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
  81         defaultItemKind := ""
  82         if strings.HasSuffix(respKind, "List") {
  83                 defaultItemKind = strings.TrimSuffix(respKind, "List")
  84         }
  85
  86         if items, ok := tmp["items"].([]interface{}); ok {
  87                 for i, item := range items {
  88                         // Fill in "kind" by inspecting UUID/PDH if
  89                         // possible; fall back on assuming each
  90                         // Items[] entry in an "arvados#fooList"
  91                         // response should have kind="arvados#foo".
  92                         item, _ := item.(map[string]interface{})
  93                         infix := ""
  94                         if uuid, _ := item["uuid"].(string); len(uuid) == 27 {
  95                                 infix = uuid[6:11]
  96                         }
  97                         if k := kind(infixMap[infix]); k != "" {
  98                                 item["kind"] = k
  99                         } else if pdh, _ := item["portable_data_hash"].(string); pdh != "" {
 100                                 item["kind"] = "arvados#collection"
 101                         } else if defaultItemKind != "" {
 102                                 item["kind"] = defaultItemKind
 103                         }
 104                         item = applySelectParam(opts.Select, item)
 105                         rtr.mungeItemFields(item)
 106                         items[i] = item
 107                 }
 108                 if opts.Count == "none" {
 109                         delete(tmp, "items_available")
 110                 }
 111         } else {
 112                 tmp = applySelectParam(opts.Select, tmp)
 113                 rtr.mungeItemFields(tmp)
 114         }
 115
 116         w.Header().Set("Content-Type", "application/json")
 117         enc := json.NewEncoder(w)
 118         enc.SetEscapeHTML(false)
 119         enc.Encode(tmp)
 120 }
 121
 122 func (rtr *router) sendError(w http.ResponseWriter, err error) {
 123         code := http.StatusInternalServerError
 124         if err, ok := err.(interface{ HTTPStatus() int }); ok {
 125                 code = err.HTTPStatus()
 126         }
 127         httpserver.Error(w, err.Error(), code)
 128 }
 129
 130 var infixMap = map[string]interface{}{
 131         "4zz18": arvados.Collection{},
 132         "xvhdp": arvados.ContainerRequest{},
 133         "dz642": arvados.Container{},
 134         "j7d0g": arvados.Group{},
 135         "8i9sb": arvados.Job{},
 136         "d1hrv": arvados.PipelineInstance{},
 137         "p5p6p": arvados.PipelineTemplate{},
 138         "j58dm": arvados.Specimen{},
 139         "q1cn2": arvados.Trait{},
 140         "7fd4e": arvados.Workflow{},
 141 }
 142
 143 var mungeKind = regexp.MustCompile(`\..`)
 144
 145 func kind(resp interface{}) string {
 146         t := fmt.Sprintf("%T", resp)
 147         if !strings.HasPrefix(t, "arvados.") {
 148                 return ""
 149         }
 150         return mungeKind.ReplaceAllStringFunc(t, func(s string) string {
 151                 // "arvados.CollectionList" => "arvados#collectionList"
 152                 return "#" + strings.ToLower(s[1:])
 153         })
 154 }
 155
 156 func (rtr *router) mungeItemFields(tmp map[string]interface{}) {
 157         for k, v := range tmp {
 158                 if strings.HasSuffix(k, "_at") {
 159                         // Format non-nil timestamps as
 160                         // rfc3339NanoFixed (otherwise they would use
 161                         // the default time encoding, which omits
 162                         // trailing zeroes).
 163                         switch tv := v.(type) {
 164                         case *time.Time:
 165                                 if tv == nil || tv.IsZero() {
 166                                         tmp[k] = nil
 167                                 } else {
 168                                         tmp[k] = tv.Format(rfc3339NanoFixed)
 169                                 }
 170                         case time.Time:
 171                                 if tv.IsZero() {
 172                                         tmp[k] = nil
 173                                 } else {
 174                                         tmp[k] = tv.Format(rfc3339NanoFixed)
 175                                 }
 176                         case string:
 177                                 if tv == "" {
 178                                         tmp[k] = nil
 179                                 } else if t, err := time.Parse(time.RFC3339Nano, tv); err != nil {
 180                                         // pass through an invalid time value (?)
 181                                 } else if t.IsZero() {
 182                                         tmp[k] = nil
 183                                 } else {
 184                                         tmp[k] = t.Format(rfc3339NanoFixed)
 185                                 }
 186                         }
 187                 }
 188                 // Arvados API spec says when these fields are empty
 189                 // they appear in responses as null, rather than a
 190                 // zero value.
 191                 switch k {
 192                 case "output_uuid", "output_name", "log_uuid", "description", "requesting_container_uuid", "container_uuid":
 193                         if v == "" {
 194                                 tmp[k] = nil
 195                         }
 196                 case "container_count_max":
 197                         if v == float64(0) {
 198                                 tmp[k] = nil
 199                         }
 200                 }
 201         }
 202 }