lib/controller/router/response.go

   1 // Copyright (C) The Arvados Authors. All rights reserved.
   2 //
   3 // SPDX-License-Identifier: AGPL-3.0
   4
   5 package router
   6
   7 import (
   8         "encoding/json"
   9         "fmt"
  10         "net/http"
  11         "regexp"
  12         "strings"
  13         "time"
  14
  15         "git.arvados.org/arvados.git/sdk/go/arvados"
  16         "git.arvados.org/arvados.git/sdk/go/httpserver"
  17 )
  18
  19 const rfc3339NanoFixed = "2006-01-02T15:04:05.000000000Z07:00"
  20
  21 type responseOptions struct {
  22         Select []string
  23         Count  string
  24 }
  25
  26 func (rtr *router) responseOptions(opts interface{}) (responseOptions, error) {
  27         var rOpts responseOptions
  28         switch opts := opts.(type) {
  29         case *arvados.GetOptions:
  30                 rOpts.Select = opts.Select
  31         case *arvados.ListOptions:
  32                 rOpts.Select = opts.Select
  33                 rOpts.Count = opts.Count
  34         }
  35         return rOpts, nil
  36 }
  37
  38 func applySelectParam(selectParam []string, orig map[string]interface{}) map[string]interface{} {
  39         if len(selectParam) == 0 {
  40                 return orig
  41         }
  42         selected := map[string]interface{}{}
  43         for _, attr := range selectParam {
  44                 if v, ok := orig[attr]; ok {
  45                         selected[attr] = v
  46                 }
  47         }
  48         // Some keys are always preserved, even if not requested
  49         for _, k := range []string{"etag", "kind", "writable_by"} {
  50                 if v, ok := orig[k]; ok {
  51                         selected[k] = v
  52                 }
  53         }
  54         return selected
  55 }
  56
  57 func (rtr *router) sendResponse(w http.ResponseWriter, req *http.Request, resp interface{}, opts responseOptions) {
  58         var tmp map[string]interface{}
  59
  60         if resp, ok := resp.(http.Handler); ok {
  61                 // resp knows how to write its own http response
  62                 // header and body.
  63                 resp.ServeHTTP(w, req)
  64                 return
  65         }
  66
  67         err := rtr.transcode(resp, &tmp)
  68         if err != nil {
  69                 rtr.sendError(w, err)
  70                 return
  71         }
  72
  73         respKind := kind(resp)
  74         if respKind != "" {
  75                 tmp["kind"] = respKind
  76         }
  77         if included, ok := tmp["included"]; ok && included == nil {
  78                 tmp["included"] = make([]interface{}, 0)
  79         }
  80         defaultItemKind := ""
  81         if strings.HasSuffix(respKind, "List") {
  82                 defaultItemKind = strings.TrimSuffix(respKind, "List")
  83         }
  84
  85         if _, isListResponse := tmp["items"].([]interface{}); isListResponse {
  86                 items, _ := tmp["items"].([]interface{})
  87                 included, _ := tmp["included"].([]interface{})
  88                 for _, slice := range [][]interface{}{items, included} {
  89                         for i, item := range slice {
  90                                 // Fill in "kind" by inspecting UUID/PDH if
  91                                 // possible; fall back on assuming each
  92                                 // Items[] entry in an "arvados#fooList"
  93                                 // response should have kind="arvados#foo".
  94                                 item, _ := item.(map[string]interface{})
  95                                 infix := ""
  96                                 if uuid, _ := item["uuid"].(string); len(uuid) == 27 {
  97                                         infix = uuid[6:11]
  98                                 }
  99                                 if k := kind(infixMap[infix]); k != "" {
 100                                         item["kind"] = k
 101                                 } else if pdh, _ := item["portable_data_hash"].(string); pdh != "" {
 102                                         item["kind"] = "arvados#collection"
 103                                 } else if defaultItemKind != "" {
 104                                         item["kind"] = defaultItemKind
 105                                 }
 106                                 item = applySelectParam(opts.Select, item)
 107                                 rtr.mungeItemFields(item)
 108                                 slice[i] = item
 109                         }
 110                 }
 111                 if opts.Count == "none" {
 112                         delete(tmp, "items_available")
 113                 }
 114         } else {
 115                 tmp = applySelectParam(opts.Select, tmp)
 116                 rtr.mungeItemFields(tmp)
 117         }
 118
 119         w.Header().Set("Content-Type", "application/json")
 120         enc := json.NewEncoder(w)
 121         enc.SetEscapeHTML(false)
 122         enc.Encode(tmp)
 123 }
 124
 125 func (rtr *router) sendError(w http.ResponseWriter, err error) {
 126         code := http.StatusInternalServerError
 127         if err, ok := err.(interface{ HTTPStatus() int }); ok {
 128                 code = err.HTTPStatus()
 129         }
 130         httpserver.Error(w, err.Error(), code)
 131 }
 132
 133 var infixMap = map[string]interface{}{
 134         "4zz18": arvados.Collection{},
 135         "xvhdp": arvados.ContainerRequest{},
 136         "dz642": arvados.Container{},
 137         "j7d0g": arvados.Group{},
 138         "8i9sb": arvados.Job{},
 139         "d1hrv": arvados.PipelineInstance{},
 140         "p5p6p": arvados.PipelineTemplate{},
 141         "j58dm": arvados.Specimen{},
 142         "q1cn2": arvados.Trait{},
 143         "7fd4e": arvados.Workflow{},
 144 }
 145
 146 var mungeKind = regexp.MustCompile(`\..`)
 147
 148 func kind(resp interface{}) string {
 149         t := fmt.Sprintf("%T", resp)
 150         if !strings.HasPrefix(t, "arvados.") {
 151                 return ""
 152         }
 153         return mungeKind.ReplaceAllStringFunc(t, func(s string) string {
 154                 // "arvados.CollectionList" => "arvados#collectionList"
 155                 return "#" + strings.ToLower(s[1:])
 156         })
 157 }
 158
 159 func (rtr *router) mungeItemFields(tmp map[string]interface{}) {
 160         for k, v := range tmp {
 161                 if strings.HasSuffix(k, "_at") {
 162                         // Format non-nil timestamps as
 163                         // rfc3339NanoFixed (otherwise they would use
 164                         // the default time encoding, which omits
 165                         // trailing zeroes).
 166                         switch tv := v.(type) {
 167                         case *time.Time:
 168                                 if tv == nil || tv.IsZero() {
 169                                         tmp[k] = nil
 170                                 } else {
 171                                         tmp[k] = tv.Format(rfc3339NanoFixed)
 172                                 }
 173                         case time.Time:
 174                                 if tv.IsZero() {
 175                                         tmp[k] = nil
 176                                 } else {
 177                                         tmp[k] = tv.Format(rfc3339NanoFixed)
 178                                 }
 179                         case string:
 180                                 if tv == "" {
 181                                         tmp[k] = nil
 182                                 } else if t, err := time.Parse(time.RFC3339Nano, tv); err != nil {
 183                                         // pass through an invalid time value (?)
 184                                 } else if t.IsZero() {
 185                                         tmp[k] = nil
 186                                 } else {
 187                                         tmp[k] = t.Format(rfc3339NanoFixed)
 188                                 }
 189                         }
 190                 }
 191                 // Arvados API spec says when these fields are empty
 192                 // they appear in responses as null, rather than a
 193                 // zero value.
 194                 switch k {
 195                 case "output_uuid", "output_name", "log_uuid", "description", "requesting_container_uuid", "container_uuid":
 196                         if v == "" {
 197                                 tmp[k] = nil
 198                         }
 199                 case "container_count_max":
 200                         if v == float64(0) {
 201                                 tmp[k] = nil
 202                         }
 203                 }
 204         }
 205 }