mirror of https://bitbucket.org/ausocean/av.git
93 lines
2.0 KiB
Go
93 lines
2.0 KiB
Go
/*
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NAME
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meta.go
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DESCRIPTION
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See Readme.md
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AUTHOR
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Saxon Nelson-Milton <saxon@ausocean.org>
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LICENSE
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meta.go is Copyright (C) 2017-2019 the Australian Ocean Lab (AusOcean)
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It is free software: you can redistribute it and/or modify them
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under the terms of the GNU General Public License as published by the
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Free Software Foundation, either version 3 of the License, or (at your
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option) any later version.
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It is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with revid in gpl.txt. If not, see http://www.gnu.org/licenses.
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*/
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package mts
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import (
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"errors"
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"sync"
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)
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var (
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errKeyAbsent = errors.New("Key does not exist in map")
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)
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type Meta struct {
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mu sync.RWMutex
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data map[string]string
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}
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func NewMeta() *Meta {
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return &Meta{data: make(map[string]string)}
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}
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// Add adds metadata with key and val, if already exists return error
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func (m *Meta) Add(key, val string) {
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m.mu.Lock()
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m.data[key] = val
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m.mu.Unlock()
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}
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// All returns the a copy of the map containing the meta data
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func (m *Meta) All() map[string]string {
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m.mu.Lock()
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cpy := make(map[string]string)
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for k, v := range m.data {
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cpy[k] = v
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}
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m.mu.Unlock()
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return cpy
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}
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// Get returns the meta data for the passed key
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func (m *Meta) Get(key string) (string, error) {
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m.mu.Lock()
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val, ok := m.data[key]
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m.mu.Unlock()
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if !ok {
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return "", errKeyAbsent
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}
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return val, nil
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}
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// Remove deletes a meta entry in the map and returns error if it doesn’t exist
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func (m *Meta) Delete(key string) error {
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m.mu.Lock()
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defer m.mu.Unlock()
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if _, ok := m.data[key]; ok {
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delete(m.data, key)
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return nil
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}
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return errors.New("Trying to delete map entry that doesn't exist")
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}
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func (m *Meta) Encode() []byte {
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// TODO: complete this
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return []byte("someData")
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}
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