query-http-csv.rs

// Licensed to the Apache Software Foundation (ASF) under one
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// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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use datafusion::error::Result;
use datafusion::prelude::*;
use object_store::http::HttpBuilder;
use std::sync::Arc;
use url::Url;

/// This example demonstrates executing a simple query against an Arrow data source (CSV) and
/// fetching results
#[tokio::main]
async fn main() -> Result<()> {
    // create local execution context
    let ctx = SessionContext::new();

    // setup http object store
    let base_url = Url::parse("https://github.com").unwrap();
    let http_store = HttpBuilder::new()
        .with_url(base_url.clone())
        .build()
        .unwrap();
    ctx.register_object_store(&base_url, Arc::new(http_store));

    // register csv file with the execution context
    ctx.register_csv(
        "aggregate_test_100",
        "https://github.com/apache/arrow-testing/raw/master/data/csv/aggregate_test_100.csv",
        CsvReadOptions::new(),
    )
    .await?;

    // execute the query
    let df = ctx
        .sql("SELECT c1,c2,c3 FROM aggregate_test_100 LIMIT 5")
        .await?;

    // print the results
    df.show().await?;

    Ok(())
}