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forked from wrenn/wrenn

Add background process execution API

Start long-running processes (web servers, daemons) without blocking the
HTTP request. Leverages envd's existing background process support
(context.Background(), List, Connect, SendSignal RPCs) and wires it
through the host agent and control plane layers.

New API surface:
- POST /v1/capsules/{id}/exec with background:true → 202 {pid, tag}
- GET /v1/capsules/{id}/processes → list running processes
- DELETE /v1/capsules/{id}/processes/{selector} → kill by PID or tag
- WS /v1/capsules/{id}/processes/{selector}/stream → reconnect to output

The {selector} param auto-detects: numeric = PID, string = tag.
Tags are auto-generated as "proc-" + 8 hex chars if not provided.
This commit is contained in:
2026-04-14 03:57:01 +06:00
parent 962860ba74
commit 516890c49a
10 changed files with 1876 additions and 73 deletions

View File

@ -0,0 +1,266 @@
package api
import (
"context"
"log/slog"
"net/http"
"strconv"
"time"
"connectrpc.com/connect"
"github.com/go-chi/chi/v5"
"github.com/gorilla/websocket"
"github.com/jackc/pgx/v5/pgtype"
"git.omukk.dev/wrenn/wrenn/internal/auth"
"git.omukk.dev/wrenn/wrenn/internal/db"
"git.omukk.dev/wrenn/wrenn/internal/id"
"git.omukk.dev/wrenn/wrenn/internal/lifecycle"
pb "git.omukk.dev/wrenn/wrenn/proto/hostagent/gen"
)
type processHandler struct {
db *db.Queries
pool *lifecycle.HostClientPool
}
func newProcessHandler(db *db.Queries, pool *lifecycle.HostClientPool) *processHandler {
return &processHandler{db: db, pool: pool}
}
// processResponse is a single entry in the process list.
type processResponse struct {
PID uint32 `json:"pid"`
Tag string `json:"tag,omitempty"`
Cmd string `json:"cmd"`
Args []string `json:"args,omitempty"`
}
// processListResponse wraps the list of processes.
type processListResponse struct {
Processes []processResponse `json:"processes"`
}
// ListProcesses handles GET /v1/capsules/{id}/processes.
func (h *processHandler) ListProcesses(w http.ResponseWriter, r *http.Request) {
sandboxIDStr := chi.URLParam(r, "id")
ctx := r.Context()
ac := auth.MustFromContext(ctx)
sandboxID, err := id.ParseSandboxID(sandboxIDStr)
if err != nil {
writeError(w, http.StatusBadRequest, "invalid_request", "invalid sandbox ID")
return
}
sb, err := h.db.GetSandboxByTeam(ctx, db.GetSandboxByTeamParams{ID: sandboxID, TeamID: ac.TeamID})
if err != nil {
writeError(w, http.StatusNotFound, "not_found", "sandbox not found")
return
}
if sb.Status != "running" {
writeError(w, http.StatusConflict, "invalid_state", "sandbox is not running (status: "+sb.Status+")")
return
}
agent, err := agentForHost(ctx, h.db, h.pool, sb.HostID)
if err != nil {
writeError(w, http.StatusServiceUnavailable, "host_unavailable", "sandbox host is not reachable")
return
}
resp, err := agent.ListProcesses(ctx, connect.NewRequest(&pb.ListProcessesRequest{
SandboxId: sandboxIDStr,
}))
if err != nil {
status, code, msg := agentErrToHTTP(err)
writeError(w, status, code, msg)
return
}
procs := make([]processResponse, 0, len(resp.Msg.Processes))
for _, p := range resp.Msg.Processes {
procs = append(procs, processResponse{
PID: p.Pid,
Tag: p.Tag,
Cmd: p.Cmd,
Args: p.Args,
})
}
writeJSON(w, http.StatusOK, processListResponse{Processes: procs})
}
// KillProcess handles DELETE /v1/capsules/{id}/processes/{selector}.
// The selector can be a numeric PID or a string tag.
func (h *processHandler) KillProcess(w http.ResponseWriter, r *http.Request) {
sandboxIDStr := chi.URLParam(r, "id")
selectorStr := chi.URLParam(r, "selector")
ctx := r.Context()
ac := auth.MustFromContext(ctx)
sandboxID, err := id.ParseSandboxID(sandboxIDStr)
if err != nil {
writeError(w, http.StatusBadRequest, "invalid_request", "invalid sandbox ID")
return
}
sb, err := h.db.GetSandboxByTeam(ctx, db.GetSandboxByTeamParams{ID: sandboxID, TeamID: ac.TeamID})
if err != nil {
writeError(w, http.StatusNotFound, "not_found", "sandbox not found")
return
}
if sb.Status != "running" {
writeError(w, http.StatusConflict, "invalid_state", "sandbox is not running (status: "+sb.Status+")")
return
}
agent, err := agentForHost(ctx, h.db, h.pool, sb.HostID)
if err != nil {
writeError(w, http.StatusServiceUnavailable, "host_unavailable", "sandbox host is not reachable")
return
}
// Build the kill request with PID or tag selector.
killReq := &pb.KillProcessRequest{
SandboxId: sandboxIDStr,
Signal: "SIGKILL",
}
if sig := r.URL.Query().Get("signal"); sig == "SIGTERM" {
killReq.Signal = "SIGTERM"
}
if pid, err := strconv.ParseUint(selectorStr, 10, 32); err == nil {
killReq.Selector = &pb.KillProcessRequest_Pid{Pid: uint32(pid)}
} else {
killReq.Selector = &pb.KillProcessRequest_Tag{Tag: selectorStr}
}
if _, err := agent.KillProcess(ctx, connect.NewRequest(killReq)); err != nil {
status, code, msg := agentErrToHTTP(err)
writeError(w, status, code, msg)
return
}
w.WriteHeader(http.StatusNoContent)
}
// wsProcessOut is the JSON message sent to the WebSocket client.
type wsProcessOut struct {
Type string `json:"type"` // "start", "stdout", "stderr", "exit", "error"
PID uint32 `json:"pid,omitempty"` // only for "start"
Data string `json:"data,omitempty"` // only for "stdout", "stderr", "error"
ExitCode *int32 `json:"exit_code,omitempty"` // only for "exit"
}
// ConnectProcess handles WS /v1/capsules/{id}/processes/{selector}/stream.
func (h *processHandler) ConnectProcess(w http.ResponseWriter, r *http.Request) {
sandboxIDStr := chi.URLParam(r, "id")
selectorStr := chi.URLParam(r, "selector")
ctx := r.Context()
ac := auth.MustFromContext(ctx)
sandboxID, err := id.ParseSandboxID(sandboxIDStr)
if err != nil {
writeError(w, http.StatusBadRequest, "invalid_request", "invalid sandbox ID")
return
}
sb, err := h.db.GetSandboxByTeam(ctx, db.GetSandboxByTeamParams{ID: sandboxID, TeamID: ac.TeamID})
if err != nil {
writeError(w, http.StatusNotFound, "not_found", "sandbox not found")
return
}
if sb.Status != "running" {
writeError(w, http.StatusConflict, "invalid_state", "sandbox is not running (status: "+sb.Status+")")
return
}
agent, err := agentForHost(ctx, h.db, h.pool, sb.HostID)
if err != nil {
writeError(w, http.StatusServiceUnavailable, "host_unavailable", "sandbox host is not reachable")
return
}
conn, err := upgrader.Upgrade(w, r, nil)
if err != nil {
slog.Error("process stream websocket upgrade failed", "error", err)
return
}
defer conn.Close()
// Build the connect request with PID or tag selector.
connectReq := &pb.ConnectProcessRequest{
SandboxId: sandboxIDStr,
}
if pid, err := strconv.ParseUint(selectorStr, 10, 32); err == nil {
connectReq.Selector = &pb.ConnectProcessRequest_Pid{Pid: uint32(pid)}
} else {
connectReq.Selector = &pb.ConnectProcessRequest_Tag{Tag: selectorStr}
}
streamCtx, cancel := context.WithCancel(ctx)
defer cancel()
stream, err := agent.ConnectProcess(streamCtx, connect.NewRequest(connectReq))
if err != nil {
sendProcessWSError(conn, "failed to connect to process: "+err.Error())
return
}
defer stream.Close()
// Listen for client disconnect in a goroutine.
go func() {
for {
_, _, err := conn.ReadMessage()
if err != nil {
cancel()
return
}
}
}()
// Forward stream events to WebSocket.
for stream.Receive() {
resp := stream.Msg()
switch ev := resp.Event.(type) {
case *pb.ConnectProcessResponse_Start:
writeWSJSON(conn, wsProcessOut{Type: "start", PID: ev.Start.Pid})
case *pb.ConnectProcessResponse_Data:
switch o := ev.Data.Output.(type) {
case *pb.ExecStreamData_Stdout:
writeWSJSON(conn, wsProcessOut{Type: "stdout", Data: string(o.Stdout)})
case *pb.ExecStreamData_Stderr:
writeWSJSON(conn, wsProcessOut{Type: "stderr", Data: string(o.Stderr)})
}
case *pb.ConnectProcessResponse_End:
exitCode := ev.End.ExitCode
writeWSJSON(conn, wsProcessOut{Type: "exit", ExitCode: &exitCode})
}
}
if err := stream.Err(); err != nil {
if streamCtx.Err() == nil {
sendProcessWSError(conn, err.Error())
}
}
// Update last active using a fresh context.
updateCtx, updateCancel := context.WithTimeout(context.Background(), 5*time.Second)
defer updateCancel()
if err := h.db.UpdateLastActive(updateCtx, db.UpdateLastActiveParams{
ID: sandboxID,
LastActiveAt: pgtype.Timestamptz{
Time: time.Now(),
Valid: true,
},
}); err != nil {
slog.Warn("failed to update last active after process stream", "sandbox_id", sandboxIDStr, "error", err)
}
}
func sendProcessWSError(conn *websocket.Conn, msg string) {
writeWSJSON(conn, wsProcessOut{Type: "error", Data: msg})
}