Expose styx origins config file in Admin interface (Issue #496)

components/proxy/src/main/java/com/hotels/styx/admin/handlers/TextHttpHandler.java

@@ -0,0 +1,57 @@
+/*
+  Copyright (C) 2013-2019 Expedia Inc.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+ */
+package com.hotels.styx.admin.handlers;
+
+import com.hotels.styx.api.ByteStream;
+import com.hotels.styx.api.Eventual;
+import com.hotels.styx.api.HttpHandler;
+import com.hotels.styx.api.HttpInterceptor;
+import com.hotels.styx.api.LiveHttpRequest;
+import com.hotels.styx.api.LiveHttpResponse;
+
+import java.util.function.Supplier;
+
+import static com.google.common.net.MediaType.PLAIN_TEXT_UTF_8;
+import static com.hotels.styx.api.HttpHeaderNames.CONTENT_TYPE;
+import static com.hotels.styx.api.HttpResponseStatus.OK;
+import static com.hotels.styx.api.LiveHttpResponse.response;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.util.Objects.requireNonNull;
+
+/**
+ * Responds with UTF8 text stream.
+ */
+public class TextHttpHandler implements HttpHandler {
+
+    private final Supplier<String> text;
+
+    public TextHttpHandler(Supplier<String> text) {
+        this.text = requireNonNull(text, "text supplier cannot be null");
+    }
+
+    @Override
+    public Eventual<LiveHttpResponse> handle(LiveHttpRequest request, HttpInterceptor.Context context) {
+        return Eventual.of(createResponse());
+    }
+
+    protected LiveHttpResponse createResponse() {
+        return response(OK)
+                .disableCaching()
+                .addHeader(CONTENT_TYPE, PLAIN_TEXT_UTF_8)
+                .body(ByteStream.from(text.get(), UTF_8))
+                .build();
+    }
+}

components/proxy/src/main/kotlin/com/hotels/styx/services/YamlFileConfigurationService.kt

@@ -16,6 +16,7 @@
 package com.hotels.styx.services
 
 import com.fasterxml.jackson.databind.JsonNode
+import com.hotels.styx.admin.handlers.TextHttpHandler
 import com.hotels.styx.api.extension.service.spi.StyxService
 import com.hotels.styx.config.schema.SchemaDsl
 import com.hotels.styx.config.schema.SchemaDsl.bool
@@ -56,6 +57,9 @@ internal class YamlFileConfigurationService(
 
     private val healthMonitors = AtomicReference<List<Pair<String, ProviderObjectRecord>>>(listOf())
 
+    @Volatile
+    private var originsConfig = ""
+
     companion object {
         @JvmField
         val SCHEMA = SchemaDsl.`object`(
@@ -78,6 +82,10 @@ internal class YamlFileConfigurationService(
                 LOGGER.info("service stopped")
             }
 
+    override fun adminInterfaceHandlers() =
+        mapOf("origins" to TextHttpHandler { originsConfig })
+
+
     fun reloadAction(content: String): Unit {
         LOGGER.info("New origins configuration: \n$content")
 
@@ -91,6 +99,8 @@ internal class YamlFileConfigurationService(
         }.mapCatching { (healthMonitors, routingObjectDefs) ->
             updateRoutingObjects(routingObjectDefs)
             updateHealthCheckServices(serviceDb, healthMonitors)
+        }.onSuccess {
+            originsConfig = content
             initialised.countDown()
         }.onFailure {
             LOGGER.error("Failed to reload new configuration. cause='{}'", it.message, it)

system-tests/ft-suite/src/test/kotlin/com/hotels/styx/admin/OriginsFileCompatibilitySpec.kt

@@ -82,12 +82,13 @@ class OriginsFileCompatibilitySpec : FunSpec() {
 
     init {
         context("Styx server starts") {
-            writeOrigins("""
+            val originsFile = """
                 - id: appA
                   path: "/"
                   origins:
                   - { id: "appA-01", host: "localhost:${mockServerA01.port()}" } 
-            """.trimIndent())
+            """.trimIndent()
+            writeOrigins(originsFile)
             styxServer.restart()
 
             test("It populates forwarding path from the origins yaml file") {
@@ -102,6 +103,17 @@ class OriginsFileCompatibilitySpec : FunSpec() {
                             }
                 }
             }
+
+            test("The origins config file is returned from the admin service") {
+                client.send(get("/admin/providers/originsFileLoader/origins")
+                        .header(HOST, styxServer().adminHostHeader())
+                        .build())
+                        .wait()!!
+                        .let {
+                            it.status() shouldBe OK
+                            it.bodyAs(UTF_8) shouldBe originsFile
+                        }
+            }
         }
 
         context("Origins configuration changes") {
@@ -419,6 +431,14 @@ class OriginsFileCompatibilitySpec : FunSpec() {
         }
 
         context("Admin interface") {
+
+            val validOriginsFile = """
+                - id: appA
+                  path: "/"
+                  origins:
+                  - { id: "appA-01", host: "localhost:${mockServerA01.port()}" } 
+            """.trimIndent()
+
             test("Styx dashboard is disabled") {
                 client.send(get("/")
                         .header(HOST, styxServer().adminHostHeader())
@@ -447,6 +467,42 @@ class OriginsFileCompatibilitySpec : FunSpec() {
                             it.bodyAs(UTF_8) shouldContain """<li><a href='/admin/configuration?pretty'>Configuration</a></li>"""
                         }
             }
+
+            test("Modified origins config is returned after update") {
+
+                writeOrigins(validOriginsFile)
+
+                eventually(2.seconds, AssertionError::class.java) {
+                    client.send(get("/admin/providers/originsFileLoader/origins")
+                            .header(HOST, styxServer().adminHostHeader())
+                            .build())
+                            .wait()!!
+                            .let {
+                                it.status() shouldBe OK
+                                it.bodyAs(UTF_8) shouldBe validOriginsFile
+                            }
+                }
+            }
+
+            test("Original origins config is returned after invalid update") {
+
+                writeOrigins("""
+                    - id: appA
+                    - this file has somehow corrupted
+                      .. bl;ah blah" 
+                    """.trimIndent())
+
+                eventually(2.seconds, AssertionError::class.java) {
+                    client.send(get("/admin/providers/originsFileLoader/origins")
+                            .header(HOST, styxServer().adminHostHeader())
+                            .build())
+                            .wait()!!
+                            .let {
+                                it.status() shouldBe OK
+                                it.bodyAs(UTF_8) shouldBe validOriginsFile
+                            }
+                }
+            }
         }
 
         context("Creates a health checking service") {
@@ -592,12 +648,13 @@ class OriginsFileCompatibilitySpec : FunSpec() {
 
 
         context("Error scenarios") {
-            writeOrigins("""
+            val originsFile = """
                 - id: appA
                   path: "/"
                   origins:
                   - { id: "appA-01", host: "localhost:${mockServerA01.port()}" } 
-                """.trimIndent())
+                """.trimIndent()
+            writeOrigins(originsFile)
             styxServer.restart()
 
             test("Keeps the original configuration when a one has problems") {
@@ -628,12 +685,13 @@ class OriginsFileCompatibilitySpec : FunSpec() {
             }
 
             test("Reloads a new configuration after error") {
-                writeOrigins("""
+                val newOriginsFile = """
                 - id: appA
                   path: "/"
                   origins:
                   - { id: "appA-02", host: "localhost:${mockServerA02.port()}" } 
-                """.trimIndent())
+                """.trimIndent()
+                writeOrigins(newOriginsFile)
 
                 eventually(2.seconds, AssertionError::class.java) {
                     client.send(get("/20")