From d9aff1fdeba32fa2b956b8df7d479cc4d627a6ce Mon Sep 17 00:00:00 2001
From: Daniel Parker <dparker.tech@gmail.com>
Date: Mon, 22 Oct 2018 11:56:03 -0500
Subject: [PATCH] [jsonwebtoken] FIX: Better typing to replace 'Function'

---
 types/jsonwebtoken/index.d.ts            | 28 ++++++++++++++++++++++--
 types/jsonwebtoken/jsonwebtoken-tests.ts |  2 +-
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/types/jsonwebtoken/index.d.ts b/types/jsonwebtoken/index.d.ts
index ac2762dbd9..1c3cda40ba 100644
--- a/types/jsonwebtoken/index.d.ts
+++ b/types/jsonwebtoken/index.d.ts
@@ -90,6 +90,30 @@ export interface SignCallback {
     (err: Error, encoded: string): void;
 }
 
+
+export interface JwtHeader {
+    alg: string
+    typ?: string
+    kid?: string
+    jku?: string
+    x5u?: string
+    x5t?: string
+}
+
+export interface SigningKeyCallback {
+    (
+        err: any,
+        signingKey?: Secret,
+    ): void
+}
+
+export interface GetPublicKeyOrSecret {
+    (
+        header: JwtHeader,
+        callback: SigningKeyCallback
+    ): void;
+}
+
 export type Secret = string | Buffer | { key: string; passphrase: string };
 
 /**
@@ -150,12 +174,12 @@ export declare function verify(
  */
 export declare function verify(
     token: string,
-    secretOrPublicKey: string | Buffer | Function,
+    secretOrPublicKey: string | Buffer | GetPublicKeyOrSecret,
     callback?: VerifyCallback,
 ): void;
 export declare function verify(
     token: string,
-    secretOrPublicKey: string | Buffer | Function,
+    secretOrPublicKey: string | Buffer | GetPublicKeyOrSecret,
     options?: VerifyOptions,
     callback?: VerifyCallback,
 ): void;
diff --git a/types/jsonwebtoken/jsonwebtoken-tests.ts b/types/jsonwebtoken/jsonwebtoken-tests.ts
index 6f9977995e..d1d51014fe 100644
--- a/types/jsonwebtoken/jsonwebtoken-tests.ts
+++ b/types/jsonwebtoken/jsonwebtoken-tests.ts
@@ -84,7 +84,7 @@ jwt.verify(token, cert, function(err, decoded) {
 });
 
 // verify a token assymetric with async key fetch function
-function getKey(header: Object, callback: Function) {
+function getKey(header: jwt.JwtHeader, callback: jwt.SigningKeyCallback) {
     cert = fs.readFileSync("public.pem");
 
     callback(null, cert);