Implement an Arithmetic Request supporting increment and decrement operations #29
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| @@ -101,6 +101,22 @@ extension ByteBuffer { | |||
| self.writeInteger(UInt8.R) | |||
| } | |||
| } | |||
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| if let arithmeticMode = flags.arithmeticMode { | |||
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I guess you can't specify a storage mode and arithmetic mode. Can we add a precondition somewhere to check for this
| /// - key: The key for the value to increment. | ||
| /// - amount: The `UInt64` amount to increment the value by. | ||
| /// - Throws: A `MemcachedConnectionError` if the connection to the Memcached server is shut down. | ||
| public func increment(_ key: String, amount: UInt64) async throws { |
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Can we use Int here and precondition that it is larger than 0
| /// - key: The key for the value to decrement. | ||
| /// - amount: The `UInt64` amount to decrement the value by. | ||
| /// - Throws: A `MemcachedConnectionError` if the connection to the Memcached server is shut down. | ||
| public func decrement(_ key: String, amount: UInt64) async throws { |
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Same here and adjust the doc comment as well please
| /// Flag 'D' for the 'ma' (meta arithmetic) command. | ||
| /// | ||
| /// Represents the delta to apply to the 'ma' command. The default value is 1. | ||
| var arithmeticDelta: UInt64? |
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Can we make this an associated value of the arithmetic mode enum please
| @@ -33,14 +33,15 @@ extension MemcachedValue where Self: FixedWidthInteger { | |||
| /// | |||
| /// - Parameter buffer: The ByteBuffer to which the integer should be written. | |||
| public func writeToBuffer(_ buffer: inout ByteBuffer) { | |||
| buffer.writeInteger(self) | |||
| buffer.writeString(String(self)) | |||
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This seems wrong. If you want to store an integer we shouldn't convert it to a string. Is this the problem you encountered where you set a key and then want to increment it but the type in memcache was wrong?
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yes, for example when I called set with a value of say 100 the request that was being written looked like ms decrement 8 ... when it should look something like ms decrement 3 ... when I went to increment the value I would get this error CLIENT_ERROR cannot increment or decrement non-numeric value
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we could also make use of writeIntegerAsASCII here.
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So the root problem here is that memcache is operating on the values interpreted as ASCII and not the raw byte values right? So decrement expects that the value for a key is an ASCII string representing an integer?
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Yes that is correct, since the protocol is text based its wanting to receive the values as ASCII strings. we can fall back on making use of writeIntegerAsASCII and then implement one of the possible solutions we outlined here #9 to improve the performance.
dkz2
changed the title
increment and decrement operations
dkz2
changed the title
increment and decrement operations
This PR extends our Memcached functionality by introducing
incrementanddecrementoperations. This addition allows users to perform essential arithmetic task, crucial for diverse caching scenarios and furnishes a more varsity interface.Motivation:
To enhance interactions with Memcached servers, ensuring both versatilely and dynamics. The introduction of
incrementanddecrementoperations address a vital need in caching scenarios, facilitating direct arithmetic adjustments and expanding our API's capabilities.Modifications:
ArithmeticCommandto ourMemcachedRequeststruct enablingarithmeticoperations in upcoming requests.MemcachedRequestEncoderto handlearithmeticoperation request.MemcachedConnectionnow boastsincrementanddecrementmethods, providing developers with a straightforward way to interact with the Memcached server forarithmeticprocesses.ArithmeticModeenum to clearly differential betweenincrementanddecrementoperations.arithmeticDeltaproperty toMemcachedFlagswhich designates the magnitude by which a value should be incremented or decremented.Results:
With the addition of the
incrementanddecrementoperation support, our API now allows users to directly manipulate numerical values stored within Memcached servers. This fosters more dynamic caching strategies and enhances overall data management efficiency.