Merge #515

515: Improve the README r=curquiza a=Kerollmops

This PR closes #512 by adding more content to the README. We listed all of the subcrates of the repository, changed the descriptions of the subcrates, and added a simple example usage in the README.

Co-authored-by: Kerollmops <clement@meilisearch.com>
Co-authored-by: Clémentine Urquizar - curqui <clementine@meilisearch.com>

README.md

@@ -15,14 +15,78 @@ to process one update at a time.
 
 This repository contains crates to quickly debug the engine:
  - There are benchmarks located in the `benchmarks` crate.
- - The `http-ui` crate is a simple HTTP dashboard to tests the features like for real!
+ - The `cli` crate is a simple command-line interface that helps run [flamegraph] on top of it.
+ - The `filter-parser` crate contains the parser for the Meilisearch filter syntax.
+ - The `flatten-serde-json` crate contains the library that flattens serde-json `Value` objects like Elasticsearch does.
+ - The `helpers` crate is only used to do operations on the database.
+ - The `http-ui` crate is a simple HTTP dashboard to test the features like for real!
  - The `infos` crate is used to dump the internal data-structure and ensure correctness.
- - The `search` crate is a simple command-line that helps run [flamegraph] on top of it.
- - The `helpers` crate is only used to modify the database inplace, sometimes.
+ - The `json-depth-checker` crate is used to indicate if a JSON must be flattened.
 
 ## How to use it?
 
-_Section in WIP_
+Milli is a library that does search things, it must be embedded in a program.
+You can compute the documentation of it by using `cargo doc --open`.
+
+Here is an example usage of the library where we insert documents into the engine
+and search for one of them right after.
+
+```rust
+let path = tempfile::tempdir().unwrap();
+let mut options = EnvOpenOptions::new();
+options.map_size(10 * 1024 * 1024); // 10 MB
+let index = Index::new(options, &path).unwrap();
+
+let mut wtxn = index.write_txn().unwrap();
+let content = documents!([
+    {
+        "id": 2,
+        "title": "Prideand Prejudice",
+        "au{hor": "Jane Austin",
+        "genre": "romance",
+        "price$": "3.5$",
+    },
+    {
+        "id": 456,
+        "title": "Le Petit Prince",
+        "au{hor": "Antoine de Saint-Exupéry",
+        "genre": "adventure",
+        "price$": "10.0$",
+    },
+    {
+        "id": 1,
+        "title": "Wonderland",
+        "au{hor": "Lewis Carroll",
+        "genre": "fantasy",
+        "price$": "25.99$",
+    },
+    {
+        "id": 4,
+        "title": "Harry Potter ing fantasy\0lood Prince",
+        "au{hor": "J. K. Rowling",
+        "genre": "fantasy\0",
+    },
+]);
+
+let config = IndexerConfig::default();
+let indexing_config = IndexDocumentsConfig::default();
+let mut builder =
+    IndexDocuments::new(&mut wtxn, &index, &config, indexing_config.clone(), |_| ())
+        .unwrap();
+builder.add_documents(content).unwrap();
+builder.execute().unwrap();
+wtxn.commit().unwrap();
+
+
+// You can search in the index now!
+let mut rtxn = index.read_txn().unwrap();
+let mut search = Search::new(&rtxn, &index);
+search.query("horry");
+search.limit(10);
+
+let result = search.execute().unwrap();
+assert_eq!(result.documents_ids.len(), 1);
+```
 
 ## Contributing
 

cli/Cargo.toml

@@ -4,8 +4,6 @@ version = "0.26.1"
 edition = "2018"
 description = "A CLI to interact with a milli index"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
 indicatif = "0.16.2"
 serde = "1.0.136"

filter-parser/Cargo.toml

@@ -2,8 +2,7 @@
 name = "filter-parser"
 version = "0.1.0"
 edition = "2021"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+description = "The parser for the Meilisearch filter syntax"
 
 [dependencies]
 nom = "7.1.0"

helpers/Cargo.toml

@@ -3,6 +3,7 @@ name = "helpers"
 version = "0.26.1"
 authors = ["Clément Renault <clement@meilisearch.com>"]
 edition = "2018"
+description = "A small tool to do operations on the database"
 
 [dependencies]
 anyhow = "1.0.56"

json-depth-checker/Cargo.toml

@@ -2,8 +2,7 @@
 name = "json-depth-checker"
 version = "0.1.0"
 edition = "2021"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+description = "A library that indicates if a JSON must be flattened"
 
 [dependencies]
 serde_json = "1.0"

json-depth-checker/src/lib.rs

@@ -1,6 +1,6 @@
 use serde_json::Value;
 
-/// Your json MUST BE valid and generated by `serde_json::to_vec` before being
+/// Your json MUST BE valid and generated by `serde_json::to_vec` before being
 /// sent in this function. This function is DUMB and FAST but makes a lot of
 /// asumption about the way `serde_json` will generate its input.
 ///