Initial Refactor (#1234)

* Inital Refactor

Removing the repeated logic exposed some problems with the reponse
writers.

Currently, the trigger writer was overlaid on part of the header
writing. The main invoke blog writing into the different levels of the
overlays at different points in the logic.

Instead, by extending the types and embedded structs, the writer is
more transparent. So, at the end of the flow it goes over all the
headers available and removes our prefixes. This lets the invoke logic
just write to the top level.

Going to continue after lunch to try and remove some of the layers and
param passing.

* Try and repeat concurrency failure

* Nested FromHTTPFnRequest inside FromHTTPTriggerRequest

* Consolidate buffer pooling logic

* go fmt yourself

* fix import

api/agent/call.go

@@ -67,7 +67,6 @@ var skipTriggerHeaders = map[string]bool{
 // Sets up a call from an http trigger request
 func FromHTTPTriggerRequest(app *models.App, fn *models.Fn, trigger *models.Trigger, req *http.Request) CallOpt {
 	return func(c *call) error {
-		contentType := req.Header.Get("Content-Type")
 		// transpose trigger headers into HTTP
 		headers := make(http.Header)
 		for k, vs := range req.Header {
@@ -84,61 +83,13 @@ func FromHTTPTriggerRequest(app *models.App, fn *models.Fn, trigger *models.Trig
 		requestUrl := reqURL(req)
 
 		headers.Set("Fn-Http-Method", req.Method)
-		if contentType != "" {
-			headers.Set("Content-Type", contentType)
-		}
 		headers.Set("Fn-Http-Request-Url", requestUrl)
 		headers.Set("Fn-Intent", "httprequest")
 		req.Header = headers
 
-		if fn.Format == "" {
-			fn.Format = models.FormatDefault
-		}
-
-		id := id.New().String()
-
-		// TODO this relies on ordering of opts, but tests make sure it works, probably re-plumb/destroy headers
-		// TODO async should probably supply an http.ResponseWriter that records the logs, to attach response headers to
-		if rw, ok := c.w.(http.ResponseWriter); ok {
-			// TODO deprecate after CLI is updated
-			rw.Header().Add("Fn-Call-ID", id)
-			rw.Header().Add("FN_CALL_ID", id)
-		}
-
-		var syslogURL string
-		if app.SyslogURL != nil {
-			syslogURL = *app.SyslogURL
-		}
-
-		c.Call = &models.Call{
-			ID:    id,
-			Image: fn.Image,
-			// Delay: 0,
-			Type:   "sync",
-			Format: fn.Format,
-			// Payload: TODO,
-			Priority:    new(int32), // TODO this is crucial, apparently
-			Timeout:     fn.Timeout,
-			IdleTimeout: fn.IdleTimeout,
-			TmpFsSize:   0, // TODO clean up this
-			Memory:      fn.Memory,
-			CPUs:        0, // TODO clean up this
-			Config:      buildConfig(app, fn, trigger.Source),
-			// TODO - this wasn't really the intention here (that annotations would naturally cascade
-			// but seems to be necessary for some runner behaviour
-			Annotations: app.Annotations.MergeChange(fn.Annotations).MergeChange(trigger.Annotations),
-			Headers:     req.Header,
-			CreatedAt:   common.DateTime(time.Now()),
-			URL:         requestUrl,
-			Method:      req.Method,
-			AppID:       app.ID,
-			AppName:     app.Name,
-			FnID:        fn.ID,
-			TriggerID:   trigger.ID,
-			SyslogURL:   syslogURL,
-		}
-		c.req = req
-		return nil
+		err := FromHTTPFnRequest(app, fn, req)(c)
+		c.Model().TriggerID = trigger.ID
+		return err
 	}
 }