Files
narratio/internal/config/pipeline_composition.go

225 lines
7.4 KiB
Go

package config
import (
"fmt"
"os"
"path/filepath"
"strings"
"gitea.maximumdirect.net/eric/narratio/internal/fileops"
"gitea.maximumdirect.net/eric/narratio/internal/pathsafe"
"gopkg.in/yaml.v3"
)
type pipelineResolutionMetadata struct {
rootPath string
imports []string
sources []string
ownership []pipelineFieldOwnership
}
type pipelineFieldOwnership struct {
path string
sources []string
}
type pipelineCompositionEnvelope struct {
imports []string
}
func loadComposedPipeline(path string) (*PipelineConfig, error) {
rootPath, err := filepath.Abs(path)
if err != nil {
return nil, fmt.Errorf("resolve root pipeline path %q: %w", path, err)
}
rootFile, err := os.Open(rootPath)
if err != nil {
return nil, fmt.Errorf("pipeline file %q: open: %w", path, err)
}
rootDocument, parseErr := parseCompositionDocument(rootPath, rootFile)
closeErr := rootFile.Close()
if parseErr != nil {
return nil, parseErr
}
if closeErr != nil {
return nil, fmt.Errorf("pipeline file %q: close: %w", rootPath, closeErr)
}
baseRoot, envelope, err := splitPipelineCompositionEnvelope(rootDocument)
if err != nil {
return nil, err
}
imports, err := loadPipelineImports(rootPath, envelope.imports)
if err != nil {
return nil, err
}
documents := make([]*compositionDocument, 0, len(imports)+1)
documents = append(documents, baseRoot)
for _, imported := range imports {
documents = append(documents, imported.document)
}
merged, err := mergeAdditiveCompositions(documents...)
if err != nil {
return nil, err
}
rendered, err := merged.canonicalYAML()
if err != nil {
return nil, err
}
var cfg PipelineConfig
if err := decodeStrictYAMLFromReader("pipeline", rootPath, strings.NewReader(string(rendered)), &cfg); err != nil {
return nil, fmt.Errorf("assembled pipeline sources %s: %w", formatCompositionSources(merged.sources), err)
}
records, err := merged.semanticRecords()
if err != nil {
return nil, err
}
metadata := &pipelineResolutionMetadata{
rootPath: rootPath,
sources: append([]string(nil), merged.sources...),
}
for _, imported := range imports {
metadata.imports = append(metadata.imports, imported.path)
}
for _, record := range records {
metadata.ownership = append(metadata.ownership, pipelineFieldOwnership{
path: record.Path, sources: append([]string(nil), record.Sources...),
})
}
cfg.resolution = metadata
return &cfg, nil
}
func splitPipelineCompositionEnvelope(document *compositionDocument) (*compositionDocument, pipelineCompositionEnvelope, error) {
if err := validateCompositionDocument(document, "root pipeline"); err != nil {
return nil, pipelineCompositionEnvelope{}, err
}
root := cloneCompositionNode(document.root)
index := compositionFieldIndex(root.fields, "composition")
if index < 0 {
return &compositionDocument{root: root, sources: append([]string(nil), document.sources...)}, pipelineCompositionEnvelope{}, nil
}
envelopeNode := root.fields[index].value
if envelopeNode.kind != yaml.MappingNode {
return nil, pipelineCompositionEnvelope{}, fmt.Errorf(
"configuration source %s at composition: expected a mapping, got %s",
formatCompositionSources(envelopeNode.sources), yamlKindName(envelopeNode.kind),
)
}
var envelope pipelineCompositionEnvelope
for _, field := range envelopeNode.fields {
switch field.key {
case "imports":
if field.value.kind != yaml.SequenceNode {
return nil, pipelineCompositionEnvelope{}, fmt.Errorf(
"configuration source %s at composition.imports: expected a list, got %s",
formatCompositionSources(field.value.sources), yamlKindName(field.value.kind),
)
}
for itemIndex, item := range field.value.items {
if item.kind != yaml.ScalarNode || item.tag != "!!str" {
return nil, pipelineCompositionEnvelope{}, fmt.Errorf(
"configuration source %s at composition.imports[%d]: expected a string path",
formatCompositionSources(item.sources), itemIndex,
)
}
envelope.imports = append(envelope.imports, item.value)
}
default:
return nil, pipelineCompositionEnvelope{}, fmt.Errorf(
"configuration source %s at composition.%s: unknown composition field %q",
formatCompositionSources(field.value.sources), field.key, field.key,
)
}
}
root.fields = append(root.fields[:index], root.fields[index+1:]...)
for fieldIndex := range root.fields {
root.fields[fieldIndex].order = fieldIndex
}
return &compositionDocument{root: root, sources: append([]string(nil), document.sources...)}, envelope, nil
}
type loadedPipelineImport struct {
path string
document *compositionDocument
info os.FileInfo
}
func loadPipelineImports(rootPath string, declared []string) ([]loadedPipelineImport, error) {
if len(declared) == 0 {
return nil, nil
}
rootDir := filepath.Dir(rootPath)
rootInfo, err := os.Stat(rootPath)
if err != nil {
return nil, fmt.Errorf("inspect root pipeline file %q: %w", rootPath, err)
}
seenPaths := make(map[string]int, len(declared))
loaded := make([]loadedPipelineImport, 0, len(declared))
for index, raw := range declared {
if strings.TrimSpace(raw) != raw || raw == "" {
return nil, fmt.Errorf("composition.imports[%d] must be a non-empty path without surrounding whitespace", index)
}
normalized, err := pathsafe.NormalizeRelativeDestination(raw)
if err != nil {
return nil, fmt.Errorf("composition.imports[%d] path %q is invalid: %w", index, raw, err)
}
extension := filepath.Ext(filepath.FromSlash(normalized))
if extension != ".yml" && extension != ".yaml" {
return nil, fmt.Errorf("composition.imports[%d] path %q must use .yml or .yaml", index, raw)
}
if prior, duplicate := seenPaths[normalized]; duplicate {
return nil, fmt.Errorf(
"composition.imports[%d] path %q duplicates composition.imports[%d] after normalization",
index, raw, prior,
)
}
seenPaths[normalized] = index
resolved := filepath.Join(rootDir, filepath.FromSlash(normalized))
if resolved == rootPath {
return nil, fmt.Errorf("composition.imports[%d] path %q imports the root pipeline itself", index, raw)
}
file, err := fileops.OpenConfinedRegularFile(rootDir, normalized)
if err != nil {
return nil, fmt.Errorf("open composition.imports[%d] path %q beneath root pipeline directory: %w", index, raw, err)
}
info, statErr := file.Stat()
if statErr != nil {
_ = file.Close()
return nil, fmt.Errorf("inspect composition.imports[%d] path %q: %w", index, raw, statErr)
}
if os.SameFile(rootInfo, info) {
_ = file.Close()
return nil, fmt.Errorf("composition.imports[%d] path %q imports the root pipeline itself", index, raw)
}
for priorIndex, prior := range loaded {
if os.SameFile(prior.info, info) {
_ = file.Close()
return nil, fmt.Errorf(
"composition.imports[%d] path %q references the same file as composition.imports[%d] %q",
index, raw, priorIndex, declared[priorIndex],
)
}
}
document, parseErr := parseCompositionDocument(resolved, file)
closeErr := file.Close()
if parseErr != nil {
return nil, parseErr
}
if closeErr != nil {
return nil, fmt.Errorf("close composition.imports[%d] path %q: %w", index, raw, closeErr)
}
if compositionFieldIndex(document.root.fields, "composition") >= 0 {
return nil, fmt.Errorf(
"imported configuration source %q declares composition; only the root pipeline may declare composition",
resolved,
)
}
loaded = append(loaded, loadedPipelineImport{path: resolved, document: document, info: info})
}
return loaded, nil
}