better debugging when unable to insert VSE

I saw this error once:

Apr 27 21:01:33 nuc moonfire-nvr[188570]: s-reolink-sub
moonfire_nvr::streamer] reolink-sub: sleeping for Duration { secs: 1,
nanos: 0 } after error: CHECK constraint failed: video_sample_entry

and would like to understand it better.

server/Cargo.lock

@@ -1192,6 +1192,7 @@ dependencies = [
  "nix",
  "odds",
  "parking_lot",
+ "pretty-hex",
  "prettydiff",
  "protobuf",
  "protobuf-codegen-pure",
@@ -1550,6 +1551,12 @@ version = "0.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac74c624d6b2d21f425f752262f42188365d7b8ff1aff74c82e45136510a4857"
 
+[[package]]
+name = "pretty-hex"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc5c99d529f0d30937f6f4b8a86d988047327bb88d04d2c4afc356de74722131"
+
 [[package]]
 name = "prettydiff"
 version = "0.4.0"

server/db/Cargo.toml

@@ -30,6 +30,7 @@ mylog = { git = "https://github.com/scottlamb/mylog" }
 nix = "0.19.0"
 odds = { version = "0.4.0", features = ["std-vec"] }
 parking_lot = { version = "0.11.1", features = [] }
+pretty-hex = "0.2.1"
 prettydiff = "0.4.0"
 protobuf = { git = "https://github.com/stepancheg/rust-protobuf" }
 ring = "0.16.2"

server/db/db.rs

@@ -135,7 +135,7 @@ pub struct VideoSampleEntry {
     pub pasp_v_spacing: u16,
 }
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(PartialEq, Eq)]
 pub struct VideoSampleEntryToInsert {
     pub data: Vec<u8>,
     pub rfc6381_codec: String,
@@ -145,6 +145,20 @@ pub struct VideoSampleEntryToInsert {
     pub pasp_v_spacing: u16,
 }
 
+impl std::fmt::Debug for VideoSampleEntryToInsert {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        use pretty_hex::PrettyHex;
+        f.debug_struct("VideoSampleEntryToInsert")
+            .field("data", &self.data.hex_dump())
+            .field("rfc6381_codec", &self.rfc6381_codec)
+            .field("width", &self.width)
+            .field("height", &self.height)
+            .field("pasp_h_spacing", &self.pasp_h_spacing)
+            .field("pasp_v_spacing", &self.pasp_v_spacing)
+            .finish()
+    }
+}
+
 /// A row used in `list_recordings_by_time` and `list_recordings_by_id`.
 #[derive(Copy, Clone, Debug)]
 pub struct ListRecordingsRow {
@@ -1708,7 +1722,8 @@ impl LockedDatabase {
             ":pasp_v_spacing": i32::from(entry.pasp_v_spacing),
             ":rfc6381_codec": &entry.rfc6381_codec,
             ":data": &entry.data,
-        })?;
+        })
+        .map_err(|e| Error::from(e).context(format!("Unable to insert {:#?}", &entry)))?;
 
         let id = self.conn.last_insert_rowid() as i32;
         self.video_sample_entries_by_id.insert(