1 // Copyright (C) The Arvados Authors. All rights reserved.
3 // SPDX-License-Identifier: AGPL-3.0
15 "git.curoverse.com/arvados.git/sdk/go/arvados"
16 "git.curoverse.com/arvados.git/sdk/go/httpserver"
19 //go:generate go run generate.go
21 // CollectionList is used as a template to auto-generate List()
22 // methods for other types; see generate.go.
24 func (conn *Conn) CollectionList(ctx context.Context, options arvados.ListOptions) (arvados.CollectionList, error) {
26 var merged arvados.CollectionList
27 var needSort atomic.Value
29 err := conn.splitListRequest(ctx, options, func(ctx context.Context, _ string, backend arvados.API, options arvados.ListOptions) ([]string, error) {
30 cl, err := backend.CollectionList(ctx, options)
36 if len(merged.Items) == 0 {
38 } else if len(cl.Items) > 0 {
39 merged.Items = append(merged.Items, cl.Items...)
42 uuids := make([]string, 0, len(cl.Items))
43 for _, item := range cl.Items {
44 uuids = append(uuids, item.UUID)
48 if needSort.Load().(bool) {
49 // Apply the default/implied order, "modified_at desc"
50 sort.Slice(merged.Items, func(i, j int) bool {
51 mi, mj := merged.Items[i].ModifiedAt, merged.Items[j].ModifiedAt
58 // Call fn on one or more local/remote backends if opts indicates a
59 // federation-wide list query, i.e.:
61 // * There is at least one filter of the form
62 // ["uuid","in",[a,b,c,...]] or ["uuid","=",a]
64 // * One or more of the supplied UUIDs (a,b,c,...) has a non-local
67 // * There are no other filters
69 // (If opts doesn't indicate a federation-wide list query, fn is just
70 // called once with the local backend.)
72 // fn is called more than once only if the query meets the following
81 // * Each filter must be either "uuid = ..." or "uuid in [...]".
83 // * The maximum possible response size (total number of objects that
84 // could potentially be matched by all of the specified filters)
85 // exceeds the local cluster's response page size limit.
87 // If the query involves multiple backends but doesn't meet these
88 // restrictions, an error is returned without calling fn.
90 // Thus, the caller can assume that either:
92 // * splitListRequest() returns an error, or
94 // * fn is called exactly once, or
96 // * fn is called more than once, with options that satisfy the above
99 // Each call to fn indicates a single (local or remote) backend and a
100 // corresponding options argument suitable for sending to that
102 func (conn *Conn) splitListRequest(ctx context.Context, opts arvados.ListOptions, fn func(context.Context, string, arvados.API, arvados.ListOptions) ([]string, error)) error {
104 var matchAllFilters map[string]bool
105 for _, f := range opts.Filters {
106 matchThisFilter := map[string]bool{}
107 if f.Attr != "uuid" {
111 if f.Operator == "=" {
112 if uuid, ok := f.Operand.(string); ok {
113 matchThisFilter[uuid] = true
115 return httpErrorf(http.StatusBadRequest, "invalid operand type %T for filter %q", f.Operand, f)
117 } else if f.Operator == "in" {
118 if operand, ok := f.Operand.([]interface{}); ok {
119 // skip any elements that aren't
120 // strings (thus can't match a UUID,
121 // thus can't affect the response).
122 for _, v := range operand {
123 if uuid, ok := v.(string); ok {
124 matchThisFilter[uuid] = true
127 } else if strings, ok := f.Operand.([]string); ok {
128 for _, uuid := range strings {
129 matchThisFilter[uuid] = true
132 return httpErrorf(http.StatusBadRequest, "invalid operand type %T in filter %q", f.Operand, f)
139 if matchAllFilters == nil {
140 matchAllFilters = matchThisFilter
142 // Reduce matchAllFilters to the intersection
143 // of matchAllFilters ∩ matchThisFilter.
144 for uuid := range matchAllFilters {
145 if !matchThisFilter[uuid] {
146 delete(matchAllFilters, uuid)
152 if matchAllFilters == nil {
153 // Not filtering by UUID at all; just query the local
155 _, err := fn(ctx, conn.cluster.ClusterID, conn.local, opts)
159 // Collate UUIDs in matchAllFilters by remote cluster ID --
160 // e.g., todoByRemote["aaaaa"]["aaaaa-4zz18-000000000000000"]
161 // will be true -- and count the total number of UUIDs we're
162 // filtering on, so we can compare it to our max page size
165 todoByRemote := map[string]map[string]bool{}
166 for uuid := range matchAllFilters {
168 // Cannot match anything, just drop it
170 if todoByRemote[uuid[:5]] == nil {
171 todoByRemote[uuid[:5]] = map[string]bool{}
173 todoByRemote[uuid[:5]][uuid] = true
178 if len(todoByRemote) > 1 {
180 return httpErrorf(http.StatusBadRequest, "cannot execute federated list query: each filter must be either 'uuid = ...' or 'uuid in [...]'")
182 if opts.Count != "none" {
183 return httpErrorf(http.StatusBadRequest, "cannot execute federated list query unless count==\"none\"")
185 if opts.Limit >= 0 || opts.Offset != 0 || len(opts.Order) > 0 {
186 return httpErrorf(http.StatusBadRequest, "cannot execute federated list query with limit, offset, or order parameter")
188 if max := conn.cluster.API.MaxItemsPerResponse; nUUIDs > max {
189 return httpErrorf(http.StatusBadRequest, "cannot execute federated list query because number of UUIDs (%d) exceeds page size limit %d", nUUIDs, max)
191 selectingUUID := false
192 for _, attr := range opts.Select {
197 if opts.Select != nil && !selectingUUID {
198 return httpErrorf(http.StatusBadRequest, "cannot execute federated list query with a select parameter that does not include uuid")
202 ctx, cancel := context.WithCancel(ctx)
204 errs := make(chan error, len(todoByRemote))
205 for clusterID, todo := range todoByRemote {
206 go func(clusterID string, todo map[string]bool) {
207 // This goroutine sends exactly one value to
209 batch := make([]string, 0, len(todo))
210 for uuid := range todo {
211 batch = append(batch, uuid)
214 var backend arvados.API
215 if clusterID == conn.cluster.ClusterID {
217 } else if backend = conn.remotes[clusterID]; backend == nil {
218 errs <- httpErrorf(http.StatusNotFound, "cannot execute federated list query: no proxy available for cluster %q", clusterID)
223 if len(batch) > len(todo) {
224 // Reduce batch to just the todo's
226 for uuid := range todo {
227 batch = append(batch, uuid)
230 remoteOpts.Filters = []arvados.Filter{{"uuid", "in", batch}}
232 done, err := fn(ctx, clusterID, backend, remoteOpts)
238 for _, uuid := range done {
239 if _, ok := todo[uuid]; ok {
245 errs <- httpErrorf(http.StatusBadGateway, "cannot make progress in federated list query: cluster %q returned none of the requested UUIDs", clusterID)
253 // Wait for all goroutines to return, then return the first
254 // non-nil error, if any.
256 for range todoByRemote {
257 if err := <-errs; err != nil && firstErr == nil {
259 // Signal to any remaining fn() calls that
260 // further effort is futile.
267 func httpErrorf(code int, format string, args ...interface{}) error {
268 return httpserver.ErrorWithStatus(fmt.Errorf(format, args...), code)