add ability to wire generated clients to directories

pkg/manifestclient/encoding.go

@@ -0,0 +1,80 @@
+package manifestclient
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+)
+
+func individualFromList(objList *unstructured.UnstructuredList, name string) (*unstructured.Unstructured, error) {
+	individualKind := strings.TrimSuffix(objList.GetKind(), "List")
+
+	for _, obj := range objList.Items {
+		if obj.GetName() != name {
+			continue
+		}
+
+		ret := obj.DeepCopy()
+		ret.SetKind(individualKind)
+		return ret, nil
+	}
+
+	return nil, fmt.Errorf("not found in this list")
+}
+
+func readListFile(contentReader RawReader, path string) (*unstructured.UnstructuredList, error) {
+	content, err := contentReader.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("unable to read %q: %w", path, err)
+	}
+
+	return decodeListObj(content)
+}
+
+func readIndividualFile(contentReader RawReader, path string) (*unstructured.Unstructured, error) {
+	content, err := contentReader.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("unable to read %q: %w", path, err)
+	}
+
+	return decodeIndividualObj(content)
+}
+
+var localScheme = runtime.NewScheme()
+var codecs = serializer.NewCodecFactory(localScheme)
+
+func decodeIndividualObj(content []byte) (*unstructured.Unstructured, error) {
+	obj, _, err := codecs.UniversalDecoder().Decode(content, nil, &unstructured.Unstructured{})
+	if err != nil {
+		return nil, fmt.Errorf("unable to decode: %w", err)
+	}
+	return obj.(*unstructured.Unstructured), nil
+}
+
+func decodeListObj(content []byte) (*unstructured.UnstructuredList, error) {
+	obj, _, err := codecs.UniversalDecoder().Decode(content, nil, &unstructured.UnstructuredList{})
+	if err != nil {
+		return nil, fmt.Errorf("unable to decode: %w", err)
+	}
+	return obj.(*unstructured.UnstructuredList), nil
+}
+
+func serializeIndividualObjToJSON(obj *unstructured.Unstructured) (string, error) {
+	ret, err := json.MarshalIndent(obj.Object, "", "    ")
+	if err != nil {
+		return "", err
+	}
+	return string(ret) + "\n", nil
+}
+
+func serializeListObjToJSON(obj *unstructured.UnstructuredList) (string, error) {
+	ret, err := json.MarshalIndent(obj, "", "    ")
+	if err != nil {
+		return "", err
+	}
+	return string(ret) + "\n", nil
+}

pkg/manifestclient/get.go

@@ -0,0 +1,113 @@
+package manifestclient
+
+import (
+	"errors"
+	"fmt"
+	"io/fs"
+	"path/filepath"
+
+	apirequest "k8s.io/apiserver/pkg/endpoints/request"
+)
+
+// must-gather has a few different ways to store resources
+// 1. cluster-scoped-resource/group/resource/<name>.yaml
+// 2. cluster-scoped-resource/group/resource.yaml
+// 3. namespaces/<namespace>/group/resource/<name>.yaml
+// 4. namespaces/<namespace>/group/resource.yaml
+// we have to choose which to prefer and we should always prefer the #2 if it's available.
+// Keep in mind that to produce a cluster-scoped list of namespaced resources, you can need to navigate many namespaces.
+func (mrt *manifestRoundTripper) get(requestInfo *apirequest.RequestInfo) ([]byte, error) {
+	if len(requestInfo.Name) == 0 {
+		return nil, fmt.Errorf("name required for GET")
+	}
+	if len(requestInfo.Resource) == 0 {
+		return nil, fmt.Errorf("resource required for GET")
+	}
+	requiredAPIVersion := fmt.Sprintf("%s/%s", requestInfo.APIGroup, requestInfo.APIVersion)
+	if len(requestInfo.APIGroup) == 0 {
+		requiredAPIVersion = fmt.Sprintf("%s", requestInfo.APIVersion)
+	}
+
+	individualFilePath := individualFileLocation(requestInfo)
+	individualObj, individualErr := readIndividualFile(mrt.contentReader, individualFilePath)
+	switch {
+	case errors.Is(individualErr, fs.ErrNotExist):
+		// try for the list
+	case individualErr != nil:
+		return nil, fmt.Errorf("unable to read file: %w", individualErr)
+	default:
+		if individualObj.GetAPIVersion() != requiredAPIVersion {
+			return nil, fmt.Errorf("actual version %v does not match request %v", individualObj.GetAPIVersion(), requiredAPIVersion)
+		}
+		ret, err := serializeIndividualObjToJSON(individualObj)
+		if err != nil {
+			return nil, fmt.Errorf("failed to serialize %v: %v", individualFilePath, err)
+		}
+		return []byte(ret), nil
+	}
+
+	listFilePath := listFileLocation(requestInfo)
+	listObj, listErr := readListFile(mrt.contentReader, listFilePath)
+	switch {
+	case errors.Is(listErr, fs.ErrNotExist):
+		// we need this to be a not-found when sent back
+		return nil, newNotFound(requestInfo)
+
+	case listErr != nil:
+		return nil, fmt.Errorf("unable to read file: %w", listErr)
+	default:
+		obj, err := individualFromList(listObj, requestInfo.Name)
+		if obj == nil {
+			return nil, newNotFound(requestInfo)
+		}
+		if obj.GetAPIVersion() != requiredAPIVersion {
+			return nil, fmt.Errorf("actual version %v does not match request %v", obj.GetAPIVersion(), requiredAPIVersion)
+		}
+
+		ret, err := serializeIndividualObjToJSON(obj)
+		if err != nil {
+			return nil, fmt.Errorf("failed to serialize %v: %v", listFilePath, err)
+		}
+		return []byte(ret), nil
+	}
+}
+
+func individualFileLocation(requestInfo *apirequest.RequestInfo) string {
+	fileParts := []string{}
+
+	if len(requestInfo.Namespace) > 0 {
+		fileParts = append(fileParts, "namespaces", requestInfo.Namespace)
+	} else {
+		fileParts = append(fileParts, "cluster-scoped-resources")
+	}
+
+	if len(requestInfo.APIGroup) > 0 {
+		fileParts = append(fileParts, requestInfo.APIGroup)
+	} else {
+		fileParts = append(fileParts, "core")
+	}
+
+	fileParts = append(fileParts, requestInfo.Resource, fmt.Sprintf("%s.yaml", requestInfo.Name))
+
+	return filepath.Join(fileParts...)
+}
+
+func listFileLocation(requestInfo *apirequest.RequestInfo) string {
+	fileParts := []string{}
+
+	if len(requestInfo.Namespace) > 0 {
+		fileParts = append(fileParts, "namespaces", requestInfo.Namespace)
+	} else {
+		fileParts = append(fileParts, "cluster-scoped-resources")
+	}
+
+	if len(requestInfo.APIGroup) > 0 {
+		fileParts = append(fileParts, requestInfo.APIGroup)
+	} else {
+		fileParts = append(fileParts, "core")
+	}
+
+	fileParts = append(fileParts, fmt.Sprintf("%s.yaml", requestInfo.Resource))
+
+	return filepath.Join(fileParts...)
+}

pkg/manifestclient/list.go

@@ -0,0 +1,175 @@
+package manifestclient
+
+import (
+	"errors"
+	"fmt"
+	"io/fs"
+	"path/filepath"
+
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	apirequest "k8s.io/apiserver/pkg/endpoints/request"
+)
+
+// must-gather has a few different ways to store resources
+// 1. cluster-scoped-resource/group/resource/<name>.yaml
+// 2. cluster-scoped-resource/group/resource.yaml
+// 3. namespaces/<namespace>/group/resource/<name>.yaml
+// 4. namespaces/<namespace>/group/resource.yaml
+// we have to choose which to prefer and we should always prefer the #2 if it's available.
+// Keep in mind that to produce a cluster-scoped list of namespaced resources, you can need to navigate many namespaces.
+func (mrt *manifestRoundTripper) list(requestInfo *apirequest.RequestInfo) ([]byte, error) {
+	var retList *unstructured.UnstructuredList
+	possibleListFiles, err := allPossibleListFileLocations(mrt.contentReader, requestInfo)
+	if err != nil {
+		return nil, fmt.Errorf("unable to determine list file locations: %w", err)
+	}
+	for _, listFile := range possibleListFiles {
+		currList, err := readListFile(mrt.contentReader, listFile)
+		switch {
+		case errors.Is(err, fs.ErrNotExist):
+			// do nothing, it's possible, not guaranteed
+			continue
+		case err != nil:
+			return nil, fmt.Errorf("unable to determine read list file %v: %w", listFile, err)
+		}
+
+		if retList == nil {
+			retList = currList
+			continue
+		}
+		for i := range currList.Items {
+			retList.Items = append(retList.Items, currList.Items[i])
+		}
+	}
+	if retList != nil {
+		ret, err := serializeListObjToJSON(retList)
+		if err != nil {
+			return nil, fmt.Errorf("failed to serialize: %v", err)
+		}
+		return []byte(ret), nil
+	}
+
+	retList = &unstructured.UnstructuredList{
+		Object: map[string]interface{}{},
+		Items:  nil,
+	}
+	individualFiles, err := allIndividualFileLocations(mrt.contentReader, requestInfo)
+	if err != nil {
+		return nil, fmt.Errorf("unable to determine individual file locations: %w", err)
+	}
+	for _, individualFile := range individualFiles {
+		currInstance, err := readIndividualFile(mrt.contentReader, individualFile)
+		switch {
+		case errors.Is(err, fs.ErrNotExist):
+			// do nothing, it's possible, not guaranteed
+			continue
+		case err != nil:
+			return nil, fmt.Errorf("unable to determine read list file %v: %w", individualFile, err)
+		}
+
+		retList.Items = append(retList.Items, *currInstance)
+	}
+	if len(retList.Items) > 0 {
+		retList.SetKind(retList.Items[0].GetKind() + "List")
+		retList.SetAPIVersion(retList.Items[0].GetAPIVersion())
+
+		ret, err := serializeListObjToJSON(retList)
+		if err != nil {
+			return nil, fmt.Errorf("failed to serialize: %v", err)
+		}
+		return []byte(ret), nil
+	}
+
+	return nil, fmt.Errorf("unable to read any file so we have no Kind")
+}
+
+func allIndividualFileLocations(contentReader RawReader, requestInfo *apirequest.RequestInfo) ([]string, error) {
+	resourceDirectoryParts := []string{}
+	if len(requestInfo.APIGroup) > 0 {
+		resourceDirectoryParts = append(resourceDirectoryParts, requestInfo.APIGroup)
+	} else {
+		resourceDirectoryParts = append(resourceDirectoryParts, "core")
+	}
+	resourceDirectoryParts = append(resourceDirectoryParts, requestInfo.Resource)
+
+	resourceDirectoriesToCheckForIndividualFiles := []string{}
+	if len(requestInfo.Namespace) > 0 {
+		parts := append([]string{"namespaces", requestInfo.Namespace}, resourceDirectoryParts...)
+		resourceDirectoriesToCheckForIndividualFiles = append(resourceDirectoriesToCheckForIndividualFiles, filepath.Join(parts...))
+
+	} else {
+		clusterParts := append([]string{"cluster-scoped-resources"}, resourceDirectoryParts...)
+		resourceDirectoriesToCheckForIndividualFiles = append(resourceDirectoriesToCheckForIndividualFiles, filepath.Join(clusterParts...))
+
+		namespaces, err := allNamespacesWithData(contentReader)
+		if err != nil {
+			return nil, fmt.Errorf("unable to read namespaces")
+		}
+		for _, ns := range namespaces {
+			nsParts := append([]string{"namespaces", ns}, resourceDirectoryParts...)
+			resourceDirectoriesToCheckForIndividualFiles = append(resourceDirectoriesToCheckForIndividualFiles, filepath.Join(nsParts...))
+		}
+	}
+
+	allIndividualFilePaths := []string{}
+	for _, resourceDirectory := range resourceDirectoriesToCheckForIndividualFiles {
+		individualFiles, err := contentReader.ReadDir(resourceDirectory)
+		switch {
+		case errors.Is(err, fs.ErrNotExist):
+			continue
+		case err != nil:
+			return nil, fmt.Errorf("unable to read resourceDir")
+		}
+
+		for _, curr := range individualFiles {
+			allIndividualFilePaths = append(allIndividualFilePaths, filepath.Join(resourceDirectory, curr.Name()))
+		}
+	}
+
+	return allIndividualFilePaths, nil
+}
+
+func allPossibleListFileLocations(contentReader RawReader, requestInfo *apirequest.RequestInfo) ([]string, error) {
+	resourceListFileParts := []string{}
+	if len(requestInfo.APIGroup) > 0 {
+		resourceListFileParts = append(resourceListFileParts, requestInfo.APIGroup)
+	} else {
+		resourceListFileParts = append(resourceListFileParts, "core")
+	}
+	resourceListFileParts = append(resourceListFileParts, fmt.Sprintf("%s.yaml", requestInfo.Resource))
+
+	allPossibleListFileLocations := []string{}
+	if len(requestInfo.Namespace) > 0 {
+		parts := append([]string{"namespaces", requestInfo.Namespace}, resourceListFileParts...)
+		allPossibleListFileLocations = append(allPossibleListFileLocations, filepath.Join(parts...))
+
+	} else {
+		clusterParts := append([]string{"cluster-scoped-resources"}, resourceListFileParts...)
+		allPossibleListFileLocations = append(allPossibleListFileLocations, filepath.Join(clusterParts...))
+
+		namespaces, err := allNamespacesWithData(contentReader)
+		if err != nil {
+			return nil, fmt.Errorf("unable to read namespaces")
+		}
+		for _, ns := range namespaces {
+			nsParts := append([]string{"namespaces", ns}, resourceListFileParts...)
+			allPossibleListFileLocations = append(allPossibleListFileLocations, filepath.Join(nsParts...))
+		}
+	}
+
+	return allPossibleListFileLocations, nil
+}
+
+func allNamespacesWithData(contentReader RawReader) ([]string, error) {
+	nsDirs, err := contentReader.ReadDir("namespaces")
+	if err != nil {
+		return nil, fmt.Errorf("failed to read allNamespacesWithData: %w", err)
+	}
+
+	ret := []string{}
+	for _, curr := range nsDirs {
+		ret = append(ret, curr.Name())
+	}
+
+	return ret, nil
+}