ut: add test for Snapshot (#39)

crates/paimon/Cargo.toml

@@ -30,8 +30,9 @@ version.workspace = true
 bitflags = "2.6.0"
 chrono = { version = "0.4.38", features = ["serde"] }
 serde = { version = "1", features = ["derive"] }
-serde_with = "3.8.3"
 serde_bytes = "0.11.15"
+serde_json = "1.0.120"
+serde_with = "3.8.3"
 snafu = "0.8.3"
 typed-builder = "^0.19"
 opendal = "0.48"

crates/paimon/src/spec/snapshot.rs

@@ -16,6 +16,7 @@
 // under the License.
 
 use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
 use typed_builder::TypedBuilder;
 
 /// Snapshot for paimon.
@@ -38,7 +39,21 @@ pub struct Snapshot {
     /// a manifest recording all index files of this table
     #[builder(default = None)]
     index_manifest: Option<String>,
+    /// user who committed this snapshot
     commit_user: String,
+    /// Mainly for snapshot deduplication.
+    ///
+    /// If multiple snapshots have the same commitIdentifier, reading from any of these snapshots
+    /// must produce the same table.
+    ///
+    /// If snapshot A has a smaller commitIdentifier than snapshot B, then snapshot A must be
+    /// committed before snapshot B, and thus snapshot A must contain older records than snapshot B.
+    commit_identifier: i64,
+    /// timestamp of this snapshot
+    time_millis: u64,
+    /// log offsets of all changes occurred in this snapshot
+    #[builder(default = None)]
+    log_offsets: Option<HashMap<i32, i64>>,
     /// record count of all changes occurred in this snapshot
     #[builder(default = None)]
     total_record_count: Option<i64>,
@@ -105,6 +120,24 @@ impl Snapshot {
         &self.commit_user
     }
 
+    /// Get the commit time of this snapshot.
+    #[inline]
+    pub fn time_millis(&self) -> u64 {
+        self.time_millis
+    }
+
+    /// Get the commit identifier of this snapshot.
+    #[inline]
+    pub fn commit_identifier(&self) -> i64 {
+        self.commit_identifier
+    }
+
+    /// Get the log offsets of this snapshot.
+    #[inline]
+    pub fn log_offsets(&self) -> Option<&HashMap<i32, i64>> {
+        self.log_offsets.as_ref()
+    }
+
     /// Get the total record count of this snapshot.
     #[inline]
     pub fn total_record_count(&self) -> Option<i64> {
@@ -135,3 +168,217 @@ impl Snapshot {
         self.statistics.as_deref()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json;
+
+    #[test]
+    fn test_snapshot_creation() {
+        let snapshot = Snapshot::builder()
+            .version(3)
+            .id(1)
+            .schema_id(0)
+            .base_manifest_list("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0".to_string())
+            .delta_manifest_list("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1".to_string())
+            .commit_user("cf568e07-05ad-4943-b4bd-37461bc58729".to_string())
+            .commit_identifier(9223372036854775807)
+            .time_millis(1721287833568)
+            .build();
+
+        assert_eq!(snapshot.version(), 3);
+        assert_eq!(snapshot.id(), 1);
+        assert_eq!(snapshot.schema_id(), 0);
+        assert_eq!(
+            snapshot.base_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0"
+        );
+        assert_eq!(
+            snapshot.delta_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1"
+        );
+        assert_eq!(
+            snapshot.commit_user(),
+            "cf568e07-05ad-4943-b4bd-37461bc58729"
+        );
+        assert_eq!(snapshot.commit_identifier(), 9223372036854775807);
+        assert_eq!(snapshot.time_millis(), 1721287833568);
+        assert!(snapshot.changelog_manifest_list().is_none());
+        assert!(snapshot.index_manifest().is_none());
+        assert!(snapshot.log_offsets().is_none());
+        assert!(snapshot.total_record_count().is_none());
+        assert!(snapshot.delta_record_count().is_none());
+        assert!(snapshot.changelog_record_count().is_none());
+        assert!(snapshot.watermark().is_none());
+        assert!(snapshot.statistics().is_none());
+    }
+
+    #[test]
+    fn test_snapshot_with_optional_fields() {
+        let snapshot = Snapshot::builder()
+            .version(3)
+            .id(1)
+            .schema_id(0)
+            .base_manifest_list("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0".to_string())
+            .delta_manifest_list("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1".to_string())
+            .changelog_manifest_list(Some(
+                "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-2".to_string(),
+            ))
+            .index_manifest(Some(
+                "index-manifest-55e3e815-08ab-4a70-a808-a8df5d275cb4-0".to_string(),
+            ))
+            .commit_user("cf568e07-05ad-4943-b4bd-37461bc58729".to_string())
+            .commit_identifier(9223372036854775807)
+            .time_millis(1721287833568)
+            .total_record_count(Some(1))
+            .delta_record_count(Some(1))
+            .changelog_record_count(Some(0))
+            .watermark(Some(-9223372036854775808))
+            .statistics(Some("statistics_v2".to_string()))
+            .build();
+
+        assert_eq!(snapshot.version(), 3);
+        assert_eq!(snapshot.id(), 1);
+        assert_eq!(snapshot.schema_id(), 0);
+        assert_eq!(
+            snapshot.base_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0"
+        );
+        assert_eq!(
+            snapshot.delta_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1"
+        );
+        assert_eq!(
+            snapshot.changelog_manifest_list(),
+            Some("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-2")
+        );
+        assert_eq!(
+            snapshot.index_manifest(),
+            Some("index-manifest-55e3e815-08ab-4a70-a808-a8df5d275cb4-0")
+        );
+        assert_eq!(
+            snapshot.commit_user(),
+            "cf568e07-05ad-4943-b4bd-37461bc58729"
+        );
+        assert_eq!(snapshot.commit_identifier(), 9223372036854775807);
+        assert_eq!(snapshot.time_millis(), 1721287833568);
+        assert_eq!(
+            snapshot.changelog_manifest_list(),
+            Some("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-2")
+        );
+        assert_eq!(snapshot.total_record_count(), Some(1));
+        assert_eq!(snapshot.delta_record_count(), Some(1));
+        assert_eq!(snapshot.changelog_record_count(), Some(0));
+        assert_eq!(snapshot.watermark(), Some(-9223372036854775808));
+        assert_eq!(snapshot.statistics(), Some("statistics_v2"));
+    }
+
+    #[test]
+    fn test_snapshot_with_none_fields() {
+        let snapshot = Snapshot::builder()
+            .version(3)
+            .id(1)
+            .schema_id(0)
+            .base_manifest_list("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0".to_string())
+            .delta_manifest_list("manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1".to_string())
+            .changelog_manifest_list(None)
+            .index_manifest(None)
+            .commit_user("cf568e07-05ad-4943-b4bd-37461bc58729".to_string())
+            .commit_identifier(9223372036854775807)
+            .time_millis(1721287833568)
+            .total_record_count(None)
+            .delta_record_count(None)
+            .changelog_record_count(None)
+            .watermark(None)
+            .statistics(None)
+            .build();
+
+        assert_eq!(snapshot.version(), 3);
+        assert_eq!(snapshot.id(), 1);
+        assert_eq!(snapshot.schema_id(), 0);
+        assert_eq!(
+            snapshot.base_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0"
+        );
+        assert_eq!(
+            snapshot.delta_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1"
+        );
+        assert_eq!(
+            snapshot.commit_user(),
+            "cf568e07-05ad-4943-b4bd-37461bc58729"
+        );
+        assert_eq!(snapshot.commit_identifier(), 9223372036854775807);
+        assert_eq!(snapshot.time_millis(), 1721287833568);
+        assert!(snapshot.changelog_manifest_list().is_none());
+        assert!(snapshot.index_manifest().is_none());
+        assert!(snapshot.log_offsets().is_none());
+        assert!(snapshot.total_record_count().is_none());
+        assert!(snapshot.delta_record_count().is_none());
+        assert!(snapshot.changelog_record_count().is_none());
+        assert!(snapshot.watermark().is_none());
+        assert!(snapshot.statistics().is_none());
+    }
+
+    #[test]
+    fn test_snapshot_serialization_deserialization() {
+        let data = r#"
+    {
+      "version" : 3,
+      "id" : 1,
+      "schemaId" : 0,
+      "baseManifestList" : "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0",
+      "deltaManifestList" : "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1",
+      "changelogManifestList" : null,
+      "indexManifest" : "index-manifest-55e3e815-08ab-4a70-a808-a8df5d275cb4-0",
+      "commitUser" : "cf568e07-05ad-4943-b4bd-37461bc58729",
+      "commitIdentifier" : 9223372036854775807,
+      "timeMillis" : 1721287833568,
+      "logOffsets" : { },
+      "totalRecordCount" : 1,
+      "deltaRecordCount" : 1,
+      "changelogRecordCount" : 0,
+      "watermark" : -9223372036854775808
+    }
+    "#;
+
+        let snapshot: Snapshot =
+            serde_json::from_str(data).expect("Failed to deserialize Snapshot");
+
+        assert_eq!(snapshot.version(), 3);
+        assert_eq!(snapshot.id(), 1);
+        assert_eq!(snapshot.schema_id(), 0);
+        assert_eq!(
+            snapshot.base_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-0"
+        );
+        assert_eq!(
+            snapshot.delta_manifest_list(),
+            "manifest-list-4091b92b-01d3-4b91-8e47-8c9f61847d2f-1"
+        );
+        assert_eq!(snapshot.changelog_manifest_list(), None);
+        assert_eq!(
+            snapshot.index_manifest(),
+            Some("index-manifest-55e3e815-08ab-4a70-a808-a8df5d275cb4-0")
+        );
+        assert_eq!(
+            snapshot.commit_user(),
+            "cf568e07-05ad-4943-b4bd-37461bc58729"
+        );
+        assert_eq!(snapshot.commit_identifier(), 9223372036854775807);
+        assert_eq!(snapshot.time_millis(), 1721287833568);
+        assert!(snapshot.changelog_manifest_list().is_none());
+        assert_eq!(snapshot.total_record_count(), Some(1));
+        assert_eq!(snapshot.delta_record_count(), Some(1));
+        assert_eq!(snapshot.changelog_record_count(), Some(0));
+        assert_eq!(snapshot.watermark(), Some(-9223372036854775808));
+
+        let serialized = serde_json::to_string(&snapshot).expect("Failed to serialize Snapshot");
+
+        let deserialized: Snapshot =
+            serde_json::from_str(&serialized).expect("Failed to deserialize serialized Snapshot");
+
+        assert_eq!(snapshot, deserialized);
+    }
+}