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Move gid and page pkg

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Signed-off-by: gearnode <bryan@frimin.fr>
This commit is contained in:
gearnode
2025-02-02 11:13:16 -08:00
parent d64350eaea
commit 3fcf5e437c
31 changed files with 86 additions and 86 deletions
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112
pkg/page/cursor.go Normal file
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// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
package page
import (
"fmt"
"github.com/jackc/pgx/v5"
)
type (
Cursor struct {
Size int
Key *CursorKey
Position Position
}
Position int8
)
const (
DefaultCursorSize = 25
Tail Position = iota
Head
)
func (p Position) ToDirection() string {
switch p {
case Tail:
return "ASC"
case Head:
return "DESC"
default:
panic(fmt.Errorf("unknown direction: %d", p))
}
}
func NewCursor(size int, from *CursorKey, pos Position) *Cursor {
if size == 0 {
size = DefaultCursorSize
}
return &Cursor{
Size: size,
Key: from,
Position: pos,
}
}
func (c *Cursor) SQLFragment() string {
return `
CASE
WHEN @cursor_order = 'DESC' AND @cursor_from_id::TEXT IS NOT NULL THEN (
(created_at <= @cursor_from_ts) AND NOT (created_at = @cursor_from_ts AND id > @cursor_from_id)
)
WHEN @cursor_order = 'ASC' AND @cursor_from_id::TEXT IS NOT NULL THEN (
(created_at >= @cursor_from_ts) AND NOT (created_at = @cursor_from_ts AND id < @cursor_from_id)
)
ELSE TRUE
END
ORDER BY
CASE
WHEN @cursor_order = 'ASC' THEN created_at
END ASC,
CASE
WHEN @cursor_order = 'ASC' THEN id
END ASC,
CASE
WHEN @cursor_order = 'DESC' THEN created_at
END DESC,
CASE
WHEN @cursor_order = 'DESC' THEN id
END DESC
LIMIT @cursor_limit
`
}
func (c *Cursor) SQLArguments() pgx.NamedArgs {
var size = c.Size
if c.Key == nil {
size += 1
} else {
size += 2
}
arguments := pgx.NamedArgs{
"cursor_order": c.Position.ToDirection(),
"cursor_limit": size,
"cursor_from_id": nil,
"cursor_from_ts": nil,
}
if c.Key != nil {
arguments["cursor_from_id"] = c.Key.ID()
arguments["cursor_from_ts"] = c.Key.Timestamp()
}
return arguments
}

124
pkg/page/cursorkey.go Normal file
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// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
package page
import (
"encoding/base64"
"encoding/binary"
"errors"
"time"
"go.gearno.de/crypto/uuid"
)
type (
CursorKey [byteLength]byte
)
var (
CursorKeyNil CursorKey
ErrInvalidFormat = errors.New("invalid format")
)
const (
byteLength = 24
)
func ParseCursorKey(s string) (CursorKey, error) {
b, err := base64.RawURLEncoding.DecodeString(s)
if err != nil {
return CursorKeyNil, ErrInvalidFormat
}
ck, err := CursorKeyFromBytes(b)
if err != nil {
return CursorKeyNil, ErrInvalidFormat
}
return ck, nil
}
func CursorKeyFromBytes(b []byte) (CursorKey, error) {
var ck CursorKey
if len(b) != byteLength {
return CursorKeyNil, ErrInvalidFormat
}
copy(ck[:], b)
return ck, nil
}
func NewCursorKey(id uuid.UUID, t time.Time) CursorKey {
var cursorKey CursorKey
copy(cursorKey[:16], id[:])
_ = binary.PutVarint(cursorKey[16:], t.UnixMicro())
return cursorKey
}
func (ck CursorKey) Bytes() []byte {
return ck[:]
}
func (ck CursorKey) String() string {
return base64.RawURLEncoding.EncodeToString(ck.Bytes())
}
func (ck CursorKey) Timestamp() time.Time {
unixMicro, _ := binary.Varint(ck[16:])
seconds := unixMicro / 1e6
nanoseconds := (unixMicro % 1e6) * 1e3
return time.Unix(seconds, nanoseconds)
}
func (ck CursorKey) ID() uuid.UUID {
id, _ := uuid.FromBytes(ck[:])
return id
}
func (ck CursorKey) MarshalText() ([]byte, error) {
return []byte(ck.String()), nil
}
func (ck *CursorKey) UnmarshalText(data []byte) error {
ck2, err := ParseCursorKey(string(data))
if err != nil {
return err
}
*ck = ck2
return nil
}
func (ck CursorKey) MarshalBinary() ([]byte, error) {
return ck.Bytes(), nil
}
func (ck *CursorKey) UnmarshalBinary(b []byte) error {
ck2, err := CursorKeyFromBytes(b)
if err != nil {
return err
}
*ck = ck2
return nil
}

115
pkg/page/page.go Normal file
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@@ -0,0 +1,115 @@
// Copyright (c) 2025 Probo Inc <hello@getprobo.com>.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
package page
type (
Paginable interface {
CursorKey() CursorKey
}
PageInfo struct {
HasNext bool
HasPrev bool
}
Page[T Paginable] struct {
Info *PageInfo
Data []T
}
)
func (p *Page[T]) First() T {
if len(p.Data) == 0 {
var zero T
return zero
}
return p.Data[0]
}
func (p *Page[T]) Last() T {
if len(p.Data) == 0 {
var zero T
return zero
}
return p.Data[len(p.Data)-1]
}
func NewPage[T Paginable](data []T, c *Cursor) *Page[T] {
pi := &PageInfo{}
if len(data) == 0 {
return &Page[T]{
Info: pi,
Data: data,
}
}
edges := data
firstFromData := data[0]
switch c.Position {
case Head:
if c.Key != nil {
if len(edges) == c.Size+2 {
edges = edges[1 : len(edges)-1]
} else {
edges = edges[1:]
}
} else if c.Key == nil && len(edges) == c.Size+1 {
edges = edges[0 : len(edges)-1]
}
if c.Key != nil && *c.Key == firstFromData.CursorKey() {
pi.HasPrev = true
}
if c.Key != nil && c.Size+2 == len(data) {
pi.HasNext = true
} else if c.Key == nil && c.Size+1 == len(data) {
pi.HasNext = true
}
case Tail:
for i, j := 0, len(edges)-1; i < j; i, j = i+1, j-1 {
edges[i], edges[j] = edges[j], edges[i]
}
if c.Key != nil {
if len(edges) == c.Size+2 {
edges = edges[1 : len(edges)-1]
} else {
edges = edges[0 : len(edges)-1]
}
} else if c.Key == nil && len(edges) == c.Size+1 {
edges = edges[1:]
}
if c.Key != nil && *c.Key == firstFromData.CursorKey() {
pi.HasNext = true
}
if c.Key != nil && c.Size+2 == len(data) {
pi.HasPrev = true
} else if c.Key == nil && c.Size+1 == len(data) {
pi.HasPrev = true
}
}
return &Page[T]{
Info: pi,
Data: edges,
}
}