fix body with "*" bug

[ChenLingPeng]

this code says that when body is set to "*" in a rpc service, all the query param will map to the request body, but the truth is not. when body is "*", b.Body != nil && len(b.Body.FieldPath) will be true and we should continue the method

Signed-off-by: forrestchen forrestchen@tencent.com

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[johanbrandhorst]

I'm confused, are you saying that parameters provided as query parameters should be parsed when body: "*" is set? I'm not sure it's a correct interpretation of the rule. My interpretation is that any parameters not part of the path should be in the request body. Do you have a practical example of this instead of a hypothetical interpretation?

[ChenLingPeng]

In my case, I have a request
GET /v1/clusters?offset=0&limit=10
and request Body:

{"requestId":"xxx-xxx-xxx"}

[johanbrandhorst]

Leaving aside the point about having a body in a GET, what does your http.proto annotations look like for this RPC?

[ChenLingPeng]

message TsfListClusterRequest {
    string requestId = 1;
    int32 offset = 2;
    int32 limit = 3;
}

message TsfListClusterResponse {
    int32 code = 1;
    string message = 2;
    string requestId = 3;
    TsfListClusterData data = 4;
}

rpc ListClusters(TsfListClusterRequest) returns (TsfListClusterResponse) {
    option (google.api.http)  = {
        get: "/tsf/v1.0/clusters"
        body: "*"
    };
}

[googlebot]

CLAs look good, thanks!

[johanbrandhorst]

So judging by your annotations I think the wording in http.proto implies that the parameters should go in the body. You can't expect it to read it from query parameters and the body when you use "*". Have you tried just using body: "request_id"?

Also; you should really use snake_case for proto file field names. https://developers.google.com/protocol-buffers/docs/style

[ChenLingPeng]

when body is set to "request_id", the generate code is marshaler.NewDecoder(req.Body).Decode(&protoReq.RequestId) and will return an unmarshal error.

[johanbrandhorst]

What does that error look like?

[ChenLingPeng]

{"error":"json: cannot unmarshal object into Go value of type string","code":3}

[johanbrandhorst]

I'm wondering if that's a bug... it should be possible to have the specific parameter parsed from the body. Can you see why this is broken like this? You can't use * and expect query parameters to work.

[johanbrandhorst]

I think the premise of this PR is a flawed interpretation of http.proto, as I discussed in #234 (comment). Closing since the current behaviour is correct.