brianmcgee
6c5328a54f
Protects against slow or unresponsive nodes during file transfers by enforcing per-operation deadlines and adding an overall timeout for file downloads.
- adds `DeadlineConn` wrapper that resets read/write deadlines after each I/O operation, ensuring data must flow continuously
- replaces `FileClient` with `FileDownloader` - a background download manager that:
- limits concurrent downloads to 2x CPU count
- deduplicates in-flight requests for the same file
- cancels obsolete downloads when a newer file version becomes available
- enforces an overall download timeout (default 10 minutes)
Closes #286
41 lines
1.2 KiB
Go
41 lines
1.2 KiB
Go
package net
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import (
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"net"
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"time"
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)
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// DeadlineConn wraps a net.Conn with per-operation deadline resets.
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// This protects against slow or unresponsive nodes by ensuring each read/write must complete within the specified
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// timeout.
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//
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// Each Read() call sets a fresh read deadline, and each Write() call sets a fresh write deadline.
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// As long as data flows, the deadlines are continually extended.
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// If no bytes arrive/are sent within the timeout, the operation fails with os.ErrDeadlineExceeded.
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type DeadlineConn struct {
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net.Conn
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ReadDeadline time.Duration
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WriteDeadline time.Duration
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}
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// Read implements io.Reader with per-read deadline enforcement.
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func (c *DeadlineConn) Read(p []byte) (int, error) {
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if c.ReadDeadline > 0 {
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_ = c.SetReadDeadline(time.Now().Add(c.ReadDeadline))
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}
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//nolint:wrapcheck // io.Reader interface requires unwrapped errors
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return c.Conn.Read(p)
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}
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// Write implements io.Writer with per-write deadline enforcement.
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func (c *DeadlineConn) Write(p []byte) (int, error) {
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if c.WriteDeadline > 0 {
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_ = c.SetWriteDeadline(time.Now().Add(c.WriteDeadline))
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}
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//nolint:wrapcheck // io.Writer interface requires unwrapped errors
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return c.Conn.Write(p)
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}
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