From 622dd03bff5a56edc85b029aeb8846778856ce12 Mon Sep 17 00:00:00 2001
From: Minhaz Ahmed Syrus <msyrus@gmail.com>
Date: Sat, 27 Oct 2018 18:32:35 +0600
Subject: [PATCH] Initial commit

---
 .gitignore            |   3 ++
 README.md             |   3 ++
 cmd/req-check/main.go | 102 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 108 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 README.md
 create mode 100644 cmd/req-check/main.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e1ff94f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.vscode
+.DS_Store
+build
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..640ccab
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+# req-check
+
+This is a basic go http server for checking and dumping incoming requests
diff --git a/cmd/req-check/main.go b/cmd/req-check/main.go
new file mode 100644
index 0000000..766cfe3
--- /dev/null
+++ b/cmd/req-check/main.go
@@ -0,0 +1,102 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"io"
+	"mime"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// MiB is 1 mega byte
+const MiB = 1 << (10 * 2)
+
+var (
+	port, bcap int
+)
+
+func main() {
+	flag.IntVar(&port, "port", 8080, "server port")
+	flag.IntVar(&bcap, "cap", 512, "max request body bytes in response")
+	flag.Parse()
+
+	http.ListenAndServe(":"+strconv.Itoa(port), http.HandlerFunc(HandleReq))
+}
+
+// HandleReq serves req info
+func HandleReq(w http.ResponseWriter, r *http.Request) {
+	resp := map[string]interface{}{}
+	resp["time"] = time.Now().UTC().Format(time.RFC3339Nano)
+	resp["method"] = r.Method
+	resp["uri"] = r.Host + r.RequestURI
+	resp["query"] = r.URL.Query()
+	resp["headers"] = r.Header
+	resp["remote_addr"] = r.RemoteAddr
+
+	defer r.Body.Close()
+	body, cpd, err := parseBody(r)
+	if err != nil {
+		resp["body_error"] = err.Error()
+	}
+	resp["body_capped"] = cpd
+	resp["body"] = body
+	if body != nil {
+		if data, ok := body.([]byte); ok {
+			typ := http.DetectContentType(data)
+			if strings.HasPrefix(typ, "text/") {
+				resp["body"] = string(data)
+			}
+			resp["body_context_type"] = typ
+		}
+	}
+
+	w.Header().Set("Content-Type", mime.TypeByExtension(".json"))
+	w.WriteHeader(200)
+
+	json.NewEncoder(w).Encode(resp)
+}
+
+func parseBody(r *http.Request) (interface{}, bool, error) {
+	typ, _, err := mime.ParseMediaType(r.Header.Get("Content-Type"))
+	if err != nil {
+		return nil, false, err
+	}
+
+	switch typ {
+	case "application/json":
+		body := map[string]interface{}{}
+		if err = json.NewDecoder(r.Body).Decode(body); err != nil {
+			return nil, false, err
+		}
+
+	case "application/x-www-form-urlencoded":
+		if err = r.ParseForm(); err != nil {
+			return nil, false, err
+		}
+		return r.PostForm, false, nil
+
+	case "multipart/form-data":
+		if err = r.ParseMultipartForm(2 * MiB); err != nil {
+			return nil, false, err
+		}
+		return r.MultipartForm, false, nil
+	}
+
+	body := make([]byte, bcap+1)
+	capped := false
+	n, err := r.Body.Read(body)
+	if err != nil && err != io.EOF {
+		return nil, false, err
+	}
+	body = body[:n]
+
+	if len(body) > bcap {
+		capped = true
+		body = body[:bcap]
+	}
+
+	return body, capped, nil
+}