Moved http related functions to their own file; added 'sum.go' for a second endpoint.

README.md

@@ -1,3 +1,7 @@
-# Fibnacci
+# Fibonacci
 
-Just a little proof-of-concept setup to help teach myself Go, Containerisation, and CI/CD.
+Just a little proof-of-concept setup to help teach myself Go, Containerisation, and CI/CD.
+
+The Go code itself is basically a HTTP listener that listens to a port (argv[1], defaulting to 8088 if not specified), and handles POST requests to /fibonacci by responding with the fibonacci number of the indicated sequence. 
+
+I've added a second handler /sum to it as another part of my experiments.

functions/fibonacci.go

@@ -1,16 +1,5 @@
 package functions
 
-import (
-	"fmt"
-	"net/http"
-	"strconv"
-)
-
-func HttpAbort(w http.ResponseWriter, code int, message string) {
-	w.WriteHeader(code)
-	fmt.Fprint(w, message)
-}
-
 func MyFibonacci(count int) (fibonaccivalue int) {
 	fibonaccivalue = 1
 	var prev_fibonacci int = 0
@@ -21,37 +10,3 @@ func MyFibonacci(count int) (fibonaccivalue int) {
 	}
 	return
 }
-
-func HttFibonacci(w http.ResponseWriter, request *http.Request) {
-	switch request.Method {
-	case "POST":
-		error := request.ParseForm()
-		if error != nil {
-			fmt.Printf("Error parsing POST request: %s\n", error)
-			HttpAbort(w, http.StatusUnprocessableEntity,
-				"Unable to parse your POST request.\n")
-		} else {
-			s_seq := request.Form.Get("seq")
-			seq, error := strconv.Atoi(s_seq)
-			if error != nil {
-				fmt.Printf("Error parsing integer value out of %s: %s\n",
-					s_seq,
-					error)
-				HttpAbort(w, http.StatusExpectationFailed,
-					fmt.Sprintf("[%s] is not a number.\n", s_seq))
-			} else if seq < 1 {
-				fmt.Printf("Invalid sequence number: %d\n", seq)
-				HttpAbort(w, http.StatusBadRequest,
-					"Please provide a positive integer as the sequence number.\n")
-			} else {
-				fmt.Printf("Received request for Fibonacci Sequence Number %d\n",
-					seq)
-				fmt.Fprintf(w, "Fibonacci sequence index [%d]: %d\n",
-					seq, MyFibonacci(seq))
-			}
-		}
-	default:
-		HttpAbort(w, http.StatusMethodNotAllowed,
-			fmt.Sprintf("Operation %s not implemented for this URL", request.Method))
-	}
-}

functions/http.go

@@ -0,0 +1,74 @@
+package functions
+
+// HTTP helper functions doing the input checking and calling the actual math functions
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+)
+
+func HttpAbort(w http.ResponseWriter, code int, message string) {
+	w.WriteHeader(code)
+	fmt.Fprint(w, message)
+}
+
+func HttpGetPostInt(request *http.Request, key string) (value int, error error) {
+	switch request.Method {
+	case "POST":
+		error = request.ParseForm()
+		if error != nil {
+			error = fmt.Errorf("Unable to parse HTTP POST input: %s",
+				error.Error())
+			return
+		}
+		value, error = strconv.Atoi(request.Form.Get(key))
+		if error != nil {
+			fmt.Printf("Error parsing parameter '%s'\n", key)
+			error = fmt.Errorf("Unable to parse parameter '%s' as an integer: %s",
+				key, error.Error())
+		}
+		return
+	default:
+		error = fmt.Errorf("This endpoint does not support %s operations.\n", request.Method)
+		return
+	}
+}
+
+func HttFibonacci(w http.ResponseWriter, request *http.Request) {
+	seq, error := HttpGetPostInt(request, "seq")
+	if error != nil {
+		HttpAbort(w, http.StatusBadRequest,
+			fmt.Sprintf("Could not get parameter: %s", error.Error()))
+	} else if seq < 1 {
+		HttpAbort(w, http.StatusBadRequest,
+			"Please provide a positive integer as the sequence number.\n")
+	} else {
+		fmt.Printf("Received request for Fibonacci Sequence Number %d\n",
+			seq)
+		fmt.Fprintf(w, "Fibonacci sequence index [%d]: %d\n",
+			seq, MyFibonacci(seq))
+	}
+	return
+}
+
+func HttSum(w http.ResponseWriter, request *http.Request) {
+	var errorstr string
+	first, error := HttpGetPostInt(request, "first")
+	if error != nil {
+		errorstr = error.Error()
+	}
+	second, error := HttpGetPostInt(request, "second")
+	if error != nil {
+		errorstr = error.Error()
+	}
+
+	if errorstr != "" {
+		HttpAbort(w, http.StatusBadRequest,
+			fmt.Sprintf("Invalid input: %s\n", errorstr))
+		return
+	}
+	fmt.Printf("Received a request to add %d and %d.\n", first, second)
+	fmt.Fprintf(w, "The sum of %d and %d is %d.\n", first, second, sum(first, second))
+
+}

functions/sum.go

@@ -0,0 +1,6 @@
+package functions
+
+func sum(first int, second int) (result int) {
+	result = first + second
+	return
+}

main.go

@@ -9,17 +9,6 @@ import (
 	"darjeeling.systemec.nl/rhouben/fibonacci/functions"
 )
 
-func MyFibonacci(count int) (fibonaccivalue int) {
-	fibonaccivalue = 1
-	var prev_fibonacci int = 0
-
-	for i := 1; i < count; i++ {
-		fibonaccivalue += prev_fibonacci
-		prev_fibonacci = fibonaccivalue - prev_fibonacci
-	}
-	return
-}
-
 func main() {
 	var port_number int
 	var error error
@@ -40,6 +29,7 @@ func main() {
 	}
 	bind_socket = fmt.Sprintf(":%d", port_number)
 	http.HandleFunc("/fibonacci", functions.HttFibonacci)
-	fmt.Printf("Listening on port %d...", port_number)
+	http.HandleFunc("/sum", functions.HttSum)
+	fmt.Printf("Listening on port %d...\n", port_number)
 	http.ListenAndServe(bind_socket, nil)
 }