From f2180fbc2fa414f044a2100e3bfabaf3a542e977 Mon Sep 17 00:00:00 2001
From: ionutboangiu <ionut.boangiu@itsyscom.com>
Date: Wed, 30 Mar 2022 16:56:05 +0300
Subject: [PATCH] Implement pagination for rates

---
 apis/rates.go             | 43 ++++++++++++++++++++++++++++++++-----
 config/config_defaults.go | 23 +++++++++++++++++++-
 config/ratescfg.go        | 45 +++++++++++++++++++++++++++++++++++++++
 utils/consts.go           |  3 +++
 4 files changed, 108 insertions(+), 6 deletions(-)

diff --git a/apis/rates.go b/apis/rates.go
index dc741104d..33c00a1a5 100644
--- a/apis/rates.go
+++ b/apis/rates.go
@@ -19,6 +19,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>
 package apis
 
 import (
+	"sort"
 	"time"
 
 	"github.com/cgrates/birpc/context"
@@ -28,7 +29,7 @@ import (
 )
 
 // GetRateProfile returns a Rate Profile based on tenant and id
-func (admS *AdminSv1) GetRateProfile(ctx *context.Context, arg *utils.TenantIDWithAPIOpts, reply *utils.RateProfile) error {
+func (admS *AdminSv1) GetRateProfile(ctx *context.Context, arg *utils.TenantIDWithAPIOpts, reply *utils.RateProfile) (err error) {
 	if missing := utils.MissingStructFields(arg, []string{utils.ID}); len(missing) != 0 { //Params missing
 		return utils.NewErrMandatoryIeMissing(missing...)
 	}
@@ -36,16 +37,48 @@ func (admS *AdminSv1) GetRateProfile(ctx *context.Context, arg *utils.TenantIDWi
 	if tnt == utils.EmptyString {
 		tnt = admS.cfg.GeneralCfg().DefaultTenant
 	}
-	rPrf, err := admS.dm.GetRateProfile(ctx, tnt, arg.ID, true, true, utils.NonTransactional)
+	var rPrf *utils.RateProfile
+	rPrf, err = admS.dm.GetRateProfile(ctx, tnt, arg.ID, true, true, utils.NonTransactional)
 	if err != nil {
 		if err.Error() != utils.ErrNotFound.Error() {
 			err = utils.NewErrServerError(err)
 		}
-		return err
+		return
 	}
-
+	rateIDs := make([]string, len(rPrf.Rates))
+	i := 0
+	for rateID := range rPrf.Rates {
+		rateIDs[i] = rateID
+		i++
+	}
+	sort.Strings(rateIDs)
+	var limit, offset, maxItems int
+	// if limit, err = engine.GetIntOpts(ctx, tnt, nil, nil, admS.cfg.RateSCfg().Opts.Limit,
+	// 	config.RatesLimitDftOpt, utils.OptsRatesLimit); err != nil {
+	// 	return
+	// }
+	// if offset, err = engine.GetIntOpts(ctx, tnt, nil, nil, admS.cfg.RateSCfg().Opts.Offset,
+	// 	config.RatesLimitDftOpt, utils.OptsRatesOffset); err != nil {
+	// 	return
+	// }
+	// if maxItems, err = engine.GetIntOpts(ctx, tnt, nil, nil, admS.cfg.RateSCfg().Opts.Limit,
+	// 	config.RatesLimitDftOpt, utils.OptsRatesMaxItems); err != nil {
+	// 	return
+	// }
+	if limit, offset, maxItems, err = utils.GetPaginateOpts(arg.APIOpts); err != nil {
+		return
+	}
+	rateIDs, err = utils.Paginate(rateIDs, limit, offset, maxItems)
+	if err != nil {
+		return
+	}
+	paginatedRates := make(map[string]*utils.Rate)
+	for _, rateID := range rateIDs {
+		paginatedRates[rateID] = rPrf.Rates[rateID]
+	}
+	rPrf.Rates = paginatedRates
 	*reply = *rPrf
-	return nil
+	return
 }
 
 // GetRateProfile returns the rates of a profile based on their profile. Those rates will be returned back by matching a prefix.
diff --git a/config/config_defaults.go b/config/config_defaults.go
index b60483e81..5a45319ac 100644
--- a/config/config_defaults.go
+++ b/config/config_defaults.go
@@ -1564,7 +1564,28 @@ const CGRATES_CFG_JSON = `
 			// 	"FilterIDs": [],
 			// 	"Value": false,
 			// },
-		],									
+		],		
+		// "*limit": [						
+		// 	{
+		// 		"Tenant": "*any",
+		// 		"FilterIDs": [],
+		// 		"Value": 1,
+		// 	},
+		// ],
+		// "*offset": [						
+		// 	{
+		// 		"Tenant": "*any",
+		// 		"FilterIDs": [],
+		// 		"Value": 1,
+		// 	},
+		// ],
+		// "*maxItems": [						
+		// 	{
+		// 		"Tenant": "*any",
+		// 		"FilterIDs": [],
+		// 		"Value": 1,
+		// 	},
+		// ],							
 	},
 },
 
diff --git a/config/ratescfg.go b/config/ratescfg.go
index e198c7548..db760a289 100644
--- a/config/ratescfg.go
+++ b/config/ratescfg.go
@@ -35,6 +35,9 @@ var (
 const (
 	RatesStartTimeDftOpt            = "*now"
 	RatesProfileIgnoreFiltersDftOpt = false
+	RatesLimitDftOpt                = 0
+	RatesOffsetDftOpt               = 0
+	RatesMaxItemsDftOpt             = 0
 )
 
 type RatesOpts struct {
@@ -43,6 +46,9 @@ type RatesOpts struct {
 	Usage                []*utils.DynamicDecimalBigOpt
 	IntervalStart        []*utils.DynamicDecimalBigOpt
 	ProfileIgnoreFilters []*utils.DynamicBoolOpt
+	Limit                []*utils.DynamicIntOpt
+	Offset               []*utils.DynamicIntOpt
+	MaxItems             []*utils.DynamicIntOpt
 }
 
 // RateSCfg the rates config section
@@ -102,6 +108,15 @@ func (rateOpts *RatesOpts) loadFromJSONCfg(jsnCfg *RatesOptsJson) (err error) {
 	if jsnCfg.ProfileIgnoreFilters != nil {
 		rateOpts.ProfileIgnoreFilters = append(rateOpts.ProfileIgnoreFilters, jsnCfg.ProfileIgnoreFilters...)
 	}
+	if jsnCfg.Limit != nil {
+		rateOpts.Limit = append(rateOpts.Limit, jsnCfg.Limit...)
+	}
+	if jsnCfg.Offset != nil {
+		rateOpts.Offset = append(rateOpts.Offset, jsnCfg.Offset...)
+	}
+	if jsnCfg.MaxItems != nil {
+		rateOpts.MaxItems = append(rateOpts.MaxItems, jsnCfg.MaxItems...)
+	}
 	return
 }
 
@@ -172,6 +187,9 @@ func (rCfg RateSCfg) AsMapInterface(string) interface{} {
 		utils.MetaUsage:                rCfg.Opts.Usage,
 		utils.MetaIntervalStartCfg:     rCfg.Opts.IntervalStart,
 		utils.MetaProfileIgnoreFilters: rCfg.Opts.ProfileIgnoreFilters,
+		utils.MetaLimitCfg:             rCfg.Opts.Limit,
+		utils.MetaOffsetCfg:            rCfg.Opts.Offset,
+		utils.MetaMaxItemsCfg:          rCfg.Opts.MaxItems,
 	}
 	mp := map[string]interface{}{
 		utils.EnabledCfg:            rCfg.Enabled,
@@ -239,12 +257,27 @@ func (rateOpts *RatesOpts) Clone() *RatesOpts {
 	if rateOpts.ProfileIgnoreFilters != nil {
 		profileIgnoreFilters = utils.CloneDynamicBoolOpt(rateOpts.ProfileIgnoreFilters)
 	}
+	var limit []*utils.DynamicIntOpt
+	if rateOpts.Limit != nil {
+		limit = utils.CloneDynamicIntOpt(rateOpts.Limit)
+	}
+	var offset []*utils.DynamicIntOpt
+	if rateOpts.Offset != nil {
+		offset = utils.CloneDynamicIntOpt(rateOpts.Offset)
+	}
+	var maxItems []*utils.DynamicIntOpt
+	if rateOpts.MaxItems != nil {
+		maxItems = utils.CloneDynamicIntOpt(rateOpts.MaxItems)
+	}
 	return &RatesOpts{
 		ProfileIDs:           ratePrfIDs,
 		StartTime:            startTime,
 		Usage:                usage,
 		IntervalStart:        intervalStart,
 		ProfileIgnoreFilters: profileIgnoreFilters,
+		Limit:                limit,
+		Offset:               offset,
+		MaxItems:             maxItems,
 	}
 }
 
@@ -298,6 +331,9 @@ type RatesOptsJson struct {
 	Usage                []*utils.DynamicStringOpt      `json:"*usage"`
 	IntervalStart        []*utils.DynamicStringOpt      `json:"*intervalStart"`
 	ProfileIgnoreFilters []*utils.DynamicBoolOpt        `json:"*profileIgnoreFilters"`
+	Limit                []*utils.DynamicIntOpt         `json:"*limit"`
+	Offset               []*utils.DynamicIntOpt         `json:"*offset"`
+	MaxItems             []*utils.DynamicIntOpt         `json:"*maxItems"`
 }
 
 type RateSJsonCfg struct {
@@ -339,6 +375,15 @@ func diffRatesOptsJsonCfg(d *RatesOptsJson, v1, v2 *RatesOpts) *RatesOptsJson {
 	if !utils.DynamicBoolOptEqual(v1.ProfileIgnoreFilters, v2.ProfileIgnoreFilters) {
 		d.ProfileIgnoreFilters = v2.ProfileIgnoreFilters
 	}
+	if !utils.DynamicIntOptEqual(v1.Limit, v2.Limit) {
+		d.Limit = v2.Limit
+	}
+	if !utils.DynamicIntOptEqual(v1.Offset, v2.Offset) {
+		d.Offset = v2.Offset
+	}
+	if !utils.DynamicIntOptEqual(v1.MaxItems, v2.MaxItems) {
+		d.MaxItems = v2.MaxItems
+	}
 	return d
 }
 
diff --git a/utils/consts.go b/utils/consts.go
index 619729285..0266db7f1 100644
--- a/utils/consts.go
+++ b/utils/consts.go
@@ -2281,6 +2281,9 @@ const (
 	OptsRatesStartTime     = "*rtsStartTime"
 	OptsRatesUsage         = "*rtsUsage"
 	OptsRatesIntervalStart = "*rtsIntervalStart"
+	OptsRatesLimit         = "*rtsLimit"
+	OptsRatesOffset        = "*rtsOffset"
+	OptsRatesMaxItems      = "*rtsMaxItems"
 
 	// Resources
 	OptsResourcesUnits    = "*rsUnits"