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Torch Object Storage

Pre-signing mechanism

PreSignedPostSignature（Rust SDK）

The pre_signed_post_signature interface generates the signature and policy required for PostObject. This article explains how to obtain the signature and policy using the Rust SDK's pre_signed_post_signature interface.

Notes

You need to fill in the region and access domain in the sample code based on your actual situation. For details, see Regions and endpoints.

To prevent key leakage, the sample code reads the Access Key ID and Secret Access Key from environment variables. Therefore, before using the SDK, you need to configure long-term access credentials. For details, see Configure long-term access credentials.

Code examples

Using the default expiration time

use async_trait::async_trait;​
use futures_core::future::BoxFuture;​
use std::env;​
use std::future::Future;​
use std::time::Duration;​
use tokio::runtime::Handle;​
use ve_tos_rust_sdk::common::init_tracing_log;​
use ve_tos_rust_sdk::asynchronous::tos;​
use ve_tos_rust_sdk::asynchronous::tos::AsyncRuntime;​
use ve_tos_rust_sdk::auth::{PreSignedPostSignatureInput, SignerAPI};​
use ve_tos_rust_sdk::error::TosError;​
​
#[derive(Debug, Default)]​
pub struct TokioRuntime {}​
​
#[async_trait]​
impl AsyncRuntime for TokioRuntime {​
    type JoinError = tokio::task::JoinError;​
    async fn sleep(&self, duration: Duration) {​
        tokio::time::sleep(duration).await;​
    }​
​
    fn spawn<'a, F>(&self, future: F) -> BoxFuture<'a, Result<F::Output, Self::JoinError>>​
    where​
        F: Future + Send + 'static,​
        F::Output: Send + 'static,​
    {​
        Box::pin(Handle::current().spawn(future))​
    }​
​
    fn block_on<F: Future>(&self, future: F) -> F::Output {​
        Handle::current().block_on(future)​
    }​
}​
​
#[tokio::main]​
async fn main() {​
    let _guard = init_tracing_log("info", "temp/logs", "app.log");​
    let ak = env::var("TOS_ACCESS_KEY").unwrap_or("".to_string());​
    let sk = env::var("TOS_SECRET_KEY").unwrap_or("".to_string());​
    let endpoint = "https://tos-cn-beijing.volces.com";​
    let region = "cn-beijing";​
    let client = tos::builder::<TokioRuntime>()​
        .connection_timeout(3000)​
        .request_timeout(10000)​
        .max_retry_count(3)​
        .ak(ak)​
        .sk(sk)​
        .region(region)​
        .endpoint(endpoint)​
        .build().unwrap();​
​
    // Create input with default expiration (3600 seconds)​
    let input = PreSignedPostSignatureInput::new_with_key("example-bucket", "test-object.txt");​
    let output = client.pre_signed_post_signature(&input);​
​
    match output {​
        Ok(output) => {​
            println!("origin_policy: {}", output.origin_policy());​
            println!("policy: {}", output.policy());​
            println!("algorithm: {}", output.algorithm());​
            println!("credential: {}", output.credential());​
            println!("date: {}", output.date());​
            println!("signature: {}", output.signature());​
        }​
        Err(err) => {​
            match err {​
                TosError::TosClientError { message, .. } => {​
                    println!("Client error: {}", message);​
                }​
                TosError::TosServerError { request_id, ec, code, .. } => {​
                    println!("Server error: request_id: {}, ec: {}, code: {}", request_id, ec, code);​
                }​
            }​
        }​
    }​
}​