Publish ITWorx Pulse source

internal/processapi/handler.go

@@ -0,0 +1,67 @@
+package processapi
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/itworx/pulse/internal/auth"
+	"github.com/itworx/pulse/internal/problem"
+	"github.com/itworx/pulse/internal/process"
+)
+
+type Handler struct {
+	Provider interface {
+		Snapshot(context.Context) (process.Snapshot, error)
+	}
+	Limits process.Limits
+}
+
+func (h Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet || r.URL.Path != "/api/v1/processes" {
+		http.NotFound(w, r)
+		return
+	}
+	if _, ok := auth.PrincipalFromContext(r.Context()); !ok {
+		problem.Write(w, r, http.StatusUnauthorized, "UNAUTHORIZED", "Authentication required", "Authentication is required to read processes.", nil)
+		return
+	}
+	limit := 50
+	if value := r.URL.Query().Get("limit"); value != "" {
+		parsed, err := strconv.Atoi(value)
+		if err != nil {
+			problem.Write(w, r, http.StatusBadRequest, "PROCESS_LIMIT_INVALID", "Invalid process limit", "The process page limit is invalid.", nil)
+			return
+		}
+		limit = parsed
+	}
+	mode := process.SortMode(r.URL.Query().Get("sort"))
+	if mode == "" {
+		mode = process.SortCPU
+	}
+	var snapshot process.Snapshot
+	var err error
+	if h.Provider == nil {
+		snapshot = process.UnknownSnapshot(time.Now().UTC(), "process", "agent", "source_unavailable")
+	} else {
+		snapshot, err = h.Provider.Snapshot(r.Context())
+	}
+	if err != nil {
+		if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
+			return
+		}
+		problem.Write(w, r, http.StatusServiceUnavailable, "PROCESS_UNAVAILABLE", "Processgegevens niet beschikbaar", "De procesgegevens konden niet worden gelezen.", nil)
+		return
+	}
+	page, err := process.FilteredPage(snapshot, mode, limit, r.URL.Query().Get("after"), h.Limits, r.URL.Query().Get("q"), r.URL.Query().Get("container"))
+	if err != nil {
+		problem.Write(w, r, http.StatusBadRequest, "PROCESS_QUERY_INVALID", "Invalid process query", "The process sort, cursor or limit is invalid.", nil)
+		return
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.Header().Set("Cache-Control", "private, max-age=5")
+	_ = json.NewEncoder(w).Encode(page)
+}