Documentation ¶
Overview ¶
`grpc_validator` is a generic request contents validator server-side middleware for gRPC.
Request Validator Middleware ¶
Validating input is important, and hard. It also causes a lot of boilerplate code. This middleware checks for the existence of a `Validate` method on each of the messages of a gRPC request. This includes the single request of the `Unary` calls, as well as each message of the inbound Stream calls. In case of a validation failure, an `InvalidArgument` gRPC status is returned, along with a description of the validation failure.
While it is generic, it was intended to be used with https://github.com/mwitkow/go-proto-validators, a Go protocol buffers codegen plugin that creates the `Validate` methods (including nested messages) based on declarative options in the `.proto` files themselves. For example:
syntax = "proto3"; package validator.examples; import "github.com/mwitkow/go-proto-validators/validator.proto"; message InnerMessage { // some_integer can only be in range (1, 100). int32 some_integer = 1 [(validator.field) = {int_gt: 0, int_lt: 100}]; // some_float can only be in range (0;1). double some_float = 2 [(validator.field) = {float_gte: 0, float_lte: 1}]; } message OuterMessage { // important_string must be a lowercase alpha-numeric of 5 to 30 characters (RE2 syntax). string important_string = 1 [(validator.field) = {regex: "^[a-z]{2,5}$"}]; // proto3 doesn't have `required`, the `msg_exist` enforces presence of InnerMessage. InnerMessage inner = 2 [(validator.field) = {msg_exists : true}]; }
The `OuterMessage.Validate` would include validation of regexes, existence of the InnerMessage and the range values within it. The `grpc_validator` middleware would then automatically use that to check all messages processed by the server.
Please consult https://github.com/mwitkow/go-proto-validators for details on `protoc` invocation and other parameters of customization.
Index ¶
Constants ¶
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Variables ¶
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Functions ¶
func StreamServerInterceptor ¶
func StreamServerInterceptor() grpc.StreamServerInterceptor
StreamServerInterceptor returns a new streaming server interceptor that validates incoming messages.
The stage at which invalid messages will be rejected with `InvalidArgument` varies based on the type of the RPC. For `ServerStream` (1:m) requests, it will happen before reaching any userspace handlers. For `ClientStream` (n:1) or `BidiStream` (n:m) RPCs, the messages will be rejected on calls to `stream.Recv()`.
func UnaryServerInterceptor ¶
func UnaryServerInterceptor() grpc.UnaryServerInterceptor
UnaryServerInterceptor returns a new unary server interceptor that validates incoming messages.
Invalid messages will be rejected with `InvalidArgument` before reaching any userspace handlers.
Types ¶
This section is empty.