file cache -- also use for attr's directly even if readdir not used

websocketfs/lib/metadata-file.ts

@@ -3,9 +3,9 @@ import { stat, readFile } from "fs/promises";
 import { decode } from "lz4";
 import binarySearch from "binarysearch";
 import { symbolicToMode } from "./util";
-import { join } from "path";
 
 const log = debug("websocketfs:metadata-file");
+const log_cache = debug("cache");
 
 const METADATA_FILE_INTERVAL_MS = 3000;
 
@@ -99,22 +99,60 @@ export class MetadataFile {
     }
   };
 
+  private find = (path: string): number => {
+    return binarySearch(
+      this.metadataFileContents,
+      path,
+      (value: string, find: string) => {
+        const name = "/" + value.split("\0")[0];
+        if (name < find) {
+          return -1;
+        }
+        if (name > find) {
+          return 1;
+        }
+        return 0;
+      },
+    );
+  };
+
+  private cacheAttrs = (i: number) => {
+    const v = this.metadataFileContents[i].split("\0");
+    const data = v[1].split(" ");
+    const mtime = new Date(parseFloat(data[0]) * 1000);
+    const attr = {
+      mtime,
+      atime: new Date(parseFloat(data[1]) * 1000),
+      ctime: mtime,
+      blocks: parseInt(data[2]),
+      size: parseInt(data[3]),
+      mode: symbolicToMode(data[4]),
+      flags: 0,
+      uid: 0,
+      gid: 0,
+    };
+    this.attrCache.set("/" + v[0], { attr });
+    return { attr };
+  };
+
+  getattr = (path: string): { errno?: number; attr? } => {
+    const i = this.find(path);
+    if (i == -1) {
+      // error -- no such file
+      return { errno: -2 };
+    } else {
+      return this.cacheAttrs(i);
+    }
+  };
+
   readdir = (path: string) => {
     if (!this.isReady()) {
       throw Error("MetadataFile is not ready");
     }
     log("readdir", path);
-    let i = binarySearch(this.metadataFileContents, path, (value, find) => {
-      const path = "/" + value.split("\0")[0];
-      if (path < find) {
-        return -1;
-      }
-      if (path > find) {
-        return 1;
-      }
-      return 0;
-    });
+    let i = this.find(path);
     if (i == -1) {
+      log_cache("readdir ", path, " WORKED");
       log("readdir", path, " -- does not exist");
       return [];
     }
@@ -125,32 +163,20 @@ export class MetadataFile {
       const v = this.metadataFileContents[i].split("\0");
       const name = "/" + v[0];
       if (!name.startsWith(path)) {
-        // definitely done.
+        // done.
         break;
       }
       if (name.startsWith(pathDir)) {
         const filename = name.slice(pathDir.length);
         if (!filename.includes("/")) {
           filenames.push(filename);
-          const data = v[1].split(" ");
-          const mtime = new Date(parseFloat(data[0]) * 1000);
-          const attr = {
-            mtime,
-            atime: new Date(parseFloat(data[1]) * 1000),
-            ctime: mtime,
-            blocks: parseInt(data[2]),
-            size: parseInt(data[3]),
-            mode: symbolicToMode(data[4]),
-            flags: 0,
-            uid: 0,
-            gid: 0,
-          };
-          this.attrCache.set(join(path, filename), { attr });
+          this.cacheAttrs(i);
         }
       }
       i += 1;
     }
     this.dirCache.set(path, filenames);
+    log_cache("readdir ", path, " WORKED");
     return filenames;
   };
 }

websocketfs/lib/sftp-fuse.ts

@@ -26,6 +26,7 @@ import { MetadataFile } from "./metadata-file";
 export type { IClientOptions };
 
 const log = debug("websocketfs:sftp-fuse");
+const log_cache = debug("cache");
 
 type Callback = Function;
 
@@ -266,6 +267,12 @@ export default class SftpFuse {
       cb(errno ?? 0, attr);
       return;
     }
+    if (this.meta?.isReady()) {
+      const { errno, attr } = this.meta.getattr(path);
+      cb(errno ?? 0, attr);
+      return;
+    }
+    log_cache("getattr -- cache miss", path);
     log("getattr -- cache miss", path);
     this.sftp.lstat(path, (err, attr) => {
       // log("getattr -- lstat", { path, err, attr });
@@ -291,6 +298,12 @@ export default class SftpFuse {
       cb(errno ?? 0, attr);
       return;
     }
+    if (this.meta?.isReady()) {
+      const { errno, attr } = this.meta.getattr(path);
+      cb(errno ?? 0, attr);
+      return;
+    }
+    log_cache("fgetattr -- cache miss", path);
     const handle = this.sftp.fileDescriptorToHandle(fd);
     this.sftp.fstat(handle, (err, attr) => {
       if (err) {
@@ -381,14 +394,14 @@ export default class SftpFuse {
       cb(0, this.dirCache.get(path));
       return;
     }
-
     if (this.meta?.isReady() && !path.startsWith(".")) {
       try {
         cb(0, this.meta.readdir(path));
       } catch (err) {
         log("readdir error using metadata file cache:", err);
       }
     }
+    log_cache("readdir -- cache miss", path);
 
     try {
       let handle;

websocketfs/package.json

@@ -1,6 +1,6 @@
 {
   "name": "websocketfs",
-  "version": "0.12.1",
+  "version": "0.12.2",
   "description": "Like sshfs, but over a WebSocket",
   "main": "./dist/lib/index.js",
   "scripts": {