Implemented logging responses

rest/fints4kRest/src/main/kotlin/net/dankito/banking/fints/rest/LoggingFilter.kt

@@ -0,0 +1,58 @@
+package net.dankito.banking.fints.rest
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import org.slf4j.LoggerFactory
+import javax.inject.Inject
+import javax.ws.rs.container.ContainerRequestContext
+import javax.ws.rs.container.ContainerResponseContext
+import javax.ws.rs.container.ContainerResponseFilter
+import javax.ws.rs.core.Response
+import javax.ws.rs.ext.Provider
+
+
+@Provider
+class LoggingFilter : ContainerResponseFilter {
+
+    companion object {
+        private val log = LoggerFactory.getLogger(LoggingFilter::class.java)
+    }
+
+
+    @Inject
+    internal lateinit var mapper: ObjectMapper
+
+
+    override fun filter(requestContext: ContainerRequestContext, responseContext: ContainerResponseContext) {
+        if (responseContext.statusInfo.family != Response.Status.Family.SUCCESSFUL) {
+            log.warn("Request ${geRequestUrl(requestContext)} failed: ${getResponseStatus(responseContext)}"
+                    + System.lineSeparator() + getHeadersAsString(responseContext)
+                    + System.lineSeparator() + getBodyAsString(responseContext))
+        }
+        else if (log.isDebugEnabled) {
+            log.debug("Result of request ${geRequestUrl(requestContext)}: ${getResponseStatus(responseContext)}"
+                    + System.lineSeparator() + getHeadersAsString(responseContext)
+                    + System.lineSeparator() + getBodyAsString(responseContext))
+        }
+    }
+
+    private fun geRequestUrl(requestContext: ContainerRequestContext): String {
+        return "${requestContext.request.method} ${requestContext.uriInfo.requestUri}"
+    }
+
+    private fun getResponseStatus(responseContext: ContainerResponseContext): String {
+        return "${responseContext.status} ${responseContext.statusInfo.reasonPhrase}"
+    }
+
+    private fun getHeadersAsString(responseContext: ContainerResponseContext): String {
+        return responseContext.stringHeaders.map { header -> "${header.key}: ${header.value}" }.joinToString("\n", "Headers:\n")
+    }
+
+    private fun getBodyAsString(responseContext: ContainerResponseContext): String {
+        if (responseContext.hasEntity()) {
+            return "Body ${responseContext.entityClass.name}:\n" + mapper.writeValueAsString(responseContext.entity)
+        }
+
+        return "<No response body>"
+    }
+
+}