@hoge1e3/fs

File System for Browser using localStorage.

Build

npm install
npm run build

Test

npm run test

If "All test Passed." is shown, the test is succeeded.

Example

FS.get method returns a File Object which can access to localStorage.

(See ./example.html)

<script src="path/to/FS.js"></script>
<script>
    var mydir=FS.get("/mydir/");// Directory in localStorage
    var myfile=mydir.rel("myfile.txt");  // File in localStorage (/mydir/myfile.txt)
    myfile.text("my content"); // write file
    console.log(myfile.text()); // read file
    for (let f of mydir.listFiles()) { // list files in mydir
        console.log(f.name());
    }
</script>

Quick Reference of File Object

• File Object can be get by calling FS.get(path).
• In the methods listed below, f and d is a File Object which represents a file and directory respectively. fd can be either file or directory.
• If filepath or filename represents directory, / MUST be present at last of filepath or filename

• f.text(str) write str to the file
• f.text() returns file content of the file in string
• f.obj(o) write object o in JSON to the file
• f.obj() returns the file content as object. The content of the file should be written in JSON
• f.bytes(b) write ArrayBuffer/Buffer(node) to the file
• f.bytes() returns file content as ArrayBuffer(browser)/Buffer(node)
• f.getBytes({binType:ArrayBuffer}) returns file content as ArrayBuffer(both in browser and node)
• d.each(func) iterates over the directory by passing each File Object to func
• d.recursive(func) iterates over all files in the directory and its subdirectory by passing each File Object to func
• d.recursive() returns Generator which iterates over all files in the directory and its subdirectory.
• d.listFiles() returns array of File Objects which represents all files in the directory
• d.ls() returns array of names of all files in the directory
• d.rel(relPath) returns new File Object specified by the relative path
• fd.relPath(base) returns the relative path of the file from the base File Object.
• fd.up() returns new File Object which is parent of the file/directory.
• fd.sibling(name) same as fd.up().rel(name).
• fd.path() returns the full path of the file/directory.
• fd.name() returns the name of the file/directory.
• fd.ext() returns the extention of the file/directory.
• fd.truncExt(e) returns the name removing e (when e is omitted, e equals to fd.ext() )
• f.lastUpdate() return the file's time stamp as the number corrensponding to the value of Date.getTime
• f.rm() removes the file
• d.rm() removes the directory if it is empty.
• d.rm({r:true}) removes the directory and all subfiles/subdirectories.
• fd.exists() checks whether the file/directory exists.
• fd.isDir() checks whether the File Object is directory.
• f.copyFrom(src) copies from src(File Object) to the file.
  • If src is a directory. It is same as cp -R src/* f/* in unix command. NOT cp src/ f/.
• f.copyTo(dst) copies the file to dst(File Object).
  • It is same as cp -R f/* dst/*, NOT cp f/ dst/.
• f.moveFrom(src) moves from src(File Object) to the file.
• f.moveTo(dst) moves the file to dst(File Object).
• d.mkdir() creates the directory.

Use of RAM disk

You can also use RAM disk to store temporal data to memory, that is destroyed when leaving the page.

FS.mount("/tmp/",FS.LSFS.ramDisk());

After that the path beginning with /tmp/ is stored in memory.

Representation of files in localStorage

• The key represents the full path of a file.
• The value represents the file content in string
  • If the file is a binary file, it is stored in data url.
  • Whether the file is binary or text is determined by extension of the file
  • src/MIMETypes.js maps extension to content types. If content type is "text/....", it is regarded as text file
• The key of a directory entry always ends with /
  • The value is a JSON with file list and attributes(lastUpdate).