Use buildx

This is helpful to determine if your alerts are valid before an actual failure

.drone.yml

@@ -60,51 +60,15 @@ steps:
     when:
       event: tag
 
-  - name: push image - arm
+  - name: Build and publish docker images
-    image: plugins/docker
+    image: thegeeklab/drone-docker-buildx
     settings:
       repo: iamthefij/minitor-go
       auto_tag: true
-      auto_tag_suffix: linux-arm
+      platforms:
-      username:
+        - linux/amd64
-        from_secret: docker_username
+        - linux/arm64
-      password:
+        - linux/arm
-        from_secret: docker_password
-      build_args:
-        - ARCH=arm
-        - REPO=arm32v7
-
-  - name: push image - arm64
-    image: plugins/docker
-    settings:
-      repo: iamthefij/minitor-go
-      auto_tag: true
-      auto_tag_suffix: linux-arm64
-      username:
-        from_secret: docker_username
-      password:
-        from_secret: docker_password
-      build_args:
-        - ARCH=arm64
-        - REPO=arm64v8
-
-  - name: push image - amd64
-    image: plugins/docker
-    settings:
-      repo: iamthefij/minitor-go
-      auto_tag: true
-      auto_tag_suffix: linux-amd64
-      username:
-        from_secret: docker_username
-      password:
-        from_secret: docker_password
-
-  - name: publish manifest
-    image: plugins/manifest
-    settings:
-      spec: manifest.tmpl
-      auto_tag: true
-      ignore_missing: true
       username:
         from_secret: docker_username
       password:

Dockerfile

@@ -1,11 +1,10 @@
-ARG REPO=library
+FROM alpine:3.18
-FROM ${REPO}/alpine:3.18
 
 RUN mkdir /app
 WORKDIR /app/
 
 # Add common checking tools
-RUN apk --no-cache add bash=~5 curl=~8 jq=~1 bind-tools=~9 tzdata~=2023c
+RUN apk --no-cache add bash=~5 curl=~8 jq=~1 bind-tools=~9 tzdata~=2024a
 
 # Add minitor user for running as non-root
 RUN addgroup -S minitor && adduser -S minitor -G minitor
@@ -15,8 +14,9 @@ COPY ./scripts /app/scripts
 RUN chmod -R 755 /app/scripts
 
 # Copy minitor in
-ARG ARCH=amd64
+ARG TARGETOS
-COPY ./dist/minitor-linux-${ARCH} ./minitor
+ARG TARGETARCH
+COPY ./dist/minitor-${TARGETOS}-${TARGETARCH} ./minitor
 
 # Drop to non-root user
 USER minitor

Dockerfile.multi-stage

@@ -1,4 +1,3 @@
-ARG REPO=library
 FROM golang:1.20 AS builder
 
 RUN mkdir /app
@@ -9,12 +8,13 @@ RUN go mod download
 
 COPY ./*.go /app/
 
-ARG ARCH=amd64
+ARG TARGETOS
+ARG TARGETARCH
 ARG VERSION=dev
-ENV CGO_ENABLED=0 GOOS=linux GOARCH=${ARCH}
+ENV CGO_ENABLED=0 GOOS=$TARGETOS GOARCH=${TARGETARCH}
 RUN go build -ldflags "-X main.version=${VERSION}" -a -installsuffix nocgo -o minitor .
 
-FROM ${REPO}/alpine:3.18
+FROM alpine:3.18
 RUN mkdir /app
 WORKDIR /app/
 
@@ -22,7 +22,7 @@ WORKDIR /app/
 COPY --from=builder /app/minitor .
 
 # Add common checking tools
-RUN apk --no-cache add bash=~5 curl=~8 jq=~1 bind-tools=~9 tzdata~=2023c
+RUN apk --no-cache add bash=~5 curl=~8 jq=~1 bind-tools=~9 tzdata~=2024a
 
 # Add minitor user for running as non-root
 RUN addgroup -S minitor && adduser -S minitor -G minitor

Makefile

@@ -79,11 +79,11 @@ $(TARGET_ALIAS):
 # Arch specific docker build targets
 .PHONY: docker-build-arm
 docker-build-arm: dist/minitor-linux-arm
-	docker build --build-arg REPO=arm32v7 --build-arg ARCH=arm . -t ${DOCKER_TAG}-linux-arm
+	docker build --platform linux/arm . -t ${DOCKER_TAG}-linux-arm
 
 .PHONY: docker-build-arm64
 docker-build-arm64: dist/minitor-linux-arm64
-	docker build --build-arg REPO=arm64v8 --build-arg ARCH=arm64 . -t ${DOCKER_TAG}-linux-arm64
+	docker build  --platform linux/arm64 . -t ${DOCKER_TAG}-linux-arm64
 
 # Cross run on host architechture
 .PHONY: docker-run-arm

README.md

@@ -118,6 +118,16 @@ To provide flexible formatting, the following non-standard functions are availab
 
 For more information, check out the [Go documentation for the time module](https://pkg.go.dev/time@go1.20.7#pkg-constants).
 
+#### Running alerts on startup
+
+It's not the best feeling to find out your alerts are broken when you're expecting to be alerted about another failure. To avoid this and provide early insight into broken alerts, it is possible to specify a list of alerts to run when Minitor starts up. This can be done using the command line flag `-startup-alerts`. This flag accepts a comma separated list of strings and will run a test of each of those alerts. Minitor will then respond as it typically does for any failed alert. This can be used to allow you time to correct when initially launching, and to allow schedulers to more easily detect a failed deployment of Minitor.
+
+Eg.
+
+```bash
+minitor -startup-alerts=log_down,log_up -config ./config.yml
+```
+
 ### Metrics
 
 Minitor supports exporting metrics for [Prometheus](https://prometheus.io/). Prometheus is an open source tool for reading and querying metrics from different sources. Combined with another tool, [Grafana](https://grafana.com/), it allows building of charts and dashboards. You could also opt to just use Minitor to log check results, and instead do your alerting with Grafana.

main.go

@@ -92,7 +92,7 @@ func checkMonitors(config *Config) error {
 	return nil
 }
 
-func sendFirstRunAlerts(config *Config, alertNames []string) error {
+func sendStartupAlerts(config *Config, alertNames []string) error {
 	for _, alertName := range alertNames {
 		var err error
 
@@ -123,7 +123,7 @@ func sendFirstRunAlerts(config *Config, alertNames []string) error {
 func main() {
 	showVersion := flag.Bool("version", false, "Display the version of minitor and exit")
 	configPath := flag.String("config", "config.yml", "Alternate configuration path (default: config.yml)")
-	firstRunAlerts := flag.String("first-run-alerts", "", "List of alerts to run on startup. This can help determine unhealthy alerts early on. (default \"\")")
+	startupAlerts := flag.String("startup-alerts", "", "List of alerts to run on startup. This can help determine unhealthy alerts early on. (default \"\")")
 
 	flag.BoolVar(&slog.DebugLevel, "debug", false, "Enables debug logs (default: false)")
 	flag.BoolVar(&ExportMetrics, "metrics", false, "Enables prometheus metrics exporting (default: false)")
@@ -149,12 +149,12 @@ func main() {
 		go ServeMetrics()
 	}
 
-	if *firstRunAlerts != "" {
+	if *startupAlerts != "" {
-		alertNames := strings.Split(*firstRunAlerts, ",")
+		alertNames := strings.Split(*startupAlerts, ",")
 
-		err = sendFirstRunAlerts(&config, alertNames)
+		err = sendStartupAlerts(&config, alertNames)
 
-		slog.OnErrPanicf(err, "Error running first run alerts")
+		slog.OnErrPanicf(err, "Error running startup alerts")
 	}
 
 	// Start main loop

main_test.go

@@ -137,22 +137,22 @@ func TestCheckMonitors(t *testing.T) {
 
 func TestFirstRunAlerts(t *testing.T) {
 	cases := []struct {
-		config         Config
+		config        Config
-		expectErr      bool
+		expectErr     bool
-		firstRunAlerts []string
+		startupAlerts []string
-		name           string
+		name          string
 	}{
 		{
-			config:         Config{},
+			config:        Config{},
-			expectErr:      false,
+			expectErr:     false,
-			firstRunAlerts: []string{},
+			startupAlerts: []string{},
-			name:           "Empty",
+			name:          "Empty",
 		},
 		{
-			config:         Config{},
+			config:        Config{},
-			expectErr:      true,
+			expectErr:     true,
-			firstRunAlerts: []string{"missing"},
+			startupAlerts: []string{"missing"},
-			name:           "Unknown",
+			name:          "Unknown",
 		},
 		{
 			config: Config{
@@ -162,9 +162,9 @@ func TestFirstRunAlerts(t *testing.T) {
 					},
 				},
 			},
-			expectErr:      false,
+			expectErr:     false,
-			firstRunAlerts: []string{"good"},
+			startupAlerts: []string{"good"},
-			name:           "Successful alert",
+			name:          "Successful alert",
 		},
 		{
 			config: Config{
@@ -175,9 +175,9 @@ func TestFirstRunAlerts(t *testing.T) {
 					},
 				},
 			},
-			expectErr:      true,
+			expectErr:     true,
-			firstRunAlerts: []string{"bad"},
+			startupAlerts: []string{"bad"},
-			name:           "Failed alert",
+			name:          "Failed alert",
 		},
 	}
 
@@ -187,7 +187,7 @@ func TestFirstRunAlerts(t *testing.T) {
 			t.Errorf("sendFirstRunAlerts(%s): unexpected error reading config: %v", c.name, err)
 		}
 
-		err = sendFirstRunAlerts(&c.config, c.firstRunAlerts)
+		err = sendStartupAlerts(&c.config, c.startupAlerts)
 		if err == nil && c.expectErr {
 			t.Errorf("sendFirstRunAlerts(%s): Expected error, the code did not error", c.name)
 		} else if err != nil && !c.expectErr {

manifest.tmpl

@@ -1,25 +0,0 @@
-image: iamthefij/minitor-go:{{#if build.tag}}{{trimPrefix "v" build.tag}}{{else}}latest{{/if}}
-{{#if build.tags}}
-tags:
-{{#each build.tags}}
-  - {{this}}
-{{/each}}
-{{/if}}
-manifests:
-  -
-    image: iamthefij/minitor-go:{{#if build.tag}}{{trimPrefix "v" build.tag}}-{{/if}}linux-amd64
-    platform:
-      architecture: amd64
-      os: linux
-  -
-    image: iamthefij/minitor-go:{{#if build.tag}}{{trimPrefix "v" build.tag}}-{{/if}}linux-arm64
-    platform:
-      architecture: arm64
-      os: linux
-      variant: v8
-  -
-    image: iamthefij/minitor-go:{{#if build.tag}}{{trimPrefix "v" build.tag}}-{{/if}}linux-arm
-    platform:
-      architecture: arm
-      os: linux
-      variant: v7