Fix #258 - Queued fs calls hang when fs goes into error state due to provider.open error

src/filesystem/interface.js

@@ -223,8 +223,8 @@ function FileSystem(options, callback) {
         fs.readyState = FS_ERROR;
       } else {
         fs.readyState = FS_READY;
-        runQueued();
       }
+      runQueued();
       callback(error, fs);
     }
 
@@ -301,6 +301,13 @@ FileSystem.providers = providers;
     var error = fs.queueOrRun(function() {
       var context = fs.provider.openReadWriteContext();
 
+      // Fail early if the filesystem is in an error state (e.g.,
+      // provider failed to open.
+      if(FS_ERROR === fs.readyState) {
+        var err = new Errors.EFILESYSTEMERROR('filesystem unavailable, operation canceled');
+        return callback.call(fs, err);
+      }
+
       // Wrap the callback so we can explicitly close the context
       function complete() {
         context.close();

tests/bugs/issue258.js

@@ -0,0 +1,89 @@
+var Filer = require('../..');
+var util = require('../lib/test-utils.js');
+var expect = require('chai').expect;
+var setImmediate = require('../../lib/async.js').setImmediate;
+
+describe('Queued operations should error when fs is in error state, issue 258', function() {
+  var provider;
+
+  // Provider that does nothing but fail on open.
+  function FailingProviderContext(){}
+  FailingProviderContext.prototype.clear = function(callback) {
+    this.failCallback(callback);
+  };
+  FailingProviderContext.prototype.getObject =
+  FailingProviderContext.prototype.getBuffer = function(key, callback) {
+    this.failCallback(callback);
+  };
+  FailingProviderContext.prototype.putObject =
+  FailingProviderContext.prototype.putBuffer = function(key, value, callback) {
+    this.failCallback(callback);
+  };
+  FailingProviderContext.prototype.delete = function(key, callback) {
+    this.failCallback(callback);
+  };
+
+  function FailingProvider() {
+    var self = this;
+    self.name = 'failure';
+    self.open = function(callback) {
+      // Wait until caller tells us to fail
+      self.failNow = function() {
+        self.failCallback(callback);
+      };
+    };
+    self.failCallback = function(callback) {
+      setImmediate(function() {
+        callback(new Error);
+      });
+    };
+  }
+  FailingProvider.prototype.getReadWriteContext =
+  FailingProvider.prototype.getReadWriteContext = function() {
+    return new FailingProviderContext();
+  };
+
+  beforeEach(function() {
+    provider = new FailingProvider();
+  });
+
+  afterEach(function() {
+    provider = null;
+  });
+
+  it('should get EFILESYSTEMERROR errors on callbacks to queued operations on provider error', function(done) {
+    var errCount = 0;
+    var fs = new Filer.FileSystem({provider: provider});
+
+    function maybeDone(err) {
+      expect(err).to.exist;
+      expect(err.code).to.equal('EFILESYSTEMERROR');
+      errCount++;
+
+      if(errCount === 2) {
+        done();
+      }
+    }
+
+    // Queue some fs operations, and expect them to fail
+    fs.mkdir('/tmp', maybeDone);
+    fs.writeFile('/file', 'data', maybeDone);
+
+    // Operations are queued, tell the provider to fail now.
+    provider.failNow();
+  });
+
+  it('should get EFILESYSTEMERROR errors on callbacks to queued operations after ready callback', function(done) {
+    var fs = new Filer.FileSystem({provider: provider}, function(err) {
+      expect(err).to.exist;
+
+      // Queue is drained, but new operations should also fail
+      fs.mkdir('/tmp', function(err) {
+        expect(err).to.exist;
+        expect(err.code).to.equal('EFILESYSTEMERROR');
+        done();
+      });
+    });
+    provider.failNow();
+  });
+});

tests/index.js

@@ -72,4 +72,4 @@ require("./bugs/issue249");
 require("./bugs/ls-depth-bug");
 require("./bugs/issue247.js");
 require("./bugs/issue254.js");
-
+require("./bugs/issue258.js");