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README.md

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+Mochi Test Build Action
+=======================
+
+This action is meant to be used by the Mochi collection of packages
+to test that they can be built using Spack (their latest version or
+any other specified version). The following is a minimal example of
+github workflow that tests every day that the latest version of the
+package can be built with the develop branch of Spack.
+
+```yaml
+name: Build the latest release using Spack
+
+on:
+  workflow_dispatch: {}
+  schedule:
+  - cron: "0 0 * * *"
+
+jobs:
+  build:
+    runs-on: ubuntu-22.04
+    name: Build the latest version of the package
+    steps:
+    - uses: actions/checkout@v4
+    - uses: mochi-hpc/mochi-test-build-action@main
+```
+
+This workflow will infer the name of the package to install from the
+name of the repository running the action (for instance if mochi-hpc/mochi-margo
+runs the action, then the action will install mochi-margo).
+
+Here is a more complete version of the workflow, specifying all the possible
+inputs:
+
+```yaml
+name: Build the latest release using Spack
+
+on:
+  workflow_dispatch: {}
+  schedule:
+  - cron: "0 0 * * *"
+
+jobs:
+  build:
+    runs-on: ubuntu-22.04
+    name: Build the latest version of the package
+    steps:
+    - uses: actions/checkout@v4
+    - uses: mochi-hpc/mochi-test-build-action@main
+      with:
+        # The package name will default to the name of the repository
+        package-name: mochi-margo
+        # The version will default to whatever is the preferred version for the package
+        # Note that the "@" is required before the version
+        package-version: '@1.2.3'
+        # If specified, build-cache-token should be set to ${{ secrets.GITHUB_TOKEN }},
+        # this will make the workflow push any dependencies built to the mochi-spack-buildcache
+        # after a successful installation of the package
+        build-cache-token: ${{ secrets.GITHUB_TOKEN }}
+        # Version of spack to use (default is the develop branch)
+        spack-version: v0.22.1
+        # Reference (main or a commit hash) to use for mochi-spack-packages (default is main)
+        mochi-spack-packages-version: main
+```
+