[golang] bootstrapped a client in yet another language

golang/pkg/api/client.go

@@ -0,0 +1,75 @@
+package api
+
+import (
+	"container/heap"
+	"context"
+	"net/http"
+	"time"
+)
+
+type Client struct {
+	baseURL    string
+	channel    chan *Request
+	ctx        context.Context
+	headers    *http.Header
+	httpClient *http.Client
+	pq         *PriorityQueue
+}
+
+func NewClient(ctx context.Context) *Client {
+	pq := make(PriorityQueue, 0)
+	heap.Init(&pq)
+	client := &Client{
+		baseURL: "https://api.spacetraders.io/v2",
+		channel: make(chan *Request),
+		ctx:     ctx,
+		headers: &http.Header{
+			"Content-Type": {"application/json"},
+		},
+		httpClient: &http.Client{
+			Timeout: time.Minute,
+		},
+		pq: &pq,
+	}
+	go queueProcessor(client)
+	return client
+}
+
+func (c *Client) Close() {
+	close(c.channel)
+}
+
+func (c *Client) SetToken(token string) {
+	c.headers.Set("Authorization", "Bearer "+token)
+}
+
+func queueProcessor(client *Client) {
+	var ok bool
+	for {
+		// The queue is empty so we do this blocking call
+		req := <-client.channel
+		heap.Push(client.pq, req)
+		// we enqueue all values read from the channel and process the queue's
+		// contents until empty. We keep reading the channel as long as this
+		// emptying goes on
+		for {
+			select {
+			case req = <-client.channel:
+				heap.Push(client.pq, req)
+			default:
+				if client.pq.Len() == 0 {
+					break
+				}
+				// we process one
+				if req, ok = heap.Pop(client.pq).(*Request); !ok {
+					panic("queueProcessor got something other than a Request on its channel")
+				}
+				response, err := client.sendOne(req.method, req.path, req.payload)
+				req.resp <- &Response{
+					Response: response,
+					Err:      err,
+				}
+			}
+		}
+	}
+}