Refactor instance communication

Change Instance class to be a subclass of Link and refactor the
communication to and establisment of instances to use a virtual
connection between the slave and the instance.  This is simplifies the
implementation of plugin communication for instances.

Replace InstanceRequest with a forwardTo option to Request which does
the task of forwarding in a much cleaner way.

test/client.js

@@ -2,11 +2,12 @@ const assert = require('assert').strict;
 const path = require('path');
 const fs = require('fs-extra');
 
+const link = require("lib/link");
 const client = require("../client");
 
 describe("Client testing", function() {
 	describe("class Instance", function() {
-		let instance = new client._Instance("dir", "factorioDir", { name:"foo" })
+		let instance = new client._Instance(new link.VirtualConnector(), "dir", "factorioDir", { name:"foo" });
 		it("should give the name on .name", function() {
 			assert.equal(instance.name, "foo");
 		})
@@ -81,7 +82,9 @@ describe("Client testing", function() {
 		fs.outputFileSync(path.join(testDir, "shared", "mod_a.zip"), "a");
 		fs.outputFileSync(path.join(testDir, "shared", "mod_b.zip"), "b");
 		fs.outputFileSync(path.join(testDir, "shared", "mod.dat"), "c");
-		let instance = new client._Instance(path.join(testDir, "instance"), "factorioDir", { name: "test" });
+		let instance = new client._Instance(
+			new link.VirtualConnector(), path.join(testDir, "instance"), "factorioDir", { name: "test" }
+		);
 		fs.outputFileSync(instance.path("mods", "mod_i.zip"), "i");
 
 		let discardingLogger = {
@@ -127,4 +130,24 @@ describe("Client testing", function() {
 			assert.equal(await fs.readFile(instance.path("mods", "mod_i.zip"), "utf-8"), "i");
 		});
 	});
+
+	describe("discoverInstances()", function() {
+		it("should discover test instance", async function() {
+			let logger = { log: () => {}, error: () => {} };
+			let instancePath = path.join("test", "file", "instances");
+			let instanceInfos = await client._discoverInstances(instancePath, logger);
+			assert.deepEqual(instanceInfos, new Map([
+				[1, {
+					config: {
+						id: 1,
+						name: "test",
+						factorioPort: null,
+						clientPort: null,
+						clientPassword: null
+					},
+					path: path.join(instancePath, "test"),
+				}],
+			]));
+		});
+	});
 });

test/file/instances/test/config.json

@@ -0,0 +1,7 @@
+{
+    "id": 1,
+    "name": "test",
+    "factorioPort": null,
+    "clientPort": null,
+    "clientPassword": null
+}

test/integration/clusterio.js

@@ -63,7 +63,6 @@ describe("Integration of Clusterio", function() {
 			masterAuthToken: "invalid",
 			publicIP: "invalid",
 		});
-		testSlave.instances = await testSlave.findInstances();
 		testSlaveConnection = new master._SlaveConnection({ agent: "test", version, name: "slave", id: 4}, slaveServer);
 		master._slaveConnections.set(4, testSlaveConnection);
 	});

test/lib/link/messages.js

@@ -18,6 +18,15 @@ describe("lib/link/messages", function() {
 			links: ['source-target'],
 		});
 
+		describe("constructor", function() {
+			it("should throw on invalid forwardTo", function() {
+				assert.throws(
+					() => new link.Request({ forwardTo: 'invalid'}),
+					new Error("Invalid forwardTo value invalid")
+				);
+			});
+		});
+
 		describe(".attach()", function() {
 			it("should attach validator to a source link", function() {
 				testRequest.attach(testSourceLink);
@@ -35,20 +44,6 @@ describe("lib/link/messages", function() {
 				testRequest.attach(testTargetLink, async (message) => handlerResult );
 				assert(testTargetLink._handlers.has('test_request'), "Handler was not set");
 			});
-			it("should throw on handler returning object with seq", async function() {
-				handlerResult = { seq: 3 };
-				testTargetLink._handlers.get('test_request')({ seq: 2 });
-				let result = await new Promise(resolve => {
-					testTargetLink.connector.send = (type, data) => resolve({ type, data });
-				});
-				assert.deepEqual(result, {
-					type: 'test_response',
-					data: {
-						error: "response contains reserved property 'seq'",
-						seq: 2,
-					},
-				});
-			});
 			it("should send result of calling the handler", async function() {
 				handlerResult = { test: "handler" };
 				testTargetLink._handlers.get('test_request')({ seq: 2 });
@@ -107,15 +102,21 @@ describe("lib/link/messages", function() {
 		});
 	});
 
-	describe("class InstanceRequest", function() {
-	});
-
 	describe("class Event", function() {
 		let testEvent = new link.Event({
 			type: 'test',
 			links: ['source-target'],
 		});
 
+		describe("constructor", function() {
+			it("should throw on invalid forwardTo", function() {
+				assert.throws(
+					() => new link.Event({ forwardTo: 'invalid'}),
+					new Error("Invalid forwardTo value invalid")
+				);
+			});
+		});
+
 		describe(".attach()", function() {
 			it("should throw if missing handler on target link", function() {
 				assert.throws(