-
Notifications
You must be signed in to change notification settings - Fork 132
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Initial version of CEL resource expressions.
CEL for Receiver notification filtering This introduces CEL for filtering CEL resources in a Receiver. Users can define a CEL expression that is applied as a filter for resources that are identified for notification. A CEL expression that returns false means that a resource will not be annotated. Signed-off-by: Kevin McDermott <[email protected]>
- Loading branch information
Showing
9 changed files
with
528 additions
and
51 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,172 @@ | ||
| package server | ||
|
|
||
| import ( | ||
| "encoding/json" | ||
| "fmt" | ||
| "mime" | ||
| "net/http" | ||
| "strings" | ||
|
|
||
| "github.com/google/cel-go/cel" | ||
| "github.com/google/cel-go/checker/decls" | ||
| "github.com/google/cel-go/common/types" | ||
| "github.com/google/cel-go/common/types/ref" | ||
| "github.com/google/cel-go/common/types/traits" | ||
| celext "github.com/google/cel-go/ext" | ||
| "sigs.k8s.io/controller-runtime/pkg/client" | ||
| ) | ||
|
|
||
| func newCELEvaluator(expr string, req *http.Request) (resourcePredicate, error) { | ||
| env, err := makeCELEnv() | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
| parsed, issues := env.Parse(expr) | ||
| if issues != nil && issues.Err() != nil { | ||
| return nil, fmt.Errorf("failed to parse expression %v: %w", expr, issues.Err()) | ||
| } | ||
|
|
||
| checked, issues := env.Check(parsed) | ||
| if issues != nil && issues.Err() != nil { | ||
| return nil, fmt.Errorf("expression %v check failed: %w", expr, issues.Err()) | ||
| } | ||
|
|
||
| prg, err := env.Program(checked, cel.EvalOptions(cel.OptOptimize)) | ||
| if err != nil { | ||
| return nil, fmt.Errorf("expression %v failed to create a Program: %w", expr, err) | ||
| } | ||
|
|
||
| body := map[string]any{} | ||
| // Only decodes the body for the expression if the body is JSON. | ||
| // Technically you could generate several resources without any body. | ||
| if isJSONContent(req) { | ||
| if err := json.NewDecoder(req.Body).Decode(&body); err != nil { | ||
| return nil, fmt.Errorf("failed to parse request body as JSON: %s", err) | ||
| } | ||
| } | ||
|
|
||
| return func(obj client.Object) (*bool, error) { | ||
| data, err := clientObjectToMap(obj) | ||
| if err != nil { | ||
| return nil, err | ||
| } | ||
|
|
||
| out, _, err := prg.Eval(map[string]any{ | ||
| "resource": data, | ||
| "request": body, | ||
| }) | ||
| if err != nil { | ||
| return nil, fmt.Errorf("expression %v failed to evaluate: %w", expr, err) | ||
| } | ||
|
|
||
| v, ok := out.(types.Bool) | ||
| if !ok { | ||
| return nil, fmt.Errorf("expression %q did not return a boolean value", expr) | ||
| } | ||
|
|
||
| result := v.Value().(bool) | ||
|
|
||
| return &result, nil | ||
| }, nil | ||
| } | ||
|
|
||
| func makeCELEnv() (*cel.Env, error) { | ||
| mapStrDyn := decls.NewMapType(decls.String, decls.Dyn) | ||
| return cel.NewEnv( | ||
| celext.Strings(), | ||
| celext.Encoders(), | ||
| notifications(), | ||
| cel.Declarations( | ||
| decls.NewVar("resource", mapStrDyn), | ||
| decls.NewVar("request", mapStrDyn), | ||
| )) | ||
| } | ||
|
|
||
| func isJSONContent(r *http.Request) bool { | ||
| contentType := r.Header.Get("Content-type") | ||
| for _, v := range strings.Split(contentType, ",") { | ||
| t, _, err := mime.ParseMediaType(v) | ||
| if err != nil { | ||
| break | ||
| } | ||
| if t == "application/json" { | ||
| return true | ||
| } | ||
| } | ||
|
|
||
| return false | ||
| } | ||
|
|
||
| func notifications() cel.EnvOption { | ||
| r, err := types.NewRegistry() | ||
| if err != nil { | ||
| panic(err) // TODO: Do something better? | ||
| } | ||
|
|
||
| return cel.Lib(¬ificationsLib{registry: r}) | ||
| } | ||
|
|
||
| type notificationsLib struct { | ||
| registry *types.Registry | ||
| } | ||
|
|
||
| // LibraryName implements the SingletonLibrary interface method. | ||
| func (*notificationsLib) LibraryName() string { | ||
| return "flux.notifications.lib" | ||
| } | ||
|
|
||
| // CompileOptions implements the Library interface method. | ||
| func (l *notificationsLib) CompileOptions() []cel.EnvOption { | ||
| listStrDyn := cel.ListType(cel.DynType) | ||
| opts := []cel.EnvOption{ | ||
| cel.Function("first", | ||
| cel.MemberOverload("first_list", []*cel.Type{listStrDyn}, cel.DynType, | ||
| cel.UnaryBinding(listFirst))), | ||
| cel.Function("last", | ||
| cel.MemberOverload("last_list", []*cel.Type{listStrDyn}, cel.DynType, | ||
| cel.UnaryBinding(listLast))), | ||
| } | ||
|
|
||
| return opts | ||
| } | ||
|
|
||
| // ProgramOptions implements the Library interface method. | ||
| func (*notificationsLib) ProgramOptions() []cel.ProgramOption { | ||
| return []cel.ProgramOption{} | ||
| } | ||
|
|
||
| func listLast(val ref.Val) ref.Val { | ||
| l := val.(traits.Lister) | ||
| sz := l.Size().Value().(int64) | ||
|
|
||
| if sz == 0 { | ||
| return types.NullValue | ||
| } | ||
|
|
||
| return l.Get(types.Int(sz - 1)) | ||
| } | ||
|
|
||
| func listFirst(val ref.Val) ref.Val { | ||
| l := val.(traits.Lister) | ||
| sz := l.Size().Value().(int64) | ||
|
|
||
| if sz == 0 { | ||
| return types.NullValue | ||
| } | ||
|
|
||
| return l.Get(types.Int(0)) | ||
| } | ||
|
|
||
| func clientObjectToMap(v client.Object) (map[string]any, error) { | ||
| b, err := json.Marshal(v) | ||
| if err != nil { | ||
| return nil, fmt.Errorf("failed to marshal PartialObjectMetadata from resource for CEL expression: %w", err) | ||
| } | ||
|
|
||
| var result map[string]any | ||
| if err := json.Unmarshal(b, &result); err != nil { | ||
| return nil, fmt.Errorf("failed to unmarshal PartialObjectMetadata from resource for CEL expression: %w", err) | ||
| } | ||
|
|
||
| return result, nil | ||
| } |
Oops, something went wrong.