glide up

vendor/github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway/httprule/compile.go

@@ -0,0 +1,117 @@
+package httprule
+
+import (
+	"github.com/grpc-ecosystem/grpc-gateway/utilities"
+)
+
+const (
+	opcodeVersion = 1
+)
+
+// Template is a compiled representation of path templates.
+type Template struct {
+	// Version is the version number of the format.
+	Version int
+	// OpCodes is a sequence of operations.
+	OpCodes []int
+	// Pool is a constant pool
+	Pool []string
+	// Verb is a VERB part in the template.
+	Verb string
+	// Fields is a list of field paths bound in this template.
+	Fields []string
+	// Original template (example: /v1/a_bit_of_everything)
+	Template string
+}
+
+// Compiler compiles utilities representation of path templates into marshallable operations.
+// They can be unmarshalled by runtime.NewPattern.
+type Compiler interface {
+	Compile() Template
+}
+
+type op struct {
+	// code is the opcode of the operation
+	code utilities.OpCode
+
+	// str is a string operand of the code.
+	// num is ignored if str is not empty.
+	str string
+
+	// num is a numeric operand of the code.
+	num int
+}
+
+func (w wildcard) compile() []op {
+	return []op{
+		{code: utilities.OpPush},
+	}
+}
+
+func (w deepWildcard) compile() []op {
+	return []op{
+		{code: utilities.OpPushM},
+	}
+}
+
+func (l literal) compile() []op {
+	return []op{
+		{
+			code: utilities.OpLitPush,
+			str:  string(l),
+		},
+	}
+}
+
+func (v variable) compile() []op {
+	var ops []op
+	for _, s := range v.segments {
+		ops = append(ops, s.compile()...)
+	}
+	ops = append(ops, op{
+		code: utilities.OpConcatN,
+		num:  len(v.segments),
+	}, op{
+		code: utilities.OpCapture,
+		str:  v.path,
+	})
+
+	return ops
+}
+
+func (t template) Compile() Template {
+	var rawOps []op
+	for _, s := range t.segments {
+		rawOps = append(rawOps, s.compile()...)
+	}
+
+	var (
+		ops    []int
+		pool   []string
+		fields []string
+	)
+	consts := make(map[string]int)
+	for _, op := range rawOps {
+		ops = append(ops, int(op.code))
+		if op.str == "" {
+			ops = append(ops, op.num)
+		} else {
+			if _, ok := consts[op.str]; !ok {
+				consts[op.str] = len(pool)
+				pool = append(pool, op.str)
+			}
+			ops = append(ops, consts[op.str])
+		}
+		if op.code == utilities.OpCapture {
+			fields = append(fields, op.str)
+		}
+	}
+	return Template{
+		Version:  opcodeVersion,
+		OpCodes:  ops,
+		Pool:     pool,
+		Verb:     t.verb,
+		Fields:   fields,
+		Template: t.template,
+	}
+}