Add sanity checking for configuration.

2 files changed, 26 insertions, 0 deletions

diff --git a/networkQuality.go b/networkQuality.go
index ae8e25b..886022e 100644
--- a/networkQuality.go
+++ b/networkQuality.go
@@ -9,6 +9,7 @@ import (
 	"io/ioutil"
 	_ "log"
 	"net/http"
+	"net/url"
 	"os"
 	"time"
 
@@ -33,6 +34,19 @@ func (c *Config) String() string {
 	return fmt.Sprintf("Version: %d\nSmall URL: %s\nLarge URL: %s\nUpload URL: %s", c.Version, c.Urls.SmallUrl, c.Urls.LargeUrl, c.Urls.UploadUrl)
 }
 
+func (c *Config) IsValid() error {
+	if parsedUrl, err := url.ParseRequestURI(c.Urls.LargeUrl); err != nil || parsedUrl.Scheme != "https" {
+		return fmt.Errorf("Configuration url large_https_download_url is invalid: %s", utilities.Conditional(len(c.Urls.LargeUrl) != 0, c.Urls.LargeUrl, "Missing"))
+	}
+	if parsedUrl, err := url.ParseRequestURI(c.Urls.SmallUrl); err != nil || parsedUrl.Scheme != "https" {
+		return fmt.Errorf("Configuration url small_https_download_url is invalid: %s", utilities.Conditional(len(c.Urls.SmallUrl) != 0, c.Urls.SmallUrl, "Missing"))
+	}
+	if parsedUrl, err := url.ParseRequestURI(c.Urls.UploadUrl); err != nil || parsedUrl.Scheme != "https" {
+		return fmt.Errorf("Configuration url https_upload_url is invalid: %s", utilities.Conditional(len(c.Urls.UploadUrl) != 0, c.Urls.UploadUrl, "Missing"))
+	}
+	return nil
+}
+
 func toMBs(bytes float64) float64 {
 	return float64(bytes) / float64(1024*1024)
 }
@@ -171,6 +185,11 @@ func main() {
 
 	// TODO: Make sure that all configuration values are present and accounted for!
 
+	if err := config.IsValid(); err != nil {
+		fmt.Fprintf(os.Stderr, "Error: Invalid configuration returned from %s: %v\n", configUrl, err)
+		return
+	}
+
 	if *debug {
 		fmt.Printf("Configuration: %s\n", &config)
 	}
diff --git a/utilities/utilities.go b/utilities/utilities.go
index fd5c824..54f0f4a 100644
--- a/utilities/utilities.go
+++ b/utilities/utilities.go
@@ -8,3 +8,10 @@ func SignedPercentDifference(current float64, previous float64) (difference floa
 func AbsPercentDifference(current float64, previous float64) (difference float64) {
 	return (math.Abs(current-previous) / (float64(current+previous) / 2.0)) * float64(100)
 }
+
+func Conditional(condition bool, t string, f string) string {
+	if condition {
+		return t
+	}
+	return f
+}