chore: update readme

README.md

@@ -2,9 +2,8 @@
 [VMaaS](https://github.com/RedHatInsights/vmaas) library for Updates and Vulnerabilities evaluation
 
 # Prerequisites
-sqlite data dump generated by [vmaas-reposcan](https://github.com/RedHatInsights/vmaas/tree/master/vmaas/reposcan) `/api/vmaas/v1/export/dump`
-
-available in [examples/vmaas.db](https://github.com/RedHatInsights/vmaas-lib/blob/main/example/vmaas.db) for testing purposes
+- [rpm](https://rpm.org/) library
+- sqlite data dump generated by [vmaas-reposcan](https://github.com/RedHatInsights/vmaas/tree/master/vmaas/reposcan) `/api/vmaas/v1/export/dump`. Available in [example/vmaas.db](https://github.com/RedHatInsights/vmaas-lib/blob/main/example/vmaas.db) for testing purposes
 
 # Usage
 ```go
@@ -29,9 +28,24 @@ request := vmaas.Request{
 	Packages: []string{"kernel-0:4.18.0-372.26.1.el8_6.x86_64"},
 }
 // get CVEs for given package
-vulnerabilities, _ := api.Vulnerabilities(request)
+vulnerabilities, _ := api.Vulnerabilities(&request)
 // get Updates for given package
-updates, _ := api.Updates(request)
+updates, _ := api.Updates(&request)
+
+```
 
+or inspect and run [example/main.go](https://github.com/RedHatInsights/vmaas-lib/blob/main/example/main.go)
+```
+go run example/main.go
 ```
 
+# Setup for MacOS
+This package uses `rpm` library, it can be installed using [Homebrew](https://brew.sh/)
+```
+brew install rpm
+``` 
+and linked with
+```
+export CGO_LDFLAGS="-L/opt/homebrew/opt/rpm/lib"
+export CGO_CFLAGS="-I/opt/homebrew/opt/rpm/include -I/opt/homebrew/opt/popt/include"
+```

example/main.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"github.com/redhatinsights/vmaas-lib/vmaas"
+	"github.com/redhatinsights/vmaas-lib/vmaas/utils"
+)
+
+func main() {
+	api, _ := vmaas.InitFromFile("./example/vmaas.db")
+	repo := []string{"rhel-7-server-rpms"}
+	request := vmaas.Request{
+		Packages: []string{"kernel-0:3.10.0-957.5.1.el7.x86_64"},
+		Repos:    &repo,
+		UseCsaf:  true,
+	}
+
+	vulnerabilities, _ := api.Vulnerabilities(&request)
+	utils.LogInfo("cves", vulnerabilities.CVEs, "Vulnerabilities")
+	utils.LogInfo("manually fixable cves", vulnerabilities.ManuallyFixableCVEs, "Vulnerabilities")
+	utils.LogInfo("unpatched cves", vulnerabilities.UnpatchedCVEs, "Vulnerabilities")
+}