diff options
Diffstat (limited to 'pkg/api/handlers/compat/events.go')
| -rw-r--r-- | pkg/api/handlers/compat/events.go | 154 |
1 files changed, 105 insertions, 49 deletions
diff --git a/pkg/api/handlers/compat/events.go b/pkg/api/handlers/compat/events.go index 5acc94153..9d5cb5045 100644 --- a/pkg/api/handlers/compat/events.go +++ b/pkg/api/handlers/compat/events.go @@ -1,9 +1,10 @@ package compat import ( - "context" + "encoding/json" "fmt" "net/http" + "sync" "github.com/containers/libpod/v2/libpod" "github.com/containers/libpod/v2/libpod/events" @@ -15,77 +16,132 @@ import ( "github.com/sirupsen/logrus" ) +// filtersFromRequests extracts the "filters" parameter from the specified +// http.Request. The paramater can either be a `map[string][]string` as done +// in new versions of Docker and libpod, or a `map[string]map[string]bool` as +// done in older versions of Docker. We have to do a bit of Yoga to support +// both - just as Docker does as well. +// +// Please refer to https://github.com/containers/podman/issues/6899 for some +// background. +func filtersFromRequest(r *http.Request) ([]string, error) { + var ( + compatFilters map[string]map[string]bool + filters map[string][]string + libpodFilters []string + ) + raw := []byte(r.Form.Get("filters")) + + // Backwards compat with older versions of Docker. + if err := json.Unmarshal(raw, &compatFilters); err == nil { + for filterKey, filterMap := range compatFilters { + for filterValue, toAdd := range filterMap { + if toAdd { + libpodFilters = append(libpodFilters, fmt.Sprintf("%s=%s", filterKey, filterValue)) + } + } + } + return libpodFilters, nil + } + + if err := json.Unmarshal(raw, &filters); err != nil { + return nil, err + } + + for filterKey, filterSlice := range filters { + for _, filterValue := range filterSlice { + libpodFilters = append(libpodFilters, fmt.Sprintf("%s=%s", filterKey, filterValue)) + } + } + + return libpodFilters, nil +} + +// NOTE: this endpoint serves both the docker-compatible one and the new libpod +// one. func GetEvents(w http.ResponseWriter, r *http.Request) { var ( - fromStart bool - eventsError error - decoder = r.Context().Value("decoder").(*schema.Decoder) - runtime = r.Context().Value("runtime").(*libpod.Runtime) + fromStart bool + decoder = r.Context().Value("decoder").(*schema.Decoder) + runtime = r.Context().Value("runtime").(*libpod.Runtime) + json = jsoniter.ConfigCompatibleWithStandardLibrary // FIXME: this should happen on the package level ) + // NOTE: the "filters" parameter is extracted separately for backwards + // compat via `fitlerFromRequest()`. query := struct { - Since string `schema:"since"` - Until string `schema:"until"` - Filters map[string][]string `schema:"filters"` - Stream bool `schema:"stream"` + Since string `schema:"since"` + Until string `schema:"until"` + Stream bool `schema:"stream"` }{ Stream: true, } if err := decoder.Decode(&query, r.URL.Query()); err != nil { utils.Error(w, "Failed to parse parameters", http.StatusBadRequest, errors.Wrapf(err, "Failed to parse parameters for %s", r.URL.String())) - } - - var libpodFilters = []string{} - if _, found := r.URL.Query()["filters"]; found { - for k, v := range query.Filters { - libpodFilters = append(libpodFilters, fmt.Sprintf("%s=%s", k, v[0])) - } + return } if len(query.Since) > 0 || len(query.Until) > 0 { fromStart = true } - eventCtx, eventCancel := context.WithCancel(r.Context()) - eventChannel := make(chan *events.Event) - go func() { - readOpts := events.ReadOptions{FromStart: fromStart, Stream: query.Stream, Filters: libpodFilters, EventChannel: eventChannel, Since: query.Since, Until: query.Until} - eventsError = runtime.Events(eventCtx, readOpts) - }() - if eventsError != nil { - utils.InternalServerError(w, eventsError) - eventCancel() - close(eventChannel) + libpodFilters, err := filtersFromRequest(r) + if err != nil { + utils.Error(w, "Failed to parse parameters", http.StatusBadRequest, errors.Wrapf(err, "Failed to parse parameters for %s", r.URL.String())) return } - // If client disappears we need to stop listening for events - go func(done <-chan struct{}) { - <-done - eventCancel() - if _, ok := <-eventChannel; ok { - close(eventChannel) + eventChannel := make(chan *events.Event) + errorChannel := make(chan error) + + // Start reading events. + go func() { + readOpts := events.ReadOptions{ + FromStart: fromStart, + Stream: query.Stream, + Filters: libpodFilters, + EventChannel: eventChannel, + Since: query.Since, + Until: query.Until, } - }(r.Context().Done()) + errorChannel <- runtime.Events(r.Context(), readOpts) + }() - // Headers need to be written out before turning Writer() over to json encoder - w.Header().Set("Content-Type", "application/json") - w.WriteHeader(http.StatusOK) - if flusher, ok := w.(http.Flusher); ok { - flusher.Flush() - } + var coder *jsoniter.Encoder + var writeHeader sync.Once - json := jsoniter.ConfigCompatibleWithStandardLibrary - coder := json.NewEncoder(w) - coder.SetEscapeHTML(true) + for stream := true; stream; stream = query.Stream { + select { + case err := <-errorChannel: + if err != nil { + utils.InternalServerError(w, err) + return + } + case evt := <-eventChannel: + writeHeader.Do(func() { + // Use a sync.Once so that we write the header + // only once. + w.Header().Set("Content-Type", "application/json") + w.WriteHeader(http.StatusOK) + if flusher, ok := w.(http.Flusher); ok { + flusher.Flush() + } + coder = json.NewEncoder(w) + coder.SetEscapeHTML(true) + }) - for event := range eventChannel { - e := entities.ConvertToEntitiesEvent(*event) - if err := coder.Encode(e); err != nil { - logrus.Errorf("unable to write json: %q", err) - } - if flusher, ok := w.(http.Flusher); ok { - flusher.Flush() + if evt == nil { + continue + } + + e := entities.ConvertToEntitiesEvent(*evt) + if err := coder.Encode(e); err != nil { + logrus.Errorf("unable to write json: %q", err) + } + if flusher, ok := w.(http.Flusher); ok { + flusher.Flush() + } } + } } |