functions: hot containers (#332)

* functions: modify datastore to accomodate hot containers support

* functions: protocol between functions and hot containers

* functions: add hot containers clockwork

* fn: add hot containers support

examples/hotcontainers/http/func.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"strconv"
+)
+
+func main() {
+	for {
+		res := http.Response{
+			Proto:      "HTTP/1.1",
+			ProtoMajor: 1,
+			ProtoMinor: 1,
+			StatusCode: 200,
+			Status:     "OK",
+		}
+
+		r := bufio.NewReader(os.Stdin)
+		req, err := http.ReadRequest(r)
+
+		var buf bytes.Buffer
+		if err != nil {
+			res.StatusCode = 500
+			res.Status = http.StatusText(res.StatusCode)
+			fmt.Fprintln(&buf, err)
+		} else {
+			l, _ := strconv.Atoi(req.Header.Get("Content-Length"))
+			p := make([]byte, l)
+			r.Read(p)
+			fmt.Fprintf(&buf, "Hello %s\n", p)
+			for k, vs := range req.Header {
+				fmt.Fprintf(&buf, "ENV: %s %#v\n", k, vs)
+			}
+		}
+
+		res.Body = ioutil.NopCloser(&buf)
+		res.ContentLength = int64(buf.Len())
+		res.Write(os.Stdout)
+	}
+}

examples/hotcontainers/http/hotroute.json

@@ -0,0 +1,9 @@
+{"route":{
+  "app_name": "myapp",
+  "path": "/hot",
+  "image": "USERNAME/hchttp",
+  "memory": 64,
+  "type": "sync",
+  "config": null,
+  "format": "http"
+}}