getwtxt/getwtxt

/*
Copyright (c) 2019 Ben Morrison (gbmor)

This file is part of Getwtxt.

Getwtxt is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Getwtxt is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Getwtxt.  If not, see <https://www.gnu.org/licenses/>.
*/

package svc // import "git.sr.ht/~gbmor/getwtxt/svc"

import (
    "fmt"
    "log"
    "net/http"
    "time"

    "github.com/gorilla/handlers"
    "github.com/gorilla/mux"
)

// Start is the initialization function for getwtxt
func Start() {
    before := time.Now()
    initSvc()

    // StrictSlash(true) allows /api and /api/
    // to serve the same content without duplicating
    // handlers/paths
    index := mux.NewRouter().StrictSlash(true)
    setIndexRouting(index)

    // Serve the raw contents of this directory so users can
    // place miscellaneous files in it to use with the template.
    index.PathPrefix("/static").
        Methods("GET", "HEAD").
        Handler(http.StripPrefix("/static", http.FileServer(http.Dir(confObj.StaticDir))))

    api := index.PathPrefix("/api").Subrouter()
    setEndpointRouting(api)

    confObj.Mu.RLock()
    portnum := fmt.Sprintf(":%v", confObj.Port)
    confObj.Mu.RUnlock()

    server := newServer(portnum, index)

    log.Printf("*** Listening on %v\n", portnum)
    log.Printf("*** getwtxt %v Startup finished at %v, took %v\n\n", Vers, time.Now().Format(time.RFC3339), time.Since(before))
    errLog("", server.ListenAndServe())

    closeLog <- struct{}{}
    killTickers()
    killDB()
    close(dbChan)
    close(closeLog)
}

func newServer(port string, index *mux.Router) *http.Server {
    // handlers.CompressHandler gzips all responses.
    // ipMiddleware passes the request IP along.
    // Write/Read timeouts are self explanatory.
    return &http.Server{
        Handler:      handlers.CompressHandler(ipMiddleware(index)),
        Addr:         port,
        WriteTimeout: 15 * time.Second,
        ReadTimeout:  15 * time.Second,
    }
}

func setIndexRouting(index *mux.Router) {
    index.Path("/").
        Methods("GET", "HEAD").
        HandlerFunc(staticHandler)
    index.Path("/css").
        Methods("GET", "HEAD").
        HandlerFunc(staticHandler)
    index.Path("/api").
        Methods("GET", "HEAD").
        HandlerFunc(apiBaseHandler)
}

func setEndpointRouting(api *mux.Router) {
    api.Path("/admin/users").
        Methods("DELETE").
        HandlerFunc(handleUserDelete)

    // May add support for other formats later.
    // Making this future-proof.
    api.Path("/{format:(?:plain)}").
        Methods("GET", "HEAD").
        HandlerFunc(apiFormatHandler)

    // Non-standard API call to list *all* tweets
    // in a single request.
    api.Path("/{format:(?:plain)}/tweets/all").
        Methods("GET", "HEAD").
        HandlerFunc(apiAllTweetsHandler)

    // Specifying the endpoint with and without query information.
    // Will return 404 on empty queries otherwise.
    api.Path("/{format:(?:plain)}/{endpoint:(?:mentions|users|tweets|version)}").
        Methods("GET", "HEAD").
        HandlerFunc(apiEndpointHandler)
    api.Path("/{format:(?:plain)}/{endpoint:(?:mentions|users|tweets)}").
        Queries("url", "{url}", "q", "{query}", "page", "{[0-9]+}").
        Methods("GET", "HEAD").
        HandlerFunc(apiEndpointHandler)

    // This is for submitting new users. Both query variables must exist
    // in the request for this to match.
    api.Path("/{format:(?:plain)}/{endpoint:users}").
        Queries("url", "{url}", "nickname", "{nickname:[a-zA-Z0-9_-]+}").
        Methods("POST").
        HandlerFunc(apiEndpointPOSTHandler)
    // This is for submitting new users incorrectly
    // and letting the requester know about their error.
    api.Path("/{format:(?:plain)}/{endpoint:users}").
        Queries("url", "{url}").
        Methods("POST").
        HandlerFunc(apiEndpointPOSTHandler)
    // This is also for submitting new users incorrectly
    // and letting the requester know about their error.
    api.Path("/{format:(?:plain)}/{endpoint:users}").
        Queries("nickname", "{nickname:[a-zA-Z0-9_-]+}").
        Methods("POST").
        HandlerFunc(apiEndpointPOSTHandler)

    // Show all observed tags
    api.Path("/{format:(?:plain)}/tags").
        Methods("GET", "HEAD").
        HandlerFunc(apiTagsBaseHandler)
    // Show Nth page of all observed tags
    api.Path("/{format:(?:plain)}/tags").
        Queries("page", "{[0-9]+}").
        Methods("GET", "HEAD").
        HandlerFunc(apiTagsBaseHandler)

    // Requests statuses with a specific tag
    api.Path("/{format:(?:plain)}/tags/{tags:[a-zA-Z0-9_-]+}").
        Methods("GET", "HEAD").
        HandlerFunc(apiTagsHandler)
    // Requests Nth page of statuses with a specific tag
    api.Path("/{format:(?:plain)}/tags/{tags:[a-zA-Z0-9_-]+}").
        Queries("page", "{[0-9]+}").
        Methods("GET", "HEAD").
        HandlerFunc(apiTagsHandler)
}