44 lines
958 B
Go
44 lines
958 B
Go
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package cache
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import (
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"os"
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)
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// diskReader reads a file from the cache on disk.
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type diskReader struct {
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entry *Entry
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file *os.File
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}
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// newDiskReader creates a reader from the provided JSON and data filenames.
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// Failure to open either of these results in an immediate error.
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func newDiskReader(jsonFilename, dataFilename string) (*diskReader, error) {
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e := &Entry{}
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if err := e.Load(jsonFilename); err != nil {
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return nil, err
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}
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f, err := os.Open(dataFilename)
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if err != nil {
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return nil, err
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}
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return &diskReader{
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entry: e,
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file: f,
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}, nil
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}
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// Read attempts to read as much data as possible into the provided buffer.
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func (d *diskReader) Read(p []byte) (int, error) {
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return d.file.Read(p)
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}
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// Close attempts to close the data file.
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func (d *diskReader) Close() error {
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return d.file.Close()
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}
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// GetEntry returns the Entry associated with the file.
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func (d *diskReader) GetEntry() (*Entry, error) {
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return d.entry, nil
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}
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