refactor: Refactor DescribeNetworkProfiles logging

test_runner/src/main/kotlin/ftl/api/NetworkProfile.kt

@@ -17,5 +17,9 @@ data class NetworkProfile(
         val burst: Float?
     )
 
+    data class ErrorMessage(
+        val message: String
+    )
+
     interface Fetch : () -> List<NetworkProfile>
 }

test_runner/src/main/kotlin/ftl/domain/DescribeNetworkProfiles.kt

@@ -1,14 +1,18 @@
 package ftl.domain
 
-import flank.common.logLn
+import ftl.api.NetworkProfile
 import ftl.environment.networkProfileDescription
+import ftl.presentation.Output
 import ftl.run.exception.FlankConfigurationError
 
-interface DescribeNetworkProfiles {
+interface DescribeNetworkProfiles : Output {
     val profileId: String
 }
 
 operator fun DescribeNetworkProfiles.invoke() {
     if (profileId.isBlank()) throw FlankConfigurationError("Argument PROFILE_ID must be specified.")
-    logLn(networkProfileDescription(profileId))
+    val description = networkProfileDescription(profileId)
+        ?: NetworkProfile.ErrorMessage("Unable to fetch profile [$profileId] description")
+
+    description.out()
 }

test_runner/src/main/kotlin/ftl/environment/NetworkProfileDescription.kt

@@ -3,49 +3,20 @@ package ftl.environment
 import ftl.api.NetworkProfile
 import ftl.api.fetchNetworkProfiles
 
-fun networkProfileDescription(profile: String) = fetchNetworkProfiles()
+fun networkProfileDescription(profile: String): NetworkProfile? = fetchNetworkProfiles()
     .find { it.id.equals(profile, ignoreCase = true) }
-    .toNullProof()
-    .prepareDescription()
-    ?: "Unable to fetch profile [$profile] description"
 
-private fun NetworkProfile?.toNullProof() = this?.run {
-    NetworkConfigurationWrapper(
-        downRule = wrappedOrEmpty(downRule),
-        upRule = wrappedOrEmpty(upRule),
-        id = id.toStringOrUnableToFetch()
-    )
-}
-
-private fun wrappedOrEmpty(rule: NetworkProfile.Rule?) = rule?.let {
-    Rule(
-        bandwidth = it.bandwidth.toStringOrUnableToFetch(),
-        delay = it.delay.toStringOrUnableToFetch(),
-        packetLossRatio = it.packetLossRatio.toStringOrUnableToFetch()
-    )
-} ?: emptyRule
-
-private const val UNABLE = "[Unable to fetch]"
-
-private fun Any?.toStringOrUnableToFetch() = this?.toString() ?: UNABLE
-
-private val emptyRule: Rule
-    get() = Rule(UNABLE, UNABLE, UNABLE)
-
-private fun NetworkConfigurationWrapper?.prepareDescription() = this?.run {
+fun NetworkProfile.prepareDescription(): String =
     """
 downRule:
-  bandwidth: ${downRule.bandwidth}
-  delay: ${downRule.delay}
-  packetLossRatio: ${downRule.packetLossRatio}
+  bandwidth: ${downRule.bandwidth ?: UNABLE_TO_FETCH}
+  delay: ${downRule.delay ?: UNABLE_TO_FETCH}
+  packetLossRatio: ${downRule.packetLossRatio ?: UNABLE_TO_FETCH}
 id: $id
 upRule:
-  bandwidth: ${upRule.bandwidth}
-  delay: ${upRule.delay}
-  packetLossRatio: ${upRule.packetLossRatio}
+  bandwidth: ${upRule.bandwidth ?: UNABLE_TO_FETCH}
+  delay: ${upRule.delay ?: UNABLE_TO_FETCH}
+  packetLossRatio: ${upRule.packetLossRatio ?: UNABLE_TO_FETCH}
     """.trimIndent()
-}
-
-private data class NetworkConfigurationWrapper(val downRule: Rule, val upRule: Rule, val id: String)
 
-private data class Rule(val bandwidth: String, val delay: String, val packetLossRatio: String)
+private const val UNABLE_TO_FETCH = "[Unable to fetch]"

test_runner/src/main/kotlin/ftl/presentation/Output.kt

@@ -0,0 +1,19 @@
+package ftl.presentation
+
+import flank.common.logLn
+
+/**
+ * The abstraction which allows passing output from the domain to presentation.
+ * Implement in domain top-level interfaces for getting access to outputting result structures.
+ * @property out The reference to outputting result function.
+ */
+interface Output {
+    val out: Any.() -> Unit
+}
+
+fun outputLogger(map: Any.() -> String): Any.() -> Unit = {
+    logLn(map())
+}
+
+fun Any.throwUnknownType(): Nothing =
+    throw IllegalArgumentException(javaClass.toGenericString())

test_runner/src/main/kotlin/ftl/presentation/cli/firebase/test/networkprofiles/NetworkProfilesDescribeCommand.kt

@@ -1,7 +1,11 @@
 package ftl.presentation.cli.firebase.test.networkprofiles
 
+import ftl.api.NetworkProfile
 import ftl.domain.DescribeNetworkProfiles
 import ftl.domain.invoke
+import ftl.environment.prepareDescription
+import ftl.presentation.outputLogger
+import ftl.presentation.throwUnknownType
 import picocli.CommandLine
 
 @CommandLine.Command(
@@ -32,4 +36,12 @@ class NetworkProfilesDescribeCommand :
     override var profileId: String = ""
 
     override fun run() = invoke()
+
+    override val out = outputLogger {
+        when (this) {
+            is NetworkProfile -> prepareDescription()
+            is NetworkProfile.ErrorMessage -> message
+            else -> throwUnknownType()
+        }
+    }
 }