Merge branch 'master' into 15572-new-install-docs

[arvados.git] / lib / controller / federation / list.go

diff --git a/lib/controller/federation/list.go b/lib/controller/federation/list.go
index 6ba184c471a1f4df37493520d7df9c46c7fcfaf7..97c201e742c9ee65eeae759c4e8d9bb63304c154 100644 (file)
--- a/lib/controller/federation/list.go
+++ b/lib/controller/federation/list.go
@@ -10,9 +10,10 @@ import (
        "net/http"
        "sort"
        "sync"
+       "sync/atomic"
 
-       "git.curoverse.com/arvados.git/sdk/go/arvados"
-       "git.curoverse.com/arvados.git/sdk/go/httpserver"
+       "git.arvados.org/arvados.git/sdk/go/arvados"
+       "git.arvados.org/arvados.git/sdk/go/httpserver"
 )
 
 //go:generate go run generate.go
@@ -20,9 +21,11 @@ import (
 // CollectionList is used as a template to auto-generate List()
 // methods for other types; see generate.go.
 
-func (conn *Conn) CollectionList(ctx context.Context, options arvados.ListOptions) (arvados.CollectionList, error) {
+func (conn *Conn) generated_CollectionList(ctx context.Context, options arvados.ListOptions) (arvados.CollectionList, error) {
        var mtx sync.Mutex
        var merged arvados.CollectionList
+       var needSort atomic.Value
+       needSort.Store(false)
        err := conn.splitListRequest(ctx, options, func(ctx context.Context, _ string, backend arvados.API, options arvados.ListOptions) ([]string, error) {
                cl, err := backend.CollectionList(ctx, options)
                if err != nil {
@@ -32,8 +35,9 @@ func (conn *Conn) CollectionList(ctx context.Context, options arvados.ListOption
                defer mtx.Unlock()
                if len(merged.Items) == 0 {
                        merged = cl
-               } else {
+               } else if len(cl.Items) > 0 {
                        merged.Items = append(merged.Items, cl.Items...)
+                       needSort.Store(true)
                }
                uuids := make([]string, 0, len(cl.Items))
                for _, item := range cl.Items {
@@ -41,7 +45,19 @@ func (conn *Conn) CollectionList(ctx context.Context, options arvados.ListOption
                }
                return uuids, nil
        })
-       sort.Slice(merged.Items, func(i, j int) bool { return merged.Items[i].UUID < merged.Items[j].UUID })
+       if needSort.Load().(bool) {
+               // Apply the default/implied order, "modified_at desc"
+               sort.Slice(merged.Items, func(i, j int) bool {
+                       mi, mj := merged.Items[i].ModifiedAt, merged.Items[j].ModifiedAt
+                       return mj.Before(mi)
+               })
+       }
+       if merged.Items == nil {
+               // Return empty results as [], not null
+               // (https://github.com/golang/go/issues/27589 might be
+               // a better solution in the future)
+               merged.Items = []arvados.Collection{}
+       }
        return merged, err
 }
 
@@ -221,7 +237,7 @@ func (conn *Conn) splitListRequest(ctx context.Context, opts arvados.ListOptions
 
                                done, err := fn(ctx, clusterID, backend, remoteOpts)
                                if err != nil {
-                                       errs <- err
+                                       errs <- httpErrorf(http.StatusBadGateway, err.Error())
                                        return
                                }
                                progress := false
@@ -231,8 +247,13 @@ func (conn *Conn) splitListRequest(ctx context.Context, opts arvados.ListOptions
                                                delete(todo, uuid)
                                        }
                                }
-                               if !progress {
-                                       errs <- httpErrorf(http.StatusBadGateway, "cannot make progress in federated list query: cluster %q returned none of the requested UUIDs", clusterID)
+                               if len(done) == 0 {
+                                       // Zero items == no more
+                                       // results exist, no need to
+                                       // get another page.
+                                       break
+                               } else if !progress {
+                                       errs <- httpErrorf(http.StatusBadGateway, "cannot make progress in federated list query: cluster %q returned %d items but none had the requested UUIDs", clusterID, len(done))
                                        return
                                }
                        }