Restrict cache results to 250 entries by default (#5049)

A query parameter `max_result_set_size` can be specified to set a
per-request limit, with `-1` meaning all values. If there were more
entries than the max size used for the request, an `incomplete` boolean
is set in the response.

internal/clientcache/cmd/search/search.go

@@ -7,6 +7,7 @@ import (
 	"context"
 	stderrors "errors"
 	"fmt"
+	"math"
 	"net/url"
 	"os"
 	"strings"
@@ -40,9 +41,10 @@ var (
 
 type SearchCommand struct {
 	*base.Command
-	flagQuery        string
-	flagResource     string
-	flagForceRefresh bool
+	flagQuery            string
+	flagResource         string
+	flagForceRefresh     bool
+	flagMaxResultSetSize int64
 }
 
 func (c *SearchCommand) Synopsis() string {
@@ -112,6 +114,12 @@ func (c *SearchCommand) Flags() *base.FlagSets {
 		Usage:      `Specifies the resource type to search over`,
 		Completion: complete.PredictSet(supportedResourceTypes...),
 	})
+	f.Int64Var(&base.Int64Var{
+		Name:       "max-result-set-size",
+		Target:     &c.flagMaxResultSetSize,
+		Usage:      `Specifies an override to the default maximum result set size. Set to -1 to disable the limit. 0 will use the default.`,
+		Completion: complete.PredictNothing,
+	})
 	f.BoolVar(&base.BoolVar{
 		Name:   "force-refresh",
 		Target: &c.flagForceRefresh,
@@ -148,6 +156,15 @@ func (c *SearchCommand) Run(args []string) int {
 		return base.CommandUserError
 	}
 
+	switch {
+	case c.flagMaxResultSetSize < -1:
+		c.PrintCliError(stderrors.New("Max result set size must be greater than or equal to -1"))
+		return base.CommandUserError
+	case c.flagMaxResultSetSize > math.MaxInt:
+		c.PrintCliError(stderrors.New(fmt.Sprintf("Max result set size must be less than or equal to the %v", math.MaxInt)))
+		return base.CommandUserError
+	}
+
 	resp, result, apiErr, err := c.Search(ctx)
 	if err != nil {
 		c.PrintCliError(err)
@@ -164,6 +181,9 @@ func (c *SearchCommand) Run(args []string) int {
 			return base.CommandCliError
 		}
 	default:
+		if result.Incomplete {
+			c.UI.Warn("The maximum result set size was reached and the search results are incomplete. Please narrow your search or adjust the -max-result-set-size parameter.")
+		}
 		switch {
 		case len(result.ResolvableAliases) > 0:
 			c.UI.Output(printAliasListTable(result.ResolvableAliases))
@@ -199,6 +219,9 @@ func (c *SearchCommand) Search(ctx context.Context) (*api.Response, *daemon.Sear
 		authTokenId:  strings.Join(tSlice[:2], "_"),
 		forceRefresh: c.flagForceRefresh,
 	}
+	if c.flagMaxResultSetSize != 0 {
+		tf.maxResultSetSize = int(c.flagMaxResultSetSize)
+	}
 	var opts []client.Option
 	if c.FlagOutputCurlString {
 		opts = append(opts, client.WithOutputCurlString())
@@ -230,6 +253,9 @@ func search(ctx context.Context, daemonPath string, fb filterBy, opt ...client.O
 	if fb.forceRefresh {
 		q.Add("force_refresh", "true")
 	}
+	if fb.maxResultSetSize != 0 {
+		q.Add("max_result_set_size", fmt.Sprintf("%d", fb.maxResultSetSize))
+	}
 	resp, err := c.Get(ctx, "/v1/search", q, opt...)
 	if err != nil {
 		return nil, nil, nil, fmt.Errorf("Error when sending request to the cache: %w.", err)
@@ -424,9 +450,10 @@ func printSessionListTable(items []*sessions.Session) string {
 }
 
 type filterBy struct {
-	flagFilter   string
-	flagQuery    string
-	authTokenId  string
-	resource     string
-	forceRefresh bool
+	flagFilter       string
+	flagQuery        string
+	authTokenId      string
+	resource         string
+	forceRefresh     bool
+	maxResultSetSize int
 }

internal/clientcache/internal/cache/consts.go

@@ -0,0 +1,17 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: BUSL-1.1
+
+/*
+Package cache contains the domain logic for the client cache.
+*/
+package cache
+
+const (
+	// defaultLimitedResultSetSize is the default number of results to
+	// return when limiting
+	defaultLimitedResultSetSize = 250
+
+	// unlimitedMaxResultSetSize is the value to use when we want to return all
+	// results
+	unlimitedMaxResultSetSize = -1
+)

internal/clientcache/internal/cache/options.go

@@ -4,6 +4,8 @@
 package cache
 
 import (
+	stderrors "errors"
+
 	"github.com/hashicorp/go-dbw"
 )
 
@@ -16,14 +18,16 @@ type options struct {
 	withTargetRetrievalFunc          TargetRetrievalFunc
 	withSessionRetrievalFunc         SessionRetrievalFunc
 	withIgnoreSearchStaleness        bool
+	withMaxResultSetSize             int
 }
 
 // Option - how options are passed as args
 type Option func(*options) error
 
 func getDefaultOptions() options {
 	return options{
-		withDbType: dbw.Sqlite,
+		withDbType:           dbw.Sqlite,
+		withMaxResultSetSize: defaultLimitedResultSetSize,
 	}
 }
 
@@ -94,3 +98,18 @@ func WithIgnoreSearchStaleness(b bool) Option {
 		return nil
 	}
 }
+
+// WithMaxResultSetSize provides an option for limiting the result set, e.g.
+// when no filter is provided on a list. A 0 does nothing (keeps the default).
+func WithMaxResultSetSize(with int) Option {
+	return func(o *options) error {
+		switch {
+		case with == 0:
+			return nil
+		case with < -1:
+			return stderrors.New("max result set size must be -1 or greater")
+		}
+		o.withMaxResultSetSize = with
+		return nil
+	}
+}

internal/clientcache/internal/cache/options_test.go

@@ -22,7 +22,8 @@ func Test_GetOpts(t *testing.T) {
 		opts, err := getOpts()
 		require.NoError(t, err)
 		testOpts := options{
-			withDbType: dbw.Sqlite,
+			withDbType:           dbw.Sqlite,
+			withMaxResultSetSize: defaultLimitedResultSetSize,
 		}
 		assert.Equal(t, opts, testOpts)
 	})
@@ -93,4 +94,16 @@ func Test_GetOpts(t *testing.T) {
 		testOpts.withIgnoreSearchStaleness = true
 		assert.Equal(t, opts, testOpts)
 	})
+	t.Run("withMaxResultSetSize", func(t *testing.T) {
+		opts, err := getOpts(WithMaxResultSetSize(defaultLimitedResultSetSize))
+		require.NoError(t, err)
+		testOpts := getDefaultOptions()
+		testOpts.withMaxResultSetSize = defaultLimitedResultSetSize
+		assert.Equal(t, opts, testOpts)
+		opts, err = getOpts(WithMaxResultSetSize(0))
+		require.Nil(t, err)
+		assert.Equal(t, opts, testOpts)
+		_, err = getOpts(WithMaxResultSetSize(-2))
+		require.Error(t, err)
+	})
 }