babashka.fs
Cross-platform file system utilities for Clojure. Built on java.nio, works in JVM Clojure and babashka (built-in since v0.2.9).
Setup
deps.edn:
babashka/fs {:mvn/version "0.5.27"}
Leiningen:
[babashka/fs "0.5.27"]
See https://clojars.org/babashka/fs for the latest version.
Note: Built into babashka, no dependency needed if using bb.
Quick Start
(require '[babashka.fs :as fs])
;; Check file types
(fs/directory? ".") ;; => true
(fs/exists? "project.clj") ;; => true
(fs/regular-file? "README") ;; => true
;; Path manipulation
(str (fs/path "src" "app" "core.clj"))
;; => "src/app/core.clj"
(str (fs/absolutize "."))
;; => "/home/user/project"
;; List directory
(map str (fs/list-dir "src"))
;; => ("src/app" "src/test")
;; Find files
(map str (fs/glob "." "**/*.clj"))
;; => ("src/app/core.clj" "test/app/core_test.clj")
Common Operations
Path Creation and Manipulation
;; Build paths (fs/path "home" "user" "file.txt") ;; => #object[java.nio.file.Path] (fs/file "home" "user" "file.txt") ;; => #object[java.io.File] ;; Expand home directory (fs/expand-home "~/projects") ;; => #object[java.nio.file.Path "/home/user/projects"] ;; Get components (fs/file-name "/path/to/file.txt") ;; => "file.txt" (fs/parent "/path/to/file.txt") ;; => #object[Path "/path/to"] (fs/extension "file.clj") ;; => "clj" (split-ext "file.tar.gz") ;; => ["file.tar" "gz"] (strip-ext "file.clj") ;; => "file" ;; Normalize and resolve (fs/normalize "path/./to/../file") ;; => "path/file" (fs/absolutize "src") ;; => "/home/user/project/src" (fs/canonicalize "src") ;; => resolves symlinks + normalizes (fs/real-path "src") ;; => like canonicalize, requires existence
Directory Listing and Searching
;; List immediate children
(fs/list-dir "src")
;; => [#object[Path "src/core.clj"] #object[Path "src/util.clj"]]
;; List with glob filter
(fs/list-dir "src" "*.clj")
;; => [#object[Path "src/core.clj"]]
;; Glob search (recursive)
(fs/glob "." "**/*.clj") ;; all .clj files
(fs/glob "." "**{.clj,.cljc}") ;; .clj OR .cljc files
;; Match search (more control)
(fs/match "." "regex:.*\\.clj" {:recursive true})
;; Find files in PATH
(fs/which "java")
;; => #object[Path "/usr/bin/java"]
(fs/exec-paths) ;; all PATH directories as Paths
File Operations
;; Copy
(fs/copy "src.txt" "dest.txt")
(fs/copy "src.txt" "dest.txt" {:replace-existing true})
(fs/copy-tree "src-dir" "dest-dir") ;; recursive copy
;; Move
(fs/move "old.txt" "new.txt")
(fs/move "old.txt" "new.txt" {:replace-existing true})
;; Delete
(fs/delete "file.txt") ;; throws if not exists
(fs/delete-if-exists "file.txt") ;; safe delete
(fs/delete-tree "dir") ;; recursive delete (rm -rf)
(fs/delete-tree "dir" {:force true}) ;; delete read-only files too
Creating Files and Directories
;; Directories
(fs/create-dir "newdir") ;; single dir, parent must exist
(fs/create-dirs "path/to/newdir") ;; like mkdir -p
;; Files
(fs/create-file "empty.txt")
;; Temporary
(fs/create-temp-dir)
(fs/create-temp-dir {:prefix "myapp-"})
(fs/create-temp-file)
(fs/create-temp-file {:prefix "log-" :suffix ".txt"})
;; With auto-cleanup
(fs/with-temp-dir [tmp]
(fs/create-file (fs/path tmp "work.txt"))
;; ... do work ...
) ;; tmp deleted here
Reading and Writing
;; Read
(fs/read-all-bytes "file.bin") ;; => byte[]
(fs/read-all-lines "file.txt") ;; => ["line1" "line2"]
;; Write
(fs/write-bytes "out.bin" byte-array)
(fs/write-lines "out.txt" ["line1" "line2"])
(fs/write-lines "out.txt" ["more"] {:append true})
;; Update in place
(fs/update-file "config.edn"
#(str/replace % "localhost" "prod.example.com"))
File Metadata
;; Timestamps (fs/creation-time "file.txt") ;; => FileTime (fs/last-modified-time "file.txt") ;; => FileTime (fs/file-time->millis (fs/last-modified-time "file.txt")) ;; Set timestamps (fs/set-last-modified-time "file.txt" (System/currentTimeMillis)) ;; Size (fs/size "file.txt") ;; => bytes ;; Permissions (Unix/Linux) (fs/posix-file-permissions "file.sh") (fs/posix->str (fs/posix-file-permissions "file.sh")) ;; => "rwxr-xr-x" (fs/set-posix-file-permissions "file.sh" "rwx------") ;; Owner (str (fs/owner "file.txt")) ;; => "username"
Archives
;; Zip
(fs/zip "archive.zip" ["file1.txt" "dir/file2.txt"])
(fs/zip "archive.zip" ["src"] {:root "src"}) ;; elide "src/" in archive
;; Unzip
(fs/unzip "archive.zip") ;; extract to current dir
(fs/unzip "archive.zip" "dest-dir")
(fs/unzip "archive.zip" "dest-dir" {:replace-existing true})
;; Gzip
(fs/gzip "file.txt") ;; creates file.txt.gz
(fs/gzip "file.txt" {:out-file "archive.gz"})
;; Gunzip
(fs/gunzip "file.txt.gz") ;; extracts to current dir
(fs/gunzip "file.txt.gz" "dest-dir")
Symbolic Links
;; Check (fs/sym-link? "link") ;; => true/false ;; Create (fs/create-sym-link "link" "target") (fs/create-link "hardlink" "existing") ;; hard link ;; Read target (fs/read-link "link") ;; => Path to target
Advanced Patterns
Walking File Trees
;; Low-level tree walker
(fs/walk-file-tree "src"
{:pre-visit-dir (fn [dir attrs]
(println "Entering" dir)
:continue)
:visit-file (fn [file attrs]
(println "File:" file)
:continue)})
;; Find modified files
(fs/modified-since "build/last-build-marker"
(fs/glob "src" "**/*.clj"))
;; => seq of files newer than marker
XDG Directories
;; Standard user directories (fs/xdg-config-home) ;; => ~/.config (fs/xdg-config-home "myapp") ;; => ~/.config/myapp (fs/xdg-data-home) ;; => ~/.local/share (fs/xdg-cache-home) ;; => ~/.cache (fs/xdg-state-home) ;; => ~/.local/state ;; Respects XDG_CONFIG_HOME etc. env vars
Cross-Platform Paths
;; Use forward slashes on all platforms (fs/unixify "C:\\Users\\name\\file.txt") ;; => "C:/Users/name/file.txt" ;; Separators fs/file-separator ;; "/" or "\\" depending on OS fs/path-separator ;; ":" or ";" for PATH-like strings ;; Platform detection (fs/windows?) ;; => true on Windows
Key Gotchas
- •
Empty string means cwd:
(fs/list-dir "")is same as(fs/list-dir "."). Most functions treat""as current directory. - •
Symlink following: Many functions accept
:nofollow-linksor:follow-linksoptions. Default behavior varies:- •Most operations follow symlinks by default
- •Tree walking does NOT follow symlinks unless
:follow-links true - •See README for function-specific defaults
- •
creation-time is unreliable: Behavior varies by OS and Java version. On Linux it often returns modified time. See API notes.
- •
glob patterns use java.nio syntax:
- •
*matches within directory (not across/) - •
**matches across directories - •
{.clj,.cljc}for alternation - •See FileSystem#getPathMatcher
- •
- •
Paths vs Files: Functions return
java.nio.file.Pathobjects. Usestrto convert to string, orfs/fileto convert tojava.io.File. - •
Maps are closed by default in newer glob: Recent versions of fs set
{:hidden false}by default unless pattern starts with.
References
- •Complete API Reference - All functions with detailed docs
- •GitHub: https://github.com/babashka/fs
- •Clojars: https://clojars.org/babashka/fs