From 34c894c5269872a81f7f6ee084ef2d1a366cd04c Mon Sep 17 00:00:00 2001
From: Michael Lynch <git@mtlynch.io>
Date: Fri, 12 Aug 2022 21:13:56 -0400
Subject: [PATCH 1/2] Add a plaintext response for guest uploads

---
 handlers/upload.go      | 34 +++++++++++++++++++++++++++++-----
 handlers/upload_test.go |  1 +
 2 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/handlers/upload.go b/handlers/upload.go
index 9f4eb34b..9e66466d 100644
--- a/handlers/upload.go
+++ b/handlers/upload.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"os"
 	"time"
 
 	"github.com/gorilla/mux"
@@ -152,11 +153,18 @@ func (s Server) guestEntryPost() http.HandlerFunc {
 			return
 		}
 
-		w.Header().Set("Content-Type", "application/json")
-		if err := json.NewEncoder(w).Encode(EntryPostResponse{
-			ID: string(id),
-		}); err != nil {
-			panic(err)
+		if clientAcceptsJson(r) {
+			w.Header().Set("Content-Type", "application/json")
+			if err := json.NewEncoder(w).Encode(EntryPostResponse{
+				ID: string(id),
+			}); err != nil {
+				panic(err)
+			}
+		} else {
+			w.Header().Set("Content-Type", "text/plain")
+			if _, err := fmt.Fprintf(w, "%s/!%s\r\n", baseURLFromRequest(r), string(id)); err != nil {
+				log.Fatalf("failed to write HTTP response: %v", err)
+			}
 		}
 	}
 }
@@ -302,3 +310,19 @@ func parseExpirationFromRequest(r *http.Request) (types.ExpirationTime, error) {
 func mibToBytes(i int64) int64 {
 	return i << 20
 }
+
+func clientAcceptsJson(r *http.Request) bool {
+	accepts := r.Header.Get("Accepts")
+	return accepts == "*/*" || accepts == "application/json"
+}
+
+func baseURLFromRequest(r *http.Request) string {
+	var scheme string
+	// If we're running behind a proxy, assume that it's a TLS proxy.
+	if r.TLS != nil || os.Getenv("PS_BEHIND_PROXY") != "" {
+		scheme = "https"
+	} else {
+		scheme = "http"
+	}
+	return fmt.Sprintf("%s://%s", scheme, r.Host)
+}
diff --git a/handlers/upload_test.go b/handlers/upload_test.go
index 1bf67e29..144fe1ef 100644
--- a/handlers/upload_test.go
+++ b/handlers/upload_test.go
@@ -391,6 +391,7 @@ func TestGuestUpload(t *testing.T) {
 				t.Fatal(err)
 			}
 			req.Header.Add("Content-Type", contentType)
+			req.Header.Add("Accepts", "application/json")
 
 			w := httptest.NewRecorder()
 			s.Router().ServeHTTP(w, req)

From 9f8c3ddb8db3a19f7282cd82874204cbc5499ac1 Mon Sep 17 00:00:00 2001
From: Michael Lynch <git@mtlynch.io>
Date: Fri, 12 Aug 2022 21:20:21 -0400
Subject: [PATCH 2/2] Fix Accept header name

---
 handlers/upload.go      | 2 +-
 handlers/upload_test.go | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/handlers/upload.go b/handlers/upload.go
index 9e66466d..2b92fb0a 100644
--- a/handlers/upload.go
+++ b/handlers/upload.go
@@ -312,7 +312,7 @@ func mibToBytes(i int64) int64 {
 }
 
 func clientAcceptsJson(r *http.Request) bool {
-	accepts := r.Header.Get("Accepts")
+	accepts := r.Header.Get("Accept")
 	return accepts == "*/*" || accepts == "application/json"
 }
 
diff --git a/handlers/upload_test.go b/handlers/upload_test.go
index 144fe1ef..2cd871ee 100644
--- a/handlers/upload_test.go
+++ b/handlers/upload_test.go
@@ -391,7 +391,7 @@ func TestGuestUpload(t *testing.T) {
 				t.Fatal(err)
 			}
 			req.Header.Add("Content-Type", contentType)
-			req.Header.Add("Accepts", "application/json")
+			req.Header.Add("Accept", "application/json")
 
 			w := httptest.NewRecorder()
 			s.Router().ServeHTTP(w, req)