From 26f97645b98e03e63e9501c30a7d4267747b9171 Mon Sep 17 00:00:00 2001
From: Rusty Conover <rusty@conover.me>
Date: Mon, 21 Jun 2021 16:51:40 -0400
Subject: [PATCH] Feature: add full response typing for status code, data and
 headers.

This commit adds additional type information to the route's response
object that allows types to be created that express the combination
of status code, data and headers for each response.

This type information can be used to "narrow" a response type based on
an HTTP status code. This narrowing is useful since it can prevent type
mismatches where a status code is presumed to have one type but in actuality
it returns another.

Additionally, response headers are now associated with data types and status
codes rather than being free form.

A caveat right now is that only there are no response codes like 3XX or
5XX, every code must be explicitly listed.
---
 src/routes.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/src/routes.js b/src/routes.js
index 787dfb4e..2beb1a0f 100644
--- a/src/routes.js
+++ b/src/routes.js
@@ -2,6 +2,7 @@ const _ = require("lodash");
 const {
   types,
   parseSchema,
+  getType,
   getRefType,
   getInlineParseContent,
   checkAndAddNull,
@@ -475,6 +476,21 @@ const getResponseBodyInfo = (routeInfo, routeParams, parsedSchemas) => {
     (response) => !response.isSuccess && response.type !== TS_KEYWORDS.ANY,
   );
 
+  const handleResponseHeaders = (src) => {
+    if (!src) {
+      return "headers: {},";
+    }
+    const headerTypes = Object.fromEntries(
+      Object.entries(src).map(([k, v]) => {
+        return [k, getType(v)];
+      }),
+    );
+    const r = `headers: { ${Object.entries(headerTypes)
+      .map(([k, v]) => `"${k}": ${v}`)
+      .join(",")} },`;
+    return r;
+  };
+
   return {
     contentTypes,
     responses: responseInfos,
@@ -486,6 +502,19 @@ const getResponseBodyInfo = (routeInfo, routeParams, parsedSchemas) => {
       schemas: errorResponses,
       type: _.uniq(errorResponses.map((response) => response.type)).join(" | ") || TS_KEYWORDS.ANY,
     },
+    full: {
+      types:
+        responseInfos
+          .map(
+            (response) => `{
+      data: ${response.type}, status: ${response.status}, statusCode: ${
+              response.status
+            }, statusText: "${response.description}", ${handleResponseHeaders(
+              response.headers,
+            )} config: {} }`,
+          )
+          .join(" | ") || TS_KEYWORDS.ANY,
+    },
   };
 };
 
@@ -685,6 +714,7 @@ const parseRoutes = ({
               contentTypes: responseBodyInfo.contentTypes,
               type: responseBodyInfo.success.type,
               errorType: responseBodyInfo.error.type,
+              fullTypes: responseBodyInfo.full.types,
             },
             raw: rawRouteInfo,
           };