crate fst;
-extern crate fst_levenshtein;
 extern crate futures;
-#[macro_use]  extern crate lazy_static;
+extern crate levenshtein_automata;
 extern crate raptor;
 extern crate tokio_minihttp;
 extern crate tokio_proto;
@@ -14,8 +14,8 @@ use std::path::Path;
 use std::fs::File;
 use std::io::{Read, BufReader};
 
-use fst_levenshtein::Levenshtein;
 use fst::{IntoStreamer, Streamer};
+use levenshtein_automata::LevenshteinAutomatonBuilder;
 use futures::future;
 use tokio_minihttp::{Request, Response, Http};
 use tokio_proto::TcpServer;
@@ -30,10 +30,17 @@ lazy_static! {
 
         FstMap::from_bytes(map, &values).unwrap()
     };
+
+    static ref LEV_AUT_BLDR_0: LevenshteinAutomatonBuilder = LevenshteinAutomatonBuilder::new(0, false);
+    static ref LEV_AUT_BLDR_1: LevenshteinAutomatonBuilder = LevenshteinAutomatonBuilder::new(1, false);
+    static ref LEV_AUT_BLDR_2: LevenshteinAutomatonBuilder = LevenshteinAutomatonBuilder::new(2, false);
 }
 
 struct MainService {
     map: &'static FstMap<u64>,
+    lev_aut_bldr_0: &'static LevenshteinAutomatonBuilder,
+    lev_aut_bldr_1: &'static LevenshteinAutomatonBuilder,
+    lev_aut_bldr_2: &'static LevenshteinAutomatonBuilder,
 }
 
 fn construct_body<'f, S>(mut stream: S) -> String
@@ -71,14 +78,12 @@ impl Service for MainService {
         if let Some((_, key)) = url.query_pairs().find(|&(ref k, _)| k == "q") {
             let key = key.to_lowercase();
 
-            // TODO prefer using the `tantivy-search/levenshtein-automata` instead
             let lev = if key.len() <= 4 {
-                // TODO prefer using AlwaysMatch with max_len ?
+                self.lev_aut_bldr_0.build_dfa(&key)
-                Levenshtein::new(&key, 0).unwrap()
             } else if key.len() <= 8 {
-                Levenshtein::new(&key, 1).unwrap()
+                self.lev_aut_bldr_1.build_dfa(&key)
             } else {
-                Levenshtein::new(&key, 2).unwrap()
+                self.lev_aut_bldr_2.build_dfa(&key)
             };
 
             let stream = self.map.search(lev).into_stream();
@@ -105,5 +110,10 @@ fn main() {
     drop(env_logger::init());
     let addr = "0.0.0.0:8080".parse().unwrap();
 
-    TcpServer::new(Http, addr).serve(|| Ok(MainService { map: &MAP }))
+    TcpServer::new(Http, addr).serve(|| Ok(MainService {
+        map: &MAP,
+        lev_aut_bldr_0: &LEV_AUT_BLDR_0,
+        lev_aut_bldr_1: &LEV_AUT_BLDR_1,
+        lev_aut_bldr_2: &LEV_AUT_BLDR_2,
+    }))
 }