[Client] add swift client

clients/swift/README.md

@@ -0,0 +1,21 @@
+## CAC and Experimentation clients in `Swift`
+
+- ## Walkthrough
+    - Create bridging file for each module
+    - add the `#include` statement for the C header file
+    - without xcode: use `swiftc` to compile modules using `-L`, `-l` and `-import-objc-header` flags to specify object files search dir, object-module name and bridging file path respectively. (checkout : [default.nix](default.nix))
+    - with xcode: todo!
+
+- ## setup (nix) :
+    `nix develop .#swift`
+
+- ## run without xcode (using nix) :
+    1. to compile cac client: `compileCac`
+    2. to compile exp client: `compileExp`
+    3. use generated bins
+
+- ## run using xcode :
+    todo!
+
+- ## run example :
+    todo!

clients/swift/cac/Bridging-Header.h

@@ -0,0 +1,6 @@
+#ifndef CAC_Bridging_Header_h
+#define CAC_Bridging_Header_h
+
+#include "../../../headers/libcac_client.h"
+
+#endif /* CAC_Bridging_Header_h */

clients/swift/cac/main.swift

@@ -0,0 +1,93 @@
+import Foundation
+
+typealias UnknownClientPointer = OpaquePointer
+typealias Value = [String: Any]
+
+enum MergeStrategy {
+    case MERGE
+    case REPLACE
+
+    var show: String {
+        switch self {
+        case .MERGE:
+            return "MERGE"
+        case .REPLACE:
+            return "REPLACE"
+        }
+    }
+}
+
+func createCacClient(tenant: String, frequency: UInt, hostname: String) -> Bool {
+    return tenant.withCString { t -> Bool in
+        return hostname.withCString { h -> Bool in
+            let resp = cac_new_client(t, frequency, h);
+            if (resp == 0) {
+                return true
+            }
+            return false
+        }
+    }
+}
+
+func getCacClient(tenant: String) -> UnknownClientPointer? {
+    return tenant.withCString { t -> UnknownClientPointer? in
+        return cac_get_client(tenant)
+    }
+}
+
+func cacStartPolling(tenant: String) {
+    tenant.withCString { t in
+        cac_start_polling_update(t)
+    }
+}
+
+func getCacLastModified(client: UnknownClientPointer) -> String? {
+    let resp = cac_get_last_modified(client)
+    return resp.map { String(cString: $0) }
+}
+
+func parseJson(jsonString: String) -> Value? {
+    if let jsonData = jsonString.data(using: .utf8) {
+        do {
+            return try JSONSerialization.jsonObject(with: jsonData, options: []) as? Value
+        } catch {
+            return nil
+        }
+    }
+    return nil
+}
+
+func getResolvedConfig(client: UnknownClientPointer, context: String, filterKeys: [String]? = nil) -> Value? {
+    let keys = filterKeys.map { $0.joined(separator: "|") }
+
+    return context.withCString { c -> Value? in
+        return MergeStrategy.MERGE.show.withCString { m -> Value? in
+            let rawData : UnsafePointer<CChar>?
+            if let k = keys {
+                rawData = k.withCString { ck -> UnsafePointer<CChar>? in
+                    return cac_get_resolved_config(client, c, ck, m)
+                }
+            } else {
+                rawData = cac_get_resolved_config(client, c, nil, m)
+            }
+            return rawData.map { String(cString: $0) }.flatMap { parseJson(jsonString: $0) }
+        }
+    }
+}
+
+func getDefaultConfig(client: UnknownClientPointer, filterKeys: [String]) -> Value? {
+    let keys = filterKeys.joined(separator: "|")
+
+    return keys.withCString { k -> Value? in
+        let rawData = cac_get_default_config(client, keys)
+        return rawData.map { String(cString: $0) }.flatMap { parseJson(jsonString: $0) }
+    }
+}
+
+func cacFreeClient(client: UnknownClientPointer) {
+    cac_free_client(client)
+}
+
+func cacLastErrorMessage() -> String? {
+    return cac_last_error_message().map { String(cString: $0) }
+}

clients/swift/default.nix

@@ -0,0 +1,21 @@
+{
+  perSystem = { config, pkgs, self', lib, ... }: {
+    devShells.swift = let
+        compileCac = pkgs.writeShellScriptBin "compileCac" ''
+            swiftc cac/main.swift -L../../target/debug -lcac_client -import-objc-header cac/Bridging-Header.h -o cac-swift
+        '';
+        compileExp = pkgs.writeShellScriptBin "compileExp" ''
+            swiftc exp/main.swift example/exp_example.swift -L../../target/debug -lexperimentation_client -import-objc-header exp/Bridging-Header.h -o exp-swift
+        '';
+    in
+    pkgs.mkShell {
+        name = "superposition-swift-clients";
+        buildInputs = with pkgs; [
+            swift
+            swiftPackages.Foundation
+            compileCac
+            compileExp
+        ];
+    };
+  };
+}

clients/swift/example/cac_example.swift

@@ -0,0 +1,41 @@
+import Foundation
+
+func main() {
+    let t = "test"
+    let f : UInt = 300
+    let h = "http://localhost:8080"
+
+    if (createCacClient(tenant: t, frequency: f, hostname: h)) {
+        print("createCacClient success!")
+
+        if let client = getCacClient(tenant: t) {
+            print("getCacClient success!")
+
+            let thread = Thread {
+                cacStartPolling(tenant: t)
+            }
+            thread.start()
+            print("cacStartPolling: thread started!")
+
+            let m = getCacLastModified(client: client)
+            let r = getResolvedConfig(client: client, context: "{}")
+            let d = getDefaultConfig(client: client, filterKeys: [])
+
+            print("Last Modified: \(m)")
+            print("Resolved Config: \(r)")
+            print("Default Config: \(d)")
+
+            thread.cancel()
+            print("cacStartPolling: thread closed!")
+
+            cacFreeClient(client: client)
+            print("Free client memory!")
+        } else {
+            print("getCacClient failed!")
+        }
+    } else {
+        print("createCacClient failed!")
+    }
+}
+
+main()

clients/swift/example/exp_example.swift

@@ -0,0 +1,39 @@
+import Foundation
+
+func main() {
+    let t = "test"
+    let f : UInt = 300
+    let h = "http://localhost:8080"
+
+    if (createExptClient(tenant: t, frequency: f, hostname: h)) {
+        print("createExptClient successs!")
+        if let client = getExptClient(tenant: t) {
+            print("getExptClient successs!")
+
+            let thread = Thread {
+                exptStartPolling(tenant: t)
+            }
+            thread.start()
+            print("cacStartPolling: thread started!")
+
+            let m = getApplicableVariant(client: client, context: "{}", toss: 1)
+            let r = getSatisfiedExperiments(client: client, context: "{}", filterPrefix: [])
+            let d = getRunningExperiments(client: client)
+            let v = getFilteredSatisfiedExperiments(client: client, context: "{}", filterPrefix: [])
+            print("Applicable Variants: \(r)")
+            print("Satisfied Experiments: \(m)")
+            print("Running Experiments: \(d)")
+            print("Filtered Satisfied Experiments: \(v)")
+
+            thread.cancel()
+            print("cacStartPolling: thread closed!")
+
+            exptFreeClient(client: client)
+            print("Free client memory!")
+        } else {
+            print("getExptClient failed!")
+        }
+    } else {
+        print("createExptClient failed!")
+    }
+}

clients/swift/exp/Bridging-Header.h

@@ -0,0 +1,6 @@
+#ifndef Experimentation_Bridging_Header_h
+#define Experimentation_Bridging_Header_h
+
+#include "../../../headers/libexperimentation_client.h"
+
+#endif /* Experimentation_Bridging_Header_h */

clients/swift/exp/main.swift

@@ -0,0 +1,81 @@
+import Foundation
+
+typealias UnknownClientPointer = OpaquePointer
+typealias Value = [String: Any]
+
+func createExptClient(tenant: String, frequency: UInt, hostname: String) -> Bool {
+    return tenant.withCString { t -> Bool in
+        return hostname.withCString { h -> Bool in
+            let resp = expt_new_client(t, frequency, h);
+            if (resp == 0) {
+                return true
+            }
+            return false
+        }
+    }
+}
+
+func getExptClient(tenant: String) -> UnknownClientPointer? {
+    return tenant.withCString { t -> UnknownClientPointer? in
+        return expt_get_client(tenant)
+    }
+}
+
+func exptStartPolling(tenant: String) {
+    tenant.withCString { t in
+        expt_start_polling_update(t)
+    }
+}
+
+func parseJson(jsonString: String) -> Value? {
+    if let jsonData = jsonString.data(using: .utf8) {
+        do {
+            return try JSONSerialization.jsonObject(with: jsonData, options: []) as? [String: Any]
+        } catch {
+            return nil
+        }
+    }
+    return nil
+}
+
+func getApplicableVariant(client: UnknownClientPointer, context: String, toss: Int16) -> Value? {
+    return context.withCString { c -> Value? in
+        let rawData = expt_get_applicable_variant(client, c, toss)
+        return rawData.map { String(cString: $0) }.flatMap { parseJson(jsonString: $0) }
+    }
+}
+
+func getSatisfiedExperiments(client: UnknownClientPointer, context: String, filterPrefix: [String]) -> Value? {
+    let keys = filterPrefix.joined(separator: "|")
+
+    return keys.withCString { k -> Value? in
+        return context.withCString { c -> Value? in
+            let rawData = expt_get_satisfied_experiments(client, c, k)
+            return rawData.map { String(cString: $0) }.flatMap { parseJson(jsonString: $0) }
+        }
+    }
+}
+
+func getRunningExperiments(client: UnknownClientPointer) -> Value? {
+    let resp = expt_get_running_experiments(client)
+    return resp.map { String(cString: $0) }.flatMap { parseJson(jsonString: $0) }
+}
+
+
+func getFilteredSatisfiedExperiments(client: UnknownClientPointer, context: String, filterPrefix: [String]) -> Value? {
+    let keys = filterPrefix.joined(separator: "|")
+    return context.withCString { c -> Value? in
+        return keys.withCString { k -> Value? in
+            let resp = expt_get_filtered_satisfied_experiments(client, c, k)
+            return resp.map { String(cString: $0) }.flatMap { parseJson(jsonString: $0) }
+        }
+    }
+}
+
+func exptFreeClient(client: UnknownClientPointer) {
+    expt_free_client(client)
+}
+
+func exptLastErrorMessage() -> String? {
+    return expt_last_error_message().map { String(cString: $0) }
+}

flake.nix

@@ -21,6 +21,7 @@
         ./nix/pre-commit.nix
         ./clients/haskell
         ./nix/rust.nix
+        ./clients/swift
       ];
 
       perSystem = { pkgs, self', config, ... }: {