From 5051a796a082877dd84e445ab769951af3245a83 Mon Sep 17 00:00:00 2001
From: mpostma <postma.marin@protonmail.com>
Date: Tue, 12 May 2020 14:26:43 +0200
Subject: [PATCH] error handling

---
 meilisearch-http/src/error.rs         | 59 +++++++++++++++++++++++----
 meilisearch-http/src/routes/search.rs | 11 +++--
 2 files changed, 55 insertions(+), 15 deletions(-)

diff --git a/meilisearch-http/src/error.rs b/meilisearch-http/src/error.rs
index e79cb56b6..eee9d8e8e 100644
--- a/meilisearch-http/src/error.rs
+++ b/meilisearch-http/src/error.rs
@@ -27,6 +27,40 @@ pub enum ResponseError {
     PayloadTooLarge,
     UnsupportedMediaType,
     FacetExpression(String),
+    FacetCount(String),
+}
+
+pub enum FacetCountError {
+    AttributeNotSet(String),
+    SyntaxError(String),
+    UnexpectedToken { found: String, expected: &'static [&'static str] },
+    NoFacetSet,
+}
+
+impl FacetCountError {
+    pub fn unexpected_token(found: impl ToString, expected: &'static [&'static str]) -> FacetCountError {
+        let found = found.to_string();
+        FacetCountError::UnexpectedToken { expected, found }
+    }
+}
+
+impl From<serde_json::error::Error> for FacetCountError {
+    fn from(other: serde_json::error::Error) -> FacetCountError {
+        FacetCountError::SyntaxError(other.to_string())
+    }
+}
+
+impl fmt::Display for FacetCountError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        use FacetCountError::*;
+
+        match self {
+            AttributeNotSet(attr) => write!(f, "attribute {} is not set as facet", attr),
+            SyntaxError(msg) => write!(f, "syntax error: {}", msg),
+            UnexpectedToken { expected, found } => write!(f, "unexpected {} found, expected {:?}", found, expected),
+            NoFacetSet => write!(f, "can't perform facet count, as no facet is set"),
+        }
+    }
 }
 
 impl ResponseError {
@@ -113,6 +147,7 @@ impl fmt::Display for ResponseError {
             Self::FacetExpression(e) => write!(f, "error parsing facet filter expression: {}", e),
             Self::PayloadTooLarge => f.write_str("Payload to large"),
             Self::UnsupportedMediaType => f.write_str("Unsupported media type")
+            Self::FacetCount(e) => write!(f, "error with facet count: {}", e),
         }
     }
 }
@@ -134,6 +169,7 @@ impl aweb::error::ResponseError for ResponseError {
             | Self::RetrieveDocument(_, _)
             | Self::FacetExpression(_)
             | Self::SearchDocuments(_)
+            | Self::FacetCount(_)
             | Self::FilterParsing(_) => StatusCode::BAD_REQUEST,
             Self::DocumentNotFound(_)
             | Self::IndexNotFound(_)
@@ -198,18 +234,23 @@ impl From<actix_http::Error> for ResponseError {
     }
 }
 
-impl From<JsonPayloadError> for ResponseError {
-    fn from(err: JsonPayloadError) -> ResponseError {
-        match err {
-                JsonPayloadError::Deserialize(err) => ResponseError::BadRequest(format!("Invalid JSON: {}", err)),
-                JsonPayloadError::Overflow => ResponseError::PayloadTooLarge,
-                JsonPayloadError::ContentType => ResponseError::UnsupportedMediaType,
-                JsonPayloadError::Payload(err) => ResponseError::BadRequest(format!("Problem while decoding the request: {}", err)),
-            }
+impl From<FacetCountError> for ResponseError {
+    fn from(other: FacetCountError) -> ResponseError {
+        ResponseError::FacetCount(other.to_string())
     }
 }
 
+impl From<JsonPayloadError> for ResponseError {
+    fn from(err: JsonPayloadError) -> ResponseError {
+        match err {
+            JsonPayloadError::Deserialize(err) => ResponseError::BadRequest(format!("Invalid JSON: {}", err)),
+            JsonPayloadError::Overflow => ResponseError::PayloadTooLarge,
+            JsonPayloadError::ContentType => ResponseError::UnsupportedMediaType,
+            JsonPayloadError::Payload(err) => ResponseError::BadRequest(format!("Problem while decoding the request: {}", err)),
+        }
+    }
+}
 
 pub fn json_error_handler(err: JsonPayloadError) -> ResponseError {
-	err.into()
+    err.into()
 }
diff --git a/meilisearch-http/src/routes/search.rs b/meilisearch-http/src/routes/search.rs
index 5d086d128..7739ea1d8 100644
--- a/meilisearch-http/src/routes/search.rs
+++ b/meilisearch-http/src/routes/search.rs
@@ -7,7 +7,7 @@ use actix_web_macros::get;
 use serde::Deserialize;
 use serde_json::Value;
 
-use crate::error::ResponseError;
+use crate::error::{ResponseError, FacetCountError};
 use crate::helpers::meilisearch::IndexSearchExt;
 use crate::helpers::Authentication;
 use crate::routes::IndexParam;
@@ -100,9 +100,8 @@ async fn search_with_url_query(
                 let field_ids = prepare_facet_list(&facets, &schema, attrs)?;
                 search_builder.add_facets(field_ids);
             },
-            None => return Err(ResponseError::FacetExpression("can't return facets count, as no facet is set".to_string()))
+            None => return Err(FacetCountError::NoFacetSet.into())
         }
-
     }
 
     if let Some(attributes_to_crop) = &params.attributes_to_crop {
@@ -188,16 +187,16 @@ fn prepare_facet_list(facets: &str, schema: &Schema, facet_attrs: &[FieldId]) ->
                     Value::String(facet) => {
                         if let Some(id) = schema.id(&facet) {
                             if !facet_attrs.contains(&id) {
-                                return Err(ResponseError::FacetExpression("Only attributes set as facet can be counted".to_string())); // TODO make special error
+                                return Err(FacetCountError::AttributeNotSet(facet));
                             }
                             field_ids.push((id, facet));
                         }
                     }
-                    bad_val => return Err(ResponseError::FacetExpression(format!("expected String found {}", bad_val)))
+                    bad_val => return Err(FacetCountError::unexpected_token(bad_val, &["String"])),
                 }
             }
             Ok(field_ids)
         }
-        bad_val => return Err(ResponseError::FacetExpression(format!("expected Array found {}", bad_val)))
+        bad_val => return Err(FacetCountError::unexpected_token(bad_val, &["[String]"]))
     }
 }