micro/util/router/compile.go
Vasiliy Tolstov bbbcb22565 fieldalignment of all structs to save memory
Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
2021-03-06 19:45:13 +03:00

111 lines
2.1 KiB
Go

package router
// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/protoc-gen-grpc-gateway/httprule/compile.go
const (
opcodeVersion = 1
)
// Template is a compiled representation of path templates.
type Template struct {
// Verb is a VERB part in the template
Verb string
// Original template (example: /v1/a_bit_of_everything)
Template string
// OpCodes is a sequence of operations
OpCodes []int
// Pool is a constant pool
Pool []string
// Fields is a list of field paths bound in this template
Fields []string
// Version is the version number of the format
Version int
}
// 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 {
str string
code OpCode
operand int
}
func (w wildcard) compile() []op {
return []op{
{code: OpPush},
}
}
func (w deepWildcard) compile() []op {
return []op{
{code: OpPushM},
}
}
func (l literal) compile() []op {
return []op{
{
code: OpLitPush,
str: string(l),
},
}
}
func (v variable) compile() []op {
ops := make([]op, 0, len(v.segments))
for _, s := range v.segments {
ops = append(ops, s.compile()...)
}
ops = append(ops, op{
code: OpConcatN,
operand: len(v.segments),
}, op{
code: OpCapture,
str: v.path,
})
return ops
}
func (t template) Compile() Template {
rawOps := make([]op, 0, len(t.segments))
for _, s := range t.segments {
rawOps = append(rawOps, s.compile()...)
}
//ops := make([]int, 0, len(rawOps))
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.operand)
} 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 == OpCapture {
fields = append(fields, op.str)
}
}
return Template{
Version: opcodeVersion,
OpCodes: ops,
Pool: pool,
Verb: t.verb,
Fields: fields,
Template: t.template,
}
}