feat(opencode): add filesystem read and list routes

packages/core/src/location-filesystem.ts

@@ -3,6 +3,7 @@ export * as LocationFileSystem from "./location-filesystem"
 import path from "path"
 import { pathToFileURL } from "url"
 import { Context, Effect, Layer, Schema } from "effect"
+import { AppFileSystem } from "./filesystem"
 import { Location } from "./location"
 import { NonNegativeInt, PositiveInt, RelativePath } from "./schema"
 
@@ -11,13 +12,22 @@ export const ReadInput = Schema.Struct({
 })
 export type ReadInput = typeof ReadInput.Type
 
-export class Content extends Schema.Class<Content>("LocationFileSystem.Content")({
-  type: Schema.Literals(["text", "binary"]),
+export class TextContent extends Schema.Class<TextContent>("LocationFileSystem.TextContent")({
+  type: Schema.Literal("text"),
   content: Schema.String,
-  encoding: Schema.Literal("base64").pipe(Schema.optional),
-  mime: Schema.String.pipe(Schema.optional),
+  mime: Schema.String,
 }) {}
 
+export class BinaryContent extends Schema.Class<BinaryContent>("LocationFileSystem.BinaryContent")({
+  type: Schema.Literal("binary"),
+  content: Schema.String,
+  encoding: Schema.Literal("base64"),
+  mime: Schema.String,
+}) {}
+
+export const Content = Schema.Union([TextContent, BinaryContent]).pipe(Schema.toTaggedUnion("type"))
+export type Content = typeof Content.Type
+
 export const ListInput = Schema.Struct({
   path: RelativePath.pipe(Schema.optional),
 })
@@ -70,7 +80,33 @@ export class Service extends Context.Service<Service, Interface>()("@opencode/v2
 export const locationLayer = Layer.effect(
   Service,
   Effect.gen(function* () {
+    const fs = yield* AppFileSystem.Service
     const location = yield* Location.Service
+    const root = yield* fs.realPath(location.directory).pipe(Effect.orDie)
+    const resolve = Effect.fnUntraced(function* (input?: RelativePath) {
+      if (input && path.isAbsolute(input)) return yield* Effect.die(new Error("Path must be relative to the location"))
+      const absolute = path.resolve(location.directory, input ?? ".")
+      if (!AppFileSystem.contains(location.directory, absolute))
+        return yield* Effect.die(new Error("Path escapes the location"))
+      const real = yield* fs.realPath(absolute).pipe(Effect.orDie)
+      if (!AppFileSystem.contains(root, real)) return yield* Effect.die(new Error("Path escapes the location"))
+      return { absolute, real }
+    })
+    const entry = Effect.fnUntraced(function* (absolute: string) {
+      const real = yield* fs.realPath(absolute).pipe(Effect.catch(() => Effect.void))
+      if (!real) return
+      if (!AppFileSystem.contains(root, real)) return
+      const info = yield* fs.stat(real).pipe(Effect.catch(() => Effect.void))
+      if (!info) return
+      const type = info.type === "Directory" ? "directory" : info.type === "File" ? "file" : undefined
+      if (!type) return
+      return new Entry({
+        path: RelativePath.make(path.relative(location.directory, absolute)),
+        uri: pathToFileURL(real).href,
+        type,
+        mime: type === "directory" ? "application/x-directory" : AppFileSystem.mimeType(real),
+      })
+    })
     const entries = [
       new Entry({
         path: RelativePath.make("README.md"),
@@ -87,11 +123,42 @@ export const locationLayer = Layer.effect(
     ]
 
     return Service.of({
-      read: Effect.fn("LocationFileSystem.read")(function* () {
-        return new Content({ type: "text", content: "# opencode\n", mime: "text/markdown" })
+      read: Effect.fn("LocationFileSystem.read")(function* (input) {
+        const file = yield* resolve(input.path)
+        const info = yield* fs.stat(file.real).pipe(Effect.orDie)
+        if (info.type !== "File") return yield* Effect.die(new Error("Path is not a file"))
+        const bytes = yield* fs.readFile(file.real).pipe(Effect.orDie)
+        const mime = AppFileSystem.mimeType(file.real)
+        if (!bytes.includes(0)) {
+          const content = yield* Effect.sync(() => new TextDecoder("utf-8", { fatal: true }).decode(bytes)).pipe(
+            Effect.option,
+          )
+          if (content._tag === "Some") return new TextContent({ type: "text", content: content.value, mime })
+        }
+        return new BinaryContent({
+          type: "binary",
+          content: Buffer.from(bytes).toString("base64"),
+          encoding: "base64",
+          mime,
+        })
       }),
-      list: Effect.fn("LocationFileSystem.list")(function* () {
-        return entries
+      list: Effect.fn("LocationFileSystem.list")(function* (input = {}) {
+        const directory = yield* resolve(input.path)
+        const info = yield* fs.stat(directory.real).pipe(Effect.orDie)
+        if (info.type !== "Directory") return yield* Effect.die(new Error("Path is not a directory"))
+        return yield* fs.readDirectoryEntries(directory.real).pipe(
+          Effect.orDie,
+          Effect.flatMap((items) =>
+            Effect.forEach(items, (item) => entry(path.join(directory.absolute, item.name)), {
+              concurrency: "unbounded",
+            }),
+          ),
+          Effect.map((items) =>
+            items
+              .filter((item): item is Entry => item !== undefined)
+              .sort((a, b) => (a.type === b.type ? a.path.localeCompare(b.path) : a.type === "directory" ? -1 : 1)),
+          ),
+        )
       }),
       find: Effect.fn("LocationFileSystem.find")(function* (input) {
         return entries.filter((entry) => input.type === undefined || entry.type === input.type).slice(0, input.limit)

packages/core/test/location-filesystem.test.ts

@@ -0,0 +1,92 @@
+import fs from "fs/promises"
+import path from "path"
+import { pathToFileURL } from "url"
+import { describe, expect } from "bun:test"
+import { Effect, Exit, Layer } from "effect"
+import { AppFileSystem } from "@opencode-ai/core/filesystem"
+import { Location } from "@opencode-ai/core/location"
+import { LocationFileSystem } from "@opencode-ai/core/location-filesystem"
+import { AbsolutePath, RelativePath } from "@opencode-ai/core/schema"
+import { tmpdir } from "./fixture/tmpdir"
+import { location } from "./fixture/location"
+import { it } from "./lib/effect"
+
+function provide(directory: string) {
+  return Effect.provide(
+    LocationFileSystem.locationLayer.pipe(
+      Layer.provide(
+        Layer.mergeAll(
+          AppFileSystem.defaultLayer,
+          Layer.succeed(Location.Service, Location.Service.of(location({ directory: AbsolutePath.make(directory) }))),
+        ),
+      ),
+    ),
+  )
+}
+
+function withTmp<A, E, R>(f: (directory: string) => Effect.Effect<A, E, R>) {
+  return Effect.acquireRelease(
+    Effect.promise(() => tmpdir()),
+    (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]()),
+  ).pipe(Effect.flatMap((tmp) => f(tmp.path).pipe(provide(tmp.path))))
+}
+
+describe("LocationFileSystem", () => {
+  it.live("reads text and binary files", () =>
+    withTmp((directory) =>
+      Effect.gen(function* () {
+        yield* Effect.promise(() => fs.writeFile(path.join(directory, "hello.txt"), "hello"))
+        yield* Effect.promise(() => fs.writeFile(path.join(directory, "data.bin"), Buffer.from([0, 1, 2])))
+        const service = yield* LocationFileSystem.Service
+
+        expect(yield* service.read({ path: RelativePath.make("hello.txt") })).toEqual({
+          type: "text",
+          content: "hello",
+          mime: "text/plain",
+        })
+        expect(yield* service.read({ path: RelativePath.make("data.bin") })).toEqual({
+          type: "binary",
+          content: "AAEC",
+          encoding: "base64",
+          mime: "application/octet-stream",
+        })
+      }),
+    ),
+  )
+
+  it.live("lists direct children with relative paths and resolved URIs", () =>
+    withTmp((directory) =>
+      Effect.gen(function* () {
+        yield* Effect.promise(() => fs.mkdir(path.join(directory, "src")))
+        yield* Effect.promise(() => fs.writeFile(path.join(directory, "README.md"), "# Test"))
+        const service = yield* LocationFileSystem.Service
+
+        expect(yield* service.list()).toEqual([
+          {
+            path: RelativePath.make("src"),
+            uri: pathToFileURL(path.join(directory, "src")).href,
+            type: "directory",
+            mime: "application/x-directory",
+          },
+          {
+            path: RelativePath.make("README.md"),
+            uri: pathToFileURL(path.join(directory, "README.md")).href,
+            type: "file",
+            mime: "text/markdown",
+          },
+        ])
+      }),
+    ),
+  )
+
+  it.live("rejects paths outside the location", () =>
+    withTmp((directory) =>
+      Effect.gen(function* () {
+        const service = yield* LocationFileSystem.Service
+        expect(
+          Exit.isFailure(yield* service.read({ path: RelativePath.make("../outside.txt") }).pipe(Effect.exit)),
+        ).toBe(true)
+      }),
+    ),
+  )
+})