Add Companion section

Author: Murderlon

blog/2024-07-3-uppy-4.0.md

@@ -10,7 +10,7 @@ published: false
 toc_max_heading_level: 2
 ---
 
-Hi ha ho, this is some goofy introduction.
+Hi ha, this is some goofy introduction.
 
 ## TypeScript rewrite
 
@@ -87,7 +87,7 @@ you are spending 400ms on overhead and only a few milliseconds on uploading.
 This really adds up if you upload a lot of small files.
 
 AWS, and generally the internet from what we found, tend to agree that **you
-don't want to use multipart uploads for files under 100MB**. But this sometimes
+don’t want to use multipart uploads for files under 100MB**. But this sometimes
 puts users of our libraries in an awkward position, as their end users may not
 only upload very large files, or only small files. In this case a portion of
 their users get a subpar experience.
@@ -104,7 +104,7 @@ You can pass a `boolean` or a function to determine it per file.
 ## React hooks
 
 People working with React are more likely to create their own user interface on
-top of Uppy than those working with "vanilla" setups. Working with our pre-build
+top of Uppy than those working with “vanilla” setups. Working with our pre-build
 UI components is a plug-and-play experience, but building on top of Uppy’s state
 with React primitives has been tedious.
 
@@ -196,10 +196,6 @@ select files.
 
 We now made a handful of quality of life improvements for users.
 
-|                Before                 | After |
-| :-----------------------------------: | :---: |
-| ![yeah](/img/blog/3.13-3.21/crop.mov) | yeah  |
-
 <!-- TODO: video of the improvements-->
 
 - **Folder caching**. When naviging in and out of folders, you now no longer
@@ -229,6 +225,34 @@ results beyond the first page API limit of providers.
 
 ## Companion
 
+### Streaming uploads by default
+
+Streaming uploads are now the default in in Companion. This comes with greatly
+improved upload speeds and allows uploading up to hundreds of gigabytes without
+needing a large server storage. We found that this improves speeds by about 37%
+for a Google Drive upload of a 1 GB file
+([source](https://github.com/transloadit/uppy/pull/4046#issuecomment-1235697937)).
+This feature was also available before but we wanted to have more real world
+usage before setting it as the default.
+
+With streaming upload disabled, the whole file will be downloaded first. The
+upload will then start when the download has completely finished.
+
+When streaming upload is enabled, Companion will start downloading the file from
+the provider (such as Google Drive), while at the same time starting the upload
+to the destination (such as Tus), and sending every chunk of data consecutively.
+
+For more information, see the [Companion docs](/docs/companion/).
+
+### New required option `corsOrigins`
+
+As a security measure, we now require the
+[`corsOrigins`](/docs/companion/#corsorigins) option to be set.
+
+It serves two purposes, it sets the `Access-Control-Allow-Origin` header and it
+sets the origin for `window.postMessage()`, which is needed to communicate the
+OAuth token from the new tab you used to log-in to a provider back to Companion.
+
 ## And more
 
 The 4.0 release contained over 170 contributions, many too small to mention, but