feat(mime-db): minor updates and version bump (DefinitelyTyped#44029)

- enumerate mime type source as per used sources, which are closed list
- extend tests
- version bump

https://www.npmjs.com/package/mime-db

Thanks!

types/mime-db/index.d.ts

@@ -1,17 +1,20 @@
-// Type definitions for mime-db 1.27
+// Type definitions for mime-db 1.43
 // Project: https://github.com/jshttp/mime-db
 // Definitions by: AJP <https://github.com/AJamesPhillips>
 //                 Linus Unnebäck <https://github.com/LinusU>
+//                 Piotr Błażejewicz <https://github.com/peterblazejewicz>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
-// TypeScript Version: 2.2
 
 declare namespace database {
     /**
      * @see {@link https://github.com/jshttp/mime-db#data-structure}
      */
     interface MimeEntry {
-        /** Where the mime type is defined. If not set, it's probably a custom media type. */
-        readonly source?: string;
+        /**
+         * Where the mime type is defined.
+         * If not set, it's probably a custom media type.
+         */
+        readonly source?: MimeSource;
         /** Known extensions associated with this mime type. */
         readonly extensions?: ReadonlyArray<string>;
         /** Whether a file of this type can be gzipped. */
@@ -26,6 +29,14 @@ declare namespace database {
     interface MimeDatabase {
         readonly [type: string]: MimeEntry;
     }
+
+    /**
+     * Sources:
+     * http://www.iana.org/assignments/media-types/media-types.xhtml
+     * http://svn.apache.org/repos/asf/httpd/httpd/trunk/docs/conf/mime.types
+     * http://hg.nginx.org/nginx/raw-file/default/conf/mime.types
+     */
+    type MimeSource = 'iana' | 'apache' | 'nginx';
 }
 
 declare const database: database.MimeDatabase;

types/mime-db/mime-db-tests.ts

@@ -11,3 +11,12 @@ database['text/markdown'].extensions;
 
 // $ExpectType string
 database['text/markdown'].extensions![0];
+
+// $ExpectType "iana" | "apache" | "nginx" | undefined
+database['text/markdown'].source;
+
+// $ExpectType string | undefined
+database['text/markdown'].charset;
+
+// $ExpectType boolean | undefined
+database['text/markdown'].compressible;