{"record":{"id":"35354a75443ce7a8","repo":"Pumpkin-MC/Pumpkin","slug":"failed-to-serialize-packet-0","errorCode":null,"errorMessage":"Failed to serialize packet: {0}","messagePattern":"Failed to serialize packet: (.+?)","errorType":"exception","errorClass":"WritingError","httpStatus":null,"severity":"error","filePath":"crates/pumpkin-protocol/src/ser/mod.rs","lineNumber":45,"sourceCode":"    #[error(\"{0}\")]\n    Message(String),\n}\n\nimpl serde::de::Error for ReadingError {\n    fn custom<T: std::fmt::Display>(msg: T) -> Self {\n        Self::Message(msg.to_string())\n    }\n}\n\n#[derive(Debug, Error)]\npub enum WritingError {\n    #[error(\"IO error: {0}\")]\n    IoError(#[from] std::io::Error),\n    #[error(\"Serde failure: {0}\")]\n    Serde(String),\n    #[error(\"Packet is not supported in Minecraft version {0:?}\")]\n    UnsupportedVersion(JavaMinecraftVersion),\n    #[error(\"Failed to serialize packet: {0}\")]\n    Message(String),\n}\n\nimpl serde::ser::Error for WritingError {\n    fn custom<T: std::fmt::Display>(msg: T) -> Self {\n        Self::Serde(msg.to_string())\n    }\n}\n\nstruct NetworkReadDataSource<'a, R: NetworkReadExt + ?Sized>(&'a mut R);\n\nimpl<'a, R: NetworkReadExt + ?Sized> pumpkin_nbt::deserializer::NbtDataSource<'a>\n    for NetworkReadDataSource<'a, R>\n{\n    fn read_u8(&mut self) -> Result<u8, pumpkin_nbt::Error> {\n        self.0.get_u8().map_err(|e| {\n            pumpkin_nbt::Error::Incomplete(std::io::Error::new(\n                std::io::ErrorKind::UnexpectedEof,","sourceCodeStart":27,"sourceCodeEnd":63,"githubUrl":"https://github.com/Pumpkin-MC/Pumpkin/blob/8d4639e25a57c15e47448ec327c780d41bbf2356/crates/pumpkin-protocol/src/ser/mod.rs#L27-L63","documentation":"WritingError::Message(String) is the generic fallback variant of the writing error enum, used for packet-level serialization failures that are not IO, not serde-custom, and not version gating — for example a packet implementation explicitly reporting that it could not serialize its own fields. It carries a free-form description of what failed.","triggerScenarios":"A packet's write/serialize implementation constructs Message directly when its internal encoding steps fail (e.g. malformed state machine, missing required sub-field, or a wrapper that flattens heterogeneous encode errors into the writing error).","commonSituations":"Custom or third-party packet implementations reporting internal failures; misuse of packet-builder APIs leaving required fields unset; wrappers converting lower-level errors into a string and re-raising as Message.","solutions":["Read the message text — it is produced by the packet implementation and names the failure.","Ensure all required fields are populated before writing the packet.","Check for newer library versions if the failing packet is a built-in one; the implementation may have a fix.","If you wrote the packet type, return a more specific WritingError variant instead of a bare string."],"exampleFix":"// before: packet built with a required field left default\nlet p = Packet::default();\np.write(stream).await?; // \"failed to serialize packet: missing field\"\n\n// after: construct explicitly with all fields\nlet p = Packet { id, state, data: payload };\np.write(stream).await?;","handlingStrategy":"try-catch","validationCode":"// ensure every required packet field is set before writing\nfn packet_ready(p: &Packet) -> bool { p.id != 0 && !p.data.is_empty() }","typeGuard":null,"tryCatchPattern":"match packet.write(&mut stream).await {\n    Err(WritingError::Message(msg)) => {\n        error!(\"packet serialization failed: {msg}\");\n        // fix construction site; connection can usually stay open\n    }\n    other => /* ... */,\n}","preventionTips":["Construct packets with explicit builders/struct literals instead of default().","Handle the error at the send site; the message names the failing packet logic.","Prefer specific error variants in your own packet implementations for better diagnostics."],"tags":["rust","serialization","protocol","serde"],"backgroundTag":"json-serialization-failed","analyzedSha":"8d4639e25a57c15e47448ec327c780d41bbf2356","analyzedAt":"2026-09-09T15:32:22.916Z","contentChangedAt":"2026-09-09T15:32:22.916Z","schemaVersion":2},"datasetVersion":"2026-09-16T04:17:20.429Z"}