CORS on Spring Boot Applications in Kotlin

The WebFilter in the Kotlin code block below enables CORS on Spring Boot applications using the WebFlux starter.

	import org.springframework.http.HttpMethod
	import org.springframework.http.HttpStatus
	import org.springframework.stereotype.Component
	import org.springframework.web.server.ServerWebExchange
	import org.springframework.web.server.WebFilter
	import org.springframework.web.server.WebFilterChain
	import reactor.core.publisher.Mono

	@Component
	class CorsFilter : WebFilter {
	override fun filter(ctx: ServerWebExchange?, chain: WebFilterChain?): Mono<Void> {
	if (ctx != null) {
	ctx.response.headers.add("Access-Control-Allow-Origin", "*")
	ctx.response.headers.add("Access-Control-Allow-Methods", "GET, PUT, POST, DELETE, OPTIONS")
	ctx.response.headers.add("Access-Control-Allow-Headers", "DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range")
	if (ctx.request.method == HttpMethod.OPTIONS) {
	ctx.response.headers.add("Access-Control-Max-Age", "1728000")
	ctx.response.statusCode = HttpStatus.NO_CONTENT
	return Mono.empty()
	} else {
	ctx.response.headers.add("Access-Control-Expose-Headers", "DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range")
	return chain?.filter(ctx) ?: Mono.empty()
	}
	} else {
	return chain?.filter(ctx) ?: Mono.empty()
	}
	}
	}

view raw CorsFilter.kt hosted with ❤ by GitHub

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