Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/walmartlabs/lacinia-pedestal

Expose Lacinia GraphQL as Pedestal endpoints
https://github.com/walmartlabs/lacinia-pedestal

clojure graphql http pedestal

Last synced: 4 days ago
JSON representation

Expose Lacinia GraphQL as Pedestal endpoints

Awesome Lists containing this project

README 

        
# com.walmartlabs/lacinia-pedestal



[![Clojars Project](https://img.shields.io/clojars/v/com.walmartlabs/lacinia-pedestal.svg)](https://clojars.org/com.walmartlabs/lacinia-pedestal)

[![CI](https://github.com/walmartlabs/lacinia-pedestal/actions/workflows/config.yml/badge.svg)](https://github.com/walmartlabs/lacinia-pedestal/actions/workflows/config.yml)

[![API DOCS](https://cljdoc.org/badge/com.walmartlabs/lacinia-pedestal)](https://cljdoc.org/d/com.walmartlabs/lacinia-pedestal)



A library that adds the

[Pedestal](https://github.com/pedestal/pedestal) underpinnings needed when exposing

[Lacinia](https://github.com/walmartlabs/lacinia) as an HTTP endpoint.



Lacinia-Pedestal also supports GraphQL subscriptions, using the same protocol

as [Apollo GraphQL](https://github.com/apollographql/subscriptions-transport-ws).



[Lacinia-Pedestal Manual](http://lacinia-pedestal.readthedocs.io/en/latest/) |

[API Documentation](http://walmartlabs.github.io/apidocs/lacinia-pedestal/)



## Usage



For a basic Pedestal server, simply supply a compiled Lacinia schema to

the `com.walmartlabs.lacinia.pedestal2/default-service` function to

generate a service, then invoke `io.pedestal.http/create-server` and `/start`.



```clojure

(ns graphql-demo.server

  (:require [io.pedestal.http :as http]

            [com.walmartlabs.lacinia.pedestal2 :as lp]

            [com.walmartlabs.lacinia.schema :as schema]

            [com.walmartlabs.lacinia.util :as util]))



(def hello-schema 

  (-> {:objects 

        {:Query

         {:fields

            ;; String is quoted here; in EDN the quotation is not required 

            ;; You could also use :String

            {:hello {:type 'String}}}}}

       (util/inject-resolvers {:Query/hello (constantly "hello")})

       (schema/compile)))



;; Use default options:

(def service (lp/default-service hello-schema nil))



;; This is an adapted service map, that can be started and stopped.

;; From the REPL you can call http/start and http/stop on this service:

(defonce runnable-service (http/create-server service))



(defn -main

  [& args]

  (println "\nCreating your server...")

  (http/start runnable-service))

```



Lacinia will handle POST requests at the `/api` endpoint:



```bash

$ curl localhost:8888/api -X POST -H "content-type: application/json" -d '{"query": "{ hello }"}'

{"data":{"hello":"world"}}

```



You can also access the GraphQL IDE at `http://localhost:8888/ide`.



## Development Mode



When developing an application, it is desirable to be able to change the schema

without restarting.

Lacinia-Pedestal supports this: in the above example, the schema passed to

`default-service` could be a _function_ that returns the compiled schema.

It could even be a Var containing the function that returns the compiled schema.



In this way, the Pedestal stack continues to run, but each request rebuilds

the compiled schema based on the latest code you've loaded into the REPL.



## Beyond default-server



`default-service` is intentionally limited, and exists only to help you get started.

Once you start adding anything more complicated, such as authentication, or supporting

multiple schemas (or schema versions) at different paths, 

you will want to simply create your routes and server in your own code,

using the building-blocks provided by `com.walmartlabs.lacinia.pedestal2`.



### GraphiQL



The GraphiQL packaged inside the library is built using `npm`, from

version `1.7.1`.



If you are including lacinia-pedestal via Git coordinate (rather than a published version

of the library by using a :mvn/version coordinate), then the library will need to be prepped for use 

via `clj -X:deps prep`.

 

The prep action for lacinia-pedestal requires that you have `npm` installed.  

The prep action generates the CSS and JavaScript files that are used

to execute GraphiQL.



## License



Copyright © 2017-2024 Walmart



Distributed under the Apache Software License 2.0.



GraphiQL has its own [license](https://raw.githubusercontent.com/graphql/graphiql/master/LICENSE).