github.com/uber/kraken@v0.1.4/lib/backend/testfs/server.go (about)

     1  // Copyright (c) 2016-2019 Uber Technologies, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  package testfs
    15  
    16  import (
    17  	"encoding/json"
    18  	"fmt"
    19  	"io"
    20  	"io/ioutil"
    21  	"net/http"
    22  	"os"
    23  	"path/filepath"
    24  	"strconv"
    25  	"strings"
    26  	"sync"
    27  
    28  	"github.com/uber/kraken/utils/handler"
    29  
    30  	"github.com/pressly/chi"
    31  )
    32  
    33  // Server provides HTTP endpoints for operating on files on disk.
    34  type Server struct {
    35  	sync.RWMutex
    36  	dir string
    37  }
    38  
    39  // NewServer creates a new Server.
    40  func NewServer() *Server {
    41  	dir, err := ioutil.TempDir("/tmp", "kraken-testfs")
    42  	if err != nil {
    43  		panic(err)
    44  	}
    45  	return &Server{dir: dir}
    46  }
    47  
    48  // Handler returns an HTTP handler for s.
    49  func (s *Server) Handler() http.Handler {
    50  	r := chi.NewRouter()
    51  	r.Get("/health", s.healthHandler)
    52  	r.Head("/files/*", handler.Wrap(s.statHandler))
    53  	r.Get("/files/*", handler.Wrap(s.downloadHandler))
    54  	r.Post("/files/*", handler.Wrap(s.uploadHandler))
    55  	r.Get("/list/*", handler.Wrap(s.listHandler))
    56  	return r
    57  }
    58  
    59  // Cleanup cleans up the underlying directory of s.
    60  func (s *Server) Cleanup() {
    61  	os.RemoveAll(s.dir)
    62  }
    63  
    64  func (s *Server) healthHandler(w http.ResponseWriter, r *http.Request) {
    65  	w.Write([]byte("OK"))
    66  }
    67  
    68  func (s *Server) statHandler(w http.ResponseWriter, r *http.Request) error {
    69  	s.RLock()
    70  	defer s.RUnlock()
    71  
    72  	name := r.URL.Path[len("/files/"):]
    73  
    74  	info, err := os.Stat(s.path(name))
    75  	if err != nil {
    76  		if os.IsNotExist(err) {
    77  			return handler.ErrorStatus(http.StatusNotFound)
    78  		}
    79  		return handler.Errorf("file store: %s", err)
    80  	}
    81  	w.Header().Add("Size", strconv.FormatInt(info.Size(), 10))
    82  	w.WriteHeader(http.StatusOK)
    83  	return nil
    84  }
    85  
    86  func (s *Server) downloadHandler(w http.ResponseWriter, r *http.Request) error {
    87  	s.RLock()
    88  	defer s.RUnlock()
    89  
    90  	name := r.URL.Path[len("/files/"):]
    91  
    92  	f, err := os.Open(s.path(name))
    93  	if err != nil {
    94  		if os.IsNotExist(err) {
    95  			return handler.ErrorStatus(http.StatusNotFound)
    96  		}
    97  		return handler.Errorf("open: %s", err)
    98  	}
    99  	if _, err := io.Copy(w, f); err != nil {
   100  		return handler.Errorf("copy: %s", err)
   101  	}
   102  	return nil
   103  }
   104  
   105  func (s *Server) uploadHandler(w http.ResponseWriter, r *http.Request) error {
   106  	s.Lock()
   107  	defer s.Unlock()
   108  
   109  	name := r.URL.Path[len("/files/"):]
   110  
   111  	p := s.path(name)
   112  	if err := os.MkdirAll(filepath.Dir(p), 0775); err != nil {
   113  		return handler.Errorf("mkdir: %s", err)
   114  	}
   115  	f, err := os.Create(p)
   116  	if err != nil {
   117  		return handler.Errorf("create: %s", err)
   118  	}
   119  	defer f.Close()
   120  	if _, err := io.Copy(f, r.Body); err != nil {
   121  		return handler.Errorf("copy: %s", err)
   122  	}
   123  	return nil
   124  }
   125  
   126  func (s *Server) listHandler(w http.ResponseWriter, r *http.Request) error {
   127  	s.RLock()
   128  	defer s.RUnlock()
   129  
   130  	prefix := s.path(r.URL.Path[len("/list/"):])
   131  
   132  	var paths []string
   133  	err := filepath.Walk(prefix, func(path string, info os.FileInfo, err error) error {
   134  		if err != nil {
   135  			return err
   136  		}
   137  		if info.IsDir() {
   138  			return nil
   139  		}
   140  		if path == prefix {
   141  			// Handle case where prefix is a file.
   142  			return nil
   143  		}
   144  		path, err = filepath.Rel(s.dir, path)
   145  		if err != nil {
   146  			return err
   147  		}
   148  		paths = append(paths, path)
   149  		return nil
   150  	})
   151  	if err != nil {
   152  		return fmt.Errorf("walk: %s", err)
   153  	}
   154  	if err := json.NewEncoder(w).Encode(&paths); err != nil {
   155  		return handler.Errorf("json encode: %s", err)
   156  	}
   157  	return nil
   158  }
   159  
   160  // path normalizes some file or directory entry into a path.
   161  func (s *Server) path(entry string) string {
   162  	// Allows listing tags by repo.
   163  	entry = strings.Replace(entry, ":", "/", -1)
   164  	return filepath.Join(s.dir, entry)
   165  }