82 lines
1.4 KiB
Go
82 lines
1.4 KiB
Go
package domain
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import (
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"bytes"
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"encoding/base64"
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"net/url"
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"strings"
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)
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func parseURL(rawURL string) (*url.URL, error) {
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u, err := url.ParseRequestURI(rawURL)
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if err != nil {
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return nil, InvalidURLError{
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URL: rawURL,
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}
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}
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return u, nil
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}
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const (
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cursorSeparator = ","
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cursorKeyValueSeparator = "="
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)
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func encodeCursor(s [][2]string) string {
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if len(s) == 0 {
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return ""
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}
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n := len(cursorSeparator) * (len(s) - 1)
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for _, el := range s {
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n += len(el[0]) + len(el[1]) + len(cursorKeyValueSeparator)
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}
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var b bytes.Buffer
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b.Grow(n)
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for _, el := range s {
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if b.Len() > 0 {
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_, _ = b.WriteString(cursorSeparator)
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}
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_, _ = b.WriteString(el[0])
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_, _ = b.WriteString(cursorKeyValueSeparator)
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_, _ = b.WriteString(el[1])
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}
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return base64.StdEncoding.EncodeToString(b.Bytes())
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}
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const (
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encodedCursorMinLength = 1
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encodedCursorMaxLength = 1000
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)
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func decodeCursor(s string) (map[string]string, error) {
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if err := validateStringLen(s, encodedCursorMinLength, encodedCursorMaxLength); err != nil {
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return nil, err
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}
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decodedBytes, err := base64.StdEncoding.DecodeString(s)
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if err != nil {
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return nil, ErrInvalidCursor
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}
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decoded := string(decodedBytes)
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kvs := strings.Split(decoded, cursorSeparator)
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m := make(map[string]string, len(kvs))
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for _, kv := range kvs {
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k, v, found := strings.Cut(kv, cursorKeyValueSeparator)
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if !found {
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return nil, ErrInvalidCursor
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}
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m[k] = v
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}
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return m, nil
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}
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