memcached

src/lib/functionlib.h

@@ -128,6 +128,23 @@ u64 int_val(string s, u32 base = 10)
 	return(strtoll(s.c_str(), 0, base));
 }
 
+string nibble(string& haystack, string delim)
+{
+	auto idx = haystack.find(delim);
+	if(idx == string::npos)
+	{
+		string result = haystack;
+		haystack = "";
+		return(result);
+	}
+	else
+	{
+		string result = haystack.substr(0, idx);
+		haystack = haystack.substr(idx+delim.length());
+		return(result);
+	}
+}
+
 string json_encode(DTree t)
 {
 	string result = "";

src/lib/sys.h

@@ -291,12 +291,34 @@ string socket_read(u64 sockfd, u32 max_length = 1024*128, u32 timeout = 1)
 	return("");
 }
 
+string memcache_escape_key(string key)
+{
+	string result;
+	for(auto c : key)
+	{
+		if(isspace(c))
+			c = '_';
+		result.append(1, c);
+	}
+	return(result);
+}
+
+StringList memcache_escape_keys(StringList keys)
+{
+	StringList result;
+	for(auto s : keys)
+	{
+		result.push_back(memcache_escape_key(s));
+	}
+	return(result);
+}
+
 u64 memcache_connect(string host = "127.0.0.1", short port = 11211)
 {
 	return(socket_connect(host, port));
 }
 
-string memcache_get_raw(u64 connection, string command)
+string memcache_command(u64 connection, string command)
 {
 	socket_write(connection, command+"\r\n");
 	return(socket_read(connection)); // FIXME: do multi-chunk until END line is received!
@@ -304,17 +326,52 @@ string memcache_get_raw(u64 connection, string command)
 
 bool memcache_set(u64 connection, string key, string value, u64 expires_in = 60*60)
 {
-	// to do: escape key string
 	socket_write(connection,
 		// set KEY META_DATA EXPIRY_TIME LENGTH_IN_BYTES
-		string("set ") + (key) + " 0 " + std::to_string(expires_in) + " " + std::to_string(value.length()) + "\r\n" +
+		string("set ") + memcache_escape_key(key) + " 0 " + std::to_string(expires_in) + " " + std::to_string(value.length()) + "\r\n" +
 		value + "\r\n");
 	return("STORED" == trim(socket_read(connection)));
 }
 
-string memcache_get(u64 connection, string key)
+bool memcache_delete(u64 connection, string key)
 {
-	// to do: escape key string
-	auto res = memcache_get_raw(connection, string("get ")+key);
-
+	socket_write(connection,
+		// set KEY META_DATA EXPIRY_TIME LENGTH_IN_BYTES
+		string("delete ") + memcache_escape_key(key) + "\r\n"
+		);
+	return("DELETED" == trim(socket_read(connection)));
+}
+
+string memcache_get(u64 connection, string key, string default_value = "")
+{
+	auto res = memcache_command(connection, string("get ")+memcache_escape_key(key));
+	string t = nibble(res, " ");
+	if(t == "VALUE")
+	{
+		string key = nibble(res, " ");
+		string meta = nibble(res, " ");
+		u32 length = stoi(nibble(res, "\r\n"));
+		return(res.substr(0, length));
+	}
+	return(default_value);
+}
+
+StringMap memcache_get_multiple(u64 connection, StringList keys)
+{
+	StringMap result;
+	// to do: escape key string
+	auto res = memcache_command(connection, string("get ")+join(memcache_escape_keys(keys), " "));
+	while(res.length() > 0)
+	{
+		string t = nibble(res, " ");
+		if(t == "VALUE")
+		{
+			string key = nibble(res, " ");
+			string meta = nibble(res, " ");
+			u32 length = stoi(nibble(res, "\r\n"));
+			result[key] = res.substr(0, length);
+			res = res.substr(length+2);
+		}
+	}
+	return(result);
 }

test/memcached.uce

@@ -17,7 +17,7 @@ RENDER()
 
 			auto sfd = memcache_connect();
 
-			echo(memcache_get_raw(sfd, "stats"));
+			echo(memcache_command(sfd, "stats"));
 
 		?></pre>
 
@@ -26,7 +26,10 @@ RENDER()
 		<pre><?
 
 			memcache_set(sfd, "test_key", "test_value");
-			echo(memcache_get_raw(sfd, "get test_key"));
+			memcache_set(sfd, "test_key2", "test_value2");
+			echo("raw:: "+memcache_command(sfd, "get test_key")+"\n");
+			echo("get:: "+memcache_get(sfd, "test_key")+"\n");
+			echo("multiple::\n"+var_dump(memcache_get_multiple(sfd, {"test_key", "test_key2"}))+"\n");
 
 		?></pre>
 

todo.txt

@@ -1,6 +1,5 @@
 Library
 =================================
-- memcached
 - mysql
 - sha1 / md5 / meow
 - cache