Go SDK for implementing Google API Improvement Proposals (AIP).

See https://aip.dev for the full AIP documentation.

$ go get -u go.einride.tech/aip

• Use pagination.PageToken to implement offset-based pagination.

  package examplelibrary
  
  import (
  	"context"
  
  	"go.einride.tech/aip/pagination"
  	"google.golang.org/genproto/googleapis/example/library/v1"
  	"google.golang.org/grpc/codes"
  	"google.golang.org/grpc/status"
  )
  
  func (s *Server) ListShelves(
  	ctx context.Context,
  	request *library.ListShelvesRequest,
  ) (*library.ListShelvesResponse, error) {
  	// Handle request constraints.
  	const (
  		maxPageSize     = 1000
  		defaultPageSize = 100
  	)
  	switch {
  	case request.PageSize < 0:
  		return nil, status.Errorf(codes.InvalidArgument, "page size is negative")
  	case request.PageSize == 0:
  		request.PageSize = defaultPageSize
  	case request.PageSize > maxPageSize:
  		request.PageSize = maxPageSize
  	}
  	// Use pagination.PageToken for offset-based page tokens.
  	pageToken, err := pagination.ParsePageToken(request)
  	if err != nil {
  		return nil, status.Errorf(codes.InvalidArgument, "invalid page token")
  	}
  	// Query the storage.
  	result, err := s.Storage.ListShelves(ctx, &ListShelvesQuery{
  		Offset:   pageToken.Offset,
  		PageSize: request.GetPageSize(),
  	})
  	if err != nil {
  		return nil, err
  	}
  	// Build the response.
  	response := &library.ListShelvesResponse{
  		Shelves: result.Shelves,
  	}
  	// Set the next page token.
  	if result.HasNextPage {
  		response.NextPageToken = pageToken.Next(request).String()
  	}
  	// Respond.
  	return response, nil
  }