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.CreateOptions:
  30                 rOpts.Select = opts.Select
  31         case *arvados.UpdateOptions:
  32                 rOpts.Select = opts.Select
  33         case *arvados.GetOptions:
  34                 rOpts.Select = opts.Select
  35         case *arvados.ListOptions:
  36                 rOpts.Select = opts.Select
  37                 rOpts.Count = opts.Count
  38         case *arvados.GroupContentsOptions:
  39                 rOpts.Select = opts.Select
  40                 rOpts.Count = opts.Count
  41         }
  42         return rOpts, nil
  43 }
  44
  45 func applySelectParam(selectParam []string, orig map[string]interface{}) map[string]interface{} {
  46         if len(selectParam) == 0 {
  47                 return orig
  48         }
  49         selected := map[string]interface{}{}
  50         for _, attr := range selectParam {
  51                 if v, ok := orig[attr]; ok {
  52                         selected[attr] = v
  53                 }
  54         }
  55         // Some keys are always preserved, even if not requested
  56         for _, k := range []string{"etag", "kind", "writable_by"} {
  57                 if v, ok := orig[k]; ok {
  58                         selected[k] = v
  59                 }
  60         }
  61         return selected
  62 }
  63
  64 func (rtr *router) sendResponse(w http.ResponseWriter, req *http.Request, resp interface{}, opts responseOptions) {
  65         var tmp map[string]interface{}
  66
  67         if resp, ok := resp.(http.Handler); ok {
  68                 // resp knows how to write its own http response
  69                 // header and body.
  70                 resp.ServeHTTP(w, req)
  71                 return
  72         }
  73
  74         err := rtr.transcode(resp, &tmp)
  75         if err != nil {
  76                 rtr.sendError(w, err)
  77                 return
  78         }
  79
  80         respKind := kind(resp)
  81         if respKind != "" {
  82                 tmp["kind"] = respKind
  83         }
  84         if included, ok := tmp["included"]; ok && included == nil {
  85                 tmp["included"] = make([]interface{}, 0)
  86         }
  87         defaultItemKind := ""
  88         if strings.HasSuffix(respKind, "List") {
  89                 defaultItemKind = strings.TrimSuffix(respKind, "List")
  90         }
  91
  92         if _, isListResponse := tmp["items"].([]interface{}); isListResponse {
  93                 items, _ := tmp["items"].([]interface{})
  94                 included, _ := tmp["included"].([]interface{})
  95                 for _, slice := range [][]interface{}{items, included} {
  96                         for i, item := range slice {
  97                                 // Fill in "kind" by inspecting UUID/PDH if
  98                                 // possible; fall back on assuming each
  99                                 // Items[] entry in an "arvados#fooList"
 100                                 // response should have kind="arvados#foo".
 101                                 item, _ := item.(map[string]interface{})
 102                                 infix := ""
 103                                 if uuid, _ := item["uuid"].(string); len(uuid) == 27 {
 104                                         infix = uuid[6:11]
 105                                 }
 106                                 if k := kind(infixMap[infix]); k != "" {
 107                                         item["kind"] = k
 108                                 } else if pdh, _ := item["portable_data_hash"].(string); pdh != "" {
 109                                         item["kind"] = "arvados#collection"
 110                                 } else if defaultItemKind != "" {
 111                                         item["kind"] = defaultItemKind
 112                                 }
 113                                 item = applySelectParam(opts.Select, item)
 114                                 rtr.mungeItemFields(item)
 115                                 slice[i] = item
 116                         }
 117                 }
 118                 if opts.Count == "none" {
 119                         delete(tmp, "items_available")
 120                 }
 121         } else {
 122                 tmp = applySelectParam(opts.Select, tmp)
 123                 rtr.mungeItemFields(tmp)
 124         }
 125
 126         w.Header().Set("Content-Type", "application/json")
 127         enc := json.NewEncoder(w)
 128         enc.SetEscapeHTML(false)
 129         enc.Encode(tmp)
 130 }
 131
 132 func (rtr *router) sendError(w http.ResponseWriter, err error) {
 133         code := http.StatusInternalServerError
 134         if err, ok := err.(interface{ HTTPStatus() int }); ok {
 135                 code = err.HTTPStatus()
 136         }
 137         httpserver.Error(w, err.Error(), code)
 138 }
 139
 140 var infixMap = map[string]interface{}{
 141         "gj3su": arvados.APIClientAuthorization{},
 142         "4zz18": arvados.Collection{},
 143         "xvhdp": arvados.ContainerRequest{},
 144         "dz642": arvados.Container{},
 145         "j7d0g": arvados.Group{},
 146         "7fd4e": arvados.Workflow{},
 147 }
 148
 149 var specialKindTransforms = map[string]string{
 150         "arvados.APIClientAuthorization":     "arvados#apiClientAuthorization",
 151         "arvados.APIClientAuthorizationList": "arvados#apiClientAuthorizationList",
 152 }
 153
 154 var mungeKind = regexp.MustCompile(`\..`)
 155
 156 func kind(resp interface{}) string {
 157         t := fmt.Sprintf("%T", resp)
 158         if !strings.HasPrefix(t, "arvados.") {
 159                 return ""
 160         }
 161         if k, ok := specialKindTransforms[t]; ok {
 162                 return k
 163         }
 164         return mungeKind.ReplaceAllStringFunc(t, func(s string) string {
 165                 // "arvados.CollectionList" => "arvados#collectionList"
 166                 return "#" + strings.ToLower(s[1:])
 167         })
 168 }
 169
 170 func (rtr *router) mungeItemFields(tmp map[string]interface{}) {
 171         for k, v := range tmp {
 172                 if strings.HasSuffix(k, "_at") {
 173                         // Format non-nil timestamps as
 174                         // rfc3339NanoFixed (otherwise they would use
 175                         // the default time encoding, which omits
 176                         // trailing zeroes).
 177                         switch tv := v.(type) {
 178                         case *time.Time:
 179                                 if tv == nil || tv.IsZero() {
 180                                         tmp[k] = nil
 181                                 } else {
 182                                         tmp[k] = tv.Format(rfc3339NanoFixed)
 183                                 }
 184                         case time.Time:
 185                                 if tv.IsZero() {
 186                                         tmp[k] = nil
 187                                 } else {
 188                                         tmp[k] = tv.Format(rfc3339NanoFixed)
 189                                 }
 190                         case string:
 191                                 if tv == "" {
 192                                         tmp[k] = nil
 193                                 } else if t, err := time.Parse(time.RFC3339Nano, tv); err != nil {
 194                                         // pass through an invalid time value (?)
 195                                 } else if t.IsZero() {
 196                                         tmp[k] = nil
 197                                 } else {
 198                                         tmp[k] = t.Format(rfc3339NanoFixed)
 199                                 }
 200                         }
 201                 }
 202                 // Arvados API spec says when these fields are empty
 203                 // they appear in responses as null, rather than a
 204                 // zero value.
 205                 switch k {
 206                 case "output_uuid", "output_name", "log_uuid", "description", "requesting_container_uuid", "container_uuid", "modified_by_client_uuid", "frozen_by_uuid":
 207                         if v == "" {
 208                                 tmp[k] = nil
 209                         }
 210                 case "container_count_max":
 211                         if v == float64(0) {
 212                                 tmp[k] = nil
 213                         }
 214                 }
 215         }
 216 }