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authorGitLab Bot <gitlab-bot@gitlab.com>2022-03-18 23:02:30 +0300
committerGitLab Bot <gitlab-bot@gitlab.com>2022-03-18 23:02:30 +0300
commit41fe97390ceddf945f3d967b8fdb3de4c66b7dea (patch)
tree9c8d89a8624828992f06d892cd2f43818ff5dcc8 /doc/development/uploads
parent0804d2dc31052fb45a1efecedc8e06ce9bc32862 (diff)
Add latest changes from gitlab-org/gitlab@14-9-stable-eev14.9.0-rc42
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-rw-r--r--doc/development/uploads/implementation.md190
-rw-r--r--doc/development/uploads/index.md14
-rw-r--r--doc/development/uploads/working_with_uploads.md163
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diff --git a/doc/development/uploads/background.md b/doc/development/uploads/background.md
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+---
+stage: none
+group: unassigned
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Uploads guide: Why GitLab uses custom upload logic
+
+This page is for developers trying to better understand the history behind GitLab uploads and the
+technical challenges associated with uploads.
+
+## Problem description
+
+GitLab and [GitLab Workhorse](https://gitlab.com/gitlab-org/gitlab-workhorse) use special rules for handling file uploads,
+because in an ordinary Rails application file uploads can become expensive as files grow in size.
+Rails often sacrifices performance to provide a better developer experience, including how it handles
+`multipart/form-post` uploads. In any Rack server, Rails applications included, when such a request arrives at the application server,
+several things happen:
+
+1. A [Rack middleware](https://github.com/rack/rack/blob/main/lib/rack/multipart.rb) intercepts the request and parses the request body.
+1. The middleware writes each file in the multipart request to a temporary directory on disk.
+1. A `params` hash is constructed with entries pointing to the respective files on disk.
+1. A Rails controller acts on the file contents.
+
+While this is convenient for developers, it is costly for the Ruby server process to buffer large files on disk.
+Because of Ruby's [global interpreter lock](https://en.wikipedia.org/wiki/Global_interpreter_lock),
+only a single thread of execution of a given Ruby process can be on CPU. This means the amount of CPU
+time spent doing this is not available to other worker threads serving user requests.
+Buffering files to disk also means spending more time in I/O routines and mode switches, which are expensive operations.
+
+The following diagram shows how GitLab handled such a request prior to putting optimizations in place.
+
+```mermaid
+graph TB
+ subgraph "load balancers"
+ LB(Proxy)
+ end
+
+ subgraph "Shared storage"
+ nfs(NFS)
+ end
+
+ subgraph "redis cluster"
+ r(persisted redis)
+ end
+ LB-- 1 -->Workhorse
+
+ subgraph "web or API fleet"
+ Workhorse-- 2 -->rails
+ end
+ rails-- "3 (write files)" -->nfs
+ rails-- "4 (schedule a job)" -->r
+
+ subgraph sidekiq
+ s(sidekiq)
+ end
+ s-- "5 (fetch a job)" -->r
+ s-- "6 (read files)" -->nfs
+```
+
+We went through two major iterations of our uploads architecture to improve on these problems:
+
+1. [Moving disk buffering to Workhorse.](#moving-disk-buffering-to-workhorse)
+1. [Uploading to Object Storage from Workhorse.](#moving-to-object-storage-and-direct-uploads)
+
+### Moving disk buffering to Workhorse
+
+To address the performance issues resulting from buffering files in Ruby, we moved this logic to Workhorse instead,
+our reverse proxy fronting the GitLab Rails application.
+Workhorse is written in Go, and is much better at dealing with stream processing and I/O than Rails.
+
+There are two parts to this implementation:
+
+1. In Workhorse, a request handler detects `multipart/form-data` content in an incoming user request.
+ If such a request is detected, Workhorse hijacks the request body before forwarding it to Rails.
+ Workhorse writes all files to disk, rewrites the multipart form fields to point to the new locations, signs the
+ request, then forwards it to Rails.
+1. In Rails, a [custom multipart Rack middleware](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/middleware/multipart.rb)
+ identifies any signed multipart requests coming from Workhorse and prepares the `params` hash Rails
+ would expect, now pointing to the files cached by Workhorse. This makes it a drop-in replacement for `Rack::Multipart`.
+
+The diagram below shows how GitLab handles such a request today:
+
+```mermaid
+graph TB
+ subgraph "load balancers"
+ LB(HA Proxy)
+ end
+
+ subgraph "Shared storage"
+ nfs(NFS)
+ end
+
+ subgraph "redis cluster"
+ r(persisted redis)
+ end
+ LB-- 1 -->Workhorse
+
+ subgraph "web or API fleet"
+ Workhorse-- "3 (without files)" -->rails
+ end
+ Workhorse -- "2 (write files)" -->nfs
+ rails-- "4 (schedule a job)" -->r
+
+ subgraph sidekiq
+ s(sidekiq)
+ end
+ s-- "5 (fetch a job)" -->r
+ s-- "6 (read files)" -->nfs
+```
+
+While this "one-size-fits-all" solution greatly improves performance for multipart uploads without compromising
+developer ergonomics, it severely limits GitLab [availability](#availability-challenges)
+and [scalability](#scalability-challenges).
+
+#### Availability challenges
+
+Moving file buffering to Workhorse addresses the immediate performance problems stemming from Ruby not being good at
+handling large file uploads. However, a remaining issue of this solution is its reliance on attached storage,
+whether via ordinary hard drives or network attached storage like NFS.
+NFS is a [single point of failure](https://en.wikipedia.org/wiki/Single_point_of_failure), and is unsuitable for
+deploying GitLab in highly available, cloud native environments.
+
+#### Scalability challenges
+
+NFS is not a part of cloud native installations, such as those running in Kubernetes.
+In Kubernetes, machine boundaries translate to pods, and without network-attached storage, disk-buffered uploads
+must be written directly to the pod's file system.
+
+Using disk buffering presents us with a scalability challenge here. If Workhorse can only
+write files to a pod's private file system, then these files are inaccessible outside of this particular pod.
+With disk buffering, a Rails controller will accept a file upload and enqueue it for upload in a Sidekiq
+background job. Therefore, Sidekiq requires access to these files.
+However, in a cloud native environment all Sidekiq instances run on separate pods, so they are
+not able to access files buffered to disk on a web server pod.
+
+Therefore, all features that involve Sidekiq uploading disk-buffered files severely limit the scalability of GitLab.
+
+## Moving to object storage and direct uploads
+
+To address these availability and scalability problems,
+instead of buffering files to disk, we have added support for uploading files directly
+from Workhorse to a given destination. While it remains possible to upload to local or network-attached storage
+this way, you should use a highly available
+[object store](https://en.wikipedia.org/wiki/Object_storage),
+such as AWS S3, Google GCS, or Azure, for scalability reasons.
+
+With direct uploads, Workhorse does not buffer files to disk. Instead, it first authorizes the request with
+the Rails application to find out where to upload it, then streams the file directly to its ultimate destination.
+
+To learn more about how disk buffering and direct uploads are implemented, see:
+
+- [How uploads work technically](implementation.md)
+- [Adding new uploads](working_with_uploads.md)
diff --git a/doc/development/uploads/implementation.md b/doc/development/uploads/implementation.md
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+---
+stage: none
+group: unassigned
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Uploads guide: How uploads work technically
+
+This page is for developers trying to better understand what kinds of uploads exist in GitLab and how they are implemented.
+
+## Kinds of uploads and how to choose between them
+
+We can identify three major use-cases for an upload:
+
+1. **storage:** if we are uploading for storing a file (like artifacts, packages, or discussion attachments). In this case [direct upload](#direct-upload) is the proper level as it's the less resource-intensive operation. Additional information can be found on [File Storage in GitLab](../file_storage.md).
+1. **in-controller/synchronous processing:** if we allow processing **small files** synchronously, using [disk buffered upload](#disk-buffered-upload) may speed up development.
+1. **Sidekiq/asynchronous processing:** Asynchronous processing must implement [direct upload](#direct-upload), the reason being that it's the only way to support Cloud Native deployments without a shared NFS.
+
+Selecting the proper acceleration is a tradeoff between speed of development and operational costs.
+
+For more details about currently broken feature see [epic &1802](https://gitlab.com/groups/gitlab-org/-/epics/1802).
+
+### Handling repository uploads
+
+Some features involves Git repository uploads without using a regular Git client.
+Some examples are uploading a repository file from the web interface and [design management](../../user/project/issues/design_management.md).
+
+Those uploads requires the rails controller to act as a Git client in lieu of the user.
+Those operation falls into _in-controller/synchronous processing_ category, but we have no warranties on the file size.
+
+In case of a LFS upload, the file pointer is committed synchronously, but file upload to object storage is performed asynchronously with Sidekiq.
+
+## Upload encodings
+
+By upload encoding we mean how the file is included within the incoming request.
+
+We have three kinds of file encoding in our uploads:
+
+1. <i class="fa fa-check-circle"></i> **multipart**: `multipart/form-data` is the most common, a file is encoded as a part of a multipart encoded request.
+1. <i class="fa fa-check-circle"></i> **body**: some APIs uploads files as the whole request body.
+1. <i class="fa fa-times-circle"></i> **JSON**: some JSON APIs upload files as base64-encoded strings. This requires a change to GitLab Workhorse,
+ which is tracked [in this issue](https://gitlab.com/gitlab-org/gitlab/-/issues/325068).
+
+## Uploading technologies
+
+By uploading technologies we mean how all the involved services interact with each other.
+
+GitLab supports 3 kinds of uploading technologies, here follows a brief description with a sequence diagram for each one. Diagrams are not meant to be exhaustive.
+
+### Rack Multipart upload
+
+This is the default kind of upload, and it's the most expensive in terms of resources.
+
+In this case, Workhorse is unaware of files being uploaded and acts as a regular proxy.
+
+When a multipart request reaches the rails application, `Rack::Multipart` leaves behind temporary files in `/tmp` and uses valuable Ruby process time to copy files around.
+
+```mermaid
+sequenceDiagram
+ participant c as Client
+ participant w as Workhorse
+ participant r as Rails
+
+ activate c
+ c ->>+w: POST /some/url/upload
+ w->>+r: POST /some/url/upload
+
+ r->>r: save the incoming file on /tmp
+ r->>r: read the file for processing
+
+ r-->>-c: request result
+ deactivate c
+ deactivate w
+```
+
+### Disk buffered upload
+
+This kind of upload avoids wasting resources caused by handling upload writes to `/tmp` in rails.
+
+This optimization is not active by default on REST API requests.
+
+When enabled, Workhorse looks for files in multipart MIME requests, uploading
+any it finds to a temporary file on shared storage. The MIME data in the request
+is replaced with the path to the corresponding file before it is forwarded to
+Rails.
+
+To prevent abuse of this feature, Workhorse signs the modified request with a
+special header, stating which entries it modified. Rails ignores any
+unsigned path entries.
+
+```mermaid
+sequenceDiagram
+ participant c as Client
+ participant w as Workhorse
+ participant r as Rails
+ participant s as NFS
+
+ activate c
+ c ->>+w: POST /some/url/upload
+
+ w->>+s: save the incoming file on a temporary location
+ s-->>-w: request result
+
+ w->>+r: POST /some/url/upload
+ Note over w,r: file was replaced with its location<br>and other metadata
+
+ opt requires async processing
+ r->>+redis: schedule a job
+ redis-->>-r: job is scheduled
+ end
+
+ r-->>-c: request result
+ deactivate c
+ w->>-w: cleanup
+
+ opt requires async processing
+ activate sidekiq
+ sidekiq->>+redis: fetch a job
+ redis-->>-sidekiq: job
+
+ sidekiq->>+s: read file
+ s-->>-sidekiq: file
+
+ sidekiq->>sidekiq: process file
+
+ deactivate sidekiq
+ end
+```
+
+### Direct upload
+
+This is the more advanced acceleration technique we have in place.
+
+Workhorse asks Rails for temporary pre-signed object storage URLs and directly uploads to object storage.
+
+In this setup, an extra Rails route must be implemented in order to handle authorization. Examples of this can be found in:
+
+- [`Projects::LfsStorageController`](https://gitlab.com/gitlab-org/gitlab/-/blob/cc723071ad337573e0360a879cbf99bc4fb7adb9/app/controllers/projects/lfs_storage_controller.rb)
+ and [its routes](https://gitlab.com/gitlab-org/gitlab/-/blob/cc723071ad337573e0360a879cbf99bc4fb7adb9/config/routes/git_http.rb#L31-32).
+- [API endpoints for uploading packages](../packages.md#file-uploads).
+
+Direct upload falls back to _disk buffered upload_ when `direct_upload` is disabled inside the [object storage setting](../../administration/uploads.md#object-storage-settings).
+The answer to the `/authorize` call contains only a file system path.
+
+```mermaid
+sequenceDiagram
+ participant c as Client
+ participant w as Workhorse
+ participant r as Rails
+ participant os as Object Storage
+
+ activate c
+ c ->>+w: POST /some/url/upload
+
+ w ->>+r: POST /some/url/upload/authorize
+ Note over w,r: this request has an empty body
+ r-->>-w: presigned OS URL
+
+ w->>+os: PUT file
+ Note over w,os: file is stored on a temporary location. Rails select the destination
+ os-->>-w: request result
+
+ w->>+r: POST /some/url/upload
+ Note over w,r: file was replaced with its location<br>and other metadata
+
+ r->>+os: move object to final destination
+ os-->>-r: request result
+
+ opt requires async processing
+ r->>+redis: schedule a job
+ redis-->>-r: job is scheduled
+ end
+
+ r-->>-c: request result
+ deactivate c
+ w->>-w: cleanup
+
+ opt requires async processing
+ activate sidekiq
+ sidekiq->>+redis: fetch a job
+ redis-->>-sidekiq: job
+
+ sidekiq->>+os: get object
+ os-->>-sidekiq: file
+
+ sidekiq->>sidekiq: process file
+
+ deactivate sidekiq
+ end
+```
diff --git a/doc/development/uploads/index.md b/doc/development/uploads/index.md
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+---
+stage: none
+group: unassigned
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Uploads development guide
+
+Uploads are an integral part of many GitLab features. To understand how GitLab handles uploads, refer to
+the following pages:
+
+- [Why GitLab uses custom upload logic.](background.md)
+- [How uploads work technically.](implementation.md)
+- [How to add new uploads.](working_with_uploads.md)
diff --git a/doc/development/uploads/working_with_uploads.md b/doc/development/uploads/working_with_uploads.md
new file mode 100644
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--- /dev/null
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+---
+stage: none
+group: unassigned
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Uploads guide: Adding new uploads
+
+In this section, we describe how to add a new upload route [accelerated](implementation.md#uploading-technologies) by Workhorse for [body and multipart](implementation.md#upload-encodings) encoded uploads.
+
+Upload routes belong to one of these categories:
+
+1. Rails controllers: uploads handled by Rails controllers.
+1. Grape API: uploads handled by a Grape API endpoint.
+1. GraphQL API: uploads handled by a GraphQL resolve function.
+
+WARNING:
+GraphQL uploads do not support [direct upload](implementation.md#direct-upload) yet. Depending on the use case, the feature may not work on installations without NFS (like GitLab.com or Kubernetes installations). Uploading to object storage inside the GraphQL resolve function may result in timeout errors. For more details please follow [issue #280819](https://gitlab.com/gitlab-org/gitlab/-/issues/280819).
+
+## Update Workhorse for the new route
+
+For both the Rails controller and Grape API uploads, Workhorse has to be updated in order to get the
+support for the new upload route.
+
+1. Open a new issue in the [Workhorse tracker](https://gitlab.com/gitlab-org/gitlab-workhorse/-/issues/new) describing precisely the new upload route:
+ - The route's URL.
+ - The [upload encoding](implementation.md#upload-encodings).
+ - If possible, provide a dump of the upload request.
+1. Implement and get the MR merged for this issue above.
+1. Ask the Maintainers of [Workhorse](https://gitlab.com/gitlab-org/gitlab-workhorse) to create a new release. You can do that in the MR
+ directly during the maintainer review or ask for it in the `#workhorse` Slack channel.
+1. Bump the [Workhorse version file](https://gitlab.com/gitlab-org/gitlab/-/blob/master/GITLAB_WORKHORSE_VERSION)
+ to the version you have from the previous points, or bump it in the same merge request that contains
+ the Rails changes (see [Implementing the new route with a Rails controller](#implementing-the-new-route-with-a-rails-controller) or [Implementing the new route with a Grape API endpoint](#implementing-the-new-route-with-a-grape-api-endpoint) below).
+
+## Implementing the new route with a Rails controller
+
+For a Rails controller upload, we usually have a [multipart](implementation.md#upload-encodings) upload and there are a
+few things to do:
+
+1. The upload is available under the parameter name you're using. For example, it could be an `artifact`
+ or a nested parameter such as `user[avatar]`. Let's say that we have the upload under the
+ `file` parameter, reading `params[:file]` should get you an [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb) instance.
+1. Generally speaking, it's a good idea to check if the instance is from the [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb) class. For example, see how we checked
+[that the parameter is indeed an `UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/commit/ea30fe8a71bf16ba07f1050ab4820607b5658719#51c0cc7a17b7f12c32bc41cfab3649ff2739b0eb_79_77).
+
+WARNING:
+**Do not** call `UploadedFile#from_params` directly! Do not build an [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb)
+instance using `UploadedFile#from_params`! This method can be unsafe to use depending on the `params`
+passed. Instead, use the [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb)
+instance that [`multipart.rb`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/middleware/multipart.rb)
+builds automatically for you.
+
+## Implementing the new route with a Grape API endpoint
+
+For a Grape API upload, we can have [body or a multipart](implementation.md#upload-encodings) upload. Things are slightly more complicated: two endpoints are needed. One for the
+Workhorse pre-upload authorization and one for accepting the upload metadata from Workhorse:
+
+1. Implement an endpoint with the URL + `/authorize` suffix that will:
+ - Check that the request is coming from Workhorse with the `require_gitlab_workhorse!` from the [API helpers](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/api/helpers.rb).
+ - Check user permissions.
+ - Set the status to `200` with `status 200`.
+ - Set the content type with `content_type Gitlab::Workhorse::INTERNAL_API_CONTENT_TYPE`.
+ - Use your dedicated `Uploader` class (let's say that it's `FileUploader`) to build the response with `FileUploader.workhorse_authorize(params)`.
+1. Implement the endpoint for the upload request that will:
+ - Require all the `UploadedFile` objects as parameters.
+ - For example, if we expect a single parameter `file` to be an [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb) instance,
+use `requires :file, type: ::API::Validations::Types::WorkhorseFile`.
+ - Body upload requests have their upload available under the parameter `file`.
+ - Check that the request is coming from Workhorse with the `require_gitlab_workhorse!` from the
+[API helpers](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/api/helpers.rb).
+ - Check the user permissions.
+ - The remaining code of the processing. This is where the code must be reading the parameter (for
+our example, it would be `params[:file]`).
+
+WARNING:
+**Do not** call `UploadedFile#from_params` directly! Do not build an [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb)
+object using `UploadedFile#from_params`! This method can be unsafe to use depending on the `params`
+passed. Instead, use the [`UploadedFile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/uploaded_file.rb)
+object that [`multipart.rb`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/middleware/multipart.rb)
+builds automatically for you.
+
+## Document Object Storage buckets and CarrierWave integration
+
+When using Object Storage, GitLab expects each kind of upload to maintain its own bucket in the respective
+Object Storage destination. Moreover, the integration with CarrierWave is not used all the time.
+The [Object Storage Working Group](https://about.gitlab.com/company/team/structure/working-groups/object-storage/)
+is investigating an approach that unifies Object Storage buckets into a single one and removes CarrierWave
+so as to simplify implementation and administration of uploads.
+
+Therefore, document new uploads here by slotting them into the following tables:
+
+- [Feature bucket details](#feature-bucket-details)
+- [CarrierWave integration](#carrierwave-integration)
+
+### Feature bucket details
+
+| Feature | Upload technology | Uploader | Bucket structure |
+|------------------------------------------|-------------------|-----------------------|-----------------------------------------------------------------------------------------------------------|
+| Job artifacts | `direct upload` | `workhorse` | `/artifacts/<proj_id_hash>/<date>/<job_id>/<artifact_id>` |
+| Pipeline artifacts | `carrierwave` | `sidekiq` | `/artifacts/<proj_id_hash>/pipelines/<pipeline_id>/artifacts/<artifact_id>` |
+| Live job traces | `fog` | `sidekiq` | `/artifacts/tmp/builds/<job_id>/chunks/<chunk_index>.log` |
+| Job traces archive | `carrierwave` | `sidekiq` | `/artifacts/<proj_id_hash>/<date>/<job_id>/<artifact_id>/job.log` |
+| Autoscale runner caching | N/A | `gitlab-runner` | `/gitlab-com-[platform-]runners-cache/???` |
+| Backups | N/A | `s3cmd`, `awscli`, or `gcs` | `/gitlab-backups/???` |
+| Git LFS | `direct upload` | `workhorse` | `/lsf-objects/<lfs_obj_oid[0:2]>/<lfs_obj_oid[2:2]>` |
+| Design management files | `disk buffering` | `rails controller` | `/lsf-objects/<lfs_obj_oid[0:2]>/<lfs_obj_oid[2:2]>` |
+| Design management thumbnails | `carrierwave` | `sidekiq` | `/uploads/design_management/action/image_v432x230/<model_id>` |
+| Generic file uploads | `direct upload` | `workhorse` | `/uploads/@hashed/[0:2]/[2:4]/<hash1>/<hash2>/file` |
+| Generic file uploads - personal snippets | `direct upload` | `workhorse` | `/uploads/personal_snippet/<snippet_id>/<filename>` |
+| Global appearance settings | `disk buffering` | `rails controller` | `/uploads/appearance/...` |
+| Topics | `disk buffering` | `rails controller` | `/uploads/projects/topic/...` |
+| Avatar images | `direct upload` | `workhorse` | `/uploads/[user,group,project]/avatar/<model_id>` |
+| Import/export | `direct upload` | `workhorse` | `/uploads/import_export_upload/???` |
+| GitLab Migration | `carrierwave` | `sidekiq` | `/uploads/bulk_imports/???` |
+| MR diffs | `carrierwave` | `sidekiq` | `/external-diffs/merge_request_diffs/mr-<mr_id>/diff-<diff_id>` |
+| Package manager archives | `direct upload` | `sidekiq` | `/packages/<proj_id_hash>/packages/<pkg_segment>/files/<pkg_file_id>` |
+| Package manager archives | `direct upload` | `sidekiq` | `/packages/<container_id_hash>/debian_*_component_file/<component_file_id>` |
+| Package manager archives | `direct upload` | `sidekiq` | `/packages/<container_id_hash>/debian_*_distribution/<distribution_file_id>` |
+| Container image cache (?) | `direct upload` | `workhorse` | `/dependency-proxy/<group_id_hash>/dependency_proxy/<group_id>/files/<proxy_id>/<blob_id or manifest_id>` |
+| Terraform state files | `carrierwave` | `rails controller` | `/terraform/<proj_id_hash>/<terraform_state_id>` |
+| Pages content archives | `carrierwave` | `sidekiq` | `/gitlab-gprd-pages/<proj_id_hash>/pages_deployments/<deployment_id>/` |
+| Secure Files | `carrierwave` | `sidekiq` | `/ci-secure-files/<proj_id_hash>/secure_files/<secure_file_id>/` |
+
+### CarrierWave integration
+
+| File | Carrierwave usage | Categorized |
+|---------------------------------------------------------|----------------------------------------------------------------------------------|---------------------|
+| `app/models/project.rb` | `include Avatarable` | :white_check_mark: |
+| `app/models/projects/topic.rb` | `include Avatarable` | :white_check_mark: |
+| `app/models/group.rb` | `include Avatarable` | :white_check_mark: |
+| `app/models/user.rb` | `include Avatarable` | :white_check_mark: |
+| `app/models/terraform/state_version.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/ci/job_artifact.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/ci/pipeline_artifact.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/pages_deployment.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/lfs_object.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/dependency_proxy/blob.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/dependency_proxy/manifest.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/packages/composer/cache_file.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/packages/package_file.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `app/models/concerns/packages/debian/component_file.rb` | `include FileStoreMounter` | :white_check_mark: |
+| `ee/app/models/issuable_metric_image.rb` | `include FileStoreMounter` | |
+| `ee/app/models/vulnerabilities/remediation.rb` | `include FileStoreMounter` | |
+| `ee/app/models/vulnerabilities/export.rb` | `include FileStoreMounter` | |
+| `app/models/packages/debian/project_distribution.rb` | `include Packages::Debian::Distribution` | :white_check_mark: |
+| `app/models/packages/debian/group_distribution.rb` | `include Packages::Debian::Distribution` | :white_check_mark: |
+| `app/models/packages/debian/project_component_file.rb` | `include Packages::Debian::ComponentFile` | :white_check_mark: |
+| `app/models/packages/debian/group_component_file.rb` | `include Packages::Debian::ComponentFile` | :white_check_mark: |
+| `app/models/merge_request_diff.rb` | `mount_uploader :external_diff, ExternalDiffUploader` | :white_check_mark: |
+| `app/models/note.rb` | `mount_uploader :attachment, AttachmentUploader` | :white_check_mark: |
+| `app/models/appearance.rb` | `mount_uploader :logo, AttachmentUploader` | :white_check_mark: |
+| `app/models/appearance.rb` | `mount_uploader :header_logo, AttachmentUploader` | :white_check_mark: |
+| `app/models/appearance.rb` | `mount_uploader :favicon, FaviconUploader` | :white_check_mark: |
+| `app/models/project.rb` | `mount_uploader :bfg_object_map, AttachmentUploader` | |
+| `app/models/import_export_upload.rb` | `mount_uploader :import_file, ImportExportUploader` | :white_check_mark: |
+| `app/models/import_export_upload.rb` | `mount_uploader :export_file, ImportExportUploader` | :white_check_mark: |
+| `app/models/ci/deleted_object.rb` | `mount_uploader :file, DeletedObjectUploader` | |
+| `app/models/design_management/action.rb` | `mount_uploader :image_v432x230, DesignManagement::DesignV432x230Uploader` | :white_check_mark: |
+| `app/models/concerns/packages/debian/distribution.rb` | `mount_uploader :signed_file, Packages::Debian::DistributionReleaseFileUploader` | :white_check_mark: |
+| `app/models/bulk_imports/export_upload.rb` | `mount_uploader :export_file, ExportUploader` | :white_check_mark: |
+| `ee/app/models/user_permission_export_upload.rb` | `mount_uploader :file, AttachmentUploader` | |
+| `app/models/ci/secure_file.rb` | `include FileStoreMounter` | |