ci: Build container image

In addition to building an RPM package for regular Fedora machines, we
now build a container image containing a statically-linked `sshca-cli`
executable.

.containerignore

@@ -0,0 +1,4 @@
+*
+!src
+!Cargo.lock
+!Cargo.toml

Containerfile

@@ -0,0 +1,18 @@
+FROM docker.io/library/rust:1.73-alpine AS build
+
+COPY . /build
+
+WORKDIR /build
+
+RUN --mount=type=cache,target=/var/cache \
+	apk add --no-cache g++ \
+	&& :
+
+RUN cargo build --release --no-default-features --features rustls \
+	&& strip target/release/sshca-cli
+
+FROM scratch
+
+COPY --from=build /build/target/release/sshca-cli /
+
+ENTRYPOINT ["/sshca-cli"]

ci/Jenkinsfile

@@ -2,7 +2,7 @@ pipeline {
     agent none
 
     stages {
-        stage('SSHCA CLI') {
+        stage('RPM') {
             matrix {
                 axes {
                     axis {
@@ -16,7 +16,7 @@ pipeline {
                 }
 
                 stages {
-                    stage('CLI') {
+                    stage('Build RPM') {
                         agent {
                             kubernetes {
                                 yamlFile 'ci/podTemplate.yaml'
@@ -79,8 +79,73 @@ pipeline {
                         }
                     }
                 }
+            }
+        }
+
+        stage('Build Container') {
+            matrix {
+                axes {
+                    axis {
+                        name 'ARCH'
+                        values 'amd64', 'arm64'
+                    }
+                }
+                stages {
+                    stage('Container') {
+                        agent {
+                            kubernetes {
+                                yamlFile 'ci/podTemplate-container.yaml'
+                                yamlMergeStrategy merge()
+                                defaultContainer 'buildah'
+                                nodeSelector "kubernetes.io/arch=${ARCH}"
+                            }
+                        }
+
+                        stages {
+                            stage('Build') {
+                                steps {
+                                    sh '. ci/build-container.sh'
+                                    stash name: env.ARCH, includes: "*.oci.tar"
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        stage('Publish Container') {
+            agent {
+                kubernetes {
+                    yamlFile 'ci/podTemplate-container.yaml'
+                    yamlMergeStrategy merge()
+                    defaultContainer 'buildah'
+                }
+            }
+
+            environment {
+                REGISTRY_AUTH_FILE = "${env.WORKSPACE_TMP}/auth.json"
+            }
+
+            steps {
+                unstash 'amd64'
+                unstash 'arm64'
+                withCredentials([usernamePassword(
+                    credentialsId: 'jenkins-packages',
+                    usernameVariable: 'BUILDAH_USERNAME',
+                    passwordVariable: 'BUILDAH_PASSWORD',
+                )]) {
+                    sh """
+                        buildah login \
+                        --username \${BUILDAH_USERNAME} \
+                        --password \${BUILDAH_PASSWORD} \
+                        git.pyrocufflink.net
+                    """
+                }
+                sh '. ci/publish-container.sh'
+            }
+        }
+
 
     }
 }
-    }
-}

ci/build-container.sh

@@ -0,0 +1,6 @@
+. ci/common.sh
+
+buildah build -t "${IMAGE_NAME}:${TAG}" .
+buildah push \
+    "${IMAGE_NAME}:${TAG}" \
+    oci-archive:"${PWD}/${NAME}-${ARCH}.oci.tar:${IMAGE_NAME}:${TAG}"

ci/common.sh

@@ -0,0 +1,13 @@
+escape_name() {
+    echo "$1" \
+        | tr A-Z a-z \
+        | sed -e 's/[^a-zA-Z0-9._-]/-/g' -e 's/^[.-]/_/'
+}
+
+REGISTRY_URL=git.pyrocufflink.net
+NAMESPACE=containerimages
+NAME="${JOB_NAME#*/}"
+NAME=$(escape_name "${NAME%/*}")
+TAG=$(escape_name "${BRANCH_NAME}")
+
+IMAGE_NAME="${REGISTRY_URL}/${NAMESPACE}/${NAME}"

ci/podTemplate-container.yaml

@@ -0,0 +1,19 @@
+spec:
+  containers:
+  - name: buildah
+    image: quay.io/containers/buildah:v1
+    command:
+    - cat
+    stdin: true
+    tty: true
+    securityContext:
+      capabilities:
+        add:
+        - SYS_ADMIN
+        - MKNOD
+        - SYS_CHROOT
+        - SETFCAP
+    resources:
+      limits:
+        github.com/fuse: 1
+  hostUsers: false

ci/publish-container.sh

@@ -0,0 +1,15 @@
+. ci/common.sh
+
+buildah manifest create "${IMAGE_NAME}:${TAG}"
+for arch in amd64 arm64; do
+    buildah manifest add "${IMAGE_NAME}:${TAG}" \
+        oci-archive:"${PWD}/${NAME}-${arch}.oci.tar:${IMAGE_NAME}:${TAG}"
+done
+
+buildah manifest push --all "${IMAGE_NAME}:${TAG}" \
+    "docker://${IMAGE_NAME}:${TAG}-${BUILD_NUMBER}"
+buildah manifest push "${IMAGE_NAME}:${TAG}" "docker://${IMAGE_NAME}:${TAG}"
+if [ ${BRANCH_NAME} = master ]; then
+    buildah manifest push "${IMAGE_NAME}:${TAG}" \
+        "docker://${IMAGE_NAME}:latest"
+fi