Add a README.

README.md

@@ -0,0 +1,67 @@
+# CXML-RPC: An xml-rpc library for Common Lisp
+
+This library implements xml-rpc client and server functionality using [Drakma](http://weitz.de/drakma), [CXML](http://common-lisp.net/project/cxml/) and [Hunchentoot](http://weitz.de/hunchentoot). 
+
+## Installation
+
+
+Get it via git:
+
+	git clone http://github.com/antifuchs/cxml-rpc
+
+Then adjust your ASDF to find cxml-rpc.asd. After that, 
+
+	(asdf:oos 'asdf:load-op :cxml-rpc)
+
+## Usage
+
+
+### An XML-RPC Client
+
+Acting as an XML-RPC client is pretty easy: Just call the functions on the endpoints you need. The function's first return value is the value returned by the server, and the second return value is its type.
+
+	* (xrpc:call "http://betty.userland.com/RPC2" "examples.getStateName" '(:integer 41))
+	"South Dakota"
+	:STRING
+
+##### Argument passing
+
+Since the mapping of CL types to XML-RPC types is not easily DWIM-able, you need to pass args with explicit type hints. CXML-RPC maps these types (as keywords):
+
+* `:boolean` - generalized boolean
+* `:integer` - 4-octet integers
+* `:double` - floating-point doubles
+* `:string` - strings
+* `:time` - universal times as CL integers
+* `:base64` - strings, file streams or vectors containing (unsigned-byte 8) elements.
+* `:struct` - alists
+* `:array` - sequences
+
+### An XML-RPC Server
+
+You can run multiple XML RPC handlers in your hunchentoot instance: These are identified by a handler tag that you can choose. This tag is not exposed to the outside world, so you can run multiple sites (or endpoints) with a different set of xml-rpc methods in the same lisp image.
+
+#### Step one: Teach hunchentoot about your handler.
+
+	(push 
+         (hunchentoot:create-prefix-dispatcher "/RPC2" 
+	                                       (cxml:cxml-rpc-method-handler 'some-tag))
+	 hunchentoot:*dispatch-table*)
+
+This tells hunchentoot to dispatch xml-rpc calls on /RPC2 to dispatch xml-rpc methods. This handler will serve only methods that are defined with the group tag some-tag.
+
+#### Step two: Define methods.
+
+Define-xrpc-method is what you use to create a function that can be called from xml-rpc. Its arguments are:
+
+1. The function name and handler group (following the example above, that should be some-tag),
+2. a list of argument variables,
+3. a type signature: First the return type, then the parameter types,
+4. an optional docstring.
+
+CXML-RPC allows introspection via the system.getCapabilities, system.listMethods, system.methodHelp, and system.methodSignature.
+
+	(define-xrpc-method (add some-tag) (a b) (:integer :integer :integer)
+	  "Add two numbers"
+	  (+ a b))
+