package wrapper import ( "context" "strings" "github.com/micro/go-micro/v2/auth" "github.com/micro/go-micro/v2/client" "github.com/micro/go-micro/v2/debug/stats" "github.com/micro/go-micro/v2/debug/trace" "github.com/micro/go-micro/v2/errors" "github.com/micro/go-micro/v2/metadata" "github.com/micro/go-micro/v2/server" ) type clientWrapper struct { client.Client // Auth interface auth func() auth.Auth // headers to inject headers metadata.Metadata } type traceWrapper struct { client.Client name string trace trace.Tracer } var ( HeaderPrefix = "Micro-" ) func (c *clientWrapper) setHeaders(ctx context.Context) context.Context { // don't overwrite keys return metadata.MergeContext(ctx, c.headers, false) } func (c *clientWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error { ctx = c.setHeaders(ctx) return c.Client.Call(ctx, req, rsp, opts...) } func (c *clientWrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) { ctx = c.setHeaders(ctx) return c.Client.Stream(ctx, req, opts...) } func (c *clientWrapper) Publish(ctx context.Context, p client.Message, opts ...client.PublishOption) error { ctx = c.setHeaders(ctx) return c.Client.Publish(ctx, p, opts...) } func (c *traceWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error { newCtx, s := c.trace.Start(ctx, req.Service()+"."+req.Endpoint()) s.Type = trace.SpanTypeRequestOutbound err := c.Client.Call(newCtx, req, rsp, opts...) if err != nil { s.Metadata["error"] = err.Error() } // finish the trace c.trace.Finish(s) return err } // FromService wraps a client to inject service and auth metadata func FromService(name string, c client.Client, fn func() auth.Auth) client.Client { return &clientWrapper{ c, fn, metadata.Metadata{ HeaderPrefix + "From-Service": name, }, } } // HandlerStats wraps a server handler to generate request/error stats func HandlerStats(stats stats.Stats) server.HandlerWrapper { // return a handler wrapper return func(h server.HandlerFunc) server.HandlerFunc { // return a function that returns a function return func(ctx context.Context, req server.Request, rsp interface{}) error { // execute the handler err := h(ctx, req, rsp) // record the stats stats.Record(err) // return the error return err } } } // TraceCall is a call tracing wrapper func TraceCall(name string, t trace.Tracer, c client.Client) client.Client { return &traceWrapper{ name: name, trace: t, Client: c, } } // TraceHandler wraps a server handler to perform tracing func TraceHandler(t trace.Tracer) server.HandlerWrapper { // return a handler wrapper return func(h server.HandlerFunc) server.HandlerFunc { // return a function that returns a function return func(ctx context.Context, req server.Request, rsp interface{}) error { // don't store traces for debug if strings.HasPrefix(req.Endpoint(), "Debug.") { return h(ctx, req, rsp) } // get the span newCtx, s := t.Start(ctx, req.Service()+"."+req.Endpoint()) s.Type = trace.SpanTypeRequestInbound err := h(newCtx, req, rsp) if err != nil { s.Metadata["error"] = err.Error() } // finish t.Finish(s) return err } } } // AuthHandler wraps a server handler to perform auth func AuthHandler(fn func() auth.Auth) server.HandlerWrapper { return func(h server.HandlerFunc) server.HandlerFunc { return func(ctx context.Context, req server.Request, rsp interface{}) error { // get the auth.Auth interface a := fn() // Check for debug endpoints which should be excluded from auth if strings.HasPrefix(req.Endpoint(), "Debug.") { return h(ctx, req, rsp) } // Extract the token if present. Note: if noop is being used // then the token can be blank without erroring var token string if header, ok := metadata.Get(ctx, "Authorization"); ok { // Ensure the correct scheme is being used if !strings.HasPrefix(header, auth.BearerScheme) { return errors.Unauthorized(req.Service(), "invalid authorization header. expected Bearer schema") } token = header[len(auth.BearerScheme):] } // Inspect the token and get the account account, err := a.Inspect(token) if err != nil { account = &auth.Account{Namespace: a.Options().Namespace} } // construct the resource res := &auth.Resource{ Type: "service", Name: req.Service(), Endpoint: req.Endpoint(), } // Verify the caller has access to the resource err = a.Verify(account, res) if err != nil && len(account.ID) > 0 { return errors.Forbidden(req.Service(), "Forbidden call made to %v:%v by %v", req.Service(), req.Endpoint(), account.ID) } else if err != nil { return errors.Unauthorized(req.Service(), "Unauthorised call made to %v:%v", req.Service(), req.Endpoint()) } // There is an account, set it in the context ctx, err = auth.ContextWithAccount(ctx, account) if err != nil { return err } // The user is authorised, allow the call return h(ctx, req, rsp) } } }