Add query module for searching

Cargo.lock

@@ -10,11 +10,6 @@ name = "autocfg"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "byteorder"
-version = "1.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "cfg-if"
 version = "0.1.9"
@@ -28,7 +23,7 @@ dependencies = [
  "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.97 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.98 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -46,7 +41,8 @@ version = "0.1.0"
 dependencies = [
  "chrono 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.97 (registry+https://github.com/rust-lang/crates.io-index)",
+ "nom 5.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.98 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "zip 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -61,6 +57,18 @@ name = "itoa"
 version = "0.4.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "lexical-core"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "stackvector 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "static_assertions 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.60"
@@ -68,16 +76,30 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libflate"
-version = "0.1.25"
+version = "0.1.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "adler32 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc32fast 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rle-decode-fast 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "take_mut 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "memchr"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "nom"
+version = "5.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "lexical-core 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "num-integer"
 version = "0.1.41"
@@ -126,27 +148,48 @@ name = "rle-decode-fast"
 version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "rustc_version"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "serde"
+name = "semver"
-version = "1.0.97"
+version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde_derive 1.0.97 (registry+https://github.com/rust-lang/crates.io-index)",
+ "semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "semver-parser"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "serde"
+version = "1.0.98"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "serde_derive 1.0.98 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.97"
+version = "1.0.98"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -156,12 +199,26 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "itoa 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.97 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.98 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "stackvector"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unreachable 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "static_assertions"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "syn"
-version = "0.15.40"
+version = "0.15.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -189,6 +246,24 @@ name = "unicode-xid"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "unreachable"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "version_check"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "void"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "winapi"
 version = "0.3.7"
@@ -214,21 +289,23 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "crc32fast 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libflate 0.1.25 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libflate 0.1.26 (registry+https://github.com/rust-lang/crates.io-index)",
  "podio 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
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+"checksum memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "88579771288728879b57485cc7d6b07d648c9f0141eb955f8ab7f9d45394468e"
+"checksum nom 5.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e9761d859320e381010a4f7f8ed425f2c924de33ad121ace447367c713ad561b"
 "checksum num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)" = "b85e541ef8255f6cf42bbfe4ef361305c6c135d10919ecc26126c4e5ae94bc09"
 "checksum num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "6ba9a427cfca2be13aa6f6403b0b7e7368fe982bfa16fccc450ce74c46cd9b32"
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@@ -236,14 +313,22 @@ dependencies = [
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Cargo.toml

@@ -14,6 +14,9 @@ features = ["serde"]
 [dependencies.hex]
 version = "*"
 
+[dependencies.nom]
+version = "5"
+
 [dependencies.serde]
 version = "*"
 features = ["derive"]

src/main.rs

@@ -2,6 +2,7 @@
 
 pub mod archive;
 pub mod error;
+pub mod query;
 
 use std::env::args;
 use std::time::Instant;

src/query/mod.rs

@@ -0,0 +1,6 @@
+//! Query module.
+
+mod optimizer;
+mod parser;
+
+pub use self::parser::parse;

src/query/optimizer.rs

@@ -0,0 +1,87 @@
+//! Query optimizer.
+
+use std::str::FromStr;
+
+use chrono::prelude::*;
+
+use super::parser::{Operator, Source};
+use crate::archive::Story;
+use crate::error::{Error, Result};
+
+use Operator::*;
+use Source::*;
+
+type Filter = Box<dyn Fn(&Story) -> bool + Sync>;
+
+type IntFn = Box<dyn Fn(&Story) -> i64 + Sync>;
+type StrFn = Box<dyn Fn(&Story) -> &str + Sync>;
+type DtuFn = Box<dyn Fn(&Story) -> &Option<DateTime<Utc>> + Sync>;
+
+macro_rules! ok {
+    ($func:expr) => {
+        Ok(Box::new($func))
+    };
+}
+
+pub fn optimize(src: Source, op: Operator, value: &str) -> Result<Filter> {
+    match src {
+        StrFn(f) => strfn(f, op, value),
+        IntFn(f) => intfn(f, op, value),
+        DtuFn(f) => dtufn(f, op, value),
+    }
+}
+
+fn strfn(f: StrFn, op: Operator, value: &str) -> Result<Filter> {
+    let value: String = match op {
+        Fuzzy => value.to_lowercase(),
+        _ => value.to_owned(),
+    };
+
+    match op {
+        Exact => ok!(move |s| f(s) == &value),
+        Fuzzy => ok!(move |s| f(s).to_lowercase().contains(&value)),
+        _ => Err(Error::query("Invalid operation for text type")),
+    }
+}
+
+fn intfn(f: IntFn, op: Operator, value: &str) -> Result<Filter> {
+    let value: i64 = value.parse().map_err(|e| match e {
+        _ => Error::query("Invalid value for number type"),
+    })?;
+
+    match op {
+        Exact => ok!(move |s| f(s) == value),
+        Fuzzy => ok!(move |s| f(s) == value),
+        LessThan => ok!(move |s| f(s) < value),
+        MoreThan => ok!(move |s| f(s) > value),
+    }
+}
+
+fn dtufn(f: DtuFn, op: Operator, value: &str) -> Result<Filter> {
+    let parsed = DateTime::from_str(value);
+
+    let value: DateTime<Utc> = parsed.map_err(|e| match e {
+        _ => Error::query("Invalid value for date type"),
+    })?;
+
+    let date = value.date();
+
+    match op {
+        Exact => ok!(move |s| match f(s) {
+            Some(dt) => dt == &value,
+            None => false,
+        }),
+        Fuzzy => ok!(move |s| match f(s) {
+            Some(dt) => dt.date() == date,
+            None => false,
+        }),
+        LessThan => ok!(move |s| match f(s) {
+            Some(dt) => dt < &value,
+            None => false,
+        }),
+        MoreThan => ok!(move |s| match f(s) {
+            Some(dt) => dt > &value,
+            None => false,
+        }),
+    }
+}

src/query/parser.rs

@@ -0,0 +1,215 @@
+//! Query parser.
+
+use chrono::prelude::*;
+
+use nom::character::complete::*;
+use nom::error::ErrorKind as NomErrorKind;
+use nom::sequence::*;
+use nom::*;
+
+use super::optimizer::optimize;
+use crate::archive::Story;
+use crate::error::*;
+
+type Filter = Box<dyn Fn(&Story) -> bool + Sync>;
+
+pub enum Source {
+    IntFn(Box<dyn Fn(&Story) -> i64 + Sync>),
+    StrFn(Box<dyn Fn(&Story) -> &str + Sync>),
+    DtuFn(Box<dyn Fn(&Story) -> &Option<DateTime<Utc>> + Sync>),
+}
+
+pub enum Operator {
+    Exact,
+    Fuzzy,
+    LessThan,
+    MoreThan,
+}
+
+macro_rules! sfn {
+    ($func:expr) => {
+        |_| Source::StrFn(Box::new($func))
+    };
+}
+
+macro_rules! ifn {
+    ($func:expr) => {
+        |_| Source::IntFn(Box::new($func))
+    };
+}
+
+macro_rules! dfn {
+    ($func:expr) => {
+        |_| Source::DtuFn(Box::new($func))
+    };
+}
+
+named!(source<&str, Source>, preceded!(space0, alt!(
+    tag!("id") => { ifn!(|s| s.id as i64) } |
+
+    tag!("story") => { sfn!(|s| &s.title) } |
+    tag!("title") => { sfn!(|s| &s.title) } |
+
+    tag!("description") => { sfn!(|s| &s.description_html) } |
+    tag!("short description") => { sfn!(|s| &s.short_description) } |
+    tag!("url") => { sfn!(|s| &s.url) } |
+
+    tag!("modified") => { dfn!(|s| &s.date_modified) } |
+    tag!("published") => { dfn!(|s| &s.date_published) } |
+    tag!("updated") => { dfn!(|s| &s.date_updated) } |
+
+    tag!("chapters") => { ifn!(|s| s.num_chapters as i64) } |
+    tag!("comments") => { ifn!(|s| s.num_comments as i64) } |
+    tag!("dislikes") => { ifn!(|s| s.num_dislikes as i64) } |
+    tag!("likes") => { ifn!(|s| s.num_likes as i64) } |
+    tag!("total views") => { ifn!(|s| s.total_num_views as i64) } |
+    tag!("views") => { ifn!(|s| s.num_views as i64) } |
+    tag!("words") => { ifn!(|s| s.num_words as i64) } |
+
+    tag!("author") => { sfn!(|s| &s.author.name) } |
+    tag!("author name") => { sfn!(|s| &s.author.name) } |
+
+    tag!("author id") => { ifn!(|s| s.author.id as i64) } |
+    tag!("author joined") => { dfn!(|s| &s.author.date_joined) } |
+
+    tag!("path") => { sfn!(|s| &s.archive.path) } |
+    tag!("archive") => { sfn!(|s| &s.archive.path) } |
+    tag!("archive path") => { sfn!(|s| &s.archive.path) } |
+
+    tag!("entry checked") => { dfn!(|s| &s.archive.date_checked) } |
+    tag!("entry created") => { dfn!(|s| &s.archive.date_created) } |
+    tag!("entry fetched") => { dfn!(|s| &s.archive.date_fetched) } |
+    tag!("entry updated") => { dfn!(|s| &s.archive.date_updated) }
+)));
+
+named!(operator<&str, Operator>, preceded!(space0, alt!(
+    tag!("=") => { |_| Operator::Exact } |
+    tag!(":") => { |_| Operator::Fuzzy } |
+    tag!("<") => { |_| Operator::LessThan } |
+    tag!(">") => { |_| Operator::MoreThan }
+)));
+
+fn unescape(input: &str) -> String {
+    input
+        .replace("\\)", ")")
+        .replace("\\,", ",")
+        .replace("\\|", "|")
+        .replace("\\\\", "\\")
+}
+
+named!(value<&str, &str>,
+    escaped!(none_of!("),|\\"), '\\', one_of!("),|\\"))
+);
+
+named!(target<&str, String>, preceded!(space0,
+    map!(value, |value| unescape(value.trim()))
+));
+
+fn item(input: &str) -> IResult<&str, Filter> {
+    let result = tuple((source, operator, target))(input)?;
+    let (left, (src, op, value)) = result;
+
+    let filter = optimize(src, op, &value).map_err(|e| match e {
+        _ => Err::Failure((input, NomErrorKind::Permutation)),
+    })?;
+
+    Ok((left, filter))
+}
+
+named!(parens<&str, Filter>, alt!(
+    delimited!(
+        preceded!(space0, tag!("(")),
+        preceded!(space0, call!(ofunc)),
+        preceded!(space0, tag!(")"))
+    ) |
+    call!(item)
+));
+
+fn negate(input: &str) -> IResult<&str, Filter> {
+    let (left, filter) = parens(input)?;
+
+    Ok((left, Box::new(move |s| !filter(s))))
+}
+
+named!(nlist<&str, Filter>, preceded!(space0, alt!(
+    preceded!(char('!'), call!(negate)) | call!(parens)
+)));
+
+named!(alist<&str, Vec<Filter>>, separated_nonempty_list!(
+    preceded!(space0, char(',')), call!(nlist)
+));
+
+fn afunc(input: &str) -> IResult<&str, Filter> {
+    let (left, mut filters) = alist(input)?;
+
+    if filters.len() == 1 {
+        return Ok((left, filters.remove(0)));
+    }
+
+    let filter: Filter = Box::new(move |story| {
+        for filter in filters.iter() {
+            if !filter(story) {
+                return false;
+            }
+        }
+
+        true
+    });
+
+    Ok((left, filter))
+}
+
+named!(olist<&str, Vec<Filter>>, separated_nonempty_list!(
+    preceded!(space0, char('|')), call!(afunc)
+));
+
+fn ofunc(input: &str) -> IResult<&str, Filter> {
+    let (left, mut filters) = olist(input)?;
+
+    if filters.len() == 1 {
+        return Ok((left, filters.remove(0)));
+    }
+
+    let filter: Filter = Box::new(move |story| {
+        for filter in filters.iter() {
+            if filter(story) {
+                return true;
+            }
+        }
+
+        false
+    });
+
+    Ok((left, filter))
+}
+
+fn format_error(query: &str, input: &str, error: NomErrorKind) -> String {
+    let description = error.description().to_lowercase();
+    let position = query.len() - input.len();
+
+    format!("Invalid {} at {}", description, position)
+}
+
+fn translate_error(query: &str, error: Err<(&str, NomErrorKind)>) -> Error {
+    let message = match error {
+        Err::Error((i, e)) => format_error(query, i, e),
+        Err::Failure((i, e)) => format_error(query, i, e),
+        Err::Incomplete(_) => String::from("Incomplete input"),
+    };
+
+    Error::query(message)
+}
+
+fn translate_incomplete(query: &str, input: &str) -> Error {
+    let position = query.len() - input.len();
+
+    Error::query(format!("Incomplete input at {}", position))
+}
+
+pub fn parse(query: &str) -> Result<Filter> {
+    match ofunc(query.trim()) {
+        Ok(("", filter)) => Ok(filter),
+        Ok((i, _)) => Err(translate_incomplete(query, i)),
+        Err(e) => Err(translate_error(query, e)),
+    }
+}