refactor(truncation): effectify TruncateService, delete Scheduler (#17957)

packages/opencode/src/tool/truncate-effect.ts

@@ -0,0 +1,140 @@
+import { NodeFileSystem, NodePath } from "@effect/platform-node"
+import { Cause, Duration, Effect, FileSystem, Layer, Schedule, ServiceMap } from "effect"
+import path from "path"
+import type { Agent } from "../agent/agent"
+import { PermissionEffect } from "../permission/service"
+import { Identifier } from "../id/id"
+import { Log } from "../util/log"
+import { ToolID } from "./schema"
+import { TRUNCATION_DIR } from "./truncation-dir"
+
+export namespace TruncateEffect {
+  const log = Log.create({ service: "truncation" })
+  const RETENTION = Duration.days(7)
+
+  export const MAX_LINES = 2000
+  export const MAX_BYTES = 50 * 1024
+  export const DIR = TRUNCATION_DIR
+  export const GLOB = path.join(TRUNCATION_DIR, "*")
+
+  export type Result = { content: string; truncated: false } | { content: string; truncated: true; outputPath: string }
+
+  export interface Options {
+    maxLines?: number
+    maxBytes?: number
+    direction?: "head" | "tail"
+  }
+
+  function hasTaskTool(agent?: Agent.Info) {
+    if (!agent?.permission) return false
+    return PermissionEffect.evaluate("task", "*", agent.permission).action !== "deny"
+  }
+
+  export interface Api {
+    readonly cleanup: () => Effect.Effect<void>
+    /**
+     * Returns output unchanged when it fits within the limits, otherwise writes the full text
+     * to the truncation directory and returns a preview plus a hint to inspect the saved file.
+     */
+    readonly output: (text: string, options?: Options, agent?: Agent.Info) => Effect.Effect<Result>
+  }
+
+  export class Service extends ServiceMap.Service<Service, Api>()("@opencode/Truncate") {}
+
+  export const layer = Layer.effect(
+    Service,
+    Effect.gen(function* () {
+      const fs = yield* FileSystem.FileSystem
+
+      const cleanup = Effect.fn("TruncateEffect.cleanup")(function* () {
+        const cutoff = Identifier.timestamp(Identifier.create("tool", false, Date.now() - Duration.toMillis(RETENTION)))
+        const entries = yield* fs.readDirectory(TRUNCATION_DIR).pipe(
+          Effect.map((all) => all.filter((name) => name.startsWith("tool_"))),
+          Effect.catch(() => Effect.succeed([])),
+        )
+        for (const entry of entries) {
+          if (Identifier.timestamp(entry) >= cutoff) continue
+          yield* fs.remove(path.join(TRUNCATION_DIR, entry)).pipe(Effect.catch(() => Effect.void))
+        }
+      })
+
+      const output = Effect.fn("TruncateEffect.output")(function* (
+        text: string,
+        options: Options = {},
+        agent?: Agent.Info,
+      ) {
+        const maxLines = options.maxLines ?? MAX_LINES
+        const maxBytes = options.maxBytes ?? MAX_BYTES
+        const direction = options.direction ?? "head"
+        const lines = text.split("\n")
+        const totalBytes = Buffer.byteLength(text, "utf-8")
+
+        if (lines.length <= maxLines && totalBytes <= maxBytes) {
+          return { content: text, truncated: false } as const
+        }
+
+        const out: string[] = []
+        let i = 0
+        let bytes = 0
+        let hitBytes = false
+
+        if (direction === "head") {
+          for (i = 0; i < lines.length && i < maxLines; i++) {
+            const size = Buffer.byteLength(lines[i], "utf-8") + (i > 0 ? 1 : 0)
+            if (bytes + size > maxBytes) {
+              hitBytes = true
+              break
+            }
+            out.push(lines[i])
+            bytes += size
+          }
+        } else {
+          for (i = lines.length - 1; i >= 0 && out.length < maxLines; i--) {
+            const size = Buffer.byteLength(lines[i], "utf-8") + (out.length > 0 ? 1 : 0)
+            if (bytes + size > maxBytes) {
+              hitBytes = true
+              break
+            }
+            out.unshift(lines[i])
+            bytes += size
+          }
+        }
+
+        const removed = hitBytes ? totalBytes - bytes : lines.length - out.length
+        const unit = hitBytes ? "bytes" : "lines"
+        const preview = out.join("\n")
+        const file = path.join(TRUNCATION_DIR, ToolID.ascending())
+
+        yield* fs.makeDirectory(TRUNCATION_DIR, { recursive: true }).pipe(Effect.orDie)
+        yield* fs.writeFileString(file, text).pipe(Effect.orDie)
+
+        const hint = hasTaskTool(agent)
+          ? `The tool call succeeded but the output was truncated. Full output saved to: ${file}\nUse the Task tool to have explore agent process this file with Grep and Read (with offset/limit). Do NOT read the full file yourself - delegate to save context.`
+          : `The tool call succeeded but the output was truncated. Full output saved to: ${file}\nUse Grep to search the full content or Read with offset/limit to view specific sections.`
+
+        return {
+          content:
+            direction === "head"
+              ? `${preview}\n\n...${removed} ${unit} truncated...\n\n${hint}`
+              : `...${removed} ${unit} truncated...\n\n${hint}\n\n${preview}`,
+          truncated: true,
+          outputPath: file,
+        } as const
+      })
+
+      yield* cleanup().pipe(
+        Effect.catchCause((cause) => {
+          log.error("truncation cleanup failed", { cause: Cause.pretty(cause) })
+          return Effect.void
+        }),
+        Effect.repeat(Schedule.spaced(Duration.hours(1))),
+        Effect.delay(Duration.minutes(1)),
+        Effect.forkScoped,
+      )
+
+      return Service.of({ cleanup, output })
+    }),
+  )
+
+  export const defaultLayer = layer.pipe(Layer.provide(NodeFileSystem.layer), Layer.provide(NodePath.layer))
+}