feat(checker): port other checkers over

Signed-off-by: Xe Iaso <me@xeiaso.net>

lib/checker/headerexists/checker.go

@@ -0,0 +1,32 @@
+package headerexists
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/TecharoHQ/anubis/internal"
+	"github.com/TecharoHQ/anubis/lib/checker"
+)
+
+func New(key string) checker.Interface {
+	return headerExistsChecker{
+		header: strings.TrimSpace(http.CanonicalHeaderKey(key)),
+		hash:   internal.FastHash(key),
+	}
+}
+
+type headerExistsChecker struct {
+	header, hash string
+}
+
+func (hec headerExistsChecker) Check(r *http.Request) (bool, error) {
+	if r.Header.Get(hec.header) != "" {
+		return true, nil
+	}
+
+	return false, nil
+}
+
+func (hec headerExistsChecker) Hash() string {
+	return hec.hash
+}

lib/checker/headerexists/checker_test.go

@@ -0,0 +1,57 @@
+package headerexists
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"testing"
+)
+
+func TestChecker(t *testing.T) {
+	fac := Factory{}
+
+	for _, tt := range []struct {
+		name      string
+		header    string
+		reqHeader string
+		ok        bool
+	}{
+		{
+			name:      "match",
+			header:    "Authorization",
+			reqHeader: "Authorization",
+			ok:        true,
+		},
+		{
+			name:      "not_match",
+			header:    "Authorization",
+			reqHeader: "Authentication",
+		},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			hec, err := fac.Build(t.Context(), json.RawMessage(fmt.Sprintf("%q", tt.header)))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			t.Log(hec.Hash())
+
+			r, err := http.NewRequest(http.MethodGet, "/", nil)
+			if err != nil {
+				t.Fatalf("can't make request: %v", err)
+			}
+
+			r.Header.Set(tt.reqHeader, "hunter2")
+
+			ok, err := hec.Check(r)
+
+			if tt.ok != ok {
+				t.Errorf("ok: %v, wanted: %v", ok, tt.ok)
+			}
+
+			if err != nil {
+				t.Errorf("err: %v", err)
+			}
+		})
+	}
+}

lib/checker/headerexists/factory.go

@@ -0,0 +1,40 @@
+package headerexists
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"github.com/TecharoHQ/anubis/lib/checker"
+)
+
+type Factory struct{}
+
+func (f Factory) Build(ctx context.Context, data json.RawMessage) (checker.Interface, error) {
+	var headerName string
+
+	if err := json.Unmarshal([]byte(data), &headerName); err != nil {
+		return nil, fmt.Errorf("%w: want string", checker.ErrUnparseableConfig)
+	}
+
+	if err := f.Valid(ctx, data); err != nil {
+		return nil, err
+	}
+
+	return New(http.CanonicalHeaderKey(headerName)), nil
+}
+
+func (Factory) Valid(ctx context.Context, data json.RawMessage) error {
+	var headerName string
+
+	if err := json.Unmarshal([]byte(data), &headerName); err != nil {
+		return fmt.Errorf("%w: want string", checker.ErrUnparseableConfig)
+	}
+
+	if headerName == "" {
+		return fmt.Errorf("%w: string must not be empty", checker.ErrInvalidConfig)
+	}
+
+	return nil
+}

lib/checker/headerexists/factory_test.go

@@ -0,0 +1,60 @@
+package headerexists
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestFactoryGood(t *testing.T) {
+	files, err := os.ReadDir("./testdata/good")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fac := Factory{}
+
+	for _, fname := range files {
+		t.Run(fname.Name(), func(t *testing.T) {
+			data, err := os.ReadFile(filepath.Join("testdata", "good", fname.Name()))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if err := fac.Valid(t.Context(), json.RawMessage(data)); err != nil {
+				t.Fatal(err)
+			}
+		})
+	}
+}
+
+func TestFactoryBad(t *testing.T) {
+	files, err := os.ReadDir("./testdata/bad")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fac := Factory{}
+
+	for _, fname := range files {
+		t.Run(fname.Name(), func(t *testing.T) {
+			data, err := os.ReadFile(filepath.Join("testdata", "bad", fname.Name()))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			t.Run("Build", func(t *testing.T) {
+				if _, err := fac.Build(t.Context(), json.RawMessage(data)); err == nil {
+					t.Fatal(err)
+				}
+			})
+
+			t.Run("Valid", func(t *testing.T) {
+				if err := fac.Valid(t.Context(), json.RawMessage(data)); err == nil {
+					t.Fatal(err)
+				}
+			})
+		})
+	}
+}

lib/checker/headerexists/testdata/bad/empty.json

@@ -0,0 +1 @@
+""

lib/checker/headerexists/testdata/bad/object.json

@@ -0,0 +1 @@
+{}

lib/checker/headerexists/testdata/good/authorization.json

@@ -0,0 +1 @@
+"Authorization"