1 files changed, 134 insertions, 0 deletions
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.m b/src/objective-c/GRPCClient/private/GRPCHost.m
new file mode 100644
index 0000000000..5d9c48a524
--- /dev/null
+++ b/src/objective-c/GRPCClient/private/GRPCHost.m
@@ -0,0 +1,134 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#import "GRPCHost.h"
+
+#include <grpc/grpc.h>
+
+#import "GRPCChannel.h"
+#import "GRPCCompletionQueue.h"
+#import "GRPCSecureChannel.h"
+#import "GRPCUnsecuredChannel.h"
+
+@interface GRPCHost ()
+// TODO(mlumish): Investigate whether caching channels with strong links is a good idea.
+@property(nonatomic, strong) GRPCChannel *channel;
+@end
+
+@implementation GRPCHost
+
++ (instancetype)hostWithAddress:(NSString *)address {
+  return [[self alloc] initWithAddress:address];
+}
+
+- (instancetype)init {
+  return [self initWithAddress:nil];
+}
+
+// Default initializer.
+- (instancetype)initWithAddress:(NSString *)address {
+
+  // Verify and normalize the address, and decide whether to use SSL.
+  if (![address rangeOfString:@"://"].length) {
+    // No scheme provided; assume https.
+    address = [@"https://" stringByAppendingString:address];
+  }
+  NSURL *hostURL = [NSURL URLWithString:address];
+  if (!hostURL) {
+    [NSException raise:NSInvalidArgumentException format:@"Invalid URL: %@", address];
+  }
+  NSString *scheme = hostURL.scheme;
+  if (![scheme isEqualToString:@"https"] && ![scheme isEqualToString:@"http"]) {
+    [NSException raise:NSInvalidArgumentException format:@"URL scheme %@ isn't supported.", scheme];
+  }
+  // If the user didn't specify a port (hostURL.port is nil), provide a default one.
+  NSNumber *port = hostURL.port ?: [scheme isEqualToString:@"https"] ? @443 : @80;
+  address = [@[hostURL.host, port] componentsJoinedByString:@":"];
+
+  // Look up the GRPCHost in the cache.
+  static NSMutableDictionary *hostCache;
+  static dispatch_once_t cacheInitialization;
+  dispatch_once(&cacheInitialization, ^{
+    hostCache = [NSMutableDictionary dictionary];
+  });
+  @synchronized(hostCache) {
+    GRPCHost *cachedHost = hostCache[address];
+    if (cachedHost) {
+      // We could verify here that the cached host uses the same protocol that we're expecting. But
+      // creating non-SSL channels by adding "http://" to the address is going away (to make the use
+      // of insecure channels less subtle), so it's not worth it now.
+      return cachedHost;
+    }
+
+    if ((self = [super init])) {
+      _address = address;
+      _secure = [scheme isEqualToString:@"https"];
+      hostCache[address] = self;
+    }
+    return self;
+  }
+}
+
+- (grpc_call *)unmanagedCallWithPath:(NSString *)path completionQueue:(GRPCCompletionQueue *)queue {
+  if (!queue || !path || !self.channel) {
+    return NULL;
+  }
+  return grpc_channel_create_call(self.channel.unmanagedChannel,
+                                  NULL, GRPC_PROPAGATE_DEFAULTS,
+                                  queue.unmanagedQueue,
+                                  path.UTF8String,
+                                  self.hostName.UTF8String,
+                                  gpr_inf_future(GPR_CLOCK_REALTIME));
+}
+
+- (GRPCChannel *)channel {
+  // Create it lazily, because we don't want to open a connection just because someone is
+  // configuring a host.
+  if (!_channel) {
+    if (_secure) {
+      _channel = [[GRPCSecureChannel alloc] initWithHost:_address
+                                      pathToCertificates:_pathToCertificates
+                                        hostNameOverride:_hostNameOverride];
+    } else {
+      _channel = [[GRPCUnsecuredChannel alloc] initWithHost:_address];
+    }
+  }
+  return _channel;
+}
+
+- (NSString *)hostName {
+  // TODO(jcanizales): Default to nil instead of _address when Issue #2635 is clarified.
+  return _hostNameOverride ?: _address;
+}
+
+@end