From 976999bba761689cd4af188c85c60be907d8b65d Mon Sep 17 00:00:00 2001
From: Derek Tamsen <dtamsen@gmail.com>
Date: Tue, 21 Feb 2017 23:51:02 -0800
Subject: [PATCH] #2 use viper to read config file and env vars

---
 .gitignore    |  1 +
 README.md     |  4 ++--
 aws/awsurl.go | 10 +++++++---
 main.go       | 29 +++++++++++++++++++++--------
 4 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/.gitignore b/.gitignore
index befcc8e..e08647a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 awss3urlsigner
+config.yaml
diff --git a/README.md b/README.md
index 51d3870..5a61140 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ This service runs as a http server to receive requests, sign urls, and redirect
 ## Design
 
 ```
-user -> nginx (auth + proxy) -> aws-s3-url-signer (url signing + redirect) -> user (redirected) -> S3/cloudfront
+user -> nginx (auth + proxy) -> awss3urlsigner (url signing + redirect) -> user (redirected) -> S3/cloudfront
 ```
 
 1. `user`
@@ -16,7 +16,7 @@ user -> nginx (auth + proxy) -> aws-s3-url-signer (url signing + redirect) -> us
 2. `nginx`
     1. Authenticates the user with client PKI certificates or another form of authentication.
     2. Proxies the traffic to this service.
-3. `aws-s3-url-signer`
+3. `awss3urlsigner`
     1. Takes the requested url from the user and signs it using the aws sdk
     2. Redirects user to the S3 or cloudfront endpoint with a signed url
 4. `user`
diff --git a/aws/awsurl.go b/aws/awsurl.go
index 4737c33..25bd646 100644
--- a/aws/awsurl.go
+++ b/aws/awsurl.go
@@ -1,14 +1,18 @@
 package awsurl
 
 import (
+	"log"
+	"time"
+
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/s3"
-	"log"
-	"time"
 )
 
-func PreSign(obj string) string{
+// S3PreSign presigns the url for s3 GET allowing for signed downloads of an s3 asset.
+// The  obj to be signed is sent as a string.
+// Returns the signed url as a string.
+func S3PreSign(obj string) string {
 	sess, err := session.NewSession()
 	if err != nil {
 		panic(err)
diff --git a/main.go b/main.go
index 84145ca..8ff7a3d 100644
--- a/main.go
+++ b/main.go
@@ -1,24 +1,37 @@
 package main
 
 import (
-	"github.com/derektamsen/awss3urlsigner/aws"
+	"fmt"
 	"log"
 	"net/http"
 	"time"
+
+	"github.com/derektamsen/awss3urlsigner/aws"
+	"github.com/spf13/viper"
 )
 
-func handler(w http.ResponseWriter, r *http.Request) {
-	presigned_url := awsurl.PreSign(r.URL.Path[1:])
-	http.Redirect(w, r, presigned_url, http.StatusFound)
+func getConfig() {
+	viper.SetConfigName("config")
+	viper.AddConfigPath(".")
+	err := viper.ReadInConfig()
+	if err != nil {
+		panic(fmt.Errorf("Fatal error config file: %s", err))
+	}
+}
+
+func httphandler(w http.ResponseWriter, r *http.Request) {
+	presignedURL := awsurl.S3PreSign(r.URL.Path[1:])
+	http.Redirect(w, r, presignedURL, http.StatusFound)
 }
 
 func main() {
-	httpserver := &http.Server{
-		Addr:           ":8080",
+	getConfig()
+	httpServer := &http.Server{
+		Addr:           ":" + viper.GetString("http_port"),
 		ReadTimeout:    10 * time.Second,
 		WriteTimeout:   10 * time.Second,
 		MaxHeaderBytes: 1 << 20,
 	}
-	http.HandleFunc("/", handler)
-	log.Fatal(httpserver.ListenAndServe())
+	http.HandleFunc("/", httphandler)
+	log.Fatal(httpServer.ListenAndServe())
 }