Synchronise access to shared table info dictionary
#101
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kilnerm
changed the title
table info dictionary
djones6
suggested changes
Feb 11, 2019
| @@ -26,7 +26,7 @@ import Dispatch | |||
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| public class TableInfo { | |||
| private var codableMap = [String: (info: TypeInfo, table: Table)]() | |||
| private var codableMapLock = DispatchSemaphore(value: 1) | |||
| private var codableMapQueue = DispatchQueue(label: "codaleMap.queue", attributes: .concurrent) | |||
| return result | ||
| var decodeError: Error? | ||
| // Prevent concurrent access to codableMap while writing | ||
| do { |
There was a problem hiding this comment.
Is it necessary to capture decodeError? If you take the do/catch away, the error will be thrown out of queue.sync and this function will exit early (throwing). The logic that follows could then be simplified to:
guard let decodeResult = result else {
throw RequestError...
}
return decodeResult
| @@ -35,18 +35,33 @@ public class TableInfo { | |||
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| func getInfo<T: Decodable>(_ idColumn: (name: String, type: SQLDataType.Type), _ tableName: String, _ type: T.Type) throws -> (info: TypeInfo, table: Table) { | |||
| let typeString = "\(type)" | |||
| if let result = codableMap[typeString] { | |||
| var result: (TypeInfo, Table)? = nil | |||
| // Read from codableMap when no concurrent write is occuring | |||
djones6
approved these changes
Feb 12, 2019
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This PR adds synchronization around access to the dictionary used to store table info.
Without this synchronization concurrent access can lead to crashes on Swift 5.