Use response-Headers in the different IPDFStream implementations

Given that the `Headers` functionality is now available in all browsers/environments that we support, [see MDN](https://developer.mozilla.org/en-US/docs/Web/API/Headers#browser_compatibility), we can utilize "proper" `Headers` in the helper functions that are used to parse the response.

src/display/fetch_stream.js

@@ -127,11 +127,11 @@ class PDFFetchStreamReader {
         this._reader = response.body.getReader();
         this._headersCapability.resolve();
 
-        const getResponseHeader = name => response.headers.get(name);
+        const responseHeaders = response.headers;
 
         const { allowRangeRequests, suggestedLength } =
           validateRangeRequestCapabilities({
-            getResponseHeader,
+            responseHeaders,
             isHttp: stream.isHttp,
             rangeChunkSize: this._rangeChunkSize,
             disableRange: this._disableRange,
@@ -141,7 +141,7 @@ class PDFFetchStreamReader {
         // Setting right content length.
         this._contentLength = suggestedLength || this._contentLength;
 
-        this._filename = extractFilenameFromHeader(getResponseHeader);
+        this._filename = extractFilenameFromHeader(responseHeaders);
 
         // We need to stop reading when range is supported and streaming is
         // disabled.

src/display/network.js

@@ -273,11 +273,20 @@ class PDFNetworkStreamFullRequestReader {
     const fullRequestXhrId = this._fullRequestId;
     const fullRequestXhr = this._manager.getRequestXhr(fullRequestXhrId);
 
-    const getResponseHeader = name => fullRequestXhr.getResponseHeader(name);
+    const responseHeaders = new Headers(
+      fullRequestXhr
+        .getAllResponseHeaders()
+        .trim()
+        .split(/[\r\n]+/)
+        .map(x => {
+          const [key, ...val] = x.split(": ");
+          return [key, val.join(": ")];
+        })
+    );
 
     const { allowRangeRequests, suggestedLength } =
       validateRangeRequestCapabilities({
-        getResponseHeader,
+        responseHeaders,
         isHttp: this._manager.isHttp,
         rangeChunkSize: this._rangeChunkSize,
         disableRange: this._disableRange,
@@ -289,7 +298,7 @@ class PDFNetworkStreamFullRequestReader {
     // Setting right content length.
     this._contentLength = suggestedLength || this._contentLength;
 
-    this._filename = extractFilenameFromHeader(getResponseHeader);
+    this._filename = extractFilenameFromHeader(responseHeaders);
 
     if (this._isRangeSupported) {
       // NOTE: by cancelling the full request, and then issuing range

src/display/network_utils.js

@@ -37,7 +37,7 @@ function createHeaders(isHttp, httpHeaders) {
 }
 
 function validateRangeRequestCapabilities({
-  getResponseHeader,
+  responseHeaders,
   isHttp,
   rangeChunkSize,
   disableRange,
@@ -53,7 +53,7 @@ function validateRangeRequestCapabilities({
     suggestedLength: undefined,
   };
 
-  const length = parseInt(getResponseHeader("Content-Length"), 10);
+  const length = parseInt(responseHeaders.get("Content-Length"), 10);
   if (!Number.isInteger(length)) {
     return returnValues;
   }
@@ -69,11 +69,11 @@ function validateRangeRequestCapabilities({
   if (disableRange || !isHttp) {
     return returnValues;
   }
-  if (getResponseHeader("Accept-Ranges") !== "bytes") {
+  if (responseHeaders.get("Accept-Ranges") !== "bytes") {
     return returnValues;
   }
 
-  const contentEncoding = getResponseHeader("Content-Encoding") || "identity";
+  const contentEncoding = responseHeaders.get("Content-Encoding") || "identity";
   if (contentEncoding !== "identity") {
     return returnValues;
   }
@@ -82,8 +82,8 @@ function validateRangeRequestCapabilities({
   return returnValues;
 }
 
-function extractFilenameFromHeader(getResponseHeader) {
-  const contentDisposition = getResponseHeader("Content-Disposition");
+function extractFilenameFromHeader(responseHeaders) {
+  const contentDisposition = responseHeaders.get("Content-Disposition");
   if (contentDisposition) {
     let filename = getFilenameFromContentDispositionHeader(contentDisposition);
     if (filename.includes("%")) {

src/display/node_stream.js

@@ -305,14 +305,11 @@ class PDFNodeStreamFullReader extends BaseFullReader {
       this._headersCapability.resolve();
       this._setReadableStream(response);
 
-      // Make sure that headers name are in lower case, as mentioned
-      // here: https://nodejs.org/api/http.html#http_message_headers.
-      const getResponseHeader = name =>
-        this._readableStream.headers[name.toLowerCase()];
+      const responseHeaders = new Headers(this._readableStream.headers);
 
       const { allowRangeRequests, suggestedLength } =
         validateRangeRequestCapabilities({
-          getResponseHeader,
+          responseHeaders,
           isHttp: stream.isHttp,
           rangeChunkSize: this._rangeChunkSize,
           disableRange: this._disableRange,
@@ -322,7 +319,7 @@ class PDFNodeStreamFullReader extends BaseFullReader {
       // Setting right content length.
       this._contentLength = suggestedLength || this._contentLength;
 
-      this._filename = extractFilenameFromHeader(getResponseHeader);
+      this._filename = extractFilenameFromHeader(responseHeaders);
     };
 
     this._request = createRequest(this._url, headers, handleResponse);

test/unit/network_utils_spec.js

@@ -84,12 +84,9 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: true,
           isHttp: true,
-          getResponseHeader: headerName => {
-            if (headerName === "Content-Length") {
-              return 8;
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Content-Length": 8,
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -101,12 +98,9 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: false,
           isHttp: false,
-          getResponseHeader: headerName => {
-            if (headerName === "Content-Length") {
-              return 8;
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Content-Length": 8,
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -120,14 +114,10 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: false,
           isHttp: true,
-          getResponseHeader: headerName => {
-            if (headerName === "Accept-Ranges") {
-              return "none";
-            } else if (headerName === "Content-Length") {
-              return 8;
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Accept-Ranges": "none",
+            "Content-Length": 8,
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -141,16 +131,11 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: false,
           isHttp: true,
-          getResponseHeader: headerName => {
-            if (headerName === "Accept-Ranges") {
-              return "bytes";
-            } else if (headerName === "Content-Encoding") {
-              return "gzip";
-            } else if (headerName === "Content-Length") {
-              return 8;
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Accept-Ranges": "bytes",
+            "Content-Encoding": "gzip",
+            "Content-Length": 8,
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -164,16 +149,10 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: false,
           isHttp: true,
-          getResponseHeader: headerName => {
-            if (headerName === "Accept-Ranges") {
-              return "bytes";
-            } else if (headerName === "Content-Encoding") {
-              return null;
-            } else if (headerName === "Content-Length") {
-              return "eight";
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Accept-Ranges": "bytes",
+            "Content-Length": "eight",
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -187,16 +166,10 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: false,
           isHttp: true,
-          getResponseHeader: headerName => {
-            if (headerName === "Accept-Ranges") {
-              return "bytes";
-            } else if (headerName === "Content-Encoding") {
-              return null;
-            } else if (headerName === "Content-Length") {
-              return 8;
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Accept-Ranges": "bytes",
+            "Content-Length": 8,
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -210,16 +183,10 @@ describe("network_utils", function () {
         validateRangeRequestCapabilities({
           disableRange: false,
           isHttp: true,
-          getResponseHeader: headerName => {
-            if (headerName === "Accept-Ranges") {
-              return "bytes";
-            } else if (headerName === "Content-Encoding") {
-              return null;
-            } else if (headerName === "Content-Length") {
-              return 8192;
-            }
-            throw new Error(`Unexpected headerName: ${headerName}`);
-          },
+          responseHeaders: new Headers({
+            "Accept-Ranges": "bytes",
+            "Content-Length": 8192,
+          }),
           rangeChunkSize: 64,
         })
       ).toEqual({
@@ -232,194 +199,173 @@ describe("network_utils", function () {
   describe("extractFilenameFromHeader", function () {
     it("returns null when content disposition header is blank", function () {
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return null;
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            // Empty headers.
+          })
+        )
       ).toBeNull();
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return undefined;
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
-      ).toBeNull();
-
-      expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "",
+          })
+        )
       ).toBeNull();
     });
 
     it("gets the filename from the response header", function () {
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "inline";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "inline",
+          })
+        )
       ).toBeNull();
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "attachment",
+          })
+        )
       ).toBeNull();
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'attachment; filename="filename.pdf"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": 'attachment; filename="filename.pdf"',
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'attachment; filename="filename.pdf and spaces.pdf"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              'attachment; filename="filename.pdf and spaces.pdf"',
+          })
+        )
       ).toEqual("filename.pdf and spaces.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'attachment; filename="tl;dr.pdf"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": 'attachment; filename="tl;dr.pdf"',
+          })
+        )
       ).toEqual("tl;dr.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename=filename.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "attachment; filename=filename.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename=filename.pdf someotherparam";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              "attachment; filename=filename.pdf someotherparam",
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'attachment; filename="%e4%b8%ad%e6%96%87.pdf"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              'attachment; filename="%e4%b8%ad%e6%96%87.pdf"',
+          })
+        )
       ).toEqual("中文.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'attachment; filename="100%.pdf"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": 'attachment; filename="100%.pdf"',
+          })
+        )
       ).toEqual("100%.pdf");
     });
 
     it("gets the filename from the response header (RFC 6266)", function () {
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename*=filename.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "attachment; filename*=filename.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename*=''filename.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "attachment; filename*=''filename.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename*=utf-8''filename.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": "attachment; filename*=utf-8''filename.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename=no.pdf; filename*=utf-8''filename.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              "attachment; filename=no.pdf; filename*=utf-8''filename.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
 
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename*=utf-8''filename.pdf; filename=no.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              "attachment; filename*=utf-8''filename.pdf; filename=no.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
     });
 
     it("gets the filename from the response header (RFC 2231)", function () {
       // Tests continuations (RFC 2231 section 3, via RFC 5987 section 3.1).
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return "attachment; filename*0=filename; filename*1=.pdf";
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              "attachment; filename*0=filename; filename*1=.pdf",
+          })
+        )
       ).toEqual("filename.pdf");
     });
 
     it("only extracts filename with pdf extension", function () {
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'attachment; filename="filename.png"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition": 'attachment; filename="filename.png"',
+          })
+        )
       ).toBeNull();
     });
 
     it("extension validation is case insensitive", function () {
       expect(
-        extractFilenameFromHeader(headerName => {
-          if (headerName === "Content-Disposition") {
-            return 'form-data; name="fieldName"; filename="file.PdF"';
-          }
-          throw new Error(`Unexpected headerName: ${headerName}`);
-        })
+        extractFilenameFromHeader(
+          new Headers({
+            "Content-Disposition":
+              'form-data; name="fieldName"; filename="file.PdF"',
+          })
+        )
       ).toEqual("file.PdF");
     });
   });