From 52a626d7b9ee69b70ae48bbd4ef513d7c32a2172 Mon Sep 17 00:00:00 2001
From: Benjamin Congdon <bencongdon96@gmail.com>
Date: Fri, 27 Nov 2020 08:37:55 -0800
Subject: [PATCH] Add support for setting a global default User-Agent

---
 config/options.go          |  9 +++++++++
 config/parser.go           |  2 ++
 http/client/client.go      |  6 +++++-
 http/client/client_test.go | 25 ++++++++++++++++++++++++-
 4 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/config/options.go b/config/options.go
index f7d7bda0..b266a470 100644
--- a/config/options.go
+++ b/config/options.go
@@ -59,6 +59,7 @@ const (
 	defaultMetricsCollector                   = false
 	defaultMetricsRefreshInterval             = 60
 	defaultMetricsAllowedNetworks             = "127.0.0.1/8"
+	defaultUserAgent                          = ""
 )
 
 // Options contains configuration options.
@@ -112,6 +113,7 @@ type Options struct {
 	metricsCollector                   bool
 	metricsRefreshInterval             int
 	metricsAllowedNetworks             []string
+	userAgent                          string
 }
 
 // NewOptions returns Options with default values.
@@ -164,6 +166,7 @@ func NewOptions() *Options {
 		metricsCollector:                   defaultMetricsCollector,
 		metricsRefreshInterval:             defaultMetricsRefreshInterval,
 		metricsAllowedNetworks:             []string{defaultMetricsAllowedNetworks},
+		userAgent:                          defaultUserAgent,
 	}
 }
 
@@ -422,6 +425,11 @@ func (o *Options) MetricsAllowedNetworks() []string {
 	return o.metricsAllowedNetworks
 }
 
+// UserAgent returns the global User-Agent header for miniflux.
+func (o *Options) UserAgent() string {
+	return o.userAgent
+}
+
 func (o *Options) String() string {
 	var builder strings.Builder
 	builder.WriteString(fmt.Sprintf("LOG_DATE_TIME: %v\n", o.logDateTime))
@@ -473,5 +481,6 @@ func (o *Options) String() string {
 	builder.WriteString(fmt.Sprintf("METRICS_COLLECTOR: %v\n", o.metricsCollector))
 	builder.WriteString(fmt.Sprintf("METRICS_REFRESH_INTERVAL: %v\n", o.metricsRefreshInterval))
 	builder.WriteString(fmt.Sprintf("METRICS_ALLOWED_NETWORKS: %v\n", o.metricsAllowedNetworks))
+	builder.WriteString(fmt.Sprintf("USER_AGENT: %v\n", o.userAgent))
 	return builder.String()
 }
diff --git a/config/parser.go b/config/parser.go
index 0f4f40d4..45fd08a7 100644
--- a/config/parser.go
+++ b/config/parser.go
@@ -184,6 +184,8 @@ func (p *Parser) parseLines(lines []string) (err error) {
 			p.opts.metricsRefreshInterval = parseInt(value, defaultMetricsRefreshInterval)
 		case "METRICS_ALLOWED_NETWORKS":
 			p.opts.metricsAllowedNetworks = parseStringList(value, []string{defaultMetricsAllowedNetworks})
+		case "USER_AGENT":
+			p.opts.userAgent = parseString(value, defaultUserAgent)
 		}
 	}
 
diff --git a/http/client/client.go b/http/client/client.go
index adbfc369..cc137a59 100644
--- a/http/client/client.go
+++ b/http/client/client.go
@@ -72,9 +72,13 @@ func New(url string) *Client {
 
 // NewClientWithConfig initializes a new HTTP client with application config options.
 func NewClientWithConfig(url string, opts *config.Options) *Client {
+	userAgent := opts.UserAgent()
+	if userAgent == "" {
+		userAgent = DefaultUserAgent
+	}
 	return &Client{
 		inputURL:          url,
-		requestUserAgent:  DefaultUserAgent,
+		requestUserAgent:  userAgent,
 		ClientTimeout:     opts.HTTPClientTimeout(),
 		ClientMaxBodySize: opts.HTTPClientMaxBodySize(),
 		ClientProxyURL:    opts.HTTPClientProxy(),
diff --git a/http/client/client_test.go b/http/client/client_test.go
index fb66d1ec..74d67199 100644
--- a/http/client/client_test.go
+++ b/http/client/client_test.go
@@ -4,7 +4,12 @@
 
 package client // import "miniflux.app/http/client"
 
-import "testing"
+import (
+	"os"
+	"testing"
+
+	"miniflux.app/config"
+)
 
 func TestClientWithDelay(t *testing.T) {
 	clt := New("http://httpbin.org/delay/5")
@@ -49,3 +54,21 @@ func TestClientWithBasicAuth(t *testing.T) {
 		t.Fatalf(`The client should be authenticated successfully: %v`, err)
 	}
 }
+
+func TestClientRequestUserAgent(t *testing.T) {
+	clt := New("http://httpbin.org")
+	if clt.requestUserAgent != DefaultUserAgent {
+		t.Errorf(`The client had default User-Agent %q, wanted %q`, clt.requestUserAgent, DefaultUserAgent)
+	}
+
+	userAgent := "Custom User Agent"
+	os.Setenv("USER_AGENT", userAgent)
+	opts, err := config.NewParser().ParseEnvironmentVariables()
+	if err != nil {
+		t.Fatalf(`Parsing config failed: %v`, err)
+	}
+	clt = NewClientWithConfig("http://httpbin.org", opts)
+	if clt.requestUserAgent != userAgent {
+		t.Errorf(`The client had User-Agent %q, wanted %q`, clt.requestUserAgent, userAgent)
+	}
+}