Files
lancedb/docs/web-tests/rs/quickstart.rs
T
Brendan Clement 215f78de96 docs: read the Quickstart image from where the examples now live
The TypeScript and Rust Quickstarts read the image from ../../docs/static,
the layout before the documentation moved into this repository. The file is
docs/web/static/assets/images/quickstart/sir-lancelot.jpg, so the TypeScript
test failed with ENOENT and the Rust example panicked at the read. Both now
resolve the image from the example's own directory (__dirname and
CARGO_MANIFEST_DIR), and the two Quickstart exports are regenerated with
docs/web-tests/mdx_snippets_gen.py.
2026-10-05 20:27:11 -07:00

348 lines
11 KiB
Rust

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright The LanceDB Authors
use std::sync::Arc;
use arrow_array::types::Float32Type;
use arrow_array::{
FixedSizeListArray, Int8Array, LargeStringArray, RecordBatch, RecordBatchIterator, StructArray,
};
use arrow_schema::{DataType, Field, FieldRef, Schema};
use lancedb::arrow::IntoPolars;
use lancedb::database::CreateTableMode;
use lancedb::query::{ExecutableQuery, QueryBase, Select};
use lancedb::{connect, table::NewColumnTransform};
use polars::prelude::DataFrame;
use serde::{Deserialize, Serialize};
// --8<-- [start:quickstart_define_struct]
// Define structs representing the data schema
#[derive(Debug, Clone, Serialize, Deserialize)]
struct Stats {
strength: i8,
magic: i8,
leadership: i8,
wisdom: i8,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
struct Character {
id: String,
name: String,
role: String,
description: String,
stats: Stats,
vector: [f32; 4],
}
fn characters_schema() -> Arc<Schema> {
Arc::new(Schema::new(vec![
Field::new("id", DataType::LargeUtf8, false),
Field::new("name", DataType::LargeUtf8, false),
Field::new("role", DataType::LargeUtf8, false),
Field::new("description", DataType::LargeUtf8, false),
Field::new(
"stats",
DataType::Struct(arrow_schema::Fields::from(vec![
Arc::new(Field::new("strength", DataType::Int8, false)),
Arc::new(Field::new("magic", DataType::Int8, false)),
Arc::new(Field::new("leadership", DataType::Int8, false)),
Arc::new(Field::new("wisdom", DataType::Int8, false)),
])),
false,
),
Field::new(
"vector",
DataType::FixedSizeList(Arc::new(Field::new("item", DataType::Float32, true)), 4),
false,
),
]))
}
// --8<-- [end:quickstart_define_struct]
type BatchIter = Box<dyn arrow_array::RecordBatchReader + Send>;
fn characters_to_reader(schema: Arc<Schema>, rows: &[Character]) -> BatchIter {
let ids = LargeStringArray::from_iter_values(rows.iter().map(|row| row.id.as_str()));
let names = LargeStringArray::from_iter_values(rows.iter().map(|row| row.name.as_str()));
let roles = LargeStringArray::from_iter_values(rows.iter().map(|row| row.role.as_str()));
let descriptions =
LargeStringArray::from_iter_values(rows.iter().map(|row| row.description.as_str()));
let strength = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.strength));
let magic = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.magic));
let leadership = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.leadership));
let wisdom = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.wisdom));
let stats_fields: Vec<FieldRef> = vec![
Arc::new(Field::new("strength", DataType::Int8, false)),
Arc::new(Field::new("magic", DataType::Int8, false)),
Arc::new(Field::new("leadership", DataType::Int8, false)),
Arc::new(Field::new("wisdom", DataType::Int8, false)),
];
let stats = StructArray::new(
stats_fields.into(),
vec![
Arc::new(strength),
Arc::new(magic),
Arc::new(leadership),
Arc::new(wisdom),
],
None,
);
let vectors = FixedSizeListArray::from_iter_primitive::<Float32Type, _, _>(
rows.iter()
.map(|row| Some(row.vector.iter().copied().map(Some).collect::<Vec<_>>())),
4,
);
let batch = RecordBatch::try_new(
schema.clone(),
vec![
Arc::new(ids),
Arc::new(names),
Arc::new(roles),
Arc::new(descriptions),
Arc::new(stats),
Arc::new(vectors),
],
)
.unwrap();
Box::new(RecordBatchIterator::new(
vec![Ok(batch)].into_iter(),
schema,
))
}
#[tokio::main]
async fn main() {
let temp_dir = tempfile::tempdir().unwrap();
let uri = temp_dir.path().to_str().unwrap();
let db = connect(uri).execute().await.unwrap();
// --8<-- [start:quickstart_data]
let data = vec![
Character {
id: "1".to_string(),
name: "King Arthur".to_string(),
role: "King".to_string(),
description: "Leader of Camelot and wielder of Excalibur.".to_string(),
stats: Stats {
strength: 4,
magic: 1,
leadership: 5,
wisdom: 4,
},
vector: [0.7, 0.1, 0.9, 0.7],
},
Character {
id: "2".to_string(),
name: "Merlin".to_string(),
role: "Wizard".to_string(),
description: "Advisor and prophet with deep magical knowledge.".to_string(),
stats: Stats {
strength: 2,
magic: 5,
leadership: 4,
wisdom: 5,
},
vector: [0.2, 0.9, 0.4, 0.9],
},
Character {
id: "3".to_string(),
name: "Sir Lancelot".to_string(),
role: "Knight".to_string(),
description: "Legendary knight known for courage and combat skill.".to_string(),
stats: Stats {
strength: 5,
magic: 1,
leadership: 3,
wisdom: 3,
},
vector: [0.9, 0.1, 0.5, 0.4],
},
];
// --8<-- [end:quickstart_data]
// --8<-- [start:quickstart_create_table]
let schema = characters_schema();
let table = db
.create_table("characters", characters_to_reader(schema.clone(), &data))
.mode(CreateTableMode::Overwrite)
.execute()
.await
.unwrap();
// --8<-- [end:quickstart_create_table]
assert_eq!(table.count_rows(None).await.unwrap(), 3);
db.drop_table("characters", &[]).await.unwrap();
// --8<-- [start:quickstart_create_table_no_overwrite]
let table = db
.create_table("characters", characters_to_reader(schema.clone(), &data))
.execute()
.await
.unwrap();
// --8<-- [end:quickstart_create_table_no_overwrite]
assert_eq!(table.count_rows(None).await.unwrap(), 3);
// --8<-- [start:quickstart_vector_search_1]
// Search for examples similar to a "wise magical advisor"
let query_vector = [0.2, 0.8, 0.4, 0.9];
let result: DataFrame = table
.query()
.nearest_to(&query_vector)
.unwrap()
.select(Select::Columns(vec![
"name".to_string(),
"role".to_string(),
"description".to_string(),
"_distance".to_string(),
]))
.limit(2)
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{result:?}");
// --8<-- [end:quickstart_vector_search_1]
let name_col = result.column("name").unwrap().str().unwrap();
assert_eq!(name_col.get(0).unwrap(), "Merlin");
// --8<-- [start:quickstart_curate_with_metadata]
let curated: DataFrame = table
.query()
.nearest_to(&query_vector)
.unwrap()
.only_if("stats.magic >= 4")
.select(Select::Columns(vec![
"name".to_string(),
"role".to_string(),
"description".to_string(),
"_distance".to_string(),
]))
.limit(2)
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{curated:?}");
// --8<-- [end:quickstart_curate_with_metadata]
let curated_name_col = curated.column("name").unwrap().str().unwrap();
assert_eq!(curated_name_col.get(0).unwrap(), "Merlin");
// --8<-- [start:quickstart_output_array]
let result: DataFrame = table
.query()
.nearest_to(&query_vector)
.unwrap()
.select(Select::Columns(vec![
"name".to_string(),
"role".to_string(),
"description".to_string(),
"_distance".to_string(),
]))
.limit(2)
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{result:?}");
// --8<-- [end:quickstart_output_array]
let name_col = result.column("name").unwrap().str().unwrap();
assert_eq!(name_col.get(0).unwrap(), "Merlin");
// --8<-- [start:quickstart_add_feature]
table
.add_columns(
NewColumnTransform::SqlExpressions(vec![(
"power_score".to_string(),
"cast(((stats.strength + stats.magic + stats.leadership + stats.wisdom) / 4.0) as float)"
.to_string(),
)]),
None,
)
.await
.unwrap();
// --8<-- [end:quickstart_add_feature]
// --8<-- [start:quickstart_query_feature]
let features: DataFrame = table
.query()
.select(Select::Columns(vec![
"name".to_string(),
"role".to_string(),
"power_score".to_string(),
]))
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{features:?}");
// --8<-- [end:quickstart_query_feature]
assert!(features.column("power_score").is_ok());
// --8<-- [start:quickstart_multimodal_bytes]
use std::sync::Arc;
use arrow_array::{
BinaryArray, FixedSizeListArray, LargeStringArray, RecordBatch, RecordBatchIterator,
};
use arrow_schema::{DataType, Field, Schema};
let image_path = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
.join("../../web/static/assets/images/quickstart/sir-lancelot.jpg");
let image_bytes = std::fs::read(image_path).unwrap();
let image_schema = Arc::new(Schema::new(vec![
Field::new("id", DataType::LargeUtf8, false),
Field::new("description", DataType::LargeUtf8, false),
Field::new("image", DataType::Binary, false),
Field::new(
"vector",
DataType::FixedSizeList(Arc::new(Field::new("item", DataType::Float32, true)), 4),
false,
),
]));
let image_vectors = [[0.9_f32, 0.1, 0.5, 0.4]];
let image_batch = RecordBatch::try_new(
image_schema.clone(),
vec![
Arc::new(LargeStringArray::from_iter_values(["lancelot"])),
Arc::new(LargeStringArray::from_iter_values([
"Portrait of Sir Lancelot",
])),
Arc::new(BinaryArray::from_iter_values([image_bytes.as_slice()])),
Arc::new(
FixedSizeListArray::from_iter_primitive::<Float32Type, _, _>(
image_vectors
.iter()
.map(|vector| Some(vector.iter().copied().map(Some).collect::<Vec<_>>())),
4,
),
),
],
)
.unwrap();
let image_reader: Box<dyn arrow_array::RecordBatchReader + Send> = Box::new(
RecordBatchIterator::new(vec![Ok(image_batch)].into_iter(), image_schema),
);
let multimodal_table = db
.create_table("character_images", image_reader)
.mode(CreateTableMode::Overwrite)
.execute()
.await
.unwrap();
// --8<-- [end:quickstart_multimodal_bytes]
assert_eq!(multimodal_table.count_rows(None).await.unwrap(), 1);
}