Documentation
¶
Overview ¶
Package lazyloader provides lazy loading functionality for documents
This package implements lazy loading of documents to optimize memory usage by loading content only when needed. It also provides memory management capabilities to control the total memory used by loaded documents.
Example:
// Create a lazy document
doc := lazyloader.NewLazyDocument("path/to/document.pdf")
// Load content on demand
content, err := doc.Load()
if err != nil {
log.Fatal(err)
}
// Use content...
// Unload to free memory
doc.Unload()
// Create a document manager with memory limit
manager := lazyloader.NewLazyDocumentManager(100 * 1024 * 1024) // 100MB
doc := manager.AddDocument("path/to/document.pdf")
content, err := manager.LoadDocument("path/to/document.pdf")
Index ¶
- type LazyDocument
- func (d *LazyDocument) IsLoaded() bool
- func (d *LazyDocument) Load() ([]byte, error)
- func (d *LazyDocument) LoadWithContext(ctx context.Context) ([]byte, error)
- func (d *LazyDocument) Path() string
- func (d *LazyDocument) Reader() (io.Reader, error)
- func (d *LazyDocument) Size() (int64, error)
- func (d *LazyDocument) Unload()
- type LazyDocumentManager
- func (m *LazyDocumentManager) AddDocument(path string) *LazyDocument
- func (m *LazyDocumentManager) GetDocument(path string) (*LazyDocument, bool)
- func (m *LazyDocumentManager) GetMemoryUsage() int64
- func (m *LazyDocumentManager) LoadDocument(path string) ([]byte, error)
- func (m *LazyDocumentManager) RemoveDocument(path string)
- func (m *LazyDocumentManager) UnloadAll()
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type LazyDocument ¶
type LazyDocument struct {
// contains filtered or unexported fields
}
LazyDocument represents a document that is loaded on demand
A LazyDocument loads its content only when needed, which helps optimize memory usage by avoiding loading large documents until they are actually required.
Example:
// Create a lazy document from a file
doc := NewLazyDocument("path/to/document.pdf")
// Check if loaded
fmt.Println("Is loaded:", doc.IsLoaded()) // false
// Load content on demand
content, err := doc.Load()
if err != nil {
log.Fatal(err)
}
// Check size
size, err := doc.Size()
if err != nil {
log.Fatal(err)
}
fmt.Printf("Document size: %d bytes\n", size)
// Unload to free memory
doc.Unload()
fmt.Println("Is loaded:", doc.IsLoaded()) // false
func NewLazyDocument ¶
func NewLazyDocument(path string) *LazyDocument
NewLazyDocument creates a new lazy document
Parameters: - path: Path to the document file
Returns: - *LazyDocument: New lazy document instance
func NewLazyDocumentWithLoader ¶
func NewLazyDocumentWithLoader(path string, loader func() ([]byte, error)) *LazyDocument
NewLazyDocumentWithLoader creates a new lazy document with a custom loader
Parameters: - path: Path to the document - loader: Custom loader function
Returns: - *LazyDocument: New lazy document instance
func (*LazyDocument) IsLoaded ¶
func (d *LazyDocument) IsLoaded() bool
IsLoaded returns whether the document is loaded
Returns: - bool: True if the document is loaded
func (*LazyDocument) Load ¶
func (d *LazyDocument) Load() ([]byte, error)
Load loads the document content
This method loads the document content if it's not already loaded. It uses double-checked locking to ensure thread safety.
Returns: - []byte: Document content - error: Error if loading fails
func (*LazyDocument) LoadWithContext ¶
func (d *LazyDocument) LoadWithContext(ctx context.Context) ([]byte, error)
LoadWithContext loads the document with context cancellation
This method loads the document content with support for context cancellation.
Parameters: - ctx: Context for cancellation
Returns: - []byte: Document content - error: Error if loading fails or context is cancelled
func (*LazyDocument) Path ¶
func (d *LazyDocument) Path() string
Path returns the document path
Returns: - string: Document path
func (*LazyDocument) Reader ¶
func (d *LazyDocument) Reader() (io.Reader, error)
Reader returns an io.Reader for the document
This method returns an io.Reader for the document content, loading the content if it's not already loaded.
Returns: - io.Reader: Reader for the document content - error: Error if loading fails
func (*LazyDocument) Size ¶
func (d *LazyDocument) Size() (int64, error)
Size returns the document size (requires loading metadata)
Returns: - int64: Document size in bytes - error: Error if metadata loading fails
func (*LazyDocument) Unload ¶
func (d *LazyDocument) Unload()
Unload unloads the document content to free memory
This method unloads the document content and resets the loaded flag, freeing up memory occupied by the document.
type LazyDocumentManager ¶
type LazyDocumentManager struct {
// contains filtered or unexported fields
}
LazyDocumentManager manages multiple lazy documents
The LazyDocumentManager manages a collection of lazy documents and tracks memory usage to ensure it stays within the specified limit. It automatically evicts documents when memory usage exceeds the limit.
Example:
// Create a document manager with 100MB memory limit
manager := NewLazyDocumentManager(100 * 1024 * 1024)
// Add documents
doc1 := manager.AddDocument("doc1.pdf")
doc2 := manager.AddDocument("doc2.pdf")
// Load documents
content1, err := manager.LoadDocument("doc1.pdf")
if err != nil {
log.Fatal(err)
}
// Check memory usage
fmt.Printf("Memory usage: %d bytes\n", manager.GetMemoryUsage())
// Unload all documents
manager.UnloadAll()
fmt.Printf("Memory usage after unload: %d bytes\n", manager.GetMemoryUsage())
func NewLazyDocumentManager ¶
func NewLazyDocumentManager(maxSize int64) *LazyDocumentManager
NewLazyDocumentManager creates a new lazy document manager
Parameters: - maxSize: Maximum memory usage in bytes
Returns: - *LazyDocumentManager: New lazy document manager instance
func (*LazyDocumentManager) AddDocument ¶
func (m *LazyDocumentManager) AddDocument(path string) *LazyDocument
AddDocument adds a document to the manager
This method adds a document to the manager. If the document already exists, it returns the existing document.
Parameters: - path: Path to the document file
Returns: - *LazyDocument: Lazy document instance
func (*LazyDocumentManager) GetDocument ¶
func (m *LazyDocumentManager) GetDocument(path string) (*LazyDocument, bool)
GetDocument gets a document from the manager
Parameters: - path: Path to the document file
Returns: - *LazyDocument: Lazy document instance - bool: True if the document exists
func (*LazyDocumentManager) GetMemoryUsage ¶
func (m *LazyDocumentManager) GetMemoryUsage() int64
GetMemoryUsage returns the current memory usage
Returns: - int64: Current memory usage in bytes
func (*LazyDocumentManager) LoadDocument ¶
func (m *LazyDocumentManager) LoadDocument(path string) ([]byte, error)
LoadDocument loads a document and tracks memory usage
This method loads a document and tracks memory usage. If loading the document would exceed the memory limit, it evicts existing documents to make room.
Parameters: - path: Path to the document file
Returns: - []byte: Document content - error: Error if loading fails or memory limit is exceeded
func (*LazyDocumentManager) RemoveDocument ¶
func (m *LazyDocumentManager) RemoveDocument(path string)
RemoveDocument removes a document from the manager
This method removes a document from the manager and updates the memory usage if the document was loaded.
Parameters: - path: Path to the document file
func (*LazyDocumentManager) UnloadAll ¶
func (m *LazyDocumentManager) UnloadAll()
UnloadAll unloads all documents
This method unloads all documents managed by the manager, freeing up all memory used by loaded documents.
Source Files