Fix linux build

client/color/color_linux.go

@@ -0,0 +1,43 @@
+package color
+
+import (
+	"os"
+
+	auroraLib "github.com/logrusorgru/aurora"
+	"github.com/mattn/go-isatty"
+)
+
+// We're using a couple of libraries that produce ANSI escape sequences to print
+// colored text:
+//
+// * aurora
+// * zerolog
+//
+// Ideally, both of these libraries would support the standard NO_COLOR
+// environment variable, but they don't, so we need to handle it ourselves.
+// Fortunately, both libraries include an option to disable colors, so we can
+// check for NO_COLOR ourselves and disable color manually if needed.
+//
+// Another consideration is that not all terminal environments support ANSI
+// escape codes (the Windows 7 CMD terminal doesn't, for example). So, we try to
+// detect that scenario and disable colors. It would be good to do this in a
+// more robust way, something like checking the terminfo/termcap capabilities of
+// the terminal to see if it's capable of interpreting ANSI escape sequences,
+// but that seems complex and error prone and I'm not really sure that it's
+// worth it. So I'm taking a more basic approach here, where we just check to
+// see if the terminal is a TTY and assume that if it is a TTY, then it can
+// probably interpret ANSI escape sequences.
+//
+// Reference:
+// https://github.com/logrusorgru/aurora/issues/2
+// https://eklitzke.org/ansi-color-codes
+var EnableColor = isatty.IsTerminal(os.Stdout.Fd()) &&
+	len(os.Getenv("NO_COLOR")) == 0
+
+var Aurora auroraLib.Aurora
+
+func init() {
+	// HACK: Ideally, aurora would support NO_COLOR, but at least they give us a
+	// config option so that we can disable color manually.
+	Aurora = auroraLib.NewAurora(EnableColor)
+}