Add stream option

README.md

@@ -76,17 +76,24 @@ cli {
 ```
 (Hint: if file extension is not assigned to any installed program, it will throw a `System.NullReferenceException`)
 
-Write output to a specific file:
+Write output or stream to a specific file:
 ```fsharp
 cli {
     Exec "dotnet"
     Arguments "--list-sdks"
     Output @"absolute\path\to\dotnet-sdks.txt"
 }
 |> Command.execute
+
+cli {
+    Exec "dotnet"
+    Arguments "--list-sdks"
+    Stream @"absolute\path\to\dotnet-sdks.txt"
+}
+|> Command.execute
 ```
 
-Write output to a function (logging, printing, etc.):
+Write output or stream to a function (logging, printing, etc.):
 ```fsharp
 let log (output: string) = Debug.Log($"CLI log: {output}")
 
@@ -96,6 +103,13 @@ cli {
     Output log
 }
 |> Command.execute
+
+cli {
+    Exec "dotnet"
+    Arguments "--list-sdks"
+    Stream log
+}
+|> Command.execute
 ```
 
 Add environment variables for the executing program:

src/Fli.Tests/ShellContext/ShellCommandExecuteWindowsTests.fs

@@ -82,6 +82,21 @@ let ``Get output in StringBuilder`` () =
 
     sb.ToString() |> should equal "Test\r\n"
 
+[<Test>]
+[<Platform("Win")>]
+let ``Get stream in StringBuilder`` () =
+    let sb = StringBuilder()
+
+    cli {
+        Shell CMD
+        Command "echo Test"
+        Stream sb
+    }
+    |> Command.execute
+    |> ignore
+
+    sb.ToString() |> should equal "Test"
+
 [<Test>]
 [<Platform("Win")>]
 let ``CMD returning non zero process id`` () =

src/Fli/CE.fs

@@ -55,6 +55,25 @@ module CE =
         member _.Output(context: ICommandContext<ShellContext>, func: string -> unit) =
             Cli.output (Custom func) context.Context
 
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ShellContext>, output: Outputs) = Cli.stream output context.Context
+
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ShellContext>, filePath: string) =
+            Cli.stream (File filePath) context.Context
+
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ShellContext>, stringBuilder: StringBuilder) =
+            Cli.stream (StringBuilder stringBuilder) context.Context
+
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Strem(context: ICommandContext<ShellContext>, func: string -> unit) =
+            Cli.stream (Custom func) context.Context
+
         /// Current executing `working directory`.
         [<CustomOperation("WorkingDirectory")>]
         member _.WorkingDirectory(context: ICommandContext<ShellContext>, workingDirectory) =
@@ -127,6 +146,24 @@ module CE =
         member _.Output(context: ICommandContext<ExecContext>, func: string -> unit) =
             Program.output (Custom func) context.Context
 
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ExecContext>, output: Outputs) = Program.stream output context.Context
+
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ExecContext>, filePath: string) =
+            Program.stream (File filePath) context.Context
+
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ExecContext>, stringBuilder: StringBuilder) =
+            Program.stream (StringBuilder stringBuilder) context.Context
+
+        /// Extra `Output` that is being executed immediately after getting output from execution.
+        [<CustomOperation("Stream")>]
+        member _.Stream(context: ICommandContext<ExecContext>, func: string -> unit) =
+            Program.stream (Custom func) context.Context
+
         /// Current executing `working directory`.
         [<CustomOperation("WorkingDirectory")>]
         member _.WorkingDirectory(context: ICommandContext<ExecContext>, workingDirectory) =

src/Fli/Command.fs

@@ -109,22 +109,27 @@ module Command =
         |> Async.AwaitTask
 #endif
 
-    let private startProcess (inputFunc: Process -> unit) (outputFunc: string -> unit) psi =
+    let private startProcess (inputFunc: Process -> unit) (outputFunc: string -> unit) (streamFunc: string -> unit) (isNotStreaming: bool) psi =
         let proc = Process.Start(startInfo = psi)
         proc |> inputFunc
 
-        let text =
-            if psi.UseShellExecute |> not then
+        let mutable text =
+            if psi.UseShellExecute |> not && isNotStreaming then
                 proc.StandardOutput.ReadToEnd()
             else
+                proc.BeginOutputReadLine()
                 ""
 
-        let error =
-            if psi.UseShellExecute |> not then
+        let mutable error =
+            if psi.UseShellExecute |> not && isNotStreaming then
                 proc.StandardError.ReadToEnd()
             else
+                proc.BeginErrorReadLine()
                 ""
 
+        proc.OutputDataReceived.Add(fun args -> text <- text + args.Data ; streamFunc args.Data)
+        proc.ErrorDataReceived.Add(fun args -> error <- error + args.Data ; streamFunc args.Data)
+
         proc.WaitForExit()
 
         text |> outputFunc
@@ -201,6 +206,15 @@ module Command =
             | Outputs.Custom(func) -> func.Invoke(output)
         | None -> ()
 
+    let private streamOutput (outputType: Outputs option) (output: string): unit =
+        match outputType with
+        | Some(o) ->
+            match o with
+            | Outputs.File(file) -> File.AppendAllText(file, output)
+            | Outputs.StringBuilder(stringBuilder) -> output |> stringBuilder.Append |> ignore
+            | Outputs.Custom(func) -> func.Invoke(output)
+        | None -> ()
+
     let private setupCancellationToken (cancelAfter: int option) =
         let cts = new CancellationTokenSource()
 
@@ -278,6 +292,8 @@ module Command =
             |> startProcess
                 (writeInput context.config.Input context.config.Encoding)
                 (writeOutput context.config.Output)
+                (streamOutput context.config.Stream)
+                (context.config.Stream.IsNone)
 
         /// Executes the given context as a new process.
         static member execute(context: ExecContext) =
@@ -286,6 +302,8 @@ module Command =
             |> startProcess
                 (writeInput context.config.Input context.config.Encoding)
                 (writeOutput context.config.Output)
+                (streamOutput context.config.Stream)
+                (context.config.Stream.IsNone)
 
 #if NET
         /// Executes the given context as a new process asynchronously.

src/Fli/Domain.fs

@@ -14,6 +14,7 @@ module Domain =
           Command: string option
           Input: string option
           Output: Outputs option
+          Stream: Outputs option
           WorkingDirectory: string option
           EnvironmentVariables: (string * string) list option
           Encoding: Encoding option
@@ -46,6 +47,7 @@ module Domain =
           Arguments: Arguments option
           Input: string option
           Output: Outputs option
+          Stream: Outputs option
           WorkingDirectory: string option
           Verb: string option
           UserName: string option
@@ -96,6 +98,7 @@ module Domain =
               Command = None
               Input = None
               Output = None
+              Stream = None
               WorkingDirectory = None
               EnvironmentVariables = None
               Encoding = None
@@ -106,6 +109,7 @@ module Domain =
               Arguments = None
               Input = None
               Output = None
+              Stream = None
               WorkingDirectory = None
               Verb = None
               UserName = None

src/Fli/Dsl.fs

@@ -27,6 +27,15 @@ module Cli =
         { context with
             config.Output = outputsOption }
 
+    let stream (output: Outputs) (context: ShellContext) =
+        let outputsOption =
+            match output with
+            | File path -> path |> toOptionWithDefault output
+            | _ -> Some output
+
+        { context with
+            config.Stream = outputsOption }
+
     let workingDirectory (workingDirectory: string) (context: ShellContext) =
         { context with
             config.WorkingDirectory = Some workingDirectory }
@@ -76,6 +85,15 @@ module Program =
         { context with
             config.Output = outputsOption }
 
+    let stream (output: Outputs) (context: ExecContext) =
+        let outputsOption =
+            match output with
+            | File path -> path |> toOptionWithDefault output
+            | _ -> Some output
+
+        { context with
+            config.Stream = outputsOption }
+
     let workingDirectory (workingDirectory: string) (context: ExecContext) =
         { context with
             config.WorkingDirectory = Some workingDirectory }