Move Momentum docs to the private momentum-docs submodule

.example.env.local

@@ -2,6 +2,7 @@ NEXT_PUBLIC_GTM_ID=123
 NEXT_PUBLIC_ALGOLIA_APP_ID=
 NEXT_PUBLIC_ALGOLIA_SEARCH_API_KEY=
 ALGOLIA_SEARCH_ADMIN_KEY=
+NEXT_PUBLIC_ALGOLIA_MOMENTUM_INDEX=
 
 # According to https://github.com/vercel/next.js/issues/3605#issuecomment-370250206, nextjs only 
 # supports 'production' and 'development' envs out of the box, so we have to create a ENV 

.github/actions/momentum-docs/action.yml

@@ -0,0 +1,27 @@
+name: Check out the Momentum docs
+description: Fetches the private SparkPost/momentum-docs submodule at content/momentum, which every site build needs.
+
+inputs:
+  ssh-key:
+    description: Private half of a read-only deploy key on SparkPost/momentum-docs.
+    required: true
+
+runs:
+  using: composite
+  steps:
+    # A separate step rather than actions/checkout's ssh-key input, which
+    # would also use the momentum-docs key to fetch this repository.
+    - shell: bash
+      env:
+        SSH_KEY: ${{ inputs.ssh-key }}
+      run: |
+        # Pull requests from forks get no secrets.
+        if [ -z "$SSH_KEY" ]; then
+          echo "::error::MOMENTUM_DOCS_SSH_KEY is not available, so content/momentum cannot be fetched"
+          exit 1
+        fi
+        key="$RUNNER_TEMP/momentum-docs-key"
+        trap 'rm -f "$key"' EXIT
+        (umask 077 && printf '%s\n' "$SSH_KEY" > "$key")
+        GIT_SSH_COMMAND="ssh -i '$key' -o IdentitiesOnly=yes -o StrictHostKeyChecking=accept-new" \
+          git submodule update --init content/momentum

.github/workflows/cypress.yml

@@ -23,6 +23,9 @@ jobs:
           node-version: ${{ matrix.node-version }}
       - name: Checkout repository
         uses: actions/checkout@v4
+      - uses: ./.github/actions/momentum-docs
+        with:
+          ssh-key: ${{ secrets.MOMENTUM_DOCS_SSH_KEY }}
       - name: Cypress run
         uses: cypress-io/github-action@v6
         with:

.github/workflows/index.yml

@@ -26,6 +26,9 @@ jobs:
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
       - uses: actions/checkout@v4
+      - uses: ./.github/actions/momentum-docs
+        with:
+          ssh-key: ${{ secrets.MOMENTUM_DOCS_SSH_KEY }}
 
       - name: Setup Node.js
         uses: actions/setup-node@v4

.github/workflows/lighthouse.yml

@@ -16,6 +16,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
+      - uses: ./.github/actions/momentum-docs
+        with:
+          ssh-key: ${{ secrets.MOMENTUM_DOCS_SSH_KEY }}
       - uses: actions/cache@v4
         with:
           path: ~/.npm

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "content/momentum"]
+	path = content/momentum
+	url = git@github.com:SparkPost/momentum-docs.git

README.md

@@ -6,7 +6,11 @@ This repo contains the SparkPost and Momentum documentation published at https:/
 
 SparkPost documentation is located in the `content/docs/` directory.
 
-Momentum documentation is located in the `content/momentum/` directory.
+Momentum documentation is maintained in the private repository
+[SparkPost/momentum-docs](https://github.com/SparkPost/momentum-docs) and included here as a git
+submodule at `content/momentum/`. The submodule commit is what docs.sparkpost.com/momentum publishes.
+Edit Momentum docs there; to publish a release, move the submodule to that release's tag in this
+repository.
 
 All content is formatted in [Markdown](https://daringfireball.net/projects/markdown/syntax) and version control is managed by Github.
 
@@ -157,9 +161,12 @@ _**This is not a required step in contributing to the documentation**_
 
 ### Installation
 
-Navigate in your terminal to the root directory (`support-docs/` or whatever you named it) and install all dependencies:
+Navigate in your terminal to the root directory (`support-docs/` or whatever you named it), fetch the
+Momentum docs submodule (this needs read access to SparkPost/momentum-docs; the site does not build
+without it) and install all dependencies:
 
 ```
+git submodule update --init
 npm install
 ```
 
@@ -200,6 +207,10 @@ NEXT_PUBLIC_ALGOLIA_APP_ID=
 NEXT_PUBLIC_ALGOLIA_SEARCH_API_KEY=
 ALGOLIA_SEARCH_ADMIN_KEY=
 
+# Optional. Searches, and with build:index:momentum rebuilds from scratch, this Momentum index
+# instead of next_momentum_documentation. The momentum-docs preview builds set it.
+NEXT_PUBLIC_ALGOLIA_MOMENTUM_INDEX=
+
 # According to https://github.com/vercel/next.js/issues/3605#issuecomment-370250206, nextjs only
 # supports 'production' and 'development' envs out of the box, so we have to create a ENV
 # variable if we want a 'test' specific environment

components/site/algolia/search.tsx

@@ -6,7 +6,7 @@ import SearchBox from 'components/site/algolia/searchBox';
 import SearchResults from 'components/site/algolia/results';
 
 type SearchProps = {
-  indexName: 'next_momentum_documentation' | 'next_support_documentation' | 'next_analyst_documentation';
+  indexName: string;
 };
 
 const Search = (props: SearchProps): JSX.Element => {

components/site/header.tsx

@@ -5,6 +5,7 @@ import { Menu } from '@sparkpost/matchbox-icons';
 import Logo from 'components/site/logo';
 import Search from 'components/site/algolia/search';
 import HeaderButtons from 'components/site/headerButtons';
+import { momentumIndexName } from 'lib/algoliaIndexes';
 import styled from 'styled-components';
 
 const StyledButton = styled.button`
@@ -22,7 +23,7 @@ const Header = (props: HeaderProps) => {
   const category = asPath.split('/')[1];
   let searchBox = (<Search indexName="next_support_documentation" />);
   if (category === 'momentum') {
-    searchBox = (<Search indexName="next_momentum_documentation" />);
+    searchBox = (<Search indexName={momentumIndexName()} />);
   } else if (category === 'analyst') {
     searchBox = (<Search indexName="next_analyst_documentation" />);
   }