package client import ( "crypto/ecdsa" "fmt" "github.com/nspcc-dev/neofs-api-go/v2/refs" "github.com/nspcc-dev/neofs-api-go/v2/rpc/client" v2session "github.com/nspcc-dev/neofs-api-go/v2/session" "github.com/nspcc-dev/neofs-api-go/v2/signature" apistatus "github.com/nspcc-dev/neofs-sdk-go/client/status" "github.com/nspcc-dev/neofs-sdk-go/version" ) // common interface of resulting structures with API status. type resCommon interface { setStatus(apistatus.Status) } // structure is embedded to all resulting types in order to inherit status-related methods. type statusRes struct { st apistatus.Status } // setStatus implements resCommon interface method. func (x *statusRes) setStatus(st apistatus.Status) { x.st = st } // Status returns server's status return. // // Use apistatus package functionality to handle the status. func (x statusRes) Status() apistatus.Status { return x.st } // groups meta parameters shared between all Client operations. type prmCommonMeta struct { // NeoFS request X-Headers xHeaders []string } // WithXHeaders specifies list of extended headers (string key-value pairs) // to be attached to the request. Must have an even length. // // Slice must not be mutated until the operation completes. func (x *prmCommonMeta) WithXHeaders(hs ...string) { if len(hs)%2 != 0 { panic("slice of X-Headers with odd length") } x.xHeaders = hs } func (x prmCommonMeta) writeToMetaHeader(h *v2session.RequestMetaHeader) { if len(x.xHeaders) > 0 { hs := make([]v2session.XHeader, len(x.xHeaders)/2) for i := 0; i < len(x.xHeaders); i += 2 { hs[i].SetKey(x.xHeaders[i]) hs[i].SetValue(x.xHeaders[i+1]) } h.SetXHeaders(hs) } } func writeXHeadersToMeta(xHeaders []string, h *v2session.RequestMetaHeader) { if len(xHeaders) == 0 { return } hs := make([]v2session.XHeader, len(xHeaders)/2) for i := 0; i < len(xHeaders); i += 2 { hs[i].SetKey(xHeaders[i]) hs[i].SetValue(xHeaders[i+1]) } h.SetXHeaders(hs) } // panic messages. const ( panicMsgMissingContext = "missing context" panicMsgMissingContainer = "missing container" panicMsgMissingObject = "missing object" ) // groups all the details required to send a single request and process a response to it. type contextCall struct { // ================================================== // state vars that do not require explicit initialization // final error to be returned from client method err error // received response resp responseV2 // ================================================== // shared parameters which are set uniformly on all calls // request signing key key ecdsa.PrivateKey // callback prior to processing the response by the client callbackResp func(ResponseMetaInfo) error // if set, protocol errors will be expanded into a final error resolveAPIFailures bool // NeoFS network magic netMagic uint64 // Meta parameters meta prmCommonMeta // ================================================== // custom call parameters // structure of the call result statusRes resCommon // request to be signed with a key and sent req request // function to send a request (unary) and receive a response call func() (responseV2, error) // function to send the request (req field) wReq func() error // function to recv the response (resp field) rResp func() error // function to close the message stream closer func() error // function of writing response fields to the resulting structure (optional) result func(v2 responseV2) } type request interface { GetMetaHeader() *v2session.RequestMetaHeader SetMetaHeader(*v2session.RequestMetaHeader) SetVerificationHeader(*v2session.RequestVerificationHeader) } // sets needed fields of the request meta header. func (x contextCall) prepareRequest() { meta := x.req.GetMetaHeader() if meta == nil { meta = new(v2session.RequestMetaHeader) x.req.SetMetaHeader(meta) } if meta.GetTTL() == 0 { meta.SetTTL(2) } if meta.GetVersion() == nil { var verV2 refs.Version version.Current().WriteToV2(&verV2) meta.SetVersion(&verV2) } meta.SetNetworkMagic(x.netMagic) x.meta.writeToMetaHeader(meta) } func (c *Client) prepareRequest(req request, meta *v2session.RequestMetaHeader) { ttl := meta.GetTTL() if ttl == 0 { ttl = 2 } verV2 := meta.GetVersion() if verV2 == nil { verV2 = new(refs.Version) version.Current().WriteToV2(verV2) } meta.SetTTL(ttl) meta.SetVersion(verV2) meta.SetNetworkMagic(c.prm.netMagic) req.SetMetaHeader(meta) } // prepares, signs and writes the request. Result means success. // If failed, contextCall.err contains the reason. func (x *contextCall) writeRequest() bool { x.prepareRequest() x.req.SetVerificationHeader(nil) // sign the request x.err = signature.SignServiceMessage(&x.key, x.req) if x.err != nil { x.err = fmt.Errorf("sign request: %w", x.err) return false } x.err = x.wReq() if x.err != nil { x.err = fmt.Errorf("write request: %w", x.err) return false } return true } // performs common actions of response processing and writes any problem as a result status or client error // (in both cases returns false). // // Actions: // - verify signature (internal); // - call response callback (internal); // - unwrap status error (optional). func (x *contextCall) processResponse() bool { // call response callback if set if x.callbackResp != nil { x.err = x.callbackResp(ResponseMetaInfo{ key: x.resp.GetVerificationHeader().GetBodySignature().GetKey(), epoch: x.resp.GetMetaHeader().GetEpoch(), }) if x.err != nil { x.err = fmt.Errorf("response callback error: %w", x.err) return false } } // note that we call response callback before signature check since it is expected more lightweight // while verification needs marshaling // verify response signature x.err = signature.VerifyServiceMessage(x.resp) if x.err != nil { x.err = fmt.Errorf("invalid response signature: %w", x.err) return false } // get result status st := apistatus.FromStatusV2(x.resp.GetMetaHeader().GetStatus()) // unwrap unsuccessful status and return it // as error if client has been configured so successfulStatus := apistatus.IsSuccessful(st) if x.resolveAPIFailures { x.err = apistatus.ErrFromStatus(st) } else { x.statusRes.setStatus(st) } return successfulStatus } // processResponse verifies response signature and converts status to an error if needed. func (c *Client) processResponse(resp responseV2) (apistatus.Status, error) { err := signature.VerifyServiceMessage(resp) if err != nil { return nil, fmt.Errorf("invalid response signature: %w", err) } st := apistatus.FromStatusV2(resp.GetMetaHeader().GetStatus()) if c.prm.resolveNeoFSErrors { return st, apistatus.ErrFromStatus(st) } return st, nil } // reads response (if rResp is set) and processes it. Result means success. // If failed, contextCall.err (or statusRes if resolveAPIFailures is set) contains the reason. func (x *contextCall) readResponse() bool { if x.rResp != nil { x.err = x.rResp() if x.err != nil { x.err = fmt.Errorf("read response: %w", x.err) return false } } return x.processResponse() } // closes the message stream (if closer is set) and writes the results (if result is set). // Return means success. If failed, contextCall.err contains the reason. func (x *contextCall) close() bool { if x.closer != nil { x.err = x.closer() if x.err != nil { x.err = fmt.Errorf("close RPC: %w", x.err) return false } } // write response to resulting structure if x.result != nil { x.result(x.resp) } return x.err == nil } // goes through all stages of sending a request and processing a response. Returns true if successful. // If failed, contextCall.err contains the reason. func (x *contextCall) processCall() bool { // set request writer x.wReq = func() error { var err error x.resp, err = x.call() return err } // write request ok := x.writeRequest() if !ok { return false } // read response ok = x.readResponse() if !ok { return x.err == nil } // close and write response to resulting structure ok = x.close() if !ok { return false } return x.err == nil } // initializes static cross-call parameters inherited from client. func (c *Client) initCallContext(ctx *contextCall) { ctx.key = c.prm.key ctx.resolveAPIFailures = c.prm.resolveNeoFSErrors ctx.callbackResp = c.prm.cbRespInfo ctx.netMagic = c.prm.netMagic } // ExecRaw executes f with underlying github.com/nspcc-dev/neofs-api-go/v2/rpc/client.Client // instance. Communicate over the Protocol Buffers protocol in a more flexible way: // most often used to transmit data over a fixed version of the NeoFS protocol, as well // as to support custom services. // // The f must not manipulate the client connection passed into it. // // Like all other operations, must be called after connecting to the server and // before closing the connection. // // See also Dial and Close. // See also github.com/nspcc-dev/neofs-api-go/v2/rpc/client package docs. func (c *Client) ExecRaw(f func(client *client.Client) error) error { return f(&c.c) }