From ce788fcd88289f37f99bb434de9c67172f763a3e Mon Sep 17 00:00:00 2001
From: Vincent Batts <vbatts@hashbangbash.com>
Date: Thu, 26 Jan 2017 18:47:54 -0500
Subject: [PATCH] fetch: Fetch a ChangeLog from a Repo

and get its remote last-modified time

Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
---
 fetch/fetch.go      | 39 +++++++++++++++++++++++++++++++++++++++
 fetch/fetch_test.go | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+)
 create mode 100644 fetch/fetch.go
 create mode 100644 fetch/fetch_test.go

diff --git a/fetch/fetch.go b/fetch/fetch.go
new file mode 100644
index 0000000..6d7f54c
--- /dev/null
+++ b/fetch/fetch.go
@@ -0,0 +1,39 @@
+package fetch
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"../changelog"
+)
+
+type Repo struct {
+	URL string
+}
+
+func (r Repo) get(file string) (*http.Response, error) {
+	return http.Get(r.URL + "/" + file)
+}
+
+func (r Repo) ChangeLog() (e []changelog.Entry, mtime time.Time, err error) {
+	resp, err := r.get("ChangeLog.txt")
+	if err != nil {
+		return nil, time.Unix(0, 0), err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return nil, time.Unix(0, 0), fmt.Errorf("%d status from %s", resp.StatusCode, resp.Request.URL)
+	}
+
+	mtime, err = http.ParseTime(resp.Header.Get("last-modified"))
+	if err != nil {
+		return nil, time.Unix(0, 0), err
+	}
+
+	e, err = changelog.Parse(resp.Body)
+	if err != nil {
+		return nil, mtime, err
+	}
+	return e, mtime, nil
+}
diff --git a/fetch/fetch_test.go b/fetch/fetch_test.go
new file mode 100644
index 0000000..04c6e35
--- /dev/null
+++ b/fetch/fetch_test.go
@@ -0,0 +1,36 @@
+package fetch
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+)
+
+func TestFetchChangeLog(t *testing.T) {
+	server := httptest.NewServer(http.FileServer(http.Dir("../changelog/testdata/")))
+	defer server.Close()
+
+	r := Repo{
+		URL: server.URL,
+	}
+
+	e, mtime, err := r.ChangeLog()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	expectedLen := 52
+	if len(e) != expectedLen {
+		t.Errorf("expected %d entries; got %d", expectedLen, len(e))
+	}
+
+	stat, err := os.Stat("../changelog/testdata/ChangeLog.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if mtime.Unix() != stat.ModTime().Unix() {
+		t.Errorf("time stamps not the same: expected %d; got %d", stat.ModTime().Unix(), mtime.Unix())
+	}
+}