Fixed issue where an unknown exchange type would cause an exception.

README.md

@@ -14,10 +14,10 @@ $ npm install --save rabbit-mermaid
 ## Usage
 
 ```js
-const rabbitmermaid = require("rabbit-mermaid");
+const { MermaidGenerator } = require("rabbit-mermaid");
 const topology = require("./topology.json");
-
-rabbitmermaid(topology);
+const mermaidGenerator = new MermaidGenerator(topology);
+mermaidGenerator.generate();
 ```
 
 ## License

lib/__tests__/mermaid-generator.test.js

@@ -5,6 +5,7 @@ const fanout = require("./fanout.json");
 const topic = require("./topic.json");
 const multiple = require("./multiple.json");
 const exchangeToExhange = require("./exchangeToExchange.json");
+const unknownExchange = require("./unknownExchange.json");
 
 describe("MermaidGenerator", () => {
   it("generates a string", () => {
@@ -26,6 +27,20 @@ end`;
     assert.deepEqual(mermaidGenerator.generate(), expectedString);
   });
 
+  it("ignores exchange types it does not recognize", () => {
+    const mermaidGenerator = new MermaidGenerator(unknownExchange, {});
+    const expectedString = `graph LR
+subgraph Images
+Images(("Images<br/>(direct)"))
+Images --routing_key=images.archive--> archiver1("archiver1")
+Images --routing_key=images.archive--> archiver2("archiver2")
+Images --routing_key=images.crop--> cropper("cropper")
+Images --routing_key=images.resize--> resizer("resizer")
+end`;
+
+    assert.deepEqual(mermaidGenerator.generate(), expectedString);
+  });
+
   it("generates a fanout exchange block with queue bindings", () => {
     const mermaidGenerator = new MermaidGenerator(fanout, {});
     const expectedString = `graph LR

lib/__tests__/unknownExchange.json

@@ -0,0 +1,94 @@
+{
+  "exchanges": [
+    {
+      "name": "images",
+      "vhost": "/",
+      "type": "direct",
+      "durable": true,
+      "auto_delete": false,
+      "internal": false,
+      "arguments": {}
+    },
+    {
+      "name": "breaker",
+      "vhost": "/",
+      "type": "header",
+      "durable": true,
+      "auto_delete": false,
+      "internal": false,
+      "arguments": {}
+    }
+  ],
+  "queues": [
+    {
+      "name": "archiver1",
+      "vhost": "/",
+      "durable": true,
+      "auto_delete": false,
+      "arguments": {}
+    },
+    {
+      "name": "archiver2",
+      "vhost": "/",
+      "durable": true,
+      "auto_delete": false,
+      "arguments": {}
+    },
+    {
+      "name": "cropper",
+      "vhost": "/",
+      "durable": true,
+      "auto_delete": false,
+      "arguments": {}
+    },
+    {
+      "name": "resizer",
+      "vhost": "/",
+      "durable": true,
+      "auto_delete": false,
+      "arguments": {}
+    }
+  ],
+  "bindings": [
+    {
+      "source": "images",
+      "vhost": "/",
+      "destination": "archiver1",
+      "destination_type": "queue",
+      "routing_key": "images.archive",
+      "arguments": {}
+    },
+    {
+      "source": "breaker",
+      "vhost": "/",
+      "destination": "archiver1",
+      "destination_type": "queue",
+      "routing_key": "images.archive",
+      "arguments": {}
+    },
+    {
+      "source": "images",
+      "vhost": "/",
+      "destination": "archiver2",
+      "destination_type": "queue",
+      "routing_key": "images.archive",
+      "arguments": {}
+    },
+    {
+      "source": "images",
+      "vhost": "/",
+      "destination": "cropper",
+      "destination_type": "queue",
+      "routing_key": "images.crop",
+      "arguments": {}
+    },
+    {
+      "source": "images",
+      "vhost": "/",
+      "destination": "resizer",
+      "destination_type": "queue",
+      "routing_key": "images.resize",
+      "arguments": {}
+    }
+  ]
+}

lib/mermaid-generator.js

@@ -15,10 +15,17 @@ class MermaidGenerator {
     return format;
   }
 
+  isSupportedExchange(ex) {
+    return ex.type === "direct" || ex.type === "fanout" || ex.type === "topic";
+  }
+
   processExchangeBlocks(json) {
     const exchanges = json.exchanges;
     const exBuffer = [];
-    exchanges.forEach(ex => {
+    const supportedExchanges = exchanges.filter(ex =>
+      this.isSupportedExchange(ex)
+    );
+    supportedExchanges.forEach(ex => {
       exBuffer.push(this.genExchangeBlock(ex));
     });