Merge pull request #117 from alphagov/add-overview-of-s3-migration

Add an overview of the migration of assets to S3

README.md

@@ -38,6 +38,8 @@ bundle exec rake jobs:work
 
 ### Assets on S3
 
+See the ["Migrating Asset Manager assets to S3" document](docs/migrating-assets-to-s3.md) for an overview of this project.
+
 This functionality is *very* experimental and should not be switched on in production until performance tests have been carried out to ensure there has been no degradation in performance.
 
 As long as the S3 bucket is configured, all assets are uploaded to the S3 bucket via a separate `Delayed::Job` triggered if virus scanning succeeds. Assets are still saved to the NFS mount as per the original behaviour.

docs/migrating-assets-to-s3.md

@@ -0,0 +1,43 @@
+# Migrating Asset Manager assets to S3
+
+Our goal is to host GOV.UK assets on S3 instead of NFS.
+
+The aim of this document is to provide a high level overview of our progress.
+
+
+## Current status
+
+We've modified Asset Manager to upload assets to S3 in addition to storing them on NFS.
+
+We've tested the performance of proxying requests from Asset Manager to S3 but it's not good enough.
+
+We now want to try redirecting requests from Asset Manager to S3. We have code in Asset Manager to support this but we need objects within our assets bucket to be publicly readable in order for us to test it.
+
+
+## Plan
+
+| Task                                | Integration | Staging | Production |
+| ----------------------------------- | ----------- | ------- | ---------- |
+| Create IAM User                     | Y           | Y       | Y          |
+| Create S3 Bucket                    | Y           | Y       | Y          |
+| Upload assets to S3                 | Y           | Y       | Y          |
+| Optionally proxy to assets on S3    | Y           | Y       | Y          |
+| Public-read on S3 bucket            |             |         |            |
+| Optionally redirect to assets on S3 |             |         |            |
+| S3 access logging                   |             |         |            |
+| S3 CNAME                            |             |         |            |
+| S3 CDN                              | NA          |         |            |
+| Migrate existing assets             |             |         |            |
+| Redirect to assets on S3            |             |         |            |
+| Remove NFS                          |             |         |            |
+
+
+## History
+
+### Mon 7 Aug
+
+* Assets can be proxied from S3 in all environments.
+
+### Wed 2 Aug
+
+* Assets are being uploaded to S3 (as well as being stored on NFS) in all environments.