implements parser

meilisearch-core/Cargo.toml

@@ -20,6 +20,7 @@ heed = "0.7.0"
 indexmap = { version = "1.3.2", features = ["serde-1"] }
 intervaltree = "0.2.5"
 itertools = "0.9.0"
+lazy_static = "1.4.0"
 levenshtein_automata = { version = "0.1.1", features = ["fst_automaton"] }
 log = "0.4.8"
 meilisearch-schema = { path = "../meilisearch-schema", version = "0.9.0" }
@@ -27,12 +28,15 @@ meilisearch-tokenizer = { path = "../meilisearch-tokenizer", version = "0.9.0" }
 meilisearch-types = { path = "../meilisearch-types", version = "0.9.0" }
 once_cell = "1.3.1"
 ordered-float = { version = "1.0.2", features = ["serde"] }
+pest = {git = "https://github.com/MarinPostma/pest.git"} 
+pest_derive = "2.0"
 regex = "1.3.6"
 sdset = "0.4.0"
 serde = { version = "1.0.105", features = ["derive"] }
 serde_json = "1.0.50"
 siphasher = "0.3.2"
 slice-group-by = "0.2.6"
+unicase = "2.6.0"
 zerocopy = "0.3.0"
 
 [dev-dependencies]

meilisearch-core/src/filters/parser/grammar.pest

@@ -0,0 +1,28 @@
+key = _{quoted | word}
+value = _{quoted | word}
+quoted = _{ (PUSH("'") | PUSH("\"")) ~ string ~ POP  }
+string = {char*}
+word = ${(LETTER | NUMBER | "_" | "-")+}
+
+char =  _{ !(PEEK | "\\") ~ ANY
+    | "\\" ~ (PEEK | "\\" | "/" | "b" | "f" | "n" | "r" | "t")
+    | "\\" ~ ("u" ~ ASCII_HEX_DIGIT{4})}
+
+condition = _{eq | greater | less | geq | leq | neq}
+geq = {key ~ ">=" ~ value}
+leq = {key ~ "<=" ~ value}
+neq = {key ~ "!=" ~ value}
+eq = {key ~ "=" ~ value}
+greater = {key ~ ">" ~ value}
+less = {key ~ "<" ~ value}
+
+prgm = {SOI ~ expr ~ EOI}
+expr = _{ ( term ~ (operation ~ term)* ) }
+term = _{ ("(" ~ expr ~ ")") | condition | not }
+operation = _{ and | or }
+	and = {"AND"}
+	or = {"OR"}
+
+not = {"NOT" ~ term}
+
+WHITESPACE = _{ " " }

meilisearch-core/src/filters/parser/mod.rs

@@ -0,0 +1,14 @@
+use lazy_static::lazy_static;
+use pest::prec_climber::{Operator, Assoc, PrecClimber};
+
+lazy_static! {
+    pub static ref PREC_CLIMBER: PrecClimber<Rule> = {
+        use Assoc::*;
+        use Rule::*;
+        pest::prec_climber::PrecClimber::new(vec![Operator::new(or, Left), Operator::new(and, Left)])
+    };
+}
+
+#[derive(Parser)]
+#[grammar = "filters/parser/grammar.pest"]
+pub struct FilterParser;