Add verify option to insert example (#321)

firewood/examples/insert.rs

@@ -5,11 +5,11 @@
 // insert some random keys using the front-end API.
 
 use clap::Parser;
-use std::{error::Error, ops::RangeInclusive, sync::Arc, time::Instant};
+use std::{collections::HashMap, error::Error, ops::RangeInclusive, sync::Arc, time::Instant};
 
 use firewood::{
     db::{Batch, BatchOp, Db, DbConfig},
-    v2::api::{Db as DbApi, Proposal},
+    v2::api::{Db as DbApi, DbView, Proposal},
 };
 use rand::{distributions::Alphanumeric, Rng};
 
@@ -23,6 +23,8 @@ struct Args {
     batch_keys: usize,
     #[arg(short, long, default_value_t = 100)]
     inserts: usize,
+    #[arg(short, long, default_value_t = 0, value_parser = clap::value_parser!(u16).range(0..=100))]
+    read_verify_percent: u16,
 }
 
 fn string_to_range(input: &str) -> Result<RangeInclusive<usize>, Box<dyn Error + Sync + Send>> {
@@ -69,12 +71,51 @@ async fn main() -> Result<(), Box<dyn Error>> {
             })
             .map(|(key, value)| BatchOp::Put { key, value })
             .collect();
+
+        let verify = get_keys_to_verify(&batch, args.read_verify_percent);
+
         let proposal: Arc<firewood::db::Proposal> = db.propose(batch).await.unwrap().into();
         proposal.commit().await?;
+        verify_keys(&db, verify).await?;
     }
 
     let duration = start.elapsed();
-    println!("Generated and inserted {keys} in {duration:?}");
+    println!(
+        "Generated and inserted {} batches of size {keys} in {duration:?}",
+        args.inserts
+    );
+
+    Ok(())
+}
 
+fn get_keys_to_verify(batch: &Batch<Vec<u8>, Vec<u8>>, pct: u16) -> HashMap<Vec<u8>, Vec<u8>> {
+    if pct == 0 {
+        HashMap::new()
+    } else {
+        batch
+            .iter()
+            .filter(|_last_key| rand::thread_rng().gen_range(0..=(100 - pct)) == 0)
+            .map(|op| {
+                if let BatchOp::Put { key, value } = op {
+                    (key.clone(), value.clone())
+                } else {
+                    unreachable!()
+                }
+            })
+            .collect()
+    }
+}
+
+async fn verify_keys(
+    db: &Db,
+    verify: HashMap<Vec<u8>, Vec<u8>>,
+) -> Result<(), firewood::v2::api::Error> {
+    if !verify.is_empty() {
+        let hash = db.root_hash().await?;
+        let revision = db.revision(hash).await?;
+        for (key, value) in verify {
+            assert_eq!(*value, revision.val(key).await?.unwrap());
+        }
+    }
     Ok(())
 }