From dea93c27d2809cd5a04563d27cf00a8e682884c8 Mon Sep 17 00:00:00 2001 From: Valentin Rothberg Date: Mon, 20 Jul 2020 14:44:05 +0200 Subject: events endpoint: backwards compat to old type The versions Docker that the compat endpoints currently support are using another type for the `filters` parameter than later versions of Docker, which the libpod/events endpoint is also using. To prevent existing deplopyments from breaking while still achieving backward compat, we now support both types for the filters parameter. Tested manually. Fixes: #6899 Signed-off-by: Valentin Rothberg --- pkg/api/handlers/compat/events.go | 70 ++++++++++++++++++++++++++++++--------- 1 file changed, 55 insertions(+), 15 deletions(-) diff --git a/pkg/api/handlers/compat/events.go b/pkg/api/handlers/compat/events.go index 3fc8248d6..9d5cb5045 100644 --- a/pkg/api/handlers/compat/events.go +++ b/pkg/api/handlers/compat/events.go @@ -1,6 +1,7 @@ package compat import ( + "encoding/json" "fmt" "net/http" "sync" @@ -15,6 +16,49 @@ 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 @@ -23,11 +67,12 @@ func GetEvents(w http.ResponseWriter, r *http.Request) { 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, } @@ -36,21 +81,16 @@ func GetEvents(w http.ResponseWriter, r *http.Request) { return } - var libpodFilters = []string{} - if _, found := r.URL.Query()["filters"]; found { - for k, v := range query.Filters { - if len(v) == 0 { - utils.Error(w, "Failed to parse parameters", http.StatusBadRequest, errors.Errorf("empty value for filter %q", k)) - return - } - libpodFilters = append(libpodFilters, fmt.Sprintf("%s=%s", k, v[0])) - } - } - if len(query.Since) > 0 || len(query.Until) > 0 { fromStart = true } + 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 + } + eventChannel := make(chan *events.Event) errorChannel := make(chan error) -- cgit v1.2.3-54-g00ecf