Files
x/rewriter/plugin/http.go
T
ginuerzh 1b07475bf3 feat(forwarder): support plugin-based rewriter in HTTP body rewrite rules
Each rewriteBody/rewriteResponseBody/rewriteRequestBody rule can now
optionally reference a named rewriter plugin (HTTP/gRPC backend) via
the rewriter field. When set, body rewriting delegates to the plugin
rather than applying pattern/replacement, while content-type filtering
still applies.

Coincident fixes:
- rewriter/plugin/grpc: return nil when conn is nil (avoid nil-ptr panic)
- rewriter/plugin/http: drain response body in defer to prevent leaks
- config/parsing/rewriter: pass TimeoutOption to gRPC plugin
- config/parsing/service: warn when referenced rewriter is not registered
2026-06-27 22:52:17 +08:00

107 lines
2.0 KiB
Go

package rewriter
import (
"bytes"
"context"
"encoding/json"
"io"
"net/http"
"github.com/go-gost/core/logger"
"github.com/go-gost/core/rewriter"
"github.com/go-gost/x/internal/plugin"
)
type httpPluginRequest struct {
Data []byte `json:"data"`
Metadata []byte `json:"metadata"`
}
type httpPluginResponse struct {
OK bool `json:"ok"`
Data []byte `json:"data"`
}
type httpPlugin struct {
url string
client *http.Client
header http.Header
log logger.Logger
}
// NewHTTPPlugin creates a Rewriter plugin based on HTTP.
func NewHTTPPlugin(name string, url string, opts ...plugin.Option) rewriter.Rewriter {
var options plugin.Options
for _, opt := range opts {
opt(&options)
}
return &httpPlugin{
url: url,
client: plugin.NewHTTPClient(&options),
header: options.Header,
log: logger.Default().WithFields(map[string]any{
"kind": "rewriter",
"rewriter": name,
}),
}
}
func (p *httpPlugin) Rewrite(ctx context.Context, b []byte, opts ...rewriter.RewriteOption) ([]byte, error) {
if p.client == nil {
return b, nil
}
var options rewriter.RewriteOptions
for _, opt := range opts {
opt(&options)
}
md, err := json.Marshal(options.Metadata)
if err != nil {
return b, err
}
rb := httpPluginRequest{
Data: b,
Metadata: md,
}
v, err := json.Marshal(&rb)
if err != nil {
return b, err
}
req, err := http.NewRequestWithContext(ctx, http.MethodPost, p.url, bytes.NewReader(v))
if err != nil {
return b, err
}
if p.header != nil {
req.Header = p.header.Clone()
}
req.Header.Set("Content-Type", "application/json")
resp, err := p.client.Do(req)
if err != nil {
return b, err
}
defer resp.Body.Close()
defer io.Copy(io.Discard, resp.Body)
if resp.StatusCode != http.StatusOK {
return b, nil
}
res := httpPluginResponse{}
if err := json.NewDecoder(resp.Body).Decode(&res); err != nil {
return b, err
}
if !res.OK {
return b, nil
}
if res.Data != nil {
return res.Data, nil
}
return b, nil
}