From 110adcae857b3d229ceb1b9ada9e7021672088db Mon Sep 17 00:00:00 2001
From: qdequele <quentin@dequelen.me>
Date: Thu, 2 Jan 2020 18:08:52 +0100
Subject: [PATCH] Remove the schema; fix #422

---
 .../src/update/documents_addition.rs          | 42 ++++++++++++++++++-
 meilisearch-schema/src/lib.rs                 |  2 +-
 2 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/meilisearch-core/src/update/documents_addition.rs b/meilisearch-core/src/update/documents_addition.rs
index ec45b40ad..5c14000b8 100644
--- a/meilisearch-core/src/update/documents_addition.rs
+++ b/meilisearch-core/src/update/documents_addition.rs
@@ -1,8 +1,9 @@
-use std::collections::HashMap;
+use std::collections::{HashMap, BTreeSet};
 
 use fst::{set::OpBuilder, SetBuilder};
 use sdset::{duo::Union, SetOperation};
 use serde::{Deserialize, Serialize};
+use meilisearch_schema::{Schema, DISPLAYED, INDEXED};
 
 use crate::database::{MainT, UpdateT};
 use crate::database::{UpdateEvent, UpdateEventsEmitter};
@@ -114,6 +115,11 @@ pub fn apply_documents_addition<'a, 'b>(
         None => return Err(Error::SchemaMissing),
     };
 
+    if let Some(new_schema) = lazy_new_schema(&schema, &addition) {
+        main_store.put_schema(writer, &new_schema)?;
+        schema = new_schema;
+    }
+
     let identifier = schema.identifier_name();
 
     // 1. store documents ids for future deletion
@@ -178,11 +184,16 @@ pub fn apply_documents_partial_addition<'a, 'b>(
 ) -> MResult<()> {
     let mut documents_additions = HashMap::new();
 
-    let schema = match index.main.schema(writer)? {
+
         Some(schema) => schema,
         None => return Err(Error::SchemaMissing),
     };
 
+    if let Some(new_schema) = lazy_new_schema(&schema, &addition) {
+        main_store.put_schema(writer, &new_schema)?;
+        schema = new_schema;
+    }
+
     let identifier = schema.identifier_name();
 
     // 1. store documents ids for future deletion
@@ -382,3 +393,30 @@ pub fn write_documents_addition_index(
 
     Ok(())
 }
+
+pub fn lazy_new_schema(
+    schema: &Schema,
+    documents: &[HashMap<String, serde_json::Value>],
+) -> Option<Schema> {
+    let mut attributes_to_add = BTreeSet::new();
+
+    for document in documents {
+        for (key, _) in document {
+            if schema.attribute(key).is_none() {
+                attributes_to_add.insert(key);
+            }
+        }
+    }
+
+    if attributes_to_add.is_empty() {
+        return None
+    }
+
+    let mut schema_builder = schema.to_builder();
+    for attribute in attributes_to_add {
+        schema_builder.new_attribute(attribute, DISPLAYED | INDEXED);
+    }
+    let schema = schema_builder.build();
+
+    Some(schema)
+}
diff --git a/meilisearch-schema/src/lib.rs b/meilisearch-schema/src/lib.rs
index 929316d41..a7125e434 100644
--- a/meilisearch-schema/src/lib.rs
+++ b/meilisearch-schema/src/lib.rs
@@ -145,7 +145,7 @@ struct InnerSchema {
 }
 
 impl Schema {
-    fn to_builder(&self) -> SchemaBuilder {
+    pub fn to_builder(&self) -> SchemaBuilder {
         let identifier = self.inner.identifier.clone();
         let attributes = self.attributes_ordered();
         SchemaBuilder {