GitHub output adaptor

Dockerfile

@@ -5,6 +5,8 @@ COPY . .
 RUN set -eux; \
   export GOROOT="$(go env GOROOT)"; \
   make build
+  make build-action
 FROM scratch
 COPY --from=build /go/src/github.com/josephburnett/jd/release/jd /jd
+COPY --from=build /go/src/github.com/josephburnett/jd/release/jd-acion /jd-action
 ENTRYPOINT ["/jd"]

Makefile

@@ -27,6 +27,10 @@ build-web :
 serve : pack-web
 	go run -tags include_web main.go -port 8080
 
+.PHONY : build-action
+build-action :
+	CGO_ENABLED=0 go build ./github-action -o jd-action main.go
+
 .PHONY : release-build
 release-build : check-env check-version check-dirty build-all build-docker
 	@echo

github-action/main.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"os"
+	"os/exec"
+	"strconv"
+)
+
+func main() {
+	outputFile := os.Getenv("GITHUB_OUTPUT")
+	if outputFile == "" {
+		fmt.Printf("GITHUB_OUTPUT not set. Are you running in GitHub CI?")
+		os.Exit(2)
+	}
+	file, err := os.OpenFile(outputFile, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(2)
+	}
+	defer file.Close()
+	cmd := exec.Command("jd", os.Args[2:]...)
+	data, _ := cmd.CombinedOutput()
+	exitCode := cmd.ProcessState.ExitCode()
+	delimiter := strconv.Itoa(rand.Int())
+	file.WriteString("output<<" + delimiter + "\n")
+	file.WriteString(string(data))
+	file.WriteString("delimiter\n")
+	os.Exit(exitCode)
+}