Merge pull request #3 from mduesterhoeft/convenience

Add more convenience methods to request and response

Author: mduesterhoeft

src/main/kotlin/com/github/mduesterhoeft/router/APIGatewayProxyEventExtensions.kt

@@ -2,6 +2,7 @@ package com.github.mduesterhoeft.router
 
 import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyRequestEvent
 import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent
+import java.net.URI
 import java.util.Base64
 
 fun APIGatewayProxyRequestEvent.acceptHeader() = getHeaderCaseInsensitive("accept")
@@ -13,6 +14,48 @@ fun APIGatewayProxyRequestEvent.getHeaderCaseInsensitive(httpHeader: String): St
 fun APIGatewayProxyResponseEvent.getHeaderCaseInsensitive(httpHeader: String): String? =
     getCaseInsensitive(httpHeader, headers)
 
+fun GET() = APIGatewayProxyRequestEvent().withHttpMethod("get").withHeaders(mutableMapOf())
+fun GET(path: String) = GET().withPath(path)
+fun POST() = APIGatewayProxyRequestEvent().withHttpMethod("post").withHeaders(mutableMapOf())
+fun POST(path: String) = POST().withPath(path)
+fun PUT() = APIGatewayProxyRequestEvent().withHttpMethod("put").withHeaders(mutableMapOf())
+fun PUT(path: String) = PUT().withPath(path)
+fun PATCH() = APIGatewayProxyRequestEvent().withHttpMethod("patch").withHeaders(mutableMapOf())
+fun PATCH(path: String) = PATCH().withPath(path)
+fun DELETE() = APIGatewayProxyRequestEvent().withHttpMethod("delete").withHeaders(mutableMapOf())
+fun DELETE(path: String) = DELETE().withPath(path)
+
+/**
+ * Get a URI that can be used as location header for responses.
+ * The host is taken from the Host header.
+ * The protocol is taken from the x-forwarded-proto.
+ * The port is taken from the x-forwarded-port header. Standard ports are omitted.
+ */
+fun APIGatewayProxyRequestEvent.location(path: String): URI {
+    val host = getHeaderCaseInsensitive("host")?:"localhost"
+    val proto = getHeaderCaseInsensitive("x-forwarded-proto")?:"http"
+    val portPart = getHeaderCaseInsensitive("x-forwarded-port")
+        ?.let {
+            when {
+                proto == "https" && it == "443" -> null
+                proto == "http" && it == "80" -> null
+                else -> ":$it"
+            }
+        }?: ""
+    return URI("$proto://$host$portPart/${path.removePrefix("/")}")
+}
+
+fun APIGatewayProxyRequestEvent.withHeader(name: String, value: String) =
+    this.also { if (headers == null) headers = mutableMapOf() }.also { headers[name] = value }
+
+fun APIGatewayProxyResponseEvent.withHeader(name: String, value: String) =
+    this.also { if (headers == null) headers = mutableMapOf() }.also { headers[name] = value }
+
+fun APIGatewayProxyResponseEvent.withLocationHeader(request: APIGatewayProxyRequestEvent, path: String) =
+    this.also { if (headers == null) headers = mutableMapOf() }.also { headers["location"] = request.location(path).toString() }
+
+fun APIGatewayProxyResponseEvent.location() = getHeaderCaseInsensitive("location")
+
 private fun getCaseInsensitive(key: String, map: Map<String, String>): String? =
     map.entries
         .firstOrNull { it.key.toLowerCase() == key.toLowerCase() }

src/test/kotlin/com/github/mduesterhoeft/router/APIGatewayProxyEventExtensionsTest.kt

@@ -0,0 +1,59 @@
+package com.github.mduesterhoeft.router
+
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent
+import org.assertj.core.api.BDDAssertions.then
+import org.junit.jupiter.api.Test
+
+class APIGatewayProxyEventExtensionsTest {
+
+    @Test
+    fun `should add location header`() {
+
+        val request = GET()
+            .withHeader("Host", "example.com")
+            .withHeader("X-Forwarded-Proto", "http")
+            .withHeader("X-Forwarded-Port", "8080")
+
+        val response = APIGatewayProxyResponseEvent()
+            .withLocationHeader(request, "/some/path")
+
+        then(response.location()).isEqualTo("http://example.com:8080/some/path")
+    }
+
+    @Test
+    fun `should add location header with default host and proto and without port`() {
+
+        val request = GET()
+
+        val response = APIGatewayProxyResponseEvent()
+            .withLocationHeader(request, "/some/path")
+
+        then(response.location()).isEqualTo("http://localhost/some/path")
+    }
+
+    @Test
+    fun `should omit default https port`() {
+
+        val request = GET()
+            .withHeader("Host", "example.com")
+            .withHeader("X-Forwarded-Proto", "https")
+            .withHeader("X-Forwarded-Port", "443")
+
+        val location = request.location("some/path")
+
+        then(location.toString()).isEqualTo("https://example.com/some/path")
+    }
+
+    @Test
+    fun `should omit default http port`() {
+
+        val request = GET()
+            .withHeader("Host", "example.com")
+            .withHeader("X-Forwarded-Proto", "http")
+            .withHeader("X-Forwarded-Port", "80")
+
+        val location = request.location("/some/path")
+
+        then(location.toString()).isEqualTo("http://example.com/some/path")
+    }
+}