Struct SnapshotDownloader 

pub struct SnapshotDownloader { /* private fields */ }

Downloads snapshot archives from HTTP/HTTPS and file:// URLs.

Provides secure, reliable downloading with automatic retry logic for network sources and direct file copying for local sources.

Features

• HTTP/HTTPS: Automatic retry with exponential backoff, progress tracking
• Local Files: Direct copying from file:// URLs with validation
• Safety: Size limits, disk space checks, timeout protection
• Monitoring: Progress reporting and detailed error messages

Examples

use std::path::Path;

use hopr_chain_indexer::snapshot::download::SnapshotDownloader;

let downloader = SnapshotDownloader::new()?;

// Download from HTTPS
downloader
    .download_snapshot(
        "https://snapshots.hoprnet.org/logs.tar.xz",
        Path::new("/tmp/snapshot.tar.xz"),
    )
    .await?;

// Copy from local file
downloader
    .download_snapshot("file:///backups/snapshot.tar.xz", Path::new("/tmp/snapshot.tar.xz"))
    .await?;

Implementations

impl SnapshotDownloader

pub fn new() -> SnapshotResult<Self>

Creates a new snapshot downloader with default configuration

pub fn with_config(config: DownloadConfig) -> SnapshotResult<Self>

Creates a new snapshot downloader with custom configuration

pub async fn download_snapshot( &self, url: &str, target_path: &Path, ) -> SnapshotResult<()>

Downloads a snapshot from the given URL to the target path.

Supports HTTP/HTTPS URLs with retry logic and file:// URLs for local files.

Arguments

• url - Source URL (http://, https://, or file:// scheme)
• target_path - Destination file path

Errors

Returns SnapshotError for network failures, file system errors, or validation failures.

pub async fn download_snapshot_with_retry( &self, url: &str, target_path: &Path, max_retries: u32, ) -> SnapshotResult<()>

Downloads a snapshot with configurable retry logic.

Implements exponential backoff between retry attempts for HTTP/HTTPS URLs. Local file:// URLs are handled without retry logic. Certain errors (like 4xx HTTP status codes or insufficient disk space) will not be retried.

Arguments

• url - The HTTP/HTTPS or file:// URL to download/copy from
• target_path - Local path where the downloaded file will be saved
• max_retries - Maximum number of retry attempts (ignored for file:// URLs)

Errors

Returns SnapshotError for various failure conditions including:

• Network errors (with retry)
• HTTP errors (4xx without retry, 5xx with retry)
• Insufficient disk space (without retry)
• File size exceeding limits (without retry)

pub async fn check_disk_space(&self, dir: &Path) -> SnapshotResult<()>

Checks if there’s sufficient disk space available for download and extraction.

Validates that the target directory has at least 3x the maximum download size available to account for:

1. The downloaded archive
2. Extracted files
3. Safety margin for system operations

Arguments

• dir - Directory to check for available space

Errors

Returns SnapshotError::InsufficientSpace if available space is below requirements