TypeDB Rust Driver

Driver Architecture

To learn about the mechanism that TypeDB drivers use set up communication with databases running on the TypeDB Server, refer to the Drivers Overview.

The TypeDB Rust Driver provides a fully async API that supports multiple async runtimes or a synchronous interface gated by the sync feature.

API Reference

To learn about the methods available for executing queries and retrieving their answers using Rust, refer to the API Reference.

Install TypeDB Rust Driver through Cargo

1. Import typedb-driver through Cargo:

cargo add typedb-driver

2. Make sure the TypeDB Server is running.
3. Use TypeDB Driver in your program (see Example usage or tests/integration for examples):

use typedb_driver::TypeDBDriver;

let driver = TypeDBDriver::new_core(TypeDBDriver::DEFAULT_ADDRESS).await.unwrap();

Build from Source

Note: You don't need to compile TypeDB Driver from source if you just want to use it in your code. See the " Quickstart" section above.

1. Make sure you have Bazel installed on your machine.

2. Build the library:

   a) to build the native/raw rlib:

   bazel build //rust:typedb_driver
   

   The rlib will be produced at: bazel-bin/libtypedb_driver-{hash}.rlib.

   b) to build the crate for a Cargo project:

   bazel build //rust:assemble_crate
   

   The Cargo crate will be produced at:

   bazel-bin/assemble_crate.crate
   

   You can then unzip this crate to retrieve Cargo.toml. Please note: this process has not yet been thoroughly tested. The generated Cargo.toml may not be fully correct. See the Cargo.toml of the typedb-driver crate for reference.

Example usage

TypeDB Core

use futures::{StreamExt, TryStreamExt};
use typedb_driver::{
    answer::{
        concept_document::{Leaf, Node},
        ConceptRow, QueryAnswer,
    },
    concept::{Concept, ValueType},
    Error, TransactionType, TypeDBDriver,
};

fn typedb_example() {
    async_std::task::block_on(async {
        // Open a driver connection
        let driver = TypeDBDriver::new_core(TypeDBDriver::DEFAULT_ADDRESS).await.unwrap();

        // Create a database
        driver.databases().create("typedb").await.unwrap();
        let database = driver.databases().get("typedb").await.unwrap();

        // Dropped transactions are closed
        {
            // Open transactions of 3 types
            let transaction = driver.transaction(database.name(), TransactionType::Read).await.unwrap();

            // Execute any TypeDB query using TypeQL. Wrong queries are rejected with an explicit error
            let result = transaction.query("define entity i-cannot-be-defined-in-read-transactions;").await;
            match result {
                Ok(_) => println!("This line will not be printed"),
                // Handle errors
                Err(error) => match error {
                    Error::Connection(connection) => println!("Could not connect: {connection}"),
                    Error::Server(server) => {
                        println!("Received a detailed server error regarding the executed query: {server}")
                    }
                    Error::Internal(_) => panic!("Unexpected internal error"),
                    _ => println!("Received an unexpected external error: {error}"),
                },
            }
        }

        // Open a schema transaction to make schema changes
        let transaction = driver.transaction(database.name(), TransactionType::Schema).await.unwrap();
        let define_query = r#"
        define
          entity person, owns name, owns age;
          attribute name, value string;
          attribute age, value long;
        "#;
        let answer = transaction.query(define_query).await.unwrap();

        // Work with the driver's enums in a classic way or using helper methods
        if answer.is_ok() && matches!(answer, QueryAnswer::Ok(_)) {
            println!("OK results do not give any extra interesting information, but they mean that the query is successfully executed!");
        }

        // Commit automatically closes the transaction (don't forget to await the result!)
        transaction.commit().await.unwrap();

        // Open a read transaction to safely read anything without database modifications
        let transaction = driver.transaction(database.name(), TransactionType::Read).await.unwrap();
        let answer = transaction.query("match entity $x;").await.unwrap();

        // Collect concept rows that represent the answer as a table
        let rows: Vec<ConceptRow> = answer.into_rows().try_collect().await.unwrap();
        let row = rows.get(0).unwrap();

        // Retrieve column names to get concepts by index if the variable names are lost
        let column_names = row.get_column_names();

        let column_name = column_names.get(0).unwrap();

        // Get concept by the variable name (column name)
        let concept_by_name = row.get(column_name).unwrap();

        // Get concept by the header's index
        let concept_by_index = row.get_index(0).unwrap();

        // Check if it's an entity type
        if concept_by_name.is_entity_type() {
            print!("Getting concepts by variable names and indexes is equally correct. ");
            println!(
                "Both represent the defined entity type: '{}' (in case of a doubt: '{}')",
                concept_by_name.get_label(),
                concept_by_index.get_label()
            );
        }

        // Continue querying in the same transaction if needed
        let answer = transaction.query("match attribute $a;").await.unwrap();

        // Concept rows can be used as a stream of results
        let mut rows_stream = answer.into_rows();
        while let Some(Ok(row)) = rows_stream.next().await {
            let mut column_names_iter = row.get_column_names().into_iter();
            let column_name = column_names_iter.next().unwrap();

            let concept_by_name = row.get(column_name).unwrap();

            // Check if it's an attribute type to safely retrieve its value type
            if concept_by_name.is_attribute_type() {
                let label = concept_by_name.get_label();
                let value_type = concept_by_name.get_value_type().unwrap();
                println!("Defined attribute type's label: '{label}', value type: '{value_type}'");
            }

            println!("It is also possible to just print the concept itself: '{}'", concept_by_name);
        }

        // Open a write transaction to insert data
        let transaction = driver.transaction(database.name(), TransactionType::Write).await.unwrap();
        let answer = transaction.query("insert $z isa person, has age 10; $x isa person, has age 20;").await.unwrap();

        // Insert queries also return concept rows
        let mut rows = Vec::new();
        let mut rows_stream = answer.into_rows();
        while let Some(Ok(row)) = rows_stream.next().await {
            rows.push(row);
        }
        let row = rows.get(0).unwrap();

        for column_name in row.get_column_names() {
            let inserted_concept = row.get(column_name).unwrap();
            println!("Successfully inserted ${}: {}", column_name, inserted_concept);
            if inserted_concept.is_entity() {
                println!("This time, it's an entity, not a type!");
            }
        }

        // It is possible to ask for the column names again
        let column_names = row.get_column_names();

        let x = row.get_index(column_names.iter().position(|r| r == "x").unwrap()).unwrap();
        if let Some(iid) = x.get_iid() {
            println!("Each entity receives a unique IID. It can be retrieved directly: {}", iid);
        }

        // Do not forget to commit if the changes should be persisted
        transaction.commit().await.unwrap();

        // Open a read transaction to verify that the inserted data is saved
        let transaction = driver.transaction(database.name(), TransactionType::Read).await.unwrap();

        // A match query can be used for concept row outputs
        let var = "x";
        let answer = transaction.query(format!("match ${} isa person;", var)).await.unwrap();

        // Simple match queries always return concept rows
        let mut count = 0;
        let mut stream = answer.into_rows().map(|result| result.unwrap());
        while let Some(row) = stream.next().await {
            let x = row.get(var).unwrap();
            match x {
                Concept::Entity(x_entity) => {
                    let x_type = x_entity.type_().unwrap();
                    count += 1;
                    println!("Found a person {} of type {}", x, x_type);
                }
                _ => unreachable!("An entity is expected"),
            }
        }
        println!("Total persons found: {}", count);

        // A fetch query can be used for concept document outputs with flexible structure
        let fetch_query = r#"
        match
          $x isa! person, has $a;
          $a isa! $t;
        fetch {
          "single attribute type": $t,
          "single attribute": $a,
          "all attributes": { $x.* },
        };
        "#;
        let answer = transaction.query(fetch_query).await.unwrap();

        // Fetch queries always return concept documents
        let mut count = 0;
        let mut stream = answer.into_documents().map(|result| result.unwrap());
        while let Some(document) = stream.next().await {
            // The content of the document can be explored in details
            match document.root.as_ref().unwrap() {
                Node::Map(map) => {
                    println!("Found a map document:\n{{");
                    for (parameter_name, node) in map {
                        print!("  \"{parameter_name}\": ");
                        match node {
                            Node::Map(map) => println!("map of {} element(s)", map.len()),
                            Node::Leaf(leaf) => match leaf.as_ref().unwrap() {
                                Leaf::Concept(concept) => match concept {
                                    Concept::AttributeType(type_) => println!("attribute type '{}'", type_.label()),
                                    Concept::Attribute(attribute) => println!("attribute '{}'", attribute.value),
                                    _ => unreachable!("Unexpected concept is fetched"),
                                },
                                _ => unreachable!("Unexpected leaf type is fetched"),
                            },
                            _ => unreachable!("Expected lists in inner maps"),
                        }
                        print!("")
                    }
                    println!("}}");
                }
                _ => unreachable!("Unexpected document type is fetched"),
            }

            // The document can be converted to a JSON
            count += 1;
            println!("JSON representation of the fetched document:\n{}", document.into_json().to_string());
        }
        println!("Total documents fetched: {}", count);
        println!("More examples can be found in the API reference and the documentation.\nWelcome to TypeDB!");
    })
}