func generatePagingLinks(r *http.Request, query search.Query, total uint32) []models.BundleLinkComponent {
links := make([]models.BundleLinkComponent, 0, 5)
values := query.NormalizedQueryValues(false)
options := query.Options()
count := uint32(options.Count)
offset := uint32(options.Offset)
// First create the base URL for paging
baseURL := responseURL(r, query.Resource)
// Self link
links = append(links, newLink("self", baseURL, values, count, offset))
// First link
links = append(links, newLink("first", baseURL, values, count, uint32(0)))
// Previous link
if offset > uint32(0) {
newOffset := offset - count
// Handle case where paging is uneven (e.g., count=10&offset=5)
if count > offset {
newOffset = uint32(0)
}
links = append(links, newLink("previous", baseURL, values, offset-newOffset, newOffset))
}
// Next Link
if total > (offset + count) {
links = append(links, newLink("next", baseURL, values, count, offset+count))
}
// Last Link
remainder := (total - offset) % count
if total < offset {
remainder = uint32(0)
}
newOffset := total - remainder
if remainder == uint32(0) && total > count {
newOffset = total - count
}
links = append(links, newLink("last", baseURL, values, count, newOffset))
return links
}
func (dal *mongoDataAccessLayer) Search(baseURL url.URL, searchQuery search.Query) (*models.Bundle, error) {
searcher := search.NewMongoSearcher(dal.Database)
var result interface{}
var err error
usesIncludes := len(searchQuery.Options().Include) > 0
usesRevIncludes := len(searchQuery.Options().RevInclude) > 0
// Only use (slower) pipeline if it is needed
if usesIncludes || usesRevIncludes {
result = models.NewSlicePlusForResourceName(searchQuery.Resource, 0, 0)
err = searcher.CreatePipeline(searchQuery).All(result)
} else {
result = models.NewSliceForResourceName(searchQuery.Resource, 0, 0)
err = searcher.CreateQuery(searchQuery).All(result)
}
if err != nil {
return nil, convertMongoErr(err)
}
includesMap := make(map[string]interface{})
var entryList []models.BundleEntryComponent
resultVal := reflect.ValueOf(result).Elem()
for i := 0; i < resultVal.Len(); i++ {
var entry models.BundleEntryComponent
entry.Resource = resultVal.Index(i).Addr().Interface()
entry.Search = &models.BundleEntrySearchComponent{Mode: "match"}
entryList = append(entryList, entry)
if usesIncludes || usesRevIncludes {
rpi, ok := entry.Resource.(ResourcePlusRelatedResources)
if ok {
for k, v := range rpi.GetIncludedAndRevIncludedResources() {
includesMap[k] = v
}
}
}
}
for _, v := range includesMap {
var entry models.BundleEntryComponent
entry.Resource = v
entry.Search = &models.BundleEntrySearchComponent{Mode: "include"}
entryList = append(entryList, entry)
}
var bundle models.Bundle
bundle.Id = bson.NewObjectId().Hex()
bundle.Type = "searchset"
bundle.Entry = entryList
options := searchQuery.Options()
// Need to get the true total (not just how many were returned in this response)
var total uint32
if resultVal.Len() == options.Count || resultVal.Len() == 0 {
// Need to get total count from the server, since there may be more or the offset was too high
intTotal, err := searcher.CreateQueryWithoutOptions(searchQuery).Count()
if err != nil {
return nil, convertMongoErr(err)
}
total = uint32(intTotal)
} else {
// We can figure out the total by adding the offset and # results returned
total = uint32(options.Offset + resultVal.Len())
}
bundle.Total = &total
// Add links for paging
bundle.Link = generatePagingLinks(baseURL, searchQuery, total)
return &bundle, nil
}
func (rc *ResourceController) IndexHandler(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
defer func() {
if r := recover(); r != nil {
rw.Header().Set("Content-Type", "application/json; charset=utf-8")
switch x := r.(type) {
case search.Error:
rw.WriteHeader(x.HTTPStatus)
json.NewEncoder(rw).Encode(x.OperationOutcome)
return
default:
outcome := &models.OperationOutcome{
Issue: []models.OperationOutcomeIssueComponent{
models.OperationOutcomeIssueComponent{
Severity: "fatal",
Code: "exception",
},
},
}
rw.WriteHeader(http.StatusInternalServerError)
json.NewEncoder(rw).Encode(outcome)
}
}
}()
result := models.NewSliceForResourceName(rc.Name, 0, 0)
// Create and execute the Mongo query based on the http query params
searcher := search.NewMongoSearcher(Database)
searchQuery := search.Query{Resource: rc.Name, Query: r.URL.RawQuery}
mgoQuery := searcher.CreateQuery(searchQuery)
// Horrible, horrible hack (for now) to ensure patients are sorted by name. This is needed by
// the frontend, else paging won't work correctly. This should be removed when the general
// sorting feature is implemented.
if rc.Name == "Patient" {
// To add insult to injury, mongo will not let us sort by family *and* given name:
// Executor error: BadValue cannot sort with keys that are parallel arrays
mgoQuery = mgoQuery.Sort("name.0.family.0" /*", name.0.given.0"*/, "_id")
}
err := mgoQuery.All(result)
if err != nil {
http.Error(rw, err.Error(), http.StatusInternalServerError)
}
var entryList []models.BundleEntryComponent
resultVal := reflect.ValueOf(result).Elem()
for i := 0; i < resultVal.Len(); i++ {
var entry models.BundleEntryComponent
entry.Resource = resultVal.Index(i).Addr().Interface()
entryList = append(entryList, entry)
}
var bundle models.Bundle
bundle.Id = bson.NewObjectId().Hex()
bundle.Type = "searchset"
bundle.Entry = entryList
options := searchQuery.Options()
// Need to get the true total (not just how many were returned in this response)
var total uint32
if resultVal.Len() == options.Count || resultVal.Len() == 0 {
// Need to get total count from the server, since there may be more or the offset was too high
intTotal, err := searcher.CreateQueryWithoutOptions(searchQuery).Count()
if err != nil {
http.Error(rw, err.Error(), http.StatusInternalServerError)
}
total = uint32(intTotal)
} else {
// We can figure out the total by adding the offset and # results returned
total = uint32(options.Offset + resultVal.Len())
}
bundle.Total = &total
// Add links for paging
bundle.Link = generatePagingLinks(r, searchQuery, total)
context.Set(r, rc.Name, reflect.ValueOf(result).Elem().Interface())
context.Set(r, "Resource", rc.Name)
context.Set(r, "Action", "search")
rw.Header().Set("Content-Type", "application/json; charset=utf-8")
rw.Header().Set("Access-Control-Allow-Origin", "*")
json.NewEncoder(rw).Encode(&bundle)
}