Remove ansible dependencies

README.md

@@ -23,41 +23,13 @@ groups:
 
 Only alert rules are altered, recording rules are left intact and are just passed to output without change.
 
-## Ansible
 
+Running the program
 ```
-- name: Override default rules
-  become: false
-  delegate_to: localhost
-  prometheus_merge:
-    rulesPath: "/tmp/alerting_rules"
-  register: override
-
-- name: Copy rules to files
-  become: false
-  delegate_to: localhost
-  copy:
-    content: "{{ override.alerts }}"
-    dest: "/tmp/processed_rules.rules"
-```
-
-## Dev/Testing
-
-The application expects JSON file as it's input.
-
-config.json
-```
-{
-  "rulesPath": "./rules"
-}
-```
-
-```
-go run main.go config.json
+./prometheus_merget <path_to_rules>
 ```
 
 ## Build
-
 ```
 CGO_ENABLED=0 GOOS=linux go build -o prometheus_alert_overrider main.go
 ```

main.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"log"
@@ -12,17 +11,6 @@ import (
 	"gopkg.in/yaml.v2"
 )
 
-type ModuleArgs struct {
-	RulesPath string
-}
-
-type Response struct {
-	Msg     string `json:"msg"`
-	Alerts  string `json:"alerts"`
-	Changed bool   `json:"changed"`
-	Failed  bool   `json:"failed"`
-}
-
 type AlertFile struct {
 	Groups []Group `yaml:"groups,omitempty"`
 }
@@ -87,15 +75,6 @@ func (alertFile AlertFile) Override(overrideRule Rule) {
 	}
 }
 
-func ExitJson(responseBody Response) {
-	returnResponse(responseBody)
-}
-
-func failJson(responseBody Response) {
-	responseBody.Failed = true
-	returnResponse(responseBody)
-}
-
 func LoadRules(input []byte) (*AlertFile, error) {
 	var alertRules AlertFile
 	err := yaml.Unmarshal(input, &alertRules)
@@ -111,21 +90,6 @@ func containsOperator(needle string, haystack string) bool {
 	return result
 }
 
-func returnResponse(responseBody Response) {
-	var response []byte
-	var err error
-	response, err = json.Marshal(responseBody)
-	if err != nil {
-		response, _ = json.Marshal(Response{Msg: "Invalid response object"})
-	}
-	fmt.Println(string(response))
-	if responseBody.Failed {
-		os.Exit(1)
-	} else {
-		os.Exit(0)
-	}
-}
-
 func extractFilterExpressions(input string) string {
 	re := regexp.MustCompile("{.*}")
 	return re.FindAllString(input, 1)[0]
@@ -175,7 +139,7 @@ func NegateFilterExpression(input string) string {
 	return strings.Join(exprFilterBodyElements[:], ",")
 }
 
-func getFilePaths(rootPath string, response Response) []string {
+func getFilePaths(rootPath string) []string {
 	var filePaths []string
 
 	files, err := ioutil.ReadDir(rootPath)
@@ -189,11 +153,10 @@ func getFilePaths(rootPath string, response Response) []string {
 	return filePaths
 }
 
-func loadAlertFile(filePath string, response Response) *AlertFile {
+func loadAlertFile(filePath string) *AlertFile {
 	input, err := ioutil.ReadFile(filePath)
 	if err != nil {
-		response.Msg = "Failed to read file " + filePath
-		failJson(response)
+		fmt.Errorf("Failed to read file " + filePath)
 		return nil
 	}
 	alertFile, err := LoadRules(input)
@@ -204,34 +167,18 @@ func loadAlertFile(filePath string, response Response) *AlertFile {
 }
 
 func main() {
-	var response Response
 
 	if len(os.Args) != 2 {
-		response.Msg = "No argument file provided"
-		failJson(response)
-	}
-
-	argsFile := os.Args[1]
-
-	text, err := ioutil.ReadFile(argsFile)
-	if err != nil {
-		response.Msg = "Could not read configuration file: " + argsFile
-		failJson(response)
-	}
-
-	var moduleArgs ModuleArgs
-	err = json.Unmarshal(text, &moduleArgs)
-	if err != nil {
-		response.Msg = "Configuration file not valid JSON: " + argsFile
-		failJson(response)
+		panic("No arguments provided")
 	}
 
-	files := getFilePaths(moduleArgs.RulesPath, response)
+	filePaths := os.Args[1]
+	files := getFilePaths(filePaths)
 
 	var alertFiles []AlertFile
 
 	for _, file := range files {
-		alertFile := loadAlertFile(file, response)
+		alertFile := loadAlertFile(file)
 		if alertFile != nil {
 			alertFiles = append(alertFiles, *alertFile)
 		}
@@ -250,7 +197,5 @@ func main() {
 		}
 	}
 
-	response.Msg = "done"
-	response.Alerts = alertFile.Exporter()
-	ExitJson(response)
+	fmt.Print(alertFile.Exporter())
 }