Add documentation around releases (#26602)

docs/SUMMARY.md

@@ -37,3 +37,4 @@
 -   [Jitsi](jitsi-dev.md)
 -   [Feature flags](feature-flags.md)
 -   [OIDC and delegated authentication](oidc.md)
+-   [Release Process](release.md)

docs/release.md

@@ -0,0 +1,268 @@
+> Tip: Paste this into the browser console to make the checkboxes on this page tickable. (Bear in mind that your ticks will be lost if you reload though.)
+>
+> ```
+> document.querySelectorAll("input[type='checkbox']").forEach(i => {i.disabled = false;})
+> ```
+
+<details><summary><h1>Branches</h1></summary><blockquote>
+
+#### develop
+
+The develop branch holds the very latest and greatest code we have to offer, as such it may be less stable. It corresponds to the develop.element.io CD platform.
+
+#### staging
+
+The staging branch corresponds to the very latest release regardless of whether it is an RC or not. Deployed to staging.element.io manually.
+
+#### master
+
+The master branch is the most stable as it is the very latest non-RC release. Deployed to app.element.io manually.
+
+</blockquote></details>
+
+<details><summary><h1>Versions</h1></summary><blockquote>
+
+The matrix-js-sdk follows semver, the matrix-react-sdk loosely follows semver, most releases for both will bump the minor version number.
+Breaking changes will bump the major version number.
+Element Web & Element Desktop do not follow semver and always have matching version numbers. The patch version number is normally incremented for every release.
+
+</blockquote></details>
+
+<details><summary><h1>Release Types</h1></summary><blockquote>
+
+#### Release candidate
+
+A normal release begins with a Release Candidate on the Tick phase of the release cycle,
+and may contain as many further RCs as are needed before the Tock phase of cycle.
+Each subsequent RC may add additional commits via any of the means of preparation.
+
+A normal release is the most typical run-of-the-mill release,
+with at least one RC (Release Candidate) followed by a FINAL release.
+The typical cadence for these is every 2 weeks we'll do a new initial RC,
+then the following week we'll do that release cycle's FINAL release with sometimes more RCs in between, as needed.
+
+#### Final
+
+A normal release culminates with a Final release on the Tock phase of the cycle.
+This may be merely shipping the very latest RC with an adjusted version number,
+but can also include (hopefully small) additional changes present on `staging` if they are deemed safe to skip an RC.
+
+### Hotfix / Security
+
+This is an accelerated type of release which sits somewhere between RC and Final.
+They tend to contain few patches delta from the previous release but also skip any form of RC
+and in the case of Security the patch lands on GitHub only moments prior.
+For all intents and purposes they are the same as a Final release but with a different purpose.
+
+</blockquote></details>
+
+<details><summary><h1>Release Blockers</h1></summary><blockquote>
+
+You should become release rabbit on the day after the last full release.
+For that week, it's your job to keep an eye on the Releases room and see whether any issues marked `X-Release-Blocker` are opened,
+or were already open. You should chase people to fix them, so that on RC day you can make the release.
+
+If release-blocking issues are still open, you need to delay the release until they are fixed or reclassified.
+
+There are two labels for tracking release blockers.
+
+#### X-Release-Blocker
+
+This label applied to an issue means we cannot ship a release affected by the specific issue.
+This means we cannot cut branches for an RC but security & hotfix releases may still be fine.
+
+#### X-Upcoming-Release-Blocker
+
+This label applied to an issue means that the next (read: not current) release cycle will be affected by the specific issue.
+This label will automagically convert to `X-Release-Blocker` at the conclusion of a full release.
+
+</blockquote></details>
+
+<details><summary><h1>Repositories</h1></summary><blockquote>
+
+This release process revolves around our four main repositories:
+
+-   [Element Desktop](https://github.com/vector-im/element-desktop/)
+-   [Element Web](https://github.com/vector-im/element-web/)
+-   [Matrix React SDK](https://github.com/matrix-org/matrix-react-sdk/)
+-   [Matrix JS SDK](https://github.com/matrix-org/matrix-js-sdk/)
+
+We own other repositories, but they have more ad-hoc releases and are not part of the bi-weekly cycle:
+
+-   https://github.com/matrix-org/matrix-web-i18n/
+-   https://github.com/matrix-org/matrix-react-sdk-module-api
+
+</blockquote></details>
+
+<details><summary><h1>Prerequisites</h1></summary><blockquote>
+
+-   You must be part of the 2 Releasers GitHub groups:
+    -   <https://github.com/orgs/vector-im/teams/element-web-releasers>
+    -   <https://github.com/orgs/matrix-org/teams/element-web-releasers>
+-   You will need access to the **VPN** ([docs](https://gitlab.matrix.org/new-vector/internal/-/wikis/SRE/Tailscale)) to be able to follow the instructions under Deploy below.
+-   You will need the ability to **SSH** in to the production machines to be able to follow the instructions under Deploy below. Ensure that your SSH key has a non-empty passphrase, and you registered your SSH key with Ops. Log a ticket at https://github.com/matrix-org/matrix-ansible-private and ask for:
+    -   Two-factor authentication to be set up on your SSH key. (This is needed to get access to production).
+    -   SSH access to `horme` (staging.element.io and app.element.io)
+    -   Permission to sudo on horme as the user `element`
+-   You need "**jumphost**" configuration in your local `~/.ssh/config`. This should have been set up as part of your onboarding.
+
+</blockquote></details>
+
+<details><summary><h1>Overview</h1></summary><blockquote>
+
+```mermaid
+flowchart TD
+    P[[Prepare staging branches]]
+    P --> R1
+
+    subgraph Releasing
+        R1[[Releasing matrix-js-sdk]]
+        R2[[Releasing matrix-react-sdk]]
+        R3[[Releasing element-web]]
+        R4[[Releasing element-desktop]]
+
+        R1 --> R2 --> R3 --> R4
+    end
+
+    R4 --> D1
+
+    subgraph Deploying
+        D1[\Deploy staging.element.io/]
+        D2[\Check dockerhub/]
+        D3[\Deploy app.element.io/]
+        D4[\Check desktop package/]
+
+        D1 --> D2 --> D
+        D{FINAL?}
+        D -->|Yes| D3 --> D4
+    end
+
+    D -->|No| H1
+    D4 --> H1
+
+    subgraph Housekeeping
+        H1[\Update topics/]
+        H2[\Announce/]
+        H3[\Archive done column/]
+        H4[\Add diary entry/]
+        H5[\Renovate/]
+
+        H1 --> H2 --> H
+
+        H{FINAL?}
+        H -->|Yes| H3 --> H4 --> DONE
+        H -->|No| H5
+    end
+
+    DONE([You are done!])
+    H5 --> DONE
+```
+
+</blockquote></details>
+
+---
+
+# Preparation
+
+The goal of this stage is to get the code you want to ship onto the `staging` branch.
+There are multiple ways to accomplish this depending on the type of release you need to perform.
+
+For the first RC in a given release cycle the easiest way to prepare branches is using the
+[Cut branches automation](https://github.com/vector-im/element-web/actions/workflows/release_prepare.yml) -
+this will take `develop` and merge it into the `staging` on the chosen repositories.
+
+For subsequent RCs, if you need to include a change you may PR it directly to the `staging` branch or rely on the
+backport automation via labelling a PR to `develop` with `backport staging` which will cause a new PR to be opened
+which backports the requested change to the `staging` branch.
+
+For security, you may wish to merge the security advisory private fork or apply the patches manually and then push them directly to `staging`.
+It is worth noting that at the end of the Final/Hotfix/Security release `staging` is merged to `master` which is merged back into `develop` -
+this means that any commit which goes to `staging` will eventually make its way back to the default branch.
+
+-   [ ] The staging branch is prepared
+
+# Releasing
+
+Shortly after concluding the preparation stage (or pushing any changes to `staging` in general);
+a draft release will be automatically made on the 4 project repositories with suggested changelogs and version numbers.
+
+Review the draft releases created, check the version number makes sense and that the changelog contains everything you'd expect to.
+
+_Note: we should add a step here to write summaries atop the changelogs manually, or via AI_
+
+### Matrix JS SDK
+
+The first stop is the matrix-js-sdk; kick off a release using [the automation](https://github.com/matrix-org/matrix-js-sdk/actions/workflows/release.yml) - making sure to select the right type of release. For anything other than an RC: choose final. You should not need to ever switch off either of the Publishing options.
+
+-   [ ] matrix-js-sdk has been released & published to npm
+
+### Matrix React SDK
+
+The next stop is matrix-react-sdk; kick off a release using [the automation](https://github.com/matrix-org/matrix-react-sdk/actions/workflows/release.yml) - making sure to select the right type of release. For anything other than an RC: choose final. In the JS SDK version field enter the version of the JS SDK you wish to use, for typical releases including all the layers this would be the version released in the stage above.
+
+-   [ ] matrix-react-sdk has been released & published to npm
+
+### Element Web
+
+The next stop is element-web; kick off a release using [the automation](https://github.com/vector-im/element-web/actions/workflows/release.yml) - making sure to select the right type of release. For anything other than an RC: choose final. In the SDK version fields enter the versions you wish to use, for typical releases including all the layers this would be the versions released in the stages above.
+
+-   [ ] Element Web has been released
+
+### Element Desktop
+
+The next stop is element-desktop; kick off a release using [the automation](https://github.com/vector-im/element-desktop/actions/workflows/release.yml) - making sure to select the right type of release. For anything other than an RC: choose final. In the JS SDK version field enter the version of the JS SDK you wish to use, for typical releases including all the layers this would be the version released in the stage above.
+
+-   [ ] Element Desktop has been released
+
+# Deploying
+
+We ship the SDKs to npm, this happens as part of the release process.
+We ship Element Web to dockerhub, `*.element.io`, and packages.element.io.
+We ship Element Desktop to packages.element.io.
+
+-   [ ] Check that element-web has shipped to dockerhub
+-   [ ] Deploy staging.element.io. [See docs.](https://handbook.element.io/books/element-web-team/page/deploying-appstagingelementio)
+-   [ ] Test staging.element.io
+
+For final releases additionally do these steps:
+
+-   [ ] Deploy app.element.io. [See docs.](https://handbook.element.io/books/element-web-team/page/deploying-appstagingelementio)
+-   [ ] Test app.element.io
+-   [ ] Ensure Element Web package has shipped to packages.element.io
+-   [ ] Ensure Element Desktop packages have shipped to packages.element.io
+
+# Housekeeping
+
+We have some manual housekeeping to do in order to prepare for the next release.
+
+-   [ ] Update topics using [the automation](https://github.com/vector-im/element-web/actions/workflows/update-topics.yaml). It will autodetect the current latest version. Don't forget the date you supply should be e.g. September 5th (including the "th") for the script to work.
+-   [ ] Announce the release in [#element-web-announcements:matrix.org](https://matrix.to/#/#element-web-announcements:matrix.org)
+
+<details><summary>(show)</summary>
+
+With wording like:
+
+> Element Web v1.11.24 is here!
+>
+> This version adds ... and fixes bugs ...
+>
+> Check it out at app.element.io, in Element Desktop, or from Docker Hub. Changelog and more details at https://github.com/vector-im/element-web/releases/tag/v1.11.24
+
+</details>
+
+For the first RC of a given release cycle do these steps:
+
+-   [ ] Go to the [matrix-js-sdk Renovate dashboard](https://github.com/matrix-org/matrix-js-sdk/issues/2406) and click the checkbox to create/update its PRs.
+
+-   [ ] Go to the [matrix-react-sdk Renovate dashboard](https://github.com/matrix-org/matrix-react-sdk/issues/9667) and click the checkbox to create/update its PRs.
+
+-   [ ] Go to the [element-web Renovate dashboard](https://github.com/vector-im/element-web/issues/22941) and click the checkbox to create/update its PRs.
+
+-   [ ] Go to the [element-desktop Renovate dashboard](https://github.com/vector-im/element-desktop/issues/465) and click the checkbox to create/update its PRs.
+
+-   [ ] Later, check back and merge the PRs that succeeded to build. The ones that failed will get picked up by the [maintainer](https://docs.google.com/document/d/1V5VINWXATMpz9UBw4IKmVVB8aw3CxM0Jt7igtHnDfSk/edit#).
+
+For final releases additionally do these steps:
+
+-   [ ] Archive done column on the [team board](https://github.com/orgs/vector-im/projects/67/views/34) _Note: this should be automated_
+-   [ ] Add entry to the [milestones diary](https://docs.google.com/document/d/1cpRFJdfNCo2Ps6jqzQmatzbYEToSrQpyBug0aP_iwZE/edit#heading=h.6y55fw4t283z). The document says only to add significant releases, but we add all of them just in case.