Check flag and housekeeping

.gitignore

@@ -10,3 +10,7 @@
 
 # Output of the go coverage tool, specifically when used with LiteIDE
 *.out
+
+# Build output
+/github_status
+/dist/

Makefile

@@ -4,7 +4,7 @@ build:
 check:
 	golangci-lint run
 
-release:
+snapshot:
 	goreleaser release --snapshot --clean
 
-.PHONY: build check release
+.PHONY: build check snapshot

README.md

@@ -1,4 +1,57 @@
 # github_status
-GitHub Status
 
 ![example workflow](https://github.com/mikemadden42/github_status/actions/workflows/go.yml/badge.svg)
+
+Print the current status of each GitHub component, from
+[githubstatus.com](https://www.githubstatus.com).
+
+## Install
+
+```sh
+go install github.com/mikemadden42/github_status@latest
+```
+
+## Usage
+
+```sh
+github_status
+```
+
+```
+All Systems Operational
+
+Git Operations                                              operational
+Webhooks                                                    operational
+API Requests                                                operational
+Issues                                                      operational
+Pull Requests                                               operational
+Actions                                                     operational
+Packages                                                    operational
+Pages                                                       operational
+Copilot                                                     operational
+Codespaces                                                  operational
+Copilot AI Model Providers                                  operational
+```
+
+Statuses are colored: green for operational, yellow for degraded performance or
+partial outage, red for major outage and blue for maintenance.
+
+### Scripting
+
+With `-check`, `github_status` exits with status 1 if any component is not
+operational:
+
+```sh
+github_status -check || echo "GitHub is having problems"
+```
+
+It also exits with status 1 if the status page can't be reached.
+
+## Development
+
+```sh
+go test ./...
+make check      # golangci-lint
+make build      # goreleaser snapshot build into dist/
+make snapshot   # full goreleaser snapshot release (local only, nothing is published)
+```

TODO.md

@@ -30,7 +30,7 @@
 - [x] Use `json.NewDecoder(resp.Body).Decode` instead of `io.ReadAll` + `Unmarshal`
 - [x] Use the readable URL `https://www.githubstatus.com/api/v2/summary.json`
 - [x] Add a package comment (revive)
-- [ ] Exit non-zero when any component isn't operational
+- [x] Exit non-zero when any component isn't operational (with `-check`)
 
 ## Tests / CI
 
@@ -45,7 +45,7 @@
 
 ## Housekeeping
 
-- [ ] Delete the Jenkinsfile unless Jenkins is in use (build-only, no tests, echo-only post blocks)
-- [ ] `make release` uses `--snapshot`, so it never publishes. Rename the target or drop the flag
-- [ ] Add `dist/` and `github_status` to `.gitignore`
-- [ ] Expand the README with usage, install and example output
+- [x] Delete the Jenkinsfile unless Jenkins is in use (build-only, no tests, echo-only post blocks)
+- [x] `make release` uses `--snapshot`, so it never publishes. Renamed to `make snapshot`
+- [x] Add `dist/` and `github_status` to `.gitignore`
+- [x] Expand the README with usage, install and example output

github_status.go

@@ -6,6 +6,7 @@ package main
 
 import (
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"net/http"
@@ -29,9 +30,16 @@ type summary struct {
 const summaryURL = "https://www.githubstatus.com/api/v2/summary.json"
 
 func main() {
+	check := flag.Bool("check", false, "exit with status 1 if any component is not operational")
+	flag.Parse()
+
 	s, err := fetch(summaryURL)
 	checkErr(err)
 	checkErr(render(os.Stdout, s))
+
+	if *check && !operational(s) {
+		os.Exit(1)
+	}
 }
 
 // fetch retrieves and decodes the status page summary at url.
@@ -76,6 +84,17 @@ func render(w io.Writer, s summary) error {
 	return nil
 }
 
+// operational reports whether every component shown on the status page is
+// operational.
+func operational(s summary) bool {
+	for _, component := range s.Components {
+		if component.Showcase && component.Status != "operational" {
+			return false
+		}
+	}
+	return true
+}
+
 // statusColor returns the color used to display a component status.
 func statusColor(status string) *color.Color {
 	switch status {

github_status_test.go

@@ -117,3 +117,25 @@ func TestStatusColor(t *testing.T) {
 		}
 	}
 }
+
+func TestOperational(t *testing.T) {
+	s, err := fetch(serveFixture(t).URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if operational(s) {
+		t.Error("fixture has an outage, want operational false")
+	}
+
+	for i := range s.Components {
+		s.Components[i].Status = "operational"
+	}
+	if !operational(s) {
+		t.Error("all components operational, want operational true")
+	}
+
+	s.Components[2].Status = "major_outage" // the non-showcase filler row
+	if !operational(s) {
+		t.Error("only a non-showcase component is down, want operational true")
+	}
+}