{"record":{"id":"8a9795165074a6ac","repo":"apache/seatunnel","slug":"failed-to-serialize-checkpoint-data-state-stat","errorCode":null,"errorMessage":"Failed to serialize checkpoint data, state: ${state}","messagePattern":"Failed to serialize checkpoint data, state: (.+?)","errorType":"exception","errorClass":"CheckpointStorageException","httpStatus":null,"severity":"error","filePath":"seatunnel-engine/seatunnel-engine-storage/checkpoint-storage-plugins/checkpoint-storage-hdfs/src/main/java/org/apache/seatunnel/engine/checkpoint/storage/hdfs/HdfsStorage.java","lineNumber":91,"sourceCode":"    }\n\n    private Configuration getConfiguration(Map<String, String> config)\n            throws CheckpointStorageException {\n        String storageType =\n                config.getOrDefault(STORAGE_TYPE_KEY, FileConfiguration.LOCAL.toString());\n        config.remove(STORAGE_TYPE_KEY);\n        AbstractConfiguration configuration =\n                FileConfiguration.valueOf(storageType.toUpperCase()).getConfiguration();\n        return configuration.buildConfiguration(config);\n    }\n\n    @Override\n    public String storeCheckPoint(PipelineState state) throws CheckpointStorageException {\n        byte[] datas;\n        try {\n            datas = serializeCheckPointData(state);\n        } catch (IOException e) {\n            throw new CheckpointStorageException(\n                    String.format(\"Failed to serialize checkpoint data, state: %s\", state), e);\n        }\n        Path filePath =\n                new Path(\n                        getStorageParentDirectory()\n                                + state.getJobId()\n                                + \"/\"\n                                + getCheckPointName(state));\n\n        Path tmpFilePath =\n                new Path(\n                        getStorageParentDirectory()\n                                + state.getJobId()\n                                + \"/\"\n                                + getCheckPointName(state)\n                                + STORAGE_TMP_SUFFIX);\n        try (FSDataOutputStream out = fs.create(tmpFilePath, false)) {\n            out.write(datas);","sourceCodeStart":73,"sourceCodeEnd":109,"githubUrl":"https://github.com/apache/seatunnel/blob/cf67b549a7a6c35fa0beb12d83c62892427ea919/seatunnel-engine/seatunnel-engine-storage/checkpoint-storage-plugins/checkpoint-storage-hdfs/src/main/java/org/apache/seatunnel/engine/checkpoint/storage/hdfs/HdfsStorage.java#L73-L109","documentation":"HdfsStorage.storeCheckPoint serializes the PipelineState to bytes before writing to HDFS. If serialization throws an IOException, the method wraps it in a CheckpointStorageException whose message includes the failing state, pinpointing corrupt or unserializable checkpoint contents rather than a storage problem.","triggerScenarios":"storeCheckPoint(state) (also reached via modifyResumeTokenInCheckpoint) when PipelineState contains objects that fail Java serialization — e.g. states referencing classes not present on the classpath (ClassNotFoundException during serialization wrapped in IOException) or a corrupted in-memory state object.","commonSituations":"Version mismatch: checkpoints written/read across different SeaTunnel versions where a state class changed or was removed, connector plugin jars missing from the classpath, or mixing engine versions in a rolling upgrade.","solutions":["Ensure all connector and engine jars are identical versions across the cluster","Check the nested IOException cause for ClassNotFoundException / NotSerializableException and add the missing jar or make the class serializable","Do not attempt to resume checkpoints written by an incompatible SeaTunnel version; use a fresh savepoint","Enable debug logging to inspect which field of PipelineState fails to serialize"],"exampleFix":null,"handlingStrategy":"try-catch","validationCode":null,"typeGuard":null,"tryCatchPattern":"try {\n  storage.storeCheckPoint(state);\n} catch (CheckpointStorageException e) {\n  if (e.getMessage().startsWith(\"Failed to serialize checkpoint data\")) {\n    Throwable cause = e.getCause();\n    if (cause instanceof IOException && cause.getCause() instanceof ClassNotFoundException) {\n      log.error(\"Missing class in checkpoint state; align jar versions across cluster\");\n    }\n  } else throw e;\n}","preventionTips":["Keep SeaTunnel engine and all plugin jars at identical versions cluster-wide","Never resume checkpoints written by a different SeaTunnel major/minor version","Only put Serializable types into state that crosses checkpoint boundaries","Watch the cause chain: ClassNotFoundException/NotSerializableException points to the exact fix"],"tags":["serialization","checkpoint-storage","hdfs"],"backgroundTag":"json-marshal-failed","analyzedSha":"cf67b549a7a6c35fa0beb12d83c62892427ea919","analyzedAt":"2026-09-10T21:44:55.265Z","contentChangedAt":"2026-09-10T21:44:55.265Z","schemaVersion":2},"datasetVersion":"2026-09-14T11:17:12.474Z"}