From 59636fa68833a4e24ee28a95e1ba6ad2034b4982 Mon Sep 17 00:00:00 2001
From: many <maxime@meilisearch.com>
Date: Thu, 28 Oct 2021 12:13:51 +0200
Subject: [PATCH] Pimp error where no document is provided

---
 .../tests/documents/add_documents.rs          |  6 ++--
 meilisearch-lib/src/document_formats.rs       | 31 +++++++++++++------
 .../src/index_controller/updates/mod.rs       | 13 +++-----
 3 files changed, 30 insertions(+), 20 deletions(-)

diff --git a/meilisearch-http/tests/documents/add_documents.rs b/meilisearch-http/tests/documents/add_documents.rs
index fc27765ab..4363bd29d 100644
--- a/meilisearch-http/tests/documents/add_documents.rs
+++ b/meilisearch-http/tests/documents/add_documents.rs
@@ -695,10 +695,10 @@ async fn error_add_no_documents() {
     let (response, code) = index.add_documents(json!([]), None).await;
 
     let expected_response = json!({
-        "message": "A json payload is missing.",
-        "code": "missing_payload",
+        "message": "The `json` payload must contain at least one document.",
+        "code": "malformed_payload",
         "type": "invalid_request",
-        "link": "https://docs.meilisearch.com/errors#missing_payload"
+        "link": "https://docs.meilisearch.com/errors#malformed_payload"
     });
 
     assert_eq!(response, expected_response);
diff --git a/meilisearch-lib/src/document_formats.rs b/meilisearch-lib/src/document_formats.rs
index 9ddbdf09d..137ecc280 100644
--- a/meilisearch-lib/src/document_formats.rs
+++ b/meilisearch-lib/src/document_formats.rs
@@ -32,6 +32,8 @@ pub enum DocumentFormatError {
         Box<dyn std::error::Error + Send + Sync + 'static>,
         PayloadType,
     ),
+    #[error("The `{0}` payload must contain at least one document.")]
+    EmptyPayload(PayloadType),
 }
 
 impl From<(PayloadType, milli::documents::Error)> for DocumentFormatError {
@@ -48,6 +50,7 @@ impl ErrorCode for DocumentFormatError {
         match self {
             DocumentFormatError::Internal(_) => Code::Internal,
             DocumentFormatError::MalformedPayload(_, _) => Code::MalformedPayload,
+            DocumentFormatError::EmptyPayload(_) => Code::MalformedPayload,
         }
     }
 }
@@ -55,18 +58,22 @@ impl ErrorCode for DocumentFormatError {
 internal_error!(DocumentFormatError: io::Error);
 
 /// reads csv from input and write an obkv batch to writer.
-pub fn read_csv(input: impl Read, writer: impl Write + Seek) -> Result<usize> {
+pub fn read_csv(input: impl Read, writer: impl Write + Seek) -> Result<()> {
     let writer = BufWriter::new(writer);
     let builder =
         DocumentBatchBuilder::from_csv(input, writer).map_err(|e| (PayloadType::Csv, e))?;
-    let document_count = builder.len();
+
+    if builder.len() == 0 {
+        return Err(DocumentFormatError::EmptyPayload(PayloadType::Csv));
+    }
+
     builder.finish().map_err(|e| (PayloadType::Csv, e))?;
 
-    Ok(document_count)
+    Ok(())
 }
 
 /// reads jsonl from input and write an obkv batch to writer.
-pub fn read_ndjson(input: impl Read, writer: impl Write + Seek) -> Result<usize> {
+pub fn read_ndjson(input: impl Read, writer: impl Write + Seek) -> Result<()> {
     let mut reader = BufReader::new(input);
     let writer = BufWriter::new(writer);
 
@@ -80,22 +87,28 @@ pub fn read_ndjson(input: impl Read, writer: impl Write + Seek) -> Result<usize>
         buf.clear();
     }
 
-    let document_count = builder.len();
+    if builder.len() == 0 {
+        return Err(DocumentFormatError::EmptyPayload(PayloadType::Ndjson));
+    }
 
     builder.finish().map_err(|e| (PayloadType::Ndjson, e))?;
 
-    Ok(document_count)
+    Ok(())
 }
 
 /// reads json from input and write an obkv batch to writer.
-pub fn read_json(input: impl Read, writer: impl Write + Seek) -> Result<usize> {
+pub fn read_json(input: impl Read, writer: impl Write + Seek) -> Result<()> {
     let writer = BufWriter::new(writer);
     let mut builder = DocumentBatchBuilder::new(writer).map_err(|e| (PayloadType::Json, e))?;
     builder
         .extend_from_json(input)
         .map_err(|e| (PayloadType::Json, e))?;
-    let document_count = builder.len();
+
+    if builder.len() == 0 {
+        return Err(DocumentFormatError::EmptyPayload(PayloadType::Json));
+    }
+
     builder.finish().map_err(|e| (PayloadType::Json, e))?;
 
-    Ok(document_count)
+    Ok(())
 }
diff --git a/meilisearch-lib/src/index_controller/updates/mod.rs b/meilisearch-lib/src/index_controller/updates/mod.rs
index 3f2a2ef32..07ceed92b 100644
--- a/meilisearch-lib/src/index_controller/updates/mod.rs
+++ b/meilisearch-lib/src/index_controller/updates/mod.rs
@@ -174,18 +174,15 @@ impl UpdateLoop {
                     }
 
                     let reader = Cursor::new(buffer);
-                    let document_count = match format {
+                    match format {
                         DocumentAdditionFormat::Json => read_json(reader, &mut *update_file)?,
                         DocumentAdditionFormat::Csv => read_csv(reader, &mut *update_file)?,
                         DocumentAdditionFormat::Ndjson => read_ndjson(reader, &mut *update_file)?,
-                    };
-
-                    if document_count > 0 {
-                        update_file.persist()?;
-                        Ok(())
-                    } else {
-                        Err(UpdateLoopError::MissingPayload(format))
                     }
+
+                    update_file.persist()?;
+
+                    Ok(())
                 })
                 .await??;