47 lines
1.1 KiB
Go
47 lines
1.1 KiB
Go
package wisski
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import (
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"errors"
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"github.com/FAU-CDI/wisski-distillery/internal/models"
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)
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var ErrLocked = errors.New("instance is locked")
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// TryLock attemps to lock this WissKI
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// If this is not possible, returns ErrLocked
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func (wisski *WissKI) TryLock() error {
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table, err := wisski.SQL.QueryTable(true, models.LockTable)
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if err != nil {
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return ErrLocked
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}
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result := table.FirstOrCreate(&models.Lock{}, models.Lock{Slug: wisski.Slug})
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locked := result.Error == nil && result.RowsAffected == 1
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if !locked {
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return ErrLocked
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}
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return nil
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}
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func (wisski *WissKI) IsLocked() (locked bool) {
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table, err := wisski.SQL.QueryTable(true, models.LockTable)
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if err != nil {
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return false
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}
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// check if this instance is locked
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table.Select("count(*) > 0").Where("slug = ?", wisski.Slug).Find(&locked)
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return
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}
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// Unlock unlocks this WissKI instance and returns if it succeeded
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func (wisski WissKI) Unlock() bool {
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table, err := wisski.SQL.QueryTable(true, models.LockTable)
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if err != nil {
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return false
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}
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result := table.Where("slug = ?", wisski.Slug).Delete(&models.Lock{})
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return result.Error == nil && result.RowsAffected == 1
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}
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