[SOLVED] Kotlin ProcessBuilder Incorrectly Splitting Command, Leading to Multiple Arguments

Issue

I'm encountering an issue executing a command using Kotlin's ProcessBuilder. The command is being split into multiple arguments, resulting in an error: at most 1 query string can be specified as an argument, got 10.

Relevant Code:

override fun fetchRecords(startTime: String, stopTime: String, bucket: String): List<String> {
val result = runCommand(
    "influx query 'from(bucket: \"$bucket\") |> range(start: $startTime) |> pivot(rowKey: [\"_time\"], columnKey:[\"_field\"], valueColumn:\"_value\")'"
)
// ...
}

private fun runCommand(command: String, workingDir: File = File(".")): String {
    val parts = command.split("\\s".toRegex())
    val proc = ProcessBuilder(*parts.toTypedArray())
       // ...
}

Error Message:

Command error: Error: at most 1 query string can be specified as an argument, got 10

Attempted Fixes:

• I've tried using a multi-line string literal without explicit newline characters, but the error persists.

Questions:

• What's causing the incorrect argument splitting?
• How can I ensure the command is passed as a single argument? -Are there alternative approaches to executing commands in Kotlin that might avoid this issue?
• Should I consider using a different library for command execution?

Additional Context:

• I'm using Kotlin version 1.9.20
• The command being executed is influx query 'from(bucket: "1CATUSDTTimeSeries1Hour") |> range(start: 0) |> pivot(rowKey: ["_time"], columnKey:["_field"], valueColumn:"_value")' which works fine with terminal.

Any guidance would be greatly appreciated!

Solution

Instead of parsing the command line arguments yourself (which is not trivial), take an Array<String> instead, and let the caller split the arguments.

private fun runCommand(command: Array<String>, workingDir: File = File(".")): String {
    val proc = ProcessBuilder(*command)
    ...
}

val result = runCommand(
    arrayOf("influx", "query", 
    "from(bucket: \"$bucket\") |> range(start: $startTime) |> pivot(rowKey: [\"_time\"], columnKey:[\"_field\"], valueColumn:\"_value\")"
    )
)

Alternatively, send the whole command to sh (or whatever shell is on the system), and let it parse the arguments. This of course, is platform dependent.

private fun runCommand(command: String, workingDir: File = File(".")): String {
    val proc = ProcessBuilder(arrayOf("sh", "-c", command))
    ...
}

Answered By - Sweeper

Answer Checked By - Clifford M. (WPSolving Volunteer)