Add CI/CD pipeline

The binary doubles as its own healthcheck client via the SDK's
-healthcheck flag, so the probe works in the scratch image
(no shell, no curl, no wget).

.drone-manifest.yml

@@ -0,0 +1,22 @@
+image: happydomain/checker-ping:{{#if build.tag}}{{trimPrefix "v" build.tag}}{{else}}latest{{/if}}
+{{#if build.tags}}
+tags:
+{{#each build.tags}}
+  - {{this}}
+{{/each}}
+{{/if}}
+manifests:
+  - image: happydomain/checker-ping:{{#if build.tag}}{{trimPrefix "v" build.tag}}-{{/if}}linux-amd64
+    platform:
+      architecture: amd64
+      os: linux
+  - image: happydomain/checker-ping:{{#if build.tag}}{{trimPrefix "v" build.tag}}-{{/if}}linux-arm64
+    platform:
+      architecture: arm64
+      os: linux
+      variant: v8
+  - image: happydomain/checker-ping:{{#if build.tag}}{{trimPrefix "v" build.tag}}-{{/if}}linux-arm
+    platform:
+      architecture: arm
+      os: linux
+      variant: v7

.drone.yml

@@ -0,0 +1,187 @@
+---
+kind: pipeline
+type: docker
+name: build-amd64
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+  - name: checker build
+    image: golang:1-alpine
+    commands:
+      - apk add --no-cache git make
+      - make
+    environment:
+      CHECKER_VERSION: "${DRONE_BRANCH}-${DRONE_COMMIT}"
+      CGO_ENABLED: 0
+    when:
+      event:
+        exclude:
+          - tag
+
+  - name: checker build tag
+    image: golang:1-alpine
+    commands:
+      - apk add --no-cache git make
+      - make
+    environment:
+      CHECKER_VERSION: "${DRONE_SEMVER}"
+      CGO_ENABLED: 0
+    when:
+      event:
+        - tag
+
+  - name: publish on Docker Hub
+    image: plugins/docker
+    settings:
+      repo: happydomain/checker-ping
+      auto_tag: true
+      auto_tag_suffix: ${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH}
+      dockerfile: Dockerfile
+      build_args:
+        - CHECKER_VERSION=${DRONE_BRANCH}-${DRONE_COMMIT}
+      username:
+        from_secret: docker_username
+      password:
+        from_secret: docker_password
+    when:
+      event:
+        exclude:
+          - tag
+
+  - name: publish on Docker Hub (tag)
+    image: plugins/docker
+    settings:
+      repo: happydomain/checker-ping
+      auto_tag: true
+      auto_tag_suffix: ${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH}
+      dockerfile: Dockerfile
+      build_args:
+        - CHECKER_VERSION=${DRONE_SEMVER}
+      username:
+        from_secret: docker_username
+      password:
+        from_secret: docker_password
+    when:
+      event:
+        - tag
+
+trigger:
+  branch:
+    exclude:
+      - renovate/*
+  event:
+    - cron
+    - push
+    - tag
+
+---
+kind: pipeline
+type: docker
+name: build-arm64
+
+platform:
+  os: linux
+  arch: arm64
+
+steps:
+  - name: checker build
+    image: golang:1-alpine
+    commands:
+      - apk add --no-cache git make
+      - make
+    environment:
+      CHECKER_VERSION: "${DRONE_BRANCH}-${DRONE_COMMIT}"
+      CGO_ENABLED: 0
+    when:
+      event:
+        exclude:
+          - tag
+
+  - name: checker build tag
+    image: golang:1-alpine
+    commands:
+      - apk add --no-cache git make
+      - make
+    environment:
+      CHECKER_VERSION: "${DRONE_SEMVER}"
+      CGO_ENABLED: 0
+    when:
+      event:
+        - tag
+
+  - name: publish on Docker Hub
+    image: plugins/docker
+    settings:
+      repo: happydomain/checker-ping
+      auto_tag: true
+      auto_tag_suffix: ${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH}
+      dockerfile: Dockerfile
+      build_args:
+        - CHECKER_VERSION=${DRONE_BRANCH}-${DRONE_COMMIT}
+      username:
+        from_secret: docker_username
+      password:
+        from_secret: docker_password
+    when:
+      event:
+        exclude:
+          - tag
+
+  - name: publish on Docker Hub (tag)
+    image: plugins/docker
+    settings:
+      repo: happydomain/checker-ping
+      auto_tag: true
+      auto_tag_suffix: ${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH}
+      dockerfile: Dockerfile
+      build_args:
+        - CHECKER_VERSION=${DRONE_SEMVER}
+      username:
+        from_secret: docker_username
+      password:
+        from_secret: docker_password
+    when:
+      event:
+        - tag
+
+trigger:
+  event:
+    - cron
+    - push
+    - tag
+
+---
+kind: pipeline
+name: docker-manifest
+
+platform:
+  os: linux
+  arch: arm64
+
+steps:
+  - name: publish on Docker Hub
+    image: plugins/manifest
+    settings:
+      auto_tag: true
+      ignore_missing: true
+      spec: .drone-manifest.yml
+      username:
+        from_secret: docker_username
+      password:
+        from_secret: docker_password
+
+trigger:
+  branch:
+    exclude:
+      - renovate/*
+  event:
+    - cron
+    - push
+    - tag
+
+depends_on:
+  - build-amd64
+  - build-arm64

Dockerfile

@@ -6,9 +6,12 @@ WORKDIR /src
 COPY go.mod go.sum ./
 RUN go mod download
 COPY . .
-RUN CGO_ENABLED=0 go build -ldflags "-X main.Version=${CHECKER_VERSION}" -o /checker-ping .
+RUN CGO_ENABLED=0 go build -tags standalone -ldflags "-X main.Version=${CHECKER_VERSION}" -o /checker-ping .
 
 FROM scratch
 COPY --from=builder /checker-ping /checker-ping
+USER 65534:65534
 EXPOSE 8080
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+  CMD ["/checker-ping", "-healthcheck"]
 ENTRYPOINT ["/checker-ping"]

LICENSE

@@ -0,0 +1,682 @@
+happyDomain Licensing
+
+SOFTWARE LICENSING
+
+You may be licensed to use source code to create compiled versions not produced
+by the happyDNS team in one of two ways:
+
+1. Under the AGPL v3, subject to the exceptions outlined in this policy;
+2. Under a commercial license available from the happyDNS team by contacting
+   contact@happydns.org.
+
+happyDNS and happyDomain TRADEMARK GUIDELINES
+
+Your use of the mark happyDNS and happyDomain is subject to the happyDNS team's
+prior written approval and our organization’s Trademark Standards of Use at
+http://www.happydomain.org/trademark-standards-of-use/. For trademark approval
+or any questions you have about using these trademarks, please email
+contact@happydns.org
+
+------------------------------------------------------------------------------------------------------------------------------
+
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
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+menu, a prominent item in the list meets this criterion.
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