gotelem/http.go
2024-02-29 13:13:25 -06:00

222 lines
6 KiB
Go

package gotelem
// this file defines the HTTP handlers and routes.
import (
"encoding/json"
"fmt"
"net/http"
"time"
"log/slog"
"github.com/go-chi/chi/v5"
"github.com/go-chi/chi/v5/middleware"
"github.com/google/uuid"
"github.com/kschamplin/gotelem/internal/db"
"github.com/kschamplin/gotelem/skylab"
"nhooyr.io/websocket"
"nhooyr.io/websocket/wsjson"
)
func TelemRouter(log *slog.Logger, broker *Broker, db *db.TelemDb) http.Handler {
r := chi.NewRouter()
r.Use(middleware.RequestID)
r.Use(middleware.RealIP)
r.Use(middleware.Logger) // TODO: integrate with slog instead of go default logger.
r.Use(middleware.Recoverer)
// heartbeat request.
r.Get("/ping", func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("pong"))
})
r.Mount("/api/v1", apiV1(broker, db))
// To future residents - you can add new API calls/systems in /api/v2
// Don't break anything in api v1! keep legacy code working!
return r
}
// define API version 1 routes.
func apiV1(broker *Broker, db *db.TelemDb) chi.Router {
r := chi.NewRouter()
// this API only accepts JSON.
r.Use(middleware.AllowContentType("application/json"))
// no caching - always get the latest data.
// TODO: add a smart short expiry cache for queries that take a while.
r.Use(middleware.NoCache)
r.Get("/schema", func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
// return the Skylab JSON definitions
w.Write([]byte(skylab.SkylabDefinitions))
})
r.Route("/packets", func(r chi.Router) {
r.Get("/subscribe", apiV1PacketSubscribe(broker, db))
r.Post("/", func(w http.ResponseWriter, r *http.Request) {
var pkgs []skylab.BusEvent
decoder := json.NewDecoder(r.Body)
if err := decoder.Decode(&pkgs); err != nil {
w.WriteHeader(http.StatusTeapot)
return
}
// we have a list of packets now. let's commit them.
db.AddEvents(pkgs...)
})
r.Get("/", func(w http.ResponseWriter, r *http.Request) {
// this should use http query params to return a list of packets.
})
// this is to get a single field
r.Get("/{name:[a-z_]+}/{field:[a-z_]+}", apiV1GetValues(db))
})
// records are driving segments/runs.
r.Route("/records", func(r chi.Router) {
r.Get("/", apiV1GetRecords(db)) // get all runs
r.Get("/active", apiV1GetActiveRecord(db)) // get current run (no end time)
r.Post("/", apiV1StartRecord(db)) // create a new run (with note). Ends active run if any, and creates new active run (no end time)
r.Get("/{id}", apiV1GetRecord(db)) // get details on a specific run
r.Put("/{id}", apiV1UpdateRecord(db)) // update a specific run. Can only be used to add notes/metadata, and not to change time/id.
})
r.Get("/stats", func(w http.ResponseWriter, r *http.Request) {
}) // v1 api stats (calls, clients, xbee connected, meta health ok)
return r
}
// apiV1Subscriber is a websocket session for the v1 api.
type apiV1Subscriber struct {
nameFilter []string // names of packets we care about.
}
// this is a websocket stream.
func apiV1PacketSubscribe(broker *Broker, db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
conn_id := r.RemoteAddr + uuid.New().String()
sub, err := broker.Subscribe(conn_id)
if err != nil {
w.WriteHeader(http.StatusInternalServerError)
fmt.Fprintf(w, "error subscribing: %s", err)
return
}
defer broker.Unsubscribe(conn_id)
// attempt to upgrade.
c, err := websocket.Accept(w, r, nil)
c.Ping(r.Context())
if err != nil {
// TODO: is this the correct option?
w.WriteHeader(http.StatusInternalServerError)
fmt.Fprintf(w, "error ws handshake: %s", err)
return
}
// TODO: use K/V with session token?
sess := &apiV1Subscriber{}
for {
select {
case <-r.Context().Done():
return
case msgIn := <-sub:
if len(sess.nameFilter) == 0 {
// send it.
wsjson.Write(r.Context(), c, msgIn)
}
for _, name := range sess.nameFilter {
if name == msgIn.Name {
// send it
wsjson.Write(r.Context(), c, msgIn)
break
}
}
}
}
}
}
// apiV1GetValues is a function that creates a handler for
// getting the specific value from a packet.
// this is useful for OpenMCT or other viewer APIs
func apiV1GetValues(db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
var err error
// we need a start and end time. If none is provided,
// we use unix epoch as start, and now + 1 day as end.
start := time.Unix(0, 0)
startString := r.URL.Query().Get("start")
if startString != "" {
start, err = time.Parse(time.RFC3339, startString)
if err != nil {
http.Error(w, "error getting values", http.StatusInternalServerError)
return
}
}
end := time.Now().Add(1 * time.Hour)
endParam := r.URL.Query().Get("start")
if endParam != "" {
end, err = time.Parse(time.RFC3339, endParam)
if err != nil {
http.Error(w, "error getting values", http.StatusInternalServerError)
return
}
}
name := chi.URLParam(r, "name")
field := chi.URLParam(r, "field")
// TODO: add limit and pagination
res, err := db.GetValues(r.Context(), name, field, start, end)
if err != nil {
// 500 server error:
http.Error(w, "error getting values", http.StatusInternalServerError)
return
}
b, err := json.Marshal(res)
if err != nil {
http.Error(w, "error getting values", http.StatusInternalServerError)
return
}
w.Write(b)
}
}
// TODO: rename. record is not a clear name. Runs? drives? segments?
func apiV1GetRecords(db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
}
}
func apiV1GetActiveRecord(db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
}
}
func apiV1StartRecord(db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {}
}
func apiV1GetRecord(db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {}
}
func apiV1UpdateRecord(db *db.TelemDb) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {}
}