feat: Implement unified pagination and add template versions support (#1308)

* feat: Implement pagination for template versions

* feat: Use unified pagination between users and template versions

* Sync codepaths between users and template versions

* Create requestOption type in codersdk and add test

* Fix created_at edge case for pagination cursor in queries

* feat: Add support for json omitempty and embedded structs in apitypings (#1318)

* Add scripts/apitypings/main.go to Makefile

coderd/pagination.go

@@ -0,0 +1,57 @@
+package coderd
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+
+	"github.com/google/uuid"
+
+	"github.com/coder/coder/coderd/httpapi"
+	"github.com/coder/coder/codersdk"
+)
+
+// parsePagination extracts pagination query params from the http request.
+// If an error is encountered, the error is written to w and ok is set to false.
+func parsePagination(w http.ResponseWriter, r *http.Request) (p codersdk.Pagination, ok bool) {
+	var (
+		afterID = uuid.Nil
+		limit   = -1 // Default to no limit and return all results.
+		offset  = 0
+	)
+
+	var err error
+	if s := r.URL.Query().Get("after_id"); s != "" {
+		afterID, err = uuid.Parse(r.URL.Query().Get("after_id"))
+		if err != nil {
+			httpapi.Write(w, http.StatusBadRequest, httpapi.Response{
+				Message: fmt.Sprintf("after_id must be a valid uuid: %s", err.Error()),
+			})
+			return p, false
+		}
+	}
+	if s := r.URL.Query().Get("limit"); s != "" {
+		limit, err = strconv.Atoi(s)
+		if err != nil {
+			httpapi.Write(w, http.StatusBadRequest, httpapi.Response{
+				Message: fmt.Sprintf("limit must be an integer: %s", err.Error()),
+			})
+			return p, false
+		}
+	}
+	if s := r.URL.Query().Get("offset"); s != "" {
+		offset, err = strconv.Atoi(s)
+		if err != nil {
+			httpapi.Write(w, http.StatusBadRequest, httpapi.Response{
+				Message: fmt.Sprintf("offset must be an integer: %s", err.Error()),
+			})
+			return p, false
+		}
+	}
+
+	return codersdk.Pagination{
+		AfterID: afterID,
+		Limit:   limit,
+		Offset:  offset,
+	}, true
+}