Package mem - in-memory backend VFS implementation.
Rely on github.com/c2fo/vfs/v6/backend
import(
"github.com/c2fo/vfs/v6/backend"
"github.com/c2fo/vfs/v6/backend/mem"
)
func UseFs() error {
fs := backend.Backend(mem.Scheme)
...
}Or call directly:
import _mem "github.com/c2fo/vfs/v6/backend/mem"
func DoSomething() {
fs := _mem.NewFileSystem()
...
}const Scheme = "mem"Scheme defines the FileSystem type's underlying implementation.
type File struct {
}File implements vfs.File interface for the in-memory implementation of FileSystem. A file struct holds a pointer to a single memFile. Multiple threads will refer to the same memFile. Simultaneous reading is allowed, but writing and closing are protected by locks.
func (f *File) Close() errorClose imitates io.Closer by resetting the cursor and setting a boolean
func (f *File) CopyToFile(target vfs.File) errorCopyToFile copies the receiver file into the target file. The target file is deleted, so any references to it will be nil. In order to access the target after calling CopyToFile use its previous path to call it using the fsMap. Additionally, after this is called, f's cursor will reset as if it had been closed.
func (f *File) CopyToLocation(location vfs.Location) (vfs.File, error)CopyToLocation copies the current file to the given location. If file exists at given location contents are simply overwritten using "CopyToFile", otherwise a newFile is made, takes the contents of the current file, and ends up at the given location
func (f *File) Delete() errorDelete removes the file from the FileSystem. Sets it path in the fsMap to nil, and also nils the file's members
func (f *File) Exists() (bool, error)Exists returns whether or not a file exists. Creating a file does not guarantee its existence, but creating one and writing to it does
func (f *File) LastModified() (*time.Time, error)LastModified simply returns the file's lastModified, if the file exists
func (f *File) Location() vfs.LocationLocation simply returns the file's underlying location struct pointer
func (f *File) MoveToFile(file vfs.File) errorMoveToFile creates a newFile, and moves it to "file". The receiver is always deleted (since it's being "moved")
func (f *File) MoveToLocation(location vfs.Location) (vfs.File, error)MoveToLocation moves the receiver file to the passed in location. It does so by creating a copy of 'f' in "location". 'f' is subsequently deleted
func (f *File) Name() stringName returns the basename of the file
func (f *File) Path() stringPath returns the absolute path to the file
func (f *File) Read(p []byte) (n int, err error)Read implements the io.Reader interface. Returns number of bytes read and potential errors
func (f *File) Seek(offset int64, whence int) (int64, error)Seek implements the io.Seeker interface. Returns the current position of the cursor and errors if any
func (f *File) Size() (uint64, error)Size returns the size of the file contents. In our case, the length of the file's byte slice
func (f *File) String() stringString implements the io.Stringer interface. It returns a string representation of the file's URI
func (f *File) Touch() errorTouch takes an in-memory vfs.File, makes it existent, and updates the lastModified
func (f *File) URI() stringURI returns the file's URI, if it exists
func (f *File) Write(p []byte) (int, error)Write implements the io.Writer interface. Returns number of bytes written and any errors
type FileSystem struct {
sync.Mutex
}FileSystem implements vfs.FileSystem for an in-memory file system.
func NewFileSystem() *FileSystemNewFileSystem is used to initialize the file system struct for an in-memory FileSystem.
func (fs *FileSystem) Name() stringName returns the name of the underlying FileSystem
func (fs *FileSystem) NewFile(volume string, absFilePath string, opts ...options.NewFileOption) (vfs.File, error)NewFile function returns the in-memory implementation of vfs.File. Since this is inside FileSystem, we assume that the caller knows that the CWD is the root. If a non-absolute path is given, an error is thrown. Additionally, a file does not technically exist until a call to "Touch()" is made on it. The "Touch" call links the file with FileSystem's map and brings it into existence. If a file is written to before a touch call, Write() will take care of that call. This is true for other functions as well and existence only poses a problem in the context of deletion or copying FROM a non-existent file.
func (fs *FileSystem) NewLocation(volume string, absLocPath string) (vfs.Location, error)NewLocation function returns the in-memory implementation of vfs.Location. A location always exists. If a file is created on a location that has not yet been made in the fsMap, then the location will be created with the file
func (fs *FileSystem) Retry() vfs.RetryRetry will return a retrier provided via options, or a no-op if none is provided.
func (fs *FileSystem) Scheme() stringScheme returns the scheme of the underlying FileSystem
type Location struct {
}Location implements the vfs.Location interface specific to in-memory FileSystem.
func (l *Location) ChangeDir(relLocPath string) errorChangeDir simply changes the directory of the location
func (l *Location) DeleteFile(relFilePath string) errorDeleteFile locates the file given the fileName and calls delete on it
func (l *Location) Exists() (bool, error)Exists always returns true on locations
func (l *Location) FileSystem() vfs.FileSystemFileSystem returns the type of file system location exists on, if it exists at all
func (l *Location) List() ([]string, error)List finds all of the files living at the current location and returns them in a slice of strings. If there are no files at location, then an empty slice will be returned
func (l *Location) ListByPrefix(prefix string) ([]string, error)ListByPrefix tags a prefix onto the current path and in a slice, returns all file base names whose full paths contain that substring Returns empty slice if nothing found
func (l *Location) ListByRegex(regex *regexp.Regexp) ([]string, error)ListByRegex takes a regular expression and returns a slice of strings containing the base names of files found that matched the regular expression. Returns an empty slice upon nothing found
func (l *Location) NewFile(relFilePath string, opts ...options.NewFileOption) (vfs.File, error)NewFile creates a vfs.File given its relative path and tags it onto "l's" path
func (l *Location) NewLocation(relLocPath string) (vfs.Location, error)NewLocation creates a new location at the given relative path, which is tagged onto the current locations absolute path
func (l *Location) Path() stringPath returns the full, absolute path of the location with leading and trailing slashes
func (l *Location) String() stringString implements io.Stringer by returning the location's URI as a string
func (l *Location) URI() stringURI returns the URI of the location if the location exists
func (l *Location) Volume() stringVolume returns the volume of the current FileSystem.