What is the "state" in server route handler?

linonetwo · March 27, 2022, 8:58am

exports.handler = function(request,response,state) {

I can see in the PUT example, we can get JSON body from the state? Why not get it from the request body?

	var title = $tw.utils.decodeURIComponentSafe(state.params[0]),
	fields = $tw.utils.parseJSONSafe(state.data);

So what is this state actually? Is there a doc for it, or where is the essential code of it? I can write a TS type for it if I understand it.

jeremyruston · March 27, 2022, 9:35am

Hi @linonetwo the “state” object should perhaps have been called “context” – it is a collection of properties that (mostly) relate to the state of the server, rather than the individual request.

I say “most”, because as you can see from the code, there is actually a bunch of properties that are derived from the current request (eg urlInfo), which should perhaps have been a separate object.

github.com

Jermolene/TiddlyWiki5/blob/e84acf97dea58b7b3e53fa0107f14b75f151ba6d/core/modules/server/server.js#L250-L267

    
      
          	var state = {};
          	state.wiki = options.wiki || self.wiki;
          	state.boot = options.boot || self.boot;
          	state.server = self;
          	state.urlInfo = url.parse(request.url);
          	state.queryParameters = querystring.parse(state.urlInfo.query);
          	state.pathPrefix = options.pathPrefix || this.get("path-prefix") || "";
          	state.sendResponse = sendResponse.bind(self,request,response);
          	// Get the principals authorized to access this resource
          	state.authorizationType = options.authorizationType || this.methodMappings[request.method] || "readers";
          	// Check for the CSRF header if this is a write
          	if(!this.csrfDisable && state.authorizationType === "writers" && request.headers["x-requested-with"] !== "TiddlyWiki") {
          		response.writeHead(403,"'X-Requested-With' header required to login to '" + this.servername + "'");
          		response.end();
          		return;
          	}
          	// Check whether anonymous access is granted
          	state.allowAnon = this.isAuthorized(state.authorizationType,null);

linonetwo · March 27, 2022, 12:42pm

Thank you Jeremy, I think context may be better, most server frameworks use it.

I can start using context in my new plugin…