Moved QLDB code examples into qldb directory; added create-ledger code example (#485)

[package]

name = "qldb-helloworld"

version = "0.1.0"

authors = ["Russell Cohen <rcoh@amazon.com>"]

edition = "2018"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]

qldb = { package = "aws-sdk-qldb", path = "../../build/aws-sdk/qldb" }

### To use native TLS:

# dynamodb = { package = "aws-sdk-qldb", path = "../../build/aws-sdk/qldb", default-features = false, features = ["native-tls"] }

tokio = { version = "1", features = ["full"] }

# used only for static endpoint configuration:

http = "0.2.3"

# used only to enable basic logging:

env_logger = "0.8.2"

# Qldb List Ledgers World Example

This example show how to use the SDK to list existing ledgers.

/*

 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.

 * SPDX-License-Identifier: Apache-2.0.

 */

#[tokio::main]

async fn main() -> Result<(), qldb::Error> {

    let client = qldb::Client::from_env();

    let result = client.list_ledgers().send().await?;

    if let Some(ledgers) = result.ledgers {

        for ledger in ledgers {

            println!("* {:?}", ledger);

        }

        if result.next_token.is_some() {

            todo!("pagination is not yet demonstrated")

        }

    }

    Ok(())

}

[package]

name = "qldbsession-helloworld"

name = "qldb-code-examples"

version = "0.1.0"

authors = ["Russell Cohen <rcoh@amazon.com>"]

authors = ["Russell Cohen <rcoh@amazon.com>", "Doug Schwartz <dougsch@amazon.com>"]

edition = "2018"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]

qldb = { package = "aws-sdk-qldb", path = "../../build/aws-sdk/qldb" }

qldbsession = { package = "aws-sdk-qldbsession", path = "../../build/aws-sdk/qldbsession" }

### To use native TLS:

# qldbsession = { package = "aws-sdk-qldbsession", path = "../../build/aws-sdk/qldbsession", default-features = false, features = ["native-tls"] }

aws-types = { path = "../../build/aws-sdk/aws-types" }

tokio = { version = "1", features = ["full"] }

# For command-line arguments

structopt = { version = "0.3", default-features = false }

tracing-subscriber = { version = "0.2.16", features = ["fmt"] }

# used only for static endpoint configuration:

http = "0.2.3"

# AWS SDK for Rust code examples for Amazon QLDB

Amazon Quantum Ledger Database (Amazon QLDB) is a fully managed ledger database that provides a transparent, immutable, and cryptographically verifiable transaction log owned by a central trusted authority.

## create-ledger

This code example creates an Amazon QLDB ledger.

### Usage

```cargo run --bin create-ledger -l LEDGER [-r REGION] [-v]```

where:

- _LEDGER_ is the name of the ledger to create.

- _REGION_ is the region in which the client is created.

  If not supplied, uses the value of the **AWS_DEFAULT_REGION** environment variable.

  If the environment variable is not set, defaults to **us-west-2**.

- __-v__ enables displaying additional information.

## list-ledgers

This code example lists your Amazon QLDB ledgers.

### Usage

```cargo run --bin list-ledgers [-r REGION] [-v]```

where:

- _REGION_ is the region in which the client is created.

  If not supplied, uses the value of the **AWS_DEFAULT_REGION** environment variable.

  If the environment variable is not set, defaults to **us-west-2**.

- __-v__ enables displaying additional information.

## qldb-helloworld

This code example creates a low-level Amazon QLDB session against a ledger.

The QldbSession API is not intended to be used directly. Instead, we recommend using a higher-level driver, such as the Amazon QLDB Driver for Rust.

### Usage

cargo run --bin qldb-helloworld -l LEDGER [-r REGION] [-v]

where:

- _LEDGER_ is the name of the ledger to create the session against.

- _REGION_ is the region in which the client is created.

  If not supplied, uses the value of the **AWS_DEFAULT_REGION** environment variable.

  If the environment variable is not set, defaults to **us-west-2**.

- __-v__ enables displaying additional information.

##