podman

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// Copyright 2015 go-swagger maintainers
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//    http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package runtime
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import (
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	"bytes"
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	"encoding"
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	"errors"
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	"fmt"
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	"io"
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	"reflect"
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	"github.com/go-openapi/swag"
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)
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func defaultCloser() error { return nil }
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type byteStreamOpt func(opts *byteStreamOpts)
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// ClosesStream when the bytestream consumer or producer is finished
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func ClosesStream(opts *byteStreamOpts) {
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	opts.Close = true
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}
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type byteStreamOpts struct {
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	Close bool
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}
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// ByteStreamConsumer creates a consumer for byte streams,
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// takes a Writer/BinaryUnmarshaler interface or binary slice by reference,
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// and reads from the provided reader
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func ByteStreamConsumer(opts ...byteStreamOpt) Consumer {
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	var vals byteStreamOpts
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	for _, opt := range opts {
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		opt(&vals)
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	}
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	return ConsumerFunc(func(reader io.Reader, data interface{}) error {
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		if reader == nil {
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			return errors.New("ByteStreamConsumer requires a reader") // early exit
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		}
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		close := defaultCloser
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		if vals.Close {
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			if cl, ok := reader.(io.Closer); ok {
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				close = cl.Close
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			}
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		}
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		//nolint:errcheck // closing a reader wouldn't fail.
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		defer close()
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		if wrtr, ok := data.(io.Writer); ok {
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			_, err := io.Copy(wrtr, reader)
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			return err
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		}
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		buf := new(bytes.Buffer)
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		_, err := buf.ReadFrom(reader)
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		if err != nil {
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			return err
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		}
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		b := buf.Bytes()
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		if bu, ok := data.(encoding.BinaryUnmarshaler); ok {
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			return bu.UnmarshalBinary(b)
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		}
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		if data != nil {
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			if str, ok := data.(*string); ok {
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				*str = string(b)
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				return nil
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			}
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		}
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		if t := reflect.TypeOf(data); data != nil && t.Kind() == reflect.Ptr {
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			v := reflect.Indirect(reflect.ValueOf(data))
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			if t = v.Type(); t.Kind() == reflect.Slice && t.Elem().Kind() == reflect.Uint8 {
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				v.SetBytes(b)
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				return nil
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			}
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		}
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		return fmt.Errorf("%v (%T) is not supported by the ByteStreamConsumer, %s",
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			data, data, "can be resolved by supporting Writer/BinaryUnmarshaler interface")
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	})
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}
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// ByteStreamProducer creates a producer for byte streams,
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// takes a Reader/BinaryMarshaler interface or binary slice,
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// and writes to a writer (essentially a pipe)
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func ByteStreamProducer(opts ...byteStreamOpt) Producer {
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	var vals byteStreamOpts
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	for _, opt := range opts {
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		opt(&vals)
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	}
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	return ProducerFunc(func(writer io.Writer, data interface{}) error {
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		if writer == nil {
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			return errors.New("ByteStreamProducer requires a writer") // early exit
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		}
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		close := defaultCloser
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		if vals.Close {
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			if cl, ok := writer.(io.Closer); ok {
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				close = cl.Close
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			}
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		}
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		//nolint:errcheck // TODO: closing a writer would fail.
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		defer close()
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		if rc, ok := data.(io.ReadCloser); ok {
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			defer rc.Close()
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		}
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		if rdr, ok := data.(io.Reader); ok {
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			_, err := io.Copy(writer, rdr)
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			return err
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		}
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		if bm, ok := data.(encoding.BinaryMarshaler); ok {
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			bytes, err := bm.MarshalBinary()
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			if err != nil {
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				return err
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			}
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			_, err = writer.Write(bytes)
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			return err
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		}
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		if data != nil {
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			if str, ok := data.(string); ok {
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				_, err := writer.Write([]byte(str))
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				return err
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			}
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			if e, ok := data.(error); ok {
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				_, err := writer.Write([]byte(e.Error()))
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				return err
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			}
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			v := reflect.Indirect(reflect.ValueOf(data))
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			if t := v.Type(); t.Kind() == reflect.Slice && t.Elem().Kind() == reflect.Uint8 {
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				_, err := writer.Write(v.Bytes())
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				return err
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			}
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			if t := v.Type(); t.Kind() == reflect.Struct || t.Kind() == reflect.Slice {
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				b, err := swag.WriteJSON(data)
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				if err != nil {
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					return err
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				}
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				_, err = writer.Write(b)
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				return err
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			}
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		}
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		return fmt.Errorf("%v (%T) is not supported by the ByteStreamProducer, %s",
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			data, data, "can be resolved by supporting Reader/BinaryMarshaler interface")
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	})
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}
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