Go Chi Context-Aware Goroutine Lifetime & Stream Drain Invariant

Q: How does adopting this rule prevent AI hallucinations?

This rule explicitly declares what the AI must avoid (Unbounded Goroutine Spawning and Unmonitored Channel Operations Leading to Resource Leaks on Aborted HTTP/3 Streams) and prescribes verified positive examples. Grounding the LLM with negative and positive pairs eliminates guesswork.

Q: Which AI coding environments are supported?

This specification is multi-platform compatible: Cursor (.cursor/rules/*.mdc & .cursorrules), Anthropic Claude Code (CLAUDE.md), Windsurf (.windsurfrules), Codex / Cline (AGENTS.md), and GitHub Copilot (.github/copilot-instructions.md).

Q: Can I combine this rule with other technology stacks?

Yes. Use the Interactive Stack Builder or download an Agent Pack to merge this rule with other frontend, backend, database, security, and DevOps rules without syntax collision.

Go Chi Context-Aware Goroutine Lifetime & Stream Drain Invariant

--- description: Go Chi Context-Aware Goroutine Lifetime & Stream Drain Invariant - Enforces deterministic goroutine termination and channel cancellation tied directly to request contexts within Go Chi HTTP services. Guarantees that client-initiated disconnects, QUIC stream resets, and HTTP/3 transport cancellations immediately tear down spawned worker routines and cleanly unblock pending channel transmissions to prevent cumulative memory and descriptor leaks. globs: **/*.go, cmd/**/*.go, internal/**/*.go, pkg/**/*.go alwaysApply: true verified_by: "agentrules.org" license: "CC-BY-4.0" source: "https://agentrules.org/rules/go-chi-context-cancellation-goroutine-lifetime" --- # Go Chi Context-Aware Goroutine Lifetime & Stream Drain Invariant > **Severity**: CRITICAL | **Category**: backend > **Anti-Pattern Warning**: Unbounded Goroutine Spawning and Unmonitored Channel Operations Leading to Resource Leaks on Aborted HTTP/3 Streams ## System Constraints You are a Principal Software Architect enforcing Go Chi Context-Aware Goroutine Lifetime Termination & Channel Cancellation Invariants. You must mandate that every goroutine spawned during the lifecycle of an HTTP request is tightly coupled to the incoming http.Request Context, uses structured concurrency mechanisms like errgroup, and ensures all channel sends and receives guard against context cancellation to prevent goroutine accumulation on severed HTTP/2 or HTTP/3 streams. ## Strict Guidelines - Engineers MUST ALWAYS propagate `r.Context()` to any background routine, database query, or outbound RPC spawned from a Chi HTTP handler. - Engineers MUST NOT perform unbuffered or unguarded channel sends within child goroutines; all channel writes must be multiplexed against `ctx.Done()` in a `select` statement. - Code SHOULD utilize structured concurrency primitives (such as `golang.org/x/sync/errgroup` initialized with `errgroup.WithContext(r.Context())`) to synchronize lifecycle termination. - Services MUST monitor QUIC/HTTP/3 client stream cancellations by honoring context cancellation prior to committing chunked HTTP responses. - Components NEVER detach goroutines via `context.Background()` or naked `go func()` within HTTP request handlers without an explicit out-of-band supervisor worker pool. ## Bad vs Good Implementations ### Unbounded Goroutine and Blocking Channel on HTTP Disconnect #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: When an HTTP/3 client aborts or resets a stream, the Chi handler exits via r.Context().Done(), leaving the child goroutine permanently blocked attempting to send to an unbuffered channel that will never be read again. ```go package handlers import ( "encoding/json" "net/http" "time" ) type MetricPayload struct { Data string `json:"data"` } func BadStreamHandler(w http.ResponseWriter, r *http.Request) { ch := make(chan MetricPayload) // ANTI-PATTERN: Fire-and-forget goroutine ignoring r.Context(). // If the HTTP/3 stream is reset or client disconnects, this goroutine // blocks indefinitely on the unbuffered channel write, leaking memory. go func() { time.Sleep(2 * time.Second) // simulate work ch <- MetricPayload{Data: "aggregated"} // blocks forever on abort! }() select { case res := <-ch: w.Header().Set("Content-Type", "application/json") _ = json.NewEncoder(w).Encode(res) case <-r.Context().Done(): // Handler exits, but child goroutine remains stranded in memory return } } ``` #### Production Standard (Correct) > **Standard**: The child goroutine monitors gCtx.Done() in all operations and sends over a buffered channel guarded by select. If an HTTP/3 stream aborts, r.Context() cancels, g.Wait() guarantees total unwinding of the child routine, preventing orphaned goroutines. ```go package handlers import ( "context" "encoding/json" "errors" "net/http" "time" "golang.org/x/sync/errgroup" ) type MetricPayload struct { Data string `json:"data"` } func GoodStreamHandler(w http.ResponseWriter, r *http.Request) { ctx := r.Context() g, gCtx := errgroup.WithContext(ctx) // Buffer channel to allow clean unblocking and guard send with context ch := make(chan MetricPayload, 1) g.Go(func() error { select { case <-gCtx.Done(): return gCtx.Err() case <-time.After(2 * time.Second): // simulate work respecting context } select { case ch <- MetricPayload{Data: "aggregated"}: return nil case <-gCtx.Done(): return gCtx.Err() } }) select { case <-ctx.Done(): _ = g.Wait() // Drain and confirm all workers unwind return case res := <-ch: if err := g.Wait(); err != nil && !errors.Is(err, context.Canceled) { http.Error(w, err.Error(), http.StatusInternalServerError) return } w.Header().Set("Content-Type", "application/json") _ = json.NewEncoder(w).Encode(res) } } ```

Architectural Specification & Invariant Rationale

Architectural Invariant Design: Go Chi Context-Aware Goroutine Lifetime & Stream Drain Invariant

Go Chi Context-Aware Goroutine Lifetime & Stream Drain Invariant defines an industrial-grade behavioral standard for backend engineering. Enforces deterministic goroutine termination and channel cancellation tied directly to request contexts within Go Chi HTTP services. Guarantees that client-initiated disconnects, QUIC stream resets, and HTTP/3 transport cancellations immediately tear down spawned worker routines and cleanly unblock pending channel transmissions to prevent cumulative memory and descriptor leaks. Modern software architectures require strict adherence to deterministic patterns to guarantee high availability, maintainability, and zero security vulnerabilities.

Framework Paradigm Shift & Drift MechanicsLLMs are trained on millions of open-source repositories containing outdated code, legacy idioms, and unpatched antipatterns. When coding assistants generate implementations for this stack, they default to common statistical tokens: Unbounded Goroutine Spawning and Unmonitored Channel Operations Leading to Resource Leaks on Aborted HTTP/3 Streams Without an explicit system instruction file, developers spend hours debugging silent failures.

Failure Modes & Production Blast Radius

Hazard Analysis: What Breaks Without This Rule

The following failure modes have been cataloged from hundreds of hours of production code reviews where AI assistants produced non-compliant implementations:

Failure Mode	AI Symptom (The Anti-Pattern)	Severity	Production Impact & Remedy
AI Hallucination & Deprecation Drift	Unbounded Goroutine Spawning and Unmonitored Channel Operations Leading to Resource Leaks on Aborted HTTP/3 Streams	Critical	Violating this industrial standard introduces regression bugs, security risks, and unexpected runtime failures in production. Enforce explicit behavioral system directives across all AI coding assistants in your repository.
Silent Architecture Inconsistency	AI assistants produce mixed paradigms across files, creating fragmented codebase conventions.	Medium	Increases cognitive load during code reviews and leads to maintenance debt across engineering teams. Pin project conventions in .cursor/rules, CLAUDE.md, and AGENTS.md so all team agents follow identical guardrails.

Architectural Directives in Detail

Step-by-Step Production Directives

Each rule constraint below is injected into the AI agent's system prompt to establish deterministic boundaries:

Engineers MUST ALWAYS propagate `r.Context()` to any background routine, database query, or outbound RPC spawned from a Chi HTTP handler.

Rationale:AI models frequently generate unconstrained code here because statistical language distributions lack project-specific architectural context. Mandating this directive ensures that generated code adheres to verified industrial production requirements.