From 54d9219eabc3c0883ba71bc533e7fc98ff88e3da Mon Sep 17 00:00:00 2001
From: "raphael.marques" <raphael.marques@alan.eu>
Date: Thu, 14 Oct 2021 15:21:59 +0200
Subject: [PATCH] feat: add prefetchMethod option

---
 README.md                      | 18 ++++++++++++++++++
 src/index.tsx                  |  1 +
 src/state/index.tsx            |  3 ++-
 src/state/reducer.ts           |  1 +
 src/utils/useDocumentLoader.ts |  4 ++--
 5 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index a473f63a..cedf0281 100644
--- a/README.md
+++ b/README.md
@@ -173,6 +173,23 @@ MyCustomPNGRenderer.fileLoader = ({
 <br />
 <br />
 
+### Custom pre-fetch HTTP Verb
+
+Some services (such as AWS) provide URLs that works only for one pre-configured verb.
+By default, `react-doc-viewer` fetches document metadata through a `HEAD` request in order to guess its `Content-Type`.
+If you need to have a specific verb for the pre-fetching, use the `prefetchMethod` option on the DocViewer:
+
+```tsx
+import DocViewer, { DocViewerRenderers } from "react-doc-viewer";
+
+<DocViewer
+  prefetchMethod="GET"
+/>;
+```
+
+<br />
+<br />
+
 ### Themed
 
 You can provide a theme object with one or all of the available properties.
@@ -368,6 +385,7 @@ const myHeader: IHeaderOverride = (state, previousDocument, nextDocument) => {
 | config?          | [`IConfig`](#iconfig)           |
 | theme?           | [`ITheme`](#itheme)             |
 | pluginRenderers? | [`DocRenderer[]`](#docrenderer) |
+| prefetchMethod?  | `string`                        |
 
 ---
 
diff --git a/src/index.tsx b/src/index.tsx
index 11c986ff..af6cb9c7 100644
--- a/src/index.tsx
+++ b/src/index.tsx
@@ -23,6 +23,7 @@ export interface DocViewerProps {
   config?: IConfig;
   theme?: ITheme;
   pluginRenderers?: DocRenderer[];
+  prefetchMethod?: string;
 }
 
 const DocViewer: FC<DocViewerProps> = (props) => {
diff --git a/src/state/index.tsx b/src/state/index.tsx
index 1a719230..cad27c55 100644
--- a/src/state/index.tsx
+++ b/src/state/index.tsx
@@ -20,7 +20,7 @@ const DocViewerContext = createContext<{
 }>({ state: initialState, dispatch: () => null });
 
 const AppProvider: FC<DocViewerProps> = (props) => {
-  const { children, documents, config, pluginRenderers } = props;
+  const { children, documents, config, pluginRenderers, prefetchMethod } = props;
 
   const [state, dispatch] = useReducer<MainStateReducer>(mainStateReducer, {
     ...initialState,
@@ -28,6 +28,7 @@ const AppProvider: FC<DocViewerProps> = (props) => {
     currentDocument: documents && documents.length ? documents[0] : undefined,
     config,
     pluginRenderers,
+    prefetchMethod,
   });
 
   // On inital load, and whenever they change,
diff --git a/src/state/reducer.ts b/src/state/reducer.ts
index 64e16ac0..f3e726a0 100644
--- a/src/state/reducer.ts
+++ b/src/state/reducer.ts
@@ -23,6 +23,7 @@ export type IMainState = {
   rendererRect?: DOMRect;
   config?: IConfig;
   pluginRenderers?: DocRenderer[];
+  prefetchMethod?: string;
 };
 
 export const initialState: IMainState = {
diff --git a/src/utils/useDocumentLoader.ts b/src/utils/useDocumentLoader.ts
index 52d5f9a5..701ded68 100644
--- a/src/utils/useDocumentLoader.ts
+++ b/src/utils/useDocumentLoader.ts
@@ -19,7 +19,7 @@ export const useDocumentLoader = (): {
   CurrentRenderer: DocRenderer | null | undefined;
 } => {
   const { state, dispatch } = useContext(DocViewerContext);
-  const { currentFileNo, currentDocument } = state;
+  const { currentFileNo, currentDocument, prefetchMethod } = state;
 
   const { CurrentRenderer } = useRendererSelector();
 
@@ -33,7 +33,7 @@ export const useDocumentLoader = (): {
       const controller = new AbortController();
       const { signal } = controller;
 
-      fetch(documentURI, { method: "HEAD", signal }).then((response) => {
+      fetch(documentURI, { method: prefetchMethod || "HEAD", signal }).then((response) => {
         const contentTypeRaw = response.headers.get("content-type");
         const contentTypes = contentTypeRaw?.split(";") || [];
         const contentType = contentTypes.length ? contentTypes[0] : undefined;