Extract repository helpers to pkg/rh package

compose/internal/repository/record.go

@@ -11,8 +11,8 @@ import (
 	"gopkg.in/Masterminds/squirrel.v1"
 
 	"github.com/cortezaproject/corteza-server/compose/internal/repository/ql"
-
 	"github.com/cortezaproject/corteza-server/compose/types"
+	"github.com/cortezaproject/corteza-server/pkg/rh"
 )
 
 type (
@@ -117,7 +117,7 @@ func (r record) Report(module *types.Module, metrics, dimensions, filter string)
 func (r record) Find(module *types.Module, filter types.RecordFilter) (set types.RecordSet, f types.RecordFilter, err error) {
 	var query squirrel.SelectBuilder
 	f = filter
-	f.PerPage = normalizePerPage(f.PerPage, 5, 100, 50)
+	f.PerPage = rh.NormalizePerPage(f.PerPage, 5, 100, 50)
 
 	query, err = r.buildQuery(module, filter)
 	if err != nil {

compose/internal/repository/repository.go

@@ -3,12 +3,11 @@ package repository
 import (
 	"context"
 
-	"github.com/lann/builder"
-	"github.com/pkg/errors"
 	"github.com/titpetric/factory"
 	"gopkg.in/Masterminds/squirrel.v1"
 
 	"github.com/cortezaproject/corteza-server/internal/auth"
+	"github.com/cortezaproject/corteza-server/pkg/rh"
 )
 
 type (
@@ -51,82 +50,23 @@ func (r *repository) db() *factory.DB {
 
 // Fetches single row from table
 func (r repository) fetchOne(one interface{}, q squirrel.SelectBuilder) (err error) {
-	var (
-		sql  string
-		args []interface{}
-	)
-
-	if sql, args, err = q.ToSql(); err != nil {
-		return
-	}
-
-	if err = r.db().Get(one, sql, args...); err != nil {
-		return
-	}
-
-	return
+	return rh.FetchOne(r.db(), q, one)
 }
 
 // Counts all rows that match conditions from given query builder
 func (r repository) count(q squirrel.SelectBuilder) (uint, error) {
-	var (
-		count uint
-		cq    = q.Column("COUNT(*)")
-	)
-
-	// Remove order-bys for counting
-	cq = builder.Delete(cq, "OrderBys").(squirrel.SelectBuilder)
-
-	if sqlSelect, argsSelect, err := cq.ToSql(); err != nil {
-		return 0, err
-	} else {
-		if err := r.db().Get(&count, sqlSelect, argsSelect...); err != nil {
-			return 0, err
-		}
-	}
-
-	return count, nil
+	return rh.Count(r.db(), q)
 }
 
 // Fetches paged rows
 func (r repository) fetchPaged(set interface{}, q squirrel.SelectBuilder, page, perPage uint) error {
-	if perPage > 0 {
-		q = q.Limit(uint64(perPage))
-	}
-
-	if page > 0 {
-		q = q.Offset(uint64(page * perPage))
-	}
-
-	if sqlSelect, argsSelect, err := q.ToSql(); err != nil {
-		return err
-	} else {
-		return r.db().Select(set, sqlSelect, argsSelect...)
-	}
+	return rh.FetchPaged(r.db(), q, page, perPage, set)
 }
 
 func normalizePerPage(val, min, max, def uint) uint {
-	if val == 0 {
-		return def
-	}
-
-	if max > 0 && val > max {
-		return max
-	}
-
-	if min > 0 && val < min {
-		return min
-	}
-
-	return val
+	return rh.NormalizePerPage(val, min, max, def)
 }
 
 func isFound(err error, valid bool, nerr error) error {
-	if err != nil {
-		return errors.WithStack(err)
-	} else if !valid {
-		return errors.WithStack(nerr)
-	}
-
-	return nil
+	return rh.IsFound(err, valid, nerr)
 }

pkg/rh/README.md

@@ -0,0 +1,4 @@
+# (rh) Repository Helpers
+
+Package name is short an abbreviated to avoid 
+colliding with per-service repository package names.

pkg/rh/helpers.go

@@ -0,0 +1,99 @@
+package rh
+
+import (
+	"github.com/lann/builder"
+	"github.com/pkg/errors"
+	"github.com/titpetric/factory"
+	"gopkg.in/Masterminds/squirrel.v1"
+)
+
+// FetchOne fetches single row from table
+func FetchOne(db *factory.DB, q squirrel.SelectBuilder, one interface{}) (err error) {
+	var (
+		sql  string
+		args []interface{}
+	)
+
+	if sql, args, err = q.ToSql(); err != nil {
+		return
+	}
+
+	if err = db.Get(one, sql, args...); err != nil {
+		return
+	}
+
+	return
+}
+
+// Count counts all rows that match conditions from given query builder
+func Count(db *factory.DB, q squirrel.SelectBuilder) (count uint, err error) {
+	// Remove order-bys for counting
+	q = builder.Delete(q, "OrderBys").(squirrel.SelectBuilder)
+
+	// Replace columns
+	q = builder.Delete(q, "Columns").(squirrel.SelectBuilder).Column("COUNT(*)")
+
+	if sqlSelect, argsSelect, err := q.ToSql(); err != nil {
+		return 0, err
+	} else {
+		if err := db.Get(&count, sqlSelect, argsSelect...); err != nil {
+			return 0, err
+		}
+	}
+
+	return count, nil
+}
+
+// FetchPaged fetches paged rows
+func FetchPaged(db *factory.DB, q squirrel.SelectBuilder, page, perPage uint, set interface{}) error {
+	if perPage > 0 {
+		q = q.Limit(uint64(perPage))
+	}
+
+	if page > 0 {
+		q = q.Offset(uint64(page * perPage))
+	}
+
+	if sqlSelect, argsSelect, err := q.ToSql(); err != nil {
+		return err
+	} else {
+		return db.Select(set, sqlSelect, argsSelect...)
+	}
+}
+
+// FetchPaged fetches paged rows
+func FetchAll(db *factory.DB, q squirrel.SelectBuilder, set interface{}) error {
+	if sqlSelect, argsSelect, err := q.ToSql(); err != nil {
+		return err
+	} else {
+		return db.Select(set, sqlSelect, argsSelect...)
+	}
+}
+
+// NormalizePerPage normalize page number
+func NormalizePerPage(val, min, max, def uint) uint {
+	if val == 0 {
+		return def
+	}
+
+	if max > 0 && val > max {
+		return max
+	}
+
+	if min > 0 && val < min {
+		return min
+	}
+
+	return val
+}
+
+// IsFound helps with one-row results
+func IsFound(err error, valid bool, nerr error) error {
+	if err != nil {
+		return errors.WithStack(err)
+	} else if !valid {
+		return errors.WithStack(nerr)
+	}
+
+	return nil
+}

pkg/rh/paging.go

@@ -0,0 +1,30 @@
+package rh
+
+const (
+	PER_PAGE_DEFAULT uint = 50
+	PER_PAGE_MAX          = 200
+	PER_PAGE_MIN          = 10
+)
+
+type (
+	PageFilter struct {
+		Page    uint `json:"page"`
+		PerPage uint `json:"perPage"`
+		Count   uint `json:"count"`
+	}
+)
+
+func Paging(page, perPage uint) PageFilter {
+	return PageFilter{
+		Page:    page,
+		PerPage: perPage,
+	}
+}
+
+func (pf *PageFilter) NormalizePerPage(min, max, def uint) {
+	pf.PerPage = NormalizePerPage(pf.PerPage, min, max, def)
+}
+
+func (pf *PageFilter) NormalizePerPageWithDefaults() {
+	pf.PerPage = NormalizePerPage(pf.PerPage, PER_PAGE_MIN, PER_PAGE_MAX, PER_PAGE_DEFAULT)
+}