chore (backend-rs): improve error messages

refs:
https://rust-lang.github.io/api-guidelines/interoperability.html
https://github.com/rust-lang/project-error-handling/issues/27

packages/backend-rs/src/database/cache.rs

@@ -15,11 +15,11 @@ pub enum Category {
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Redis error: {0}")]
+    #[error("failed to execute Redis command")]
     Redis(#[from] RedisError),
-    #[error("Redis connection error: {0}")]
+    #[error("bad Redis connection")]
     RedisConn(#[from] RedisConnError),
-    #[error("Failed to encode the data: {0}")]
+    #[error("failed to encode data for Redis")]
     Encode(#[from] rmp_serde::encode::Error),
 }
 

packages/backend-rs/src/database/redis.rs

@@ -81,9 +81,9 @@ async fn init_conn_pool() -> Result<(), RedisError> {
 
 #[derive(thiserror::Error, Debug)]
 pub enum RedisConnError {
-    #[error("Failed to initialize Redis connection pool: {0}")]
+    #[error("failed to initialize Redis connection pool")]
     Redis(RedisError),
-    #[error("Redis connection pool error: {0}")]
+    #[error("bad Redis connection pool")]
     Bb8Pool(RunError<RedisError>),
 }
 

packages/backend-rs/src/federation/acct.rs

@@ -8,6 +8,7 @@ pub struct Acct {
 }
 
 #[derive(thiserror::Error, Debug)]
+#[doc = "Error type to indicate a string-to-[`Acct`] conversion failure"]
 #[error("failed to convert string '{0}' into acct")]
 pub struct InvalidAcctString(String);
 

packages/backend-rs/src/federation/nodeinfo/fetch.rs

@@ -9,17 +9,18 @@ use serde::Deserialize;
 /// Errors that can occur while fetching NodeInfo from a remote server
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("HTTP client aquisition error: {0}")]
+    #[error("failed to acquire an HTTP client")]
     HttpClient(#[from] http_client::Error),
-    #[error("HTTP error: {0}")]
+    #[error("HTTP request failed")]
     Http(#[from] isahc::Error),
-    #[error("Bad status: {0}")]
+    #[doc = "bad HTTP status"]
+    #[error("bad HTTP status ({0})")]
     BadStatus(String),
-    #[error("Failed to parse response body as text: {0}")]
+    #[error("failed to parse HTTP response body as text")]
     Response(#[from] std::io::Error),
-    #[error("Failed to parse response body as json: {0}")]
+    #[error("failed to parse HTTP response body as json")]
     Json(#[from] serde_json::Error),
-    #[error("No nodeinfo provided")]
+    #[error("nodeinfo is missing")]
     MissingNodeinfo,
 }
 

packages/backend-rs/src/federation/nodeinfo/generate.rs

@@ -154,9 +154,10 @@ pub async fn nodeinfo_2_0() -> Result<Nodeinfo20, DbErr> {
 #[cfg(feature = "napi")]
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Database error: {0}")]
+    #[doc = "database error"]
+    #[error(transparent)]
     Db(#[from] DbErr),
-    #[error("Failed to serialize nodeinfo into JSON: {0}")]
+    #[error("failed to serialize nodeinfo into JSON")]
     Json(#[from] serde_json::Error),
 }
 

packages/backend-rs/src/misc/convert_host.rs

@@ -4,11 +4,12 @@
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Idna error: {0}")]
+    #[doc = "UTS #46 process has failed"]
+    #[error(transparent)]
     Idna(#[from] idna::Errors),
-    #[error("Url parse error: {0}")]
+    #[error("failed to parse a URL")]
     UrlParse(#[from] url::ParseError),
-    #[error("Hostname is missing")]
+    #[error("hostname is missing")]
     NoHostname,
 }
 

packages/backend-rs/src/misc/get_image_size.rs

@@ -7,23 +7,26 @@ use tokio::sync::Mutex;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Redis cache error: {0}")]
+    #[error("Redis cache operation has failed")]
     Cache(#[from] cache::Error),
-    #[error("HTTP client aquisition error: {0}")]
+    #[error("failed to acquire an HTTP client")]
     HttpClient(#[from] http_client::Error),
-    #[error("Isahc error: {0}")]
+    #[error("HTTP request failed")]
     Isahc(#[from] isahc::Error),
-    #[error("HTTP error: {0}")]
-    Http(String),
-    #[error("Image decoding error: {0}")]
+    #[doc = "bad HTTP status"]
+    #[error("bad HTTP status ({0})")]
+    BadStatus(String),
+    #[error("failed to decode an image")]
     Image(#[from] ImageError),
-    #[error("Image decoding error: {0}")]
+    #[error("failed to decode an image")]
     Io(#[from] std::io::Error),
-    #[error("Exif extraction error: {0}")]
+    #[error("failed to extract the exif data")]
     Exif(#[from] nom_exif::Error),
-    #[error("Emoji meta attempt limit exceeded: {0}")]
+    #[doc = "too many fetch attempts"]
+    #[error("too many fetch attempts for {0}")]
     TooManyAttempts(String),
-    #[error("Unsupported image type: {0}")]
+    #[doc = "unsupported image type"]
+    #[error("unsupported image type ({0})")]
     UnsupportedImage(String),
 }
 
@@ -75,7 +78,11 @@ pub async fn get_image_size_from_url(url: &str) -> Result<ImageSize, Error> {
     if !response.status().is_success() {
         tracing::info!("status: {}", response.status());
         tracing::debug!("response body: {:#?}", response.body());
-        return Err(Error::Http(format!("Failed to get image from {}", url)));
+        return Err(Error::BadStatus(format!(
+            "{} returned {}",
+            url,
+            response.status()
+        )));
     }
 
     let image_bytes = response.bytes().await?;

packages/backend-rs/src/misc/latest_version.rs

@@ -6,17 +6,18 @@ use serde::Deserialize;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Cache error: {0}")]
+    #[error("Redis cache operation has failed")]
     Cache(#[from] cache::Error),
-    #[error("Isahc error: {0}")]
+    #[error("HTTP request failed")]
     Isahc(#[from] isahc::Error),
-    #[error("HTTP client aquisition error: {0}")]
+    #[error("failed to acquire an HTTP client")]
     HttpClient(#[from] http_client::Error),
-    #[error("HTTP error: {0}")]
-    Http(String),
-    #[error("Response parsing error: {0}")]
+    #[doc = "firefish.dev returned bad HTTP status"]
+    #[error("firefish.dev returned bad HTTP status ({0})")]
+    BadStatus(String),
+    #[error("failed to parse the HTTP response")]
     Io(#[from] std::io::Error),
-    #[error("Failed to deserialize JSON: {0}")]
+    #[error("failed to parse the HTTP response as JSON")]
     Json(#[from] serde_json::Error),
 }
 
@@ -36,9 +37,7 @@ async fn get_latest_version() -> Result<String, Error> {
     if !response.status().is_success() {
         tracing::info!("status: {}", response.status());
         tracing::debug!("response body: {:#?}", response.body());
-        return Err(Error::Http(
-            "Failed to fetch version from Firefish GitLab".to_string(),
-        ));
+        return Err(Error::BadStatus(response.status().to_string()));
     }
 
     let res_parsed: Response = serde_json::from_str(&response.text().await?)?;

packages/backend-rs/src/misc/password.rs

@@ -17,12 +17,12 @@ pub fn hash_password(password: &str) -> Result<String, password_hash::errors::Er
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("An error occured while bcrypt verification: {0}")]
+    #[error("failed to verify password against bcrypt hash")]
     Bcrypt(#[from] bcrypt::BcryptError),
-    #[error("Invalid argon2 password hash: {0}")]
-    InvalidArgon2Hash(#[from] password_hash::Error),
-    #[error("An error occured while argon2 verification: {0}")]
+    #[error("failed to verify password against argon2 hash")]
     Argon2(#[from] argon2::Error),
+    #[error("invalid argon2 password hash")]
+    InvalidArgon2Hash(#[from] password_hash::Error),
 }
 
 /// Checks whether the given password and hash match.

packages/backend-rs/src/misc/reaction.rs

@@ -55,9 +55,10 @@ pub fn count_reactions(reactions: &HashMap<String, u32>) -> HashMap<String, u32>
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Idna error: {0}")]
+    #[doc = "UTS #46 process has failed"]
+    #[error(transparent)]
     Idna(#[from] idna::Errors),
-    #[error("Database error: {0}")]
+    #[error(transparent)]
     Db(#[from] DbErr),
 }
 

packages/backend-rs/src/service/antenna/check_hit.rs

@@ -8,9 +8,10 @@ use sea_orm::{prelude::*, QuerySelect};
 
 #[derive(thiserror::Error, Debug)]
 pub enum AntennaCheckError {
-    #[error("Database error: {0}")]
+    #[doc = "database error"]
+    #[error(transparent)]
     Db(#[from] DbErr),
-    #[error("Cache error: {0}")]
+    #[error("Redis cache operation has failed")]
     Cache(#[from] cache::Error),
 }
 

packages/backend-rs/src/service/antenna/process_new_note.rs

@@ -15,19 +15,21 @@ use sea_orm::prelude::*;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Database error: {0}")]
+    #[doc = "database error"]
+    #[error(transparent)]
     Db(#[from] DbErr),
-    #[error("Cache error: {0}")]
+    #[error("Redis cache operation has failed")]
     Cache(#[from] cache::Error),
-    #[error("Redis error: {0}")]
+    #[error("failed to execute a Redis command")]
     Redis(#[from] RedisError),
-    #[error("Redis connection error: {0}")]
+    #[error("bad Redis connection")]
     RedisConn(#[from] RedisConnError),
-    #[error("Invalid ID: {0}")]
+    #[doc = "provided string is not a valid Firefish ID"]
+    #[error(transparent)]
     InvalidId(#[from] InvalidIdError),
-    #[error("Stream error: {0}")]
+    #[error("Redis stream operation has failed")]
     Stream(#[from] stream::Error),
-    #[error("Failed to check if the note should be added to antenna: {0}")]
+    #[error("failed to check if the note should be added to antenna")]
     AntennaCheck(#[from] AntennaCheckError),
 }
 

packages/backend-rs/src/service/push_notification.rs

@@ -9,15 +9,17 @@ use web_push::*;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Database error: {0}")]
+    #[doc = "database error"]
+    #[error(transparent)]
     Db(#[from] DbErr),
-    #[error("Web Push error: {0}")]
+    #[error("web push has failed")]
     WebPush(#[from] WebPushError),
-    #[error("Failed to (de)serialize an object: {0}")]
+    #[error("failed to (de)serialize an object")]
     Serialize(#[from] serde_json::Error),
-    #[error("Invalid content: {0}")]
+    #[doc = "provided content is invalid"]
+    #[error("invalid content ({0})")]
     InvalidContent(String),
-    #[error("HTTP client aquisition error: {0}")]
+    #[error("failed to acquire an HTTP client")]
     HttpClient(#[from] http_client::Error),
 }
 

packages/backend-rs/src/service/stream.rs

@@ -62,14 +62,14 @@ pub enum ChatEvent {
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Redis error: {0}")]
+    #[error("failed to execute a Redis command")]
     Redis(#[from] RedisError),
-    #[error("Redis connection error: {0}")]
+    #[error("bad Redis connection")]
     RedisConn(#[from] RedisConnError),
-    #[error("Json (de)serialization error: {0}")]
+    #[error("failed to (de)serialize object")]
     Json(#[from] serde_json::Error),
-    #[error("Value error: {0}")]
-    Value(String),
+    #[error("invalid content")]
+    InvalidContent,
 }
 
 pub async fn publish_to_stream(
@@ -104,7 +104,7 @@ pub async fn publish_to_stream(
             value.unwrap_or_else(|| "null".to_string()),
         )
     } else {
-        value.ok_or(Error::Value("Invalid streaming message".to_string()))?
+        value.ok_or(Error::InvalidContent)?
     };
 
     redis_conn()

packages/backend-rs/src/util/http_client.rs

@@ -7,9 +7,9 @@ use std::time::Duration;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("Isahc error: {0}")]
+    #[error("HTTP request failed")]
     Isahc(#[from] isahc::Error),
-    #[error("Url parse error: {0}")]
+    #[error("invalid URL")]
     UrlParse(#[from] isahc::http::uri::InvalidUri),
 }
 

packages/backend-rs/src/util/id.rs

@@ -46,7 +46,8 @@ fn create_id(datetime: &NaiveDateTime) -> String {
 }
 
 #[derive(thiserror::Error, Debug)]
-#[error("Invalid ID: {id}")]
+#[doc = "Error type to indicate invalid Firefish ID"]
+#[error("'{id}' is not a valid Firefish ID")]
 pub struct InvalidIdError {
     id: String,
 }