> 1. When grpc-web client sends a request, it will generate a route according to the package.service.function rule in the .proto file defined. If we want to access through "/example/*" instead of "/*" when setting up the route, the URI we get in the gateway at this time is "/example/package.service.function", but grpc Server needs " package.service.function", so the user can use "strip_path" to decide whether to delete the prefix.
It sounds that we need to always remove the prefix in this case. As "/example/package.service.function" isn't valid proto name. Maybe we can use the code in https://github.com/apache/apisix/blob/3c0c89a58ee872c9564ded3fe6e8998f96235489/apisix/plugins/serverless/generic-upstream.lua#L76, which strips the path automatically if it is matched by the wildcard. JinChao Shuai <shuaijinc...@apache.org> 于2021年12月23日周四 18:40写道： > > hi, chao > > 1. When grpc-web client sends a request, it will generate a route according > to the package.service.function rule in the .proto file defined. If we want > to access through "/example/*" instead of "/*" when setting up the route, > the URI we get in the gateway at this time is > "/example/package.service.function", but grpc Server needs " > package.service.function", so the user can use "strip_path" to decide > whether to delete the prefix. > > 2. There is an introduction about the agreement in the link [5]. > The JavaScript client provides two data transmission methods. > The first is the text method. We need to determine the encryption method > through the mimetype in the gateway, then use its corresponding decryption > method to decrypt, reset it to the body, and forward it to the upstream > request. After grpcServer responds, it needs to be encrypted in the same > way to respond to the client. > Data in another binary format can be forwarded directly, and the gateway > only needs to process CORS and the conversion of requests and responses > mime. > > > Chao Zhang <tok...@apache.org> 于2021年12月23日周四 16:23写道： > > > Hi! > > > > Sounds good to me, but still I want to pick your brain to resolve some > > confusions. > > > > 1. I'm confused with the `strip_path` field, could you give some more > > elaborated examples? > > 2. Still don't know how Apache APISIX can support such protocol > > conversion. How does Apache APISIX convert the data in gRPC web format > > to gRPC format? > > > > Best regards > > Chao Zhang > > > > https://github.com/tokers > > > > On Thu, Dec 23, 2021 at 4:00 PM JinChao Shuai <shuaijinc...@apache.org> > > wrote: > > > > > > Hi, folks > > > > > > gRPC was originally developed by Google and is a high-performance remote > > > procedure call framework based on HTTP/2 implementation. But because the > > > browser does not directly expose HTTP/2, Web applications cannot directly > > > use gRPC. > > > gRPC-Web is a standardized protocol that solves this problem. You can use > > > gRPC in the browser and provide a JavaScript implementation of gRPC for > > the > > > browser client. > > > The principle is to create an end-to-end gRPC pipeline that is compatible > > > with HTTP/1.1 and HTTP/2, and then the browser sends a regular HTTP > > request > > > to the gRPC-Web between the browser and the server The proxy converts the > > > request and response. > > > > > > Currently Envoy provides proxy and conversion capabilities of the > > gRPC-Web > > > protocol. I think Apache APISIX can provide friendly proxy support for > > > gRPC-Web through plugin, which is meaningful to front-end developers. You > > > can use a more native way to develop microservices or applications based > > on > > > gRPC. > > > > > > The following are the relevant configuration and technical details. > > > > > > Plugin Name: > > > > > > - grpc-web > > > > > > > > > Plugin Configuration: > > > > > > { > > > "strip_path":false > > > } > > > > > > strip_path: strip request routing prefix, If set to true, stripped > > request > > > path will be passed to upstream gRPC service > > > > > > > > > Detail: > > > > > > 1、What Apache APISIX needs to do ? > > > > > > gRPC-Web Client <--> Proxy <--> gRPC Service > > > > > > Implement Proxy, complete the decoding of data from gRPC-Web data to gRPC > > > Server and the encoding of gRPC Server response to gRPC-Web. > > > > > > 2、Data Format: Use the protoc-gen-grpc-web plugin to generate proto > > > messages and the service client stub from your .proto > > > > > > 2.1 protoc-gen-grpc-web mode=grpcwebtext: The default generated code > > sends > > > the payload in the grpc-web-text format. > > > - Content-type: application/grpc-web-text > > > - Payload are base64-encoded. > > > - Both unary and server streaming calls are supported. > > > > > > 2.2 protoc-gen-grpc-web mode=grpcweb: A binary protobuf format is also > > > supported. > > > - Content-type: application/grpc-web+proto > > > - Payload are in the binary protobuf format. > > > - Only unary calls are supported for now. > > > > > > refer to: [1] > > > > > > 3、CORS Support: > > > > > > 3.1 Should follow the CORS spec (Mandatory) > > > - Access-Control-Allow-Credentials to allow Authorization headers > > > - Access-Control-Allow-Methods to allow POST and (preflight) OPTIONS only > > > - Access-Control-Allow-Headers to whatever the preflight request carries > > > > > > 3.2 The client library is expected to support header overwrites to avoid > > > preflight > > > > > > 3.3 CSP support to be specified > > > > > > refer to: [2] > > > > > > For more information and use about grpc-web protocol, please refer to: > > > [3]、[4]、[5] > > > > > > [1] > > > > > https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-WEB.md#protocol-differences-vs-grpc-over-http2 > > > [2] > > > > > https://github.com/grpc/grpc-web/blob/master/doc/browser-features.md#cors-support > > > [3] https://www.npmjs.com/package/grpc-web > > > [4] https://github.com/grpc/grpc-web/blob/master/doc/browser-features.md > > > [5] https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-WEB.md > > > > > > > > > -- > > > Thanks, > > > Janko > > > > > -- > Thanks, > Janko
