Implement messages.error

README.md

@@ -36,13 +36,13 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
   - [x] message encodings
   - [x] service features
   - [x] pubkey features
-- [ ] Message types
+- [x] Message types
   - [x] version
   - [x] verack
   - [x] addr
   - [x] inv
   - [x] getdata
-  - [ ] error
+  - [x] error
   - [x] object
 - [ ] Object types
   - [ ] getpubkey
@@ -58,9 +58,6 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
     - [x] getRipe
     - [x] fromRandom
     - [ ] fromPassphrase
-  - [ ] Message
-    - [ ] encrypt
-    - [ ] decrypt
   - [x] UserAgent
 - [ ] Parse PyBitmessage configs
   - [ ] keys.dat

lib/messages.js

@@ -1,6 +1,8 @@
 /**
  * Working with messages.
  * @see {@link https://bitmessage.org/wiki/Protocol_specification#Message_types}
+ * @see {@link https://bitmessage.org/wiki/Protocol_specification_v3#Message_types}
+ * @see {@link https://bitmessage.org/Bitmessage%20Technical%20Paper.pdf}
  * @module bitmessage/messages
  */
 
@@ -23,8 +25,7 @@ exports.version = {
   /**
    * Decode `version` payload.
    * NOTE: `nonce` is copied.
-   * @param {Buffer} buf - Buffer that starts with encoded `version`
+   * @param {Buffer} buf - `version` payload
-   * payload
    * @return {Object} Decoded `version` structure.
    */
   decode: function(buf) {
@@ -107,7 +108,7 @@ exports.version = {
 exports.addr = {
   /**
    * Decode `addr` payload.
-   * @param {Buffer} buf - Buffer that starts with encoded `addr` payload
+   * @param {Buffer} buf - `addr` payload
    * @return {Object} Decoded `addr` structure.
    */
   decode: function(buf) {
@@ -150,7 +151,7 @@ exports.addr = {
 var inv = exports.inv = {
   /**
    * Decode `inv` payload.
-   * @param {Buffer} buf - Buffer that starts with encoded `inv` payload
+   * @param {Buffer} buf - `inv` payload
    * @return {Object} Decoded `inv` structure.
    */
   decode: function(buf) {
@@ -173,7 +174,7 @@ var inv = exports.inv = {
 
   /**
    * Encode `inv` payload.
-   * @param {Buffer[]} inventory - Inventory vectors (encoded)
+   * @param {Buffer[]} inventory - Inventory vector list (encoded)
    * @return {Buffer} Encoded `inv` payload.
    */
   encode: function(inventory) {
@@ -192,6 +193,74 @@ var inv = exports.inv = {
  */
 exports.getdata = inv;
 
+/**
+ * `error` message.
+ * @see {@link https://bitmessage.org/wiki/Protocol_specification_v3#error}
+ * @namespace
+ */
+var error = exports.error = {
+  /**
+   * Just a warning.
+   */
+  WARNING: 0,
+
+  /**
+   * It's an error, something was going wrong (e.g. an object got lost).
+   */
+  ERROR: 1,
+
+  /**
+   * It's a fatal error. The node will drop the line for that error and
+   * maybe ban you for some time.
+   */
+  FATAL: 2,
+
+  /**
+   * Decode `error` payload.
+   * @param {Buffer} buf - `error` payload
+   * @return {Object} Decoded `error` structure.
+   */
+  decode: function(buf) {
+    assert(buf.length >= 4, "Buffer is too small");
+    var decodedFatal = structs.var_int.decode(buf);
+    var decodedBanTime = structs.var_int.decode(decodedFatal.rest);
+    var decodedVector = structs.var_str.decode(decodedBanTime.rest);
+    var decodedErrorText = structs.var_str.decode(decodedVector.rest);
+    var length = (
+      decodedFatal.length +
+      decodedBanTime.length +
+      decodedVector.length +
+      decodedErrorText.length
+    );
+    return {
+      fatal: decodedFatal.value,
+      banTime: decodedBanTime.value,
+      vector: decodedVector.str,
+      errorText: decodedErrorText.str,
+      // Real data length.
+      length: length,
+    };
+  },
+
+  /**
+   * Encode `error` payload.
+   * @param {Object} opts - Error options
+   * @return {Buffer} Encoded `error` payload.
+   */
+  encode: function(opts) {
+    var fatal = opts.fatal || error.WARNING;
+    var banTime = opts.banTime || 0;
+    var vector = opts.vector || "";
+    var errorText = opts.errorText || "";
+    return Buffer.concat([
+      structs.var_int.encode(fatal),
+      structs.var_int.encode(banTime),
+      structs.var_str.encode(vector),
+      structs.var_str.encode(errorText),
+    ]);
+  },
+};
+
 /**
  * `object` message. An `object` is a message which is shared throughout
  * a stream. It is the only message which propagates; all others are
@@ -203,8 +272,7 @@ exports.object = {
   /**
    * Decode `object` payload.
    * NOTE: `nonce` and `payload` are copied.
-   * @param {Buffer} buf - Buffer that starts with encoded `object`
+   * @param {Buffer} buf - `object` payload
-   * payload
    * @return {Object} Decoded `object` structure.
    */
   decode: function(buf) {

test.js

@@ -21,6 +21,7 @@ var messages = bitmessage.messages;
 var version = messages.version;
 var addr = messages.addr;
 var inv = messages.inv;
+var error = messages.error;
 var object = messages.object;
 var WIF = bitmessage.WIF;
 var POW = bitmessage.POW;
@@ -354,6 +355,29 @@ describe("Message types", function() {
     });
   });
 
+  describe("error", function() {
+    it("should encode and decode", function() {
+      var res = error.decode(error.encode({errorText: "test"}));
+      expect(res.fatal).to.equal(0);
+      expect(res.banTime).to.equal(0);
+      expect(res.vector).to.equal("");
+      expect(res.errorText).to.equal("test");
+      expect(res.length).to.equal(8);
+
+      var res = error.decode(error.encode({
+        fatal: error.FATAL,
+        banTime: 120,
+        vector: "123",
+        errorText: "fatal error",
+      }));
+      expect(res.fatal).to.equal(2);
+      expect(res.banTime).to.equal(120);
+      expect(res.vector).to.equal("123");
+      expect(res.errorText).to.equal("fatal error");
+      expect(res.length).to.equal(18);
+    });
+  });
+
   describe("object", function() {
     it("should encode and decode", function() {
       var nonce = Buffer(8);