luci-go: Basic support for event logging in Go.

common/eventlog/settings.go

Index: common/eventlog/settings.go
diff --git a/common/eventlog/settings.go b/common/eventlog/settings.go
new file mode 100644
index 0000000000000000000000000000000000000000..d73e4c6bf6685f385561f89d1f8437cca554fa75
--- /dev/null
+++ b/common/eventlog/settings.go
@@ -0,0 +1,32 @@
+// Copyright 2016 The LUCI Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+package eventlog
+
+import "net/http"
+
+// A ClientOption is an optional argument to NewClient.
+type ClientOption interface {
+	apply(*clientSettings)
+}
+
+type clientSettings struct {
+	HTTPClient *http.Client
+}
+
+func (cs *clientSettings) Populate(opts []ClientOption) {
+}
+
+type httpClientOption struct {
+	*http.Client
+}
+
+func (opt httpClientOption) apply(cs *clientSettings) {
+	cs.HTTPClient = opt.Client
+}
+
+// WithHTTPClient returns a ClientOption that specifies the HTTP client to use as the basis of communications.
+func WithHTTPClient(client *http.Client) ClientOption {
+	return httpClientOption{client}
+}