[api-minor] Implement securityHandler in the scripting API (bug 1731578)

Author: janekotovich

src/core/crypto.js

@@ -1689,6 +1689,7 @@ const CipherTransformFactory = (function CipherTransformFactoryClosure() {
       if (!isName(filter, "Standard")) {
         throw new FormatError("unknown encryption method");
       }
+      this.filterName = filter.name;
       this.dict = dict;
       const algorithm = dict.get("V");
       if (

src/core/document.js

@@ -1162,6 +1162,9 @@ class PDFDocument {
       PDFFormatVersion: version,
       Language: this.catalog.lang,
       IsLinearized: !!this.linearization,
+      EncryptFilterName: this.xref.encrypt
+        ? this.xref.encrypt.filterName
+        : null,
       IsAcroFormPresent: this.formInfo.hasAcroForm,
       IsXFAPresent: this.formInfo.hasXfa,
       IsCollectionPresent: !!this.catalog.collection,

src/scripting_api/doc.js

@@ -66,6 +66,7 @@ class Doc extends PDFObject {
     this._numPages = data.numPages || 1;
     this._pageNum = data.pageNum || 0;
     this._producer = data.Producer || "";
+    this._securityHandler = data.EncryptFilterName || null;
     this._subject = data.Subject || "";
     this._title = data.Title || "";
     this._URL = data.URL || "";
@@ -522,7 +523,7 @@ class Doc extends PDFObject {
   }
 
   get securityHandler() {
-    return null;
+    return this._securityHandler;
   }
 
   set securityHandler(_) {

test/unit/api_spec.js

@@ -1166,6 +1166,7 @@ describe("api", function () {
       // The following are PDF.js specific, non-standard, properties.
       expect(info.PDFFormatVersion).toEqual("1.7");
       expect(info.Language).toEqual("en");
+      expect(info.EncryptFilterName).toEqual(null);
       expect(info.IsLinearized).toEqual(false);
       expect(info.IsAcroFormPresent).toEqual(false);
       expect(info.IsXFAPresent).toEqual(false);
@@ -1201,6 +1202,7 @@ describe("api", function () {
       // The following are PDF.js specific, non-standard, properties.
       expect(info.PDFFormatVersion).toEqual("1.4");
       expect(info.Language).toEqual(null);
+      expect(info.EncryptFilterName).toEqual(null);
       expect(info.IsLinearized).toEqual(false);
       expect(info.IsAcroFormPresent).toEqual(false);
       expect(info.IsXFAPresent).toEqual(false);
@@ -1223,6 +1225,7 @@ describe("api", function () {
       // The following are PDF.js specific, non-standard, properties.
       expect(info.PDFFormatVersion).toEqual(null);
       expect(info.Language).toEqual(null);
+      expect(info.EncryptFilterName).toEqual(null);
       expect(info.IsLinearized).toEqual(false);
       expect(info.IsAcroFormPresent).toEqual(false);
       expect(info.IsXFAPresent).toEqual(false);