# openrpc
**Repository Path**: macro/openrpc
## Basic Information
- **Project Name**: openrpc
- **Description**: No description available
- **Primary Language**: Common Lisp
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No
## Statistics
- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-07-28
- **Last Updated**: 2025-07-28
## Categories & Tags
**Categories**: Uncategorized
**Tags**: None
## README
# OpenRPC for Common Lisp
[][4bbd]
This framework is built on top of [JSON-RPC][c597] and [`Clack`][75f7]. Comparing to `JSON-RPC` library,
it provides these key features:
* Automatic [OpenRPC spec][3160] generation.
* Automatic `JSON-RPC` client building by Open`RPC` spec. This includes creation of Common Lisp classes and methods
for making `RPC` requests and returning native `CL` objects.
* On both server and client sides your code looks very lispy, all `JSON` marshalling is done under the hood.
## Server
### OPENRPC-SERVER ASDF System Details
* Description: Open`RPC` server implementation for Common Lisp.
* Licence: `BSD`
* Author: Alexander Artemenko
* Homepage: [https://40ants.com/openrpc/][348e]
* Source control: [GIT][76b5]
* Depends on: [alexandria][8236], [clack-cors][087e], [clack-prometheus][babd], [closer-mop][61a4], [jsonrpc][a9bd], [lack-request][6a02], [lambda-fiddle][3ad9], [local-time][46a1], [log4cl][7f8b], [log4cl-extras][691c], [serapeum][c41d], [str][ef7f], [websocket-driver][4f50], [yason][aba2]
### Defining Methods
Here is an example of openrpc-server `ASDF` system allows to define
`JSON-RPC` methods and data-structures they return.
Let's see how we can define an [`api`][5d14] for usual PetShop example.
#### Simple Example
First, we will operate on usual Common Lisp class:
```
(defclass pet ()
((id :initarg :id
:type integer
:reader pet-id)
(name :initarg :name
:type string
:reader pet-name)
(tag :initarg :tag
:type string
:reader pet-tag)))
```
Now we can define an `RPC` method to create a new pet:
```
(openrpc-server:define-rpc-method create-pet (name tag)
(:summary "Short method docstring.")
(:description "Lengthy description of the method.")
(:param name string "Pet's name"
:description "This is a long description of the parameter.")
(:param tag string "Old param, don't use it anymore." :deprecated t)
(:result pet)
(let* ((new-id (get-new-id))
(pet (make-instance 'pet
:id new-id
:name name
:tag tag)))
(setf (gethash new-id *pets*)
pet)
pet))
```
Here we should explicitly specify type for each parameter and result's type.
Pay attention, the result type is `PET`. [`openrpc-server`][24be] system takes care on serializing
objects and you can retrieve an Open`RPC` spec for any type, using [`type-to-schema`][4de0] generic-function:
```
CL-USER> (serapeum:toggle-pretty-print-hash-table)
T
CL-USER> (openrpc-server:type-to-schema 'pet)
(SERAPEUM:DICT
"type" "object"
"properties" (SERAPEUM:DICT
"id" (SERAPEUM:DICT
"type" "integer"
)
"name" (SERAPEUM:DICT
"type" "string"
)
"tag" (SERAPEUM:DICT
"type" "string"
)
)
"required" '("tag" "name" "id")
"x-cl-class" "PET"
"x-cl-package" "COMMON-LISP-USER"
)
```
This method is used to render response requests to `/openrpc.json` handle of your [`api`][5d14].
There is also a second generic-function which transform class instance into simple datastructures
according to a scheme. For example, here is how we can serialize our pet:
```
CL-USER> (openrpc-server:transform-result
(make-instance 'pet :name "Bobik"))
(SERAPEUM:DICT
"name" "Bobik"
)
CL-USER> (openrpc-server:transform-result
(make-instance 'pet
:name "Bobik"
:tag "the dog"))
(SERAPEUM:DICT
"name" "Bobik"
"tag" "the dog"
)
```
#### Returning Lists
To return result as a list of objects of some kind, use `(:result (list-of pet))` form:
```
(openrpc-server:define-rpc-method list-pets ()
(:result (list-of pet))
(retrieve-all-pets))
```
#### Paginated Results
Sometimes your system might operate on a lot of objects and you don't want to return all of them at once.
For this case, framework supports a [keyset pagination][7ba8]. To use
it, your method should accept `LIMIT` argument and `PAGE-KEY` argument. And if there are more results, than
method should return as a second value the page key for retrieving the next page.
In this simplified example, we'll return `(list 1 2 3)` for the first page, `(list 4 5 6)` for the second and
`(list 7 8)` for the third. Pay attention how `VALUES` form is used for first two pages but omitted for the third:
```
(openrpc-server:define-rpc-method list-pets (&key (limit 3) page-key)
(:param limit integer)
(:param page-key integer)
(:result (paginated-list-of integer))
(cond
((null page-key)
(values (list 1 2 3)
3))
((= page-key 3)
(values (list 4 5 6)
6))
(t
(list 7 8))))
```
Of cause, in the real world application, you should use `PAGE-KEY` and `LIMIT` arguments in the `WHERE` `SQL` clause.
### Using Clack to Start Server
Framework is based on Clack. Use [`make-clack-app`][1d3d] to create an application suitable for serving with `CLACK:CLACKUP`.
Then just start the web application as usual.
```
(clack:clackup (make-clack-app)
:address interface
:port port)
```
Also, you might use any Lack middlewares. For example, here is how "mount" middleware can be used
to make [`api`][5d14] work on `/api/` `URL` path, while the main application is working on other `URL` paths:
```
(defparameter *app*
(lambda (env)
'(200 (:content-type "text/plain") ("Hello, World!"))))
(clack:clackup
(lambda (app)
(funcall (lack.util:find-middleware :mount)
app
"/api"
(make-clack-app)))
*app*)
```
### OpenRPC Spec
The key feature of the framework, is an automatic `OpenRPC spec` generation.
When you have your [`api`][5d14] up and running, spec will be available on `/openrpc.json` path.
For our example project it will looks like:
```json
{
"methods": [
{
"name": "rpc.discover",
"params": [],
"result": {
"name": "OpenRPC Schema",
"schema": {
"$ref": "https://raw.githubusercontent.com/open-rpc/meta-schema/master/schema.json"
}
}
},
{
"name": "list-pets",
"params": [
{
"name": "page-key",
"schema": {
"type": "integer"
}
},
{
"name": "limit",
"schema": {
"type": "integer"
}
}
],
"result": {
"name": "list-pets-result",
"schema": {
"type": "object",
"properties": {
"items": {
"type": "array",
...
```
### API
#### [class](036c) `openrpc-server/api:api` ()
#### [variable](c65b) `openrpc-server/api:*current-api*` -unbound-
Points to a current [`api`][5d14] object when processing any `RPC` method.
#### [macro](bad8) `openrpc-server/api:define-api` (NAME &KEY (TITLE "Default API") (VERSION "0.1.0")) &BODY SLOTS
#### [reader](d194) `openrpc-server/api:api-methods` (api) (= (make-hash-table :test 'equal))
Returns a hash-table containing meta-information about all [`api`][5d14] methods.
Returned hash-table has key strings having methods names and internal
objects of class `method-info` as values. I'm not sure if we need to
export functions to manipulate with method info objects manually.
Use [`openrpc-server/method:define-rpc-method`][b2e4] macro to add or update `RPC` methods.
#### [reader](09ad) `openrpc-server/api:api-title` (api) (:TITLE = "Default API")
Returns a title of the [`api`][5d14].
#### [reader](18aa) `openrpc-server/api:api-version` (api) (:version = "0.1.0")
Returns a version of the [`api`][5d14].
#### [macro](69f9) `openrpc-server/method:define-rpc-method` name args &body body
Macro to define `RPC` method.
All arguments should have corresponding (:param arg type) form in the `BODY`.
Also, there should be one (:result type) form in the `BODY`.
#### [generic-function](e9c0) `openrpc-server/interface:type-to-schema` type
This method is called for all types for which [`primitive-type-p`][edf5] generic-function
returns `NIL`.
It should return as hash-table with `JSON-SCHEMA` corresponding to type. Keys of the dictionary should
be strings. It is convenient to use Serapeum's `DICT` macro for building the result.
#### [generic-function](e145) `openrpc-server/interface:transform-result` object
Prepares object for serialization before responding to `RPC` call.
Result should be list, hash-map or a value of primitive type.
#### [generic-function](5bfd) `openrpc-server/interface:primitive-type-p` type
Should return t for type if it's name matched to simple types supported by [JSON-SCHEMA][686b].
Argument `TYPE` is a symbol.
#### [generic-function](8f78) `openrpc-server/interface:make-info` api
Returns a basic information about `API` for [info section][5f59] of Open`RPC` spec.
#### [function](9048) `openrpc-server/errors:return-error` message &key (code -1) (error-class 'jsonrpc/errors:jsonrpc-callback-error)
Raises an error to interrupt processing and return status to the caller.
#### [generic-function](f41b) `openrpc-server/clack:make-clack-app` api &key http websocket indent-json
Should return an app suitable for passing to clackup.
You can define a method to redefine application.
But to add middlewares it is more convenient to define a method for
[`app-middlewares`][a0d7] generic-function.
#### [generic-function](4dfb) `openrpc-server/clack:app-middlewares` api
Should return an plist of middlewared to be applied to the Clack application.
Keys should be a keyword with middleware name. And value is a function accepting
a Clack application as a single argument and returning a new application.
Middlewares are applied to the app from left to right. This makes it possible to
define an :around method which will inject or replace a middleware or original app.
Default method defines two middlewares with keys `:CORS` and `:PROMETHEUS`.
(Prometheus middleware works on `SBCL` but not on `CCL`).
To wrap these middlewares, add your middlewares to the end of the list.
To add your middleware inside the stack - push it to the front.
#### [function](0bc8) `openrpc-server/clack:debug-on`
#### [function](99e2) `openrpc-server/clack:debug-off`
#### [generic-function](1f7a) `openrpc-server/interface:slots-to-exclude` type
You can define a method for this generic function to exclude some slots from being shown in the `JSON` schema.
Pay attention that this generic-function is called with class not with objects to be serialized.
We need this because at the moment of generation [`api`][5d14] methods and Open`RPC` spec we know nothing about
objects except their classes.
Methods of this function should return a list of strings. Given slots will be excluded from the spec
and will not be serialized. Strings are compared in case-insensitive mode.
## Client
### OPENRPC-CLIENT ASDF System Details
* Description: Open`RPC` client implementation for Common Lisp.
* Licence: `BSD`
* Author: Alexander Artemenko
* Homepage: [https://40ants.com/openrpc/][348e]
* Source control: [GIT][76b5]
* Depends on: [alexandria][8236], [closer-mop][61a4], [dexador][8347], [jsonrpc][a9bd], [kebab][5186], [log4cl][7f8b], [serapeum][c41d], [str][ef7f], [usocket][636b], [yason][aba2]
[`openrpc-client`][4c76] `ASDF` system provides a way to build `CL` classes and methods for working with `JSON-RPC` `API`.
All you need is to give it an `URL` and all code will be created in compile-time as a result of macro-expansion.
### Generating
For example, this macro call:
```
(generate-client petshop
"http://localhost:8000/openrpc.json")
```
Will generate the whole bunch of classes and methods:
```
(defclass petshop (jsonrpc/client:client) nil)
(defun make-petshop () (make-instance 'petshop))
(defmethod describe-object ((openrpc-client/core::client petshop) stream)
(format stream "Supported RPC methods:~2%")
(format stream "- ~S~%" '(rpc-discover))
(format stream "- ~S~%"
'(list-pets &key (page-key nil page-key-given-p)
(limit nil limit-given-p)))
(format stream "- ~S~%" '(create-pet (name string) (tag string)))
(format stream "- ~S~%" '(get-pet (id integer))))
(defclass pet nil
((id :initform nil :initarg :id :reader pet-id)
(name :initform nil :initarg :name :reader pet-name)
(tag :initform nil :initarg :tag :reader pet-tag)))
(defmethod print-object ((openrpc-client/core::obj pet) stream)
(print-unreadable-object (openrpc-client/core::obj stream :type t)
(format stream " ~A=~S" 'id (pet-id openrpc-client/core::obj))
(format stream " ~A=~S" 'name (pet-name openrpc-client/core::obj))
(format stream " ~A=~S" 'tag (pet-tag openrpc-client/core::obj))))
(defmethod rpc-discover ((openrpc-client/core::client petshop))
...)
(defmethod list-pets
((openrpc-client/core::client petshop)
&key (page-key nil page-key-given-p) (limit nil limit-given-p))
...)
(defmethod create-pet
((openrpc-client/core::client petshop) (name string) (tag string))
...)
(defmethod get-pet ((openrpc-client/core::client petshop) (id integer))
...)
```
### Using
When client is generated, you need to make an instance of it and to connect
it to the server:
```
(let ((cl (make-petshop)))
(jsonrpc:client-connect cl :url "http://localhost:8000/" :mode :http)
cl)
```
You can use any transport, supported by `JSONRPC` library.
`DESCRIBE-OBJECT` method is defined for a client, so you might see which methods are supported right in the `REPL`:
```common-lisp-repl
OPENRPC-EXAMPLE/CLIENT> (defvar *client* (make-test-client))
#
OPENRPC-EXAMPLE/CLIENT> (describe *client*)
Supported RPC methods:
- (RPC-DISCOVER)
- (LIST-PETS &KEY (PAGE-KEY NIL PAGE-KEY-GIVEN-P)
(LIMIT NIL LIMIT-GIVEN-P))
- (CREATE-PET (NAME STRING) (TAG STRING))
- (GET-PET (ID INTEGER))
```
And then to call these methods as usually you do in Common Lisp. Pay attention, that
the library returns not `JSON` dictionaries, but ready to use `CL` class instances:
```common-lisp-repl
OPENRPC-EXAMPLE/CLIENT> (create-pet *client* "Bobik" "the dog")
#
OPENRPC-EXAMPLE/CLIENT> (create-pet *client* "Murzik" "the cat")
#
OPENRPC-EXAMPLE/CLIENT> (create-pet *client* "Homa" "the hamster")
#
```
Now, pay attention how pagination does work.
```common-lisp-repl
OPENRPC-EXAMPLE/CLIENT> (list-pets *client* :limit 2)
(#
#)
#
```
This call has returned a list of objects as the first value and a closure, which can
be called to retrive the next page. Let's retrieve it now!
```common-lisp-repl
OPENRPC-EXAMPLE/CLIENT> (funcall #v167:1)
(#)
```
Now this is the last page and there is now a closure to retrieve the next page. Learn more how
to implement pagination on server-side in the [`Paginated Results`][5c31] section.
### [macro](7cbd) `openrpc-client/core:generate-client` class-name url-or-path &key (export-symbols t)
Generates Common Lisp client by Open`RPC` spec.
`CLASS-NAME` is the name of a `API` class. Also, a corresponding `MAKE`- function
is created.
`URL-OR-PATH` argument could be a string with `HTTP` `URL` of a spec, or a pathname
if a spec should be read from the disc.
## Our Ask...
If you use this or find value in it, please consider contributing in one or more of the following ways:
1. Sponsor project at [Patreon][2180] or [Boosty][ae59] and make a contribution.
2. Star it!
3. Share posts about it in social networks!
4. Fix an issue.
5. Add a feature (post a proposal in an issue first!).
## Contributors
These people have contributed to Open`RPC`. I'm so grateful to them!
* [Kilian M. Haemmerle][5863]
[348e]: https://40ants.com/openrpc/
[4c76]: https://40ants.com/openrpc/#x-28-23A-28-2814-29-20BASE-CHAR-20-2E-20-22openrpc-client-22-29-20ASDF-2FSYSTEM-3ASYSTEM-29
[24be]: https://40ants.com/openrpc/#x-28-23A-28-2814-29-20BASE-CHAR-20-2E-20-22openrpc-server-22-29-20ASDF-2FSYSTEM-3ASYSTEM-29
[5d14]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FAPI-3AAPI-20CLASS-29
[a0d7]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FCLACK-3AAPP-MIDDLEWARES-20GENERIC-FUNCTION-29
[1d3d]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FCLACK-3AMAKE-CLACK-APP-20GENERIC-FUNCTION-29
[5c31]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FDOCS-3A-3A-40PAGINATION-2040ANTS-DOC-2FLOCATIVES-3ASECTION-29
[edf5]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FINTERFACE-3APRIMITIVE-TYPE-P-20GENERIC-FUNCTION-29
[4de0]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FINTERFACE-3ATYPE-TO-SCHEMA-20GENERIC-FUNCTION-29
[b2e4]: https://40ants.com/openrpc/#x-28OPENRPC-SERVER-2FMETHOD-3ADEFINE-RPC-METHOD-20-2840ANTS-DOC-2FLOCATIVES-3AMACRO-29-29
[ae59]: https://boosty.to/40ants
[76b5]: https://github.com/40ants/openrpc
[4bbd]: https://github.com/40ants/openrpc/actions
[7cbd]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/client/core.lisp#L522
[c65b]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/api.lisp#L14
[036c]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/api.lisp#L18
[d194]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/api.lisp#L19
[09ad]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/api.lisp#L27
[18aa]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/api.lisp#L31
[bad8]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/api.lisp#L39
[0bc8]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/clack.lisp#L181
[99e2]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/clack.lisp#L186
[f41b]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/clack.lisp#L67
[4dfb]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/clack.lisp#L74
[9048]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/errors.lisp#L9
[8f78]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/interface.lisp#L167
[e145]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/interface.lisp#L21
[5bfd]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/interface.lisp#L56
[1f7a]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/interface.lisp#L72
[e9c0]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/interface.lisp#L85
[69f9]: https://github.com/40ants/openrpc/blob/d200d1687dce5f1350d0eee29b5d278d87f596a5/server/method.lisp#L313
[c597]: https://github.com/cxxxr/jsonrpc
[75f7]: https://github.com/fukamachi/clack
[5863]: https://github.com/kilianmh
[686b]: https://json-schema.org/
[8236]: https://quickdocs.org/alexandria
[087e]: https://quickdocs.org/clack-cors
[babd]: https://quickdocs.org/clack-prometheus
[61a4]: https://quickdocs.org/closer-mop
[8347]: https://quickdocs.org/dexador
[a9bd]: https://quickdocs.org/jsonrpc
[5186]: https://quickdocs.org/kebab
[6a02]: https://quickdocs.org/lack-request
[3ad9]: https://quickdocs.org/lambda-fiddle
[46a1]: https://quickdocs.org/local-time
[7f8b]: https://quickdocs.org/log4cl
[691c]: https://quickdocs.org/log4cl-extras
[c41d]: https://quickdocs.org/serapeum
[ef7f]: https://quickdocs.org/str
[636b]: https://quickdocs.org/usocket
[4f50]: https://quickdocs.org/websocket-driver
[aba2]: https://quickdocs.org/yason
[3160]: https://spec.open-rpc.org/
[5f59]: https://spec.open-rpc.org/#info-object
[7ba8]: https://use-the-index-luke.com/no-offset
[2180]: https://www.patreon.com/bePatron?u=33868637
* * *
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