feat: add httpc.Parse (#1698)

rest/internal/encoding/parser.go

@@ -0,0 +1,27 @@
+package encoding
+
+import (
+	"net/http"
+	"net/textproto"
+
+	"github.com/zeromicro/go-zero/core/mapping"
+)
+
+const headerKey = "header"
+
+var headerUnmarshaler = mapping.NewUnmarshaler(headerKey, mapping.WithStringValues(),
+	mapping.WithCanonicalKeyFunc(textproto.CanonicalMIMEHeaderKey))
+
+// ParseHeaders parses the headers request.
+func ParseHeaders(header http.Header, v interface{}) error {
+	m := map[string]interface{}{}
+	for k, v := range header {
+		if len(v) == 1 {
+			m[k] = v[0]
+		} else {
+			m[k] = v
+		}
+	}
+
+	return headerUnmarshaler.Unmarshal(m, v)
+}

rest/internal/encoding/parser_test.go

@@ -0,0 +1,40 @@
+package encoding
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseHeaders(t *testing.T) {
+	var val struct {
+		Foo string `header:"foo"`
+		Baz int    `header:"baz"`
+		Qux bool   `header:"qux,default=true"`
+	}
+	r := httptest.NewRequest(http.MethodGet, "/any", nil)
+	r.Header.Set("foo", "bar")
+	r.Header.Set("baz", "1")
+	assert.Nil(t, ParseHeaders(r.Header, &val))
+	assert.Equal(t, "bar", val.Foo)
+	assert.Equal(t, 1, val.Baz)
+	assert.True(t, val.Qux)
+}
+
+func TestParseHeadersMulti(t *testing.T) {
+	var val struct {
+		Foo []string `header:"foo"`
+		Baz int      `header:"baz"`
+		Qux bool     `header:"qux,default=true"`
+	}
+	r := httptest.NewRequest(http.MethodGet, "/any", nil)
+	r.Header.Set("foo", "bar")
+	r.Header.Add("foo", "bar1")
+	r.Header.Set("baz", "1")
+	assert.Nil(t, ParseHeaders(r.Header, &val))
+	assert.Equal(t, []string{"bar", "bar1"}, val.Foo)
+	assert.Equal(t, 1, val.Baz)
+	assert.True(t, val.Qux)
+}