Padded attachments, attachments v2

* Handle incoming padded attachments
* Attachments v2 - multipart form POST, and direct CDN GET access
* Pad outgoing attachments before encryption (disabled for now)

js/modules/web_api.js

@@ -5,7 +5,7 @@ const { Agent } = require('https');
 
 const is = require('@sindresorhus/is');
 
-/* global Buffer, setTimeout, log, _ */
+/* global Buffer, setTimeout, log, _, getGuid */
 
 /* eslint-disable more/no-then, no-bitwise, no-nested-ternary */
 
@@ -388,7 +388,7 @@ const URL_CALLS = {
   accounts: 'v1/accounts',
   updateDeviceName: 'v1/accounts/name',
   removeSignalingKey: 'v1/accounts/signaling_key',
-  attachment: 'v1/attachments',
+  attachmentId: 'v2/attachments/form/upload',
   deliveryCert: 'v1/certificate/delivery',
   supportUnauthenticatedDelivery: 'v1/devices/unauthenticated_delivery',
   devices: 'v1/devices',
@@ -834,41 +834,88 @@ function initialize({
       });
     }
 
-    function getAttachment(id) {
-      return _ajax({
-        call: 'attachment',
-        httpType: 'GET',
-        urlParameters: `/${id}`,
-        responseType: 'json',
-        validateResponse: { location: 'string' },
-      }).then(response =>
-        // Using _outerAJAX, since it's not hardcoded to the Signal Server
-        _outerAjax(response.location, {
-          contentType: 'application/octet-stream',
-          proxyUrl,
-          responseType: 'arraybuffer',
-          timeout: 0,
-          type: 'GET',
-        })
-      );
+    async function getAttachment(id) {
+      // This is going to the CDN, not the service, so we use _outerAjax
+      return _outerAjax(`${cdnUrl}/attachments/${id}`, {
+        certificateAuthority,
+        proxyUrl,
+        responseType: 'arraybuffer',
+        timeout: 0,
+        type: 'GET',
+      });
     }
 
-    function putAttachment(encryptedBin) {
-      return _ajax({
-        call: 'attachment',
+    async function putAttachment(encryptedBin) {
+      const response = await _ajax({
+        call: 'attachmentId',
         httpType: 'GET',
         responseType: 'json',
-      }).then(response =>
-        // Using _outerAJAX, since it's not hardcoded to the Signal Server
-        _outerAjax(response.location, {
-          contentType: 'application/octet-stream',
-          data: encryptedBin,
-          processData: false,
-          proxyUrl,
-          timeout: 0,
-          type: 'PUT',
-        }).then(() => response.idString)
+      });
+
+      const {
+        key,
+        credential,
+        acl,
+        algorithm,
+        date,
+        policy,
+        signature,
+        attachmentIdString,
+      } = response;
+
+      // Note: when using the boundary string in the POST body, it needs to be prefixed by
+      //   an extra --, and the final boundary string at the end gets a -- prefix and a --
+      //   suffix.
+      const boundaryString = `----------------${getGuid().replace(/-/g, '')}`;
+      const CRLF = '\r\n';
+      const getSection = (name, value) =>
+        [
+          `--${boundaryString}`,
+          `Content-Disposition: form-data; name="${name}"${CRLF}`,
+          value,
+        ].join(CRLF);
+
+      const start = [
+        getSection('key', key),
+        getSection('x-amz-credential', credential),
+        getSection('acl', acl),
+        getSection('x-amz-algorithm', algorithm),
+        getSection('x-amz-date', date),
+        getSection('policy', policy),
+        getSection('x-amz-signature', signature),
+        getSection('Content-Type', 'application/octet-stream'),
+        `--${boundaryString}`,
+        'Content-Disposition: form-data; name="file"',
+        `Content-Type: application/octet-stream${CRLF}${CRLF}`,
+      ].join(CRLF);
+      const end = `${CRLF}--${boundaryString}--${CRLF}`;
+
+      const startBuffer = Buffer.from(start, 'utf8');
+      const attachmentBuffer = Buffer.from(encryptedBin);
+      const endBuffer = Buffer.from(end, 'utf8');
+
+      const contentLength =
+        startBuffer.length + attachmentBuffer.length + endBuffer.length;
+      const data = Buffer.concat(
+        [startBuffer, attachmentBuffer, endBuffer],
+        contentLength
       );
+
+      // This is going to the CDN, not the service, so we use _outerAjax
+      await _outerAjax(`${cdnUrl}/attachments/`, {
+        certificateAuthority,
+        contentType: `multipart/form-data; boundary=${boundaryString}`,
+        data,
+        proxyUrl,
+        timeout: 0,
+        type: 'POST',
+        headers: {
+          'Content-Length': contentLength,
+        },
+        processData: false,
+      });
+
+      return attachmentIdString;
     }
 
     // eslint-disable-next-line no-shadow