Let me give a pretty clear answer from a Java developer. 99% of Java developers today, who are writing business logic, are only focusing on Spring framework. Especially, we are talking about Spring Gateway. Who will write that's filter w/o Spring libraries or core? You could try to find a real case, I think it is hard to find.
What this proposal was discussed, no because Java VS LUA, it is about Java ecosystem and Spring ecosystem. Sheng Wu 吴晟 Twitter, wusheng1108 ZhengSong Tu <tzssanggl...@gmail.com> 于2021年4月29日周四 下午5:26写道： > I have some questions about the Java plugin runner to discuss. > > Topic 1: Technical selection of communication protocols > java did not provide support for unix domain sockets until jdk16, but > obviously we will not be so aggressive in choosing jdk16, at this stage we > focus on jdk 8, so in order to implement java's unix domain sockets under > jdk8, we have two optional technology stacks > Option 1 - junixsocket, for more information please refer to the github > address: https://github.com/kohlschutter/junixsocket > Option 2-netty: For more information, please refer to github at > https://github.com/netty/netty > Before I was inclined to go for junixsocket because it is more pure, now I > am inclined to go for netty because it is more mature, I would like to know > your votes on this. > > Topic 2: Does it depend on spring-boot? > Do we need to fully rely on the spring-boot framework as a base to > implement the java plugin runner in phase 1? > In terms of audience, spring-boot has a broader audience and is easier to > integrate with the components of the spring boot ecosystem, and it is > faster to build on spring-boot. What do you think? > > Topic 3: Responsibilities of the SDK. > We should provide an SDK, which defines some base class objects and > function interfaces that users can use to write their own plugins based on > the SDK, similar to the filter form. Users need to package their own code > as a jar and declare the dependencies of their code in the configuration > file. So that java's plugin runner can load the user's typed jar at > startup. Is there anything that needs to be fixed in the above process? > > > Sheng Wu <wu.sheng.841...@gmail.com> 于2021年4月27日周二 上午10:00写道： > > > OK, if it is a development kit, I want to know whether it is really a > > runtime? Because eventually, whether debugging is friendly or not, rely > on > > this. > > > > Sheng Wu 吴晟 > > Twitter, wusheng1108 > > > > > > Daming <dam...@apache.org> 于2021年4月27日周二 上午9:57写道： > > > > > PDK stands for Plugin Development Kit. > > > It is a good choice to build on spring-boot in the initial stage. > > > Because it is very friendly and easy to get started for Java > > > developers(plugins developers). > > > > > > > > > Sheng Wu <wu.sheng.841...@gmail.com> 于2021年4月27日周二 上午9:31写道： > > > > > > > > I can't see the detail from the graph. > > > > But if we are speaking of Java and Spring gateway ecosystem, you > should > > > > know, that is not just interfaces. > > > > Spring boot, annotation system, IoC, AOP are all going to be there. > So, > > > > basically, I would recommend you to boot the codes as all > Spring-based > > > > applications did. > > > > BTW, I am not sure what PDK means. > > > > > > > > And about debugging, once your APISIX process could access the JVM > > > through > > > > a socket with manual localhost:port, it is fine for the Java > developer > > to > > > > start this sidecar in the IDEA. > > > > > > > > Sheng Wu 吴晟 > > > > Twitter, wusheng1108 > > > > > > > > > > > > ZhengSong Tu <tzssanggl...@gmail.com> 于2021年4月26日周一 上午11:47写道： > > > > > > > > > I have sketched the flow of the java side of the plugin runner > > > > > [image: APISIX 运行 Java 插件.png] > > > > > > > > > > And I have some questions to clarify. > > > > > > > > > > 1. How does the plugin runner load the client's code? > > > > > It's up to each runner to figure it out according to its own > > > > > language's ecology. Take java as an example, > > > > > the user develops with the PDK provided by us, and packages the > > custom > > > > > plugin code into a jar and puts it in the specified location. When > > the > > > > > plugin runner starts, it loads the jar package in this location by > > > means of > > > > > a custom dynamic ClassLoader or something like that. > > > > > > > > > > 2. How do users develop? > > > > > Just provide the filter chain like Spring Cloud Gateway. Users > > can > > > > > register their own filters. And the PDK is a jar, with some defined > > > > > interfaces such as pre, post, etc., and some objects such as > request, > > > > > header, etc. > > > > > > > > > > 3. How to debug？ > > > > > Option 1: APISIX provides debugging mode for java plugins, > this > > > time > > > > > it is not APISIX to start the plugin runner, but the user himself > > > downloads > > > > > the plugin runner code and runs the main method to start it, so as > to > > > > > construct a request to access APISIX, APISIX will pass the context > of > > > the > > > > > request to the plugin runner, and then use it to debug java code. > > > > > Option 2: java remote debug. > > > > > > > > > > > > > > > > > > > > Zexuan Luo <spacewan...@apache.org> 于2021年4月19日周一 下午6:18写道： > > > > > > > > > >> Here is the new flatbuffer schema: > > > > >> > > > > >> > > > > > > https://github.com/spacewander/incubator-apisix/blob/step1/apisix/plugins/ext-plugin/ext-plugin.fbs > > > > >> > > > > >> Zexuan Luo <spacewan...@apache.org> 于2021年4月16日周五 下午2:52写道： > > > > >> > > > > > >> > 1. Background > > > > >> > > > > > >> > APISIX currently only supports writing plugins in Lua. If other > > > > >> > languages are supported, it will greatly broaden the APISIX > > > ecosystem > > > > >> > and user base. > > > > >> > > > > > >> > 2. Solution > > > > >> > > > > > >> > Since WASM is not yet mature, we consider implementing it > through > > > local > > > > >> IPC. > > > > >> > > > > > >> > For the sake of discussion, the following will assume that the > > > plugin > > > > >> > is written in Java. However, in practice, our solution can be > > > > >> > interfaced with other languages. > > > > >> > > > > > >> > 2.1 Terminology > > > > >> > > > > > >> > Several terms are defined here. > > > > >> > > > > > >> > Plugin Runner: The service that runs the plugin, written in the > > same > > > > >> > language as the plugin. In the first version, we assume that > there > > > > >> > will be only one Plugin Runner. > > > > >> > > > > > >> > 2.2 Plugin Runner lifecycle > > > > >> > > > > > >> > To simplify user operation and reduce the difficulty of > upgrading, > > > > >> > Plugin Runner is managed by APISIX. > > > > >> > > > > > >> > APISIX starts the Plugin Runner when it starts and ends it when > it > > > > >> > ends. if the Plugin Runner quits in the middle, APISIX will > > restart > > > it > > > > >> > automatically. > > > > >> > > > > > >> > 2.3 Timing of APISIX communication with Plugin Runner > > > > >> > > > > > >> > ``` > > > > >> > Router ----> Global Plugin (written in Lua) ---> Ext Plugin > > > > >> > (ext-plugin-pre-req) ----> Lua Plugin (Router) > > > > >> > ---> Ext plugin (ext-plugin-post-req) ---> Upstream > > > > >> > ``` > > > > >> > > > > > >> > Running the Ext Plugin in the Global Plugin is not supported at > > this > > > > >> > time, as the global logic can be executed uniformly in the > Plugin > > > > >> > Runner. > > > > >> > > > > > >> > Running Ext Plugin after getting an upstream response is not > > > supported > > > > >> > at this time. We can support it later with a buffering response. > > > > >> > > > > > >> > ext-plugin-pre runs before all non-global Lua plugins, and > > > > >> > ext-plugin-post runs after all non-global Lua plugins. > > > > >> > > > > > >> > 2.4 How APISIX communicates with Plugin Runner > > > > >> > > > > > >> > APISIX communicates with Plugin Runner through a unix socket. > The > > > > >> > communication protocol is as follows. > > > > >> > > > > > >> > 2.4.1 Communication format > > > > >> > > > > > >> > ``` > > > > >> > 1 byte of type + 3 bytes of length + data > > > > >> > ``` > > > > >> > > > > > >> > The type can be 0 ~ 7, and the length can be [0, 8M). data > length > > is > > > > >> > determined by length. > > > > >> > Since Ext Plugin usually does not exchange too much data, 8M > > should > > > be > > > > >> > enough. The reason for taking 4 bytes is to keep the header > small > > > > >> > enough to be read efficiently. > > > > >> > > > > > >> > The current type takes the following values. > > > > >> > > > > > >> > 0 means error > > > > >> > 1 means prepare_conf > > > > >> > 2 means http_req_call > > > > >> > > > > > >> > The data is serialized in capnproto, a binary serialization > > format. > > > > >> > > > > > >> > capnproto is supported by many programming languages: > > > > >> > https://capnproto.org/otherlang.html > > > > >> > > > > > >> > The advantages of choosing capnproto are. > > > > >> > 1. focus on serialization performance > > > > >> > 2. partial deserialization support, so that decode can be done > > only > > > > >> > when it is needed > > > > >> > > > > > >> > 2.4.2 Communication steps > > > > >> > > > > > >> > Each ext plugin will have the following configuration. > > > > >> > > > > > >> > ``` > > > > >> > { > > > > >> > "conf": [ > > > > >> > { > > > > >> > "name": "configuration name", > > > > >> > "value": "configuration value" > > > > >> > } > > > > >> > ], > > > > >> > "extra_info": [ > > > > >> > ... > > > > >> > ] > > > > >> > } > > > > >> > ``` > > > > >> > > > > > >> > conf can be used to set the execution configuration of the > > > > >> > plugin-related requests inside Plugin Runner. > > > > >> > > > > > >> > The default data sent to Plugin Runner is only the most common > > > > >> > information. If you want additional information, you need to > > declare > > > > >> > it in extra_info beforehand. > > > > >> > > > > > >> > To save communication costs, conf is sent separately. > > > > >> > > > > > >> > 1. APISIX will check if conf has a corresponding token in the > > local > > > > >> cache. > > > > >> > 2. If not, APISIX sends a prepare_conf request to ask Plugin > > Runner > > > > >> > to cache the conf and return a token. > > > > >> > (Note that Plugin Runner's cache time needs to be longer than > > > APISIX's > > > > >> > cache time.) > > > > >> > 3. APISIX sends an http_req_call request to Plugin Runner. > > > > >> > 4. Plugin Runner executes the request and returns a response to > > > APISIX. > > > > >> > 5. APISIX processes the request based on the response > > > > >> > > > > > >> > 2.4.3 proto > > > > >> > > > > > >> > Refer to https://capnproto.org/language.html > > > > >> > > > > > >> > The following is the proto for error > > > > >> > > > > > >> > response > > > > >> > ``` > > > > >> > enum ErrorCode { > > > > >> > BAD_REQUEST @0; # Plugin Runner can't understand APISIX > > > > >> > SERVICE_UNAVAILABLE @1; # Plugin Runner can't handle the > > request > > > > >> > CONF_TOKEN_NOT_FOUND @2; > > > > >> > } > > > > >> > struct ErrorResp { > > > > >> > Code @0 :ErrorCode; > > > > >> > } > > > > >> > ``` > > > > >> > > > > > >> > The following is the proto of prepare_conf > > > > >> > > > > > >> > request > > > > >> > ``` > > > > >> > struct PrepareConfReq { > > > > >> > conf @0 :List(Pair); > > > > >> > } > > > > >> > ``` > > > > >> > > > > > >> > Response > > > > >> > ``` > > > > >> > struct PrepareConfResp { > > > > >> > conf_token @0 :UInt32; > > > > >> > } > > > > >> > ``` > > > > >> > > > > > >> > Here is the proto for http_req_call > > > > >> > > > > > >> > request > > > > >> > ``` > > > > >> > struct Pair { > > > > >> > name @0 :Text; > > > > >> > value @1 :Text; > > > > >> > } > > > > >> > struct PairData { > > > > >> > name @0 :Text; > > > > >> > value @1 :Data; > > > > >> > } > > > > >> > enum Method { > > > > >> > GET @0; > > > > >> > ... > > > > >> > } > > > > >> > > > > > >> > struct HTTPReqCallReq { > > > > >> > id @0 :UInt32; > > > > >> > src_ip @1 :Data; > > > > >> > > > > > >> > method @2 :Method; > > > > >> > > > > > >> > path @3 :Text; > > > > >> > args @4 :List(Pair); > > > > >> > headers @5 :List(Pair); > > > > >> > > > > > >> > conf_token @6 :UInt32; > > > > >> > > > > > >> > extra_info @7 :List(PairData); > > > > >> > } > > > > >> > ``` > > > > >> > > > > > >> > Response > > > > >> > ``` > > > > >> > struct HTTPReqCallResp { > > > > >> > id @0 :UInt32; > > > > >> > > > > > >> > struct Stop { > > > > >> > status @0 :UInt16; > > > > >> > headers @1 :List(Pair); > > > > >> > body @2 :Data; > > > > >> > } > > > > >> > struct Rewrite { > > > > >> > path @0 :Text; > > > > >> > headers @1 :List(Pair); > > > > >> > # Note that args are modified in full. > > > > >> > # Either empty, meaning no args need to be moved > > > > >> > # or the entire modified args, not the incrementally > > changed > > > > >> parts > > > > >> > args @2 :List(Pair); > > > > >> > } > > > > >> > > > > > >> > # What needs to be done when the response is received action > > > > >> > action :union { > > > > >> > # Do nothing > > > > >> > continue @1 :Void; > > > > >> > # Equivalent to core.response.exit(status, body), > allowing > > > > >> > additional headers to be set > > > > >> > stop @2 :Stop; > > > > >> > # Rewrite the request > > > > >> > rewrite @3 :Rewrite; > > > > >> > } > > > > >> > } > > > > >> > ``` > > > > >> > > > > > >> > 2.4.4 Error handling > > > > >> > > > > > >> > Logging and returning 503 error codes > > > > >> > > > > > >> > 2.4.5 Environment variables > > > > >> > > > > > >> > APISIX configures the Plugin Runner with a number of environment > > > > >> > variables when it is started. > > > > >> > > > > > >> > APISIX_LISTEN_ADDRESS: the address that the Plugin Runner needs > to > > > > >> listen to > > > > >> > APISIX_CONF_EXPIRE_TIME: Plugin Runner needs to cache conf for > > > longer > > > > >> than this > > > > >> > > > > > > > > > > >
