feat(cmd): add support for cmd (#11)

Makefile

@@ -18,9 +18,11 @@ format: ## Format code
 
 test: ## Run tests
 	go test -test.timeout 120s -count=1 .
+	go test -test.timeout 120s -count=1 ./ciinfo/
 
 test-verbose: ## Run tests with verbose output
 	go test -test.timeout 120s -v -cover -count=1 .
+	go test -test.timeout 120s -v -cover -count=1 ./ciinfo/
 
 compile-constants: ## Generates 'constants.go' containing the list with constant values
 	cp vendors.go compile-constants

README.md

@@ -36,6 +36,33 @@ if ciinfo.IsCI {
 }
 ```
 
+## CLI Support
+
+`ciinfo` can also be used as a CLI. You can install it with
+
+```sh
+go install github.com/gkampitakis/ciinfo/ciinfo
+```
+
+Then `ciinfo` command will be successful ( code 0 ) if running on CI else error ( code -1 ).
+
+
+```sh
+#  will output isCI if running onCI
+ciinfo && echo 'isCI'
+```
+
+`ciinfo` also has
+
+```shell
+Usage of ciinfo:
+  -output string
+    	you can output info [json, pretty].
+  -pr
+    	check if shell is running on CI for a Pull Request.
+```
+
+
 ## Supported CI tools
 
 Officially supported CI servers:

ciinfo/main.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/gkampitakis/ciinfo"
+)
+
+const (
+	YES = 0
+	NO  = -1
+)
+
+func main() {
+	isPr := flag.Bool("pr", false, "check if shell is running on CI for a Pull Request.")
+	output := flag.String("output", "", "you can output info [json, pretty].")
+
+	flag.Parse()
+
+	run(os.Exit, os.Stdout, *isPr, *output)
+}
+
+func run(exit func(int), w io.Writer, isPR bool, output string) {
+	result := NO
+
+	if isPR {
+		if ciinfo.IsPr {
+			result = YES
+		}
+
+		exit(result)
+	}
+
+	if output == "json" {
+		jsonPrint(w)
+		return
+	}
+
+	if output == "pretty" {
+		prettyPrint(w)
+		return
+	}
+
+	if ciinfo.IsCI {
+		result = YES
+	}
+
+	exit(result)
+}
+
+func jsonPrint(w io.Writer) {
+	fmt.Fprintf(w, `{
+	"is_ci": %t,
+	"ci_name": "%s",
+	"pull_request": %t
+}
+`, ciinfo.IsCI, ciinfo.Name, ciinfo.IsPr)
+}
+
+func prettyPrint(w io.Writer) {
+	if !ciinfo.IsCI {
+		fmt.Fprintln(w, "Not running on CI.")
+		return
+	}
+
+	if ciinfo.Name != "" {
+		fmt.Fprintf(w, "CI Name: %s\n", ciinfo.Name)
+	} else {
+		fmt.Fprintln(w, "Running on CI.")
+	}
+
+	if ciinfo.IsPr {
+		fmt.Fprintln(w, "Is Pull Request.")
+	}
+}

ciinfo/main_test.go

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"io"
+	"strings"
+	"testing"
+
+	"github.com/gkampitakis/ciinfo"
+)
+
+func mockExit(t *testing.T, expectedCode int) func(int) {
+	t.Helper()
+	return func(i int) {
+		if i != expectedCode {
+			t.Errorf("expected code: %d but got: %d\n", expectedCode, i)
+		}
+	}
+}
+
+type mockWriter struct {
+	mockWrite func([]byte)
+}
+
+func (m mockWriter) Write(p []byte) (int, error) {
+	m.mockWrite(p)
+	return 0, nil
+}
+
+func TestCMD(t *testing.T) {
+	t.Run("should be successful in case of pr", func(t *testing.T) {
+		ciinfo.IsPr = true
+
+		run(mockExit(t, 0), io.Discard, true, "")
+	})
+
+	t.Run("should exit with error in case not being a pr", func(t *testing.T) {
+		ciinfo.IsPr = false
+		ciinfo.IsCI = false
+
+		run(mockExit(t, -1), io.Discard, true, "")
+	})
+
+	t.Run("should print json output", func(t *testing.T) {
+		ciinfo.IsPr = true
+		ciinfo.Name = "mock-ci"
+		ciinfo.IsCI = true
+
+		m := mockWriter{
+			mockWrite: func(b []byte) {
+				// clean up tabs,spaces and newlines
+				chars := []string{" ", "\n", "\t"}
+				v := string(b)
+				for _, c := range chars {
+					v = strings.ReplaceAll(v, c, "")
+				}
+
+				if v != `{"is_ci":true,"ci_name":"mock-ci","pull_request":true}` {
+					t.Error("expected json format")
+				}
+			},
+		}
+
+		run(nil, m, false, "json")
+	})
+
+	t.Run("should print pretty output when not on ci", func(t *testing.T) {
+		ciinfo.IsCI = false
+
+		m := mockWriter{
+			mockWrite: func(b []byte) {
+				if string(b) != "Not running on CI.\n" {
+					t.Error("expected not running on CI.")
+				}
+			},
+		}
+
+		run(nil, m, false, "pretty")
+	})
+
+	t.Run("should print pretty output", func(t *testing.T) {
+		ciinfo.IsPr = true
+		ciinfo.Name = "mock-ci"
+		ciinfo.IsCI = true
+		msgs := []string{
+			"CI Name: mock-ci\n",
+			"Is Pull Request.\n",
+		}
+
+		m := mockWriter{
+			mockWrite: func(b []byte) {
+				msg := msgs[0]
+				msgs = msgs[1:]
+				if string(b) != msg {
+					t.Errorf("unexpected message: %s", string(b))
+				}
+			},
+		}
+
+		run(nil, m, false, "pretty")
+	})
+
+	t.Run("should print pretty output without name", func(t *testing.T) {
+		ciinfo.IsPr = true
+		ciinfo.Name = ""
+		ciinfo.IsCI = true
+		msgs := []string{
+			"Running on CI.\n",
+			"Is Pull Request.\n",
+		}
+
+		m := mockWriter{
+			mockWrite: func(b []byte) {
+				msg := msgs[0]
+				msgs = msgs[1:]
+				if string(b) != msg {
+					t.Errorf("unexpected message: %s", string(b))
+				}
+			},
+		}
+
+		run(nil, m, false, "pretty")
+	})
+
+	t.Run("should be successful code", func(t *testing.T) {
+		ciinfo.IsPr = true
+		ciinfo.Name = "mock-ci"
+		ciinfo.IsCI = true
+
+		run(mockExit(t, 0), io.Discard, false, "")
+	})
+
+	t.Run("should be error code", func(t *testing.T) {
+		ciinfo.IsCI = false
+
+		run(mockExit(t, -1), io.Discard, false, "")
+	})
+}