railpack

1package plan2 3import (4	"encoding/json"5	"fmt"6	"strings"7 8	"github.com/invopop/jsonschema"9)10 11type Layer struct {12	Image  string `json:"image,omitempty" jsonschema:"description=The image to use as input"`13	Step   string `json:"step,omitempty" jsonschema:"description=The step to use as input"`14	Local  bool   `json:"local,omitempty" jsonschema:"description=Whether to use local files as input"`15	Spread bool   `json:"spread,omitempty" jsonschema:"description=Whether to spread the input"`16 17	Filter18}19 20func NewStepLayer(stepName string, filter ...Filter) Layer {21	input := Layer{22		Step: stepName,23	}24 25	if len(filter) > 0 {26		input.Include = filter[0].Include27		input.Exclude = filter[0].Exclude28	}29 30	return input31}32 33func NewImageLayer(image string, filter ...Filter) Layer {34	input := Layer{35		Image: image,36	}37 38	if len(filter) > 0 {39		input.Include = filter[0].Include40		input.Exclude = filter[0].Exclude41	}42 43	return input44}45 46func NewLocalLayer() Layer {47	return Layer{48		Local:  true,49		Filter: NewIncludeFilter([]string{"."}),50	}51}52 53func (i Layer) IsEmpty() bool {54	return i.Step == "" && i.Image == "" && !i.Local && !i.Spread55}56 57func (i Layer) IsSpread() bool {58	return i.Spread59}60 61func (i *Layer) String() string {62	bytes, _ := json.Marshal(i)63	return string(bytes)64}65 66func (i *Layer) DisplayName() string {67	include := strings.Join(i.Include, ", ")68 69	if i.Local {70		return fmt.Sprintf("local %s", include)71	}72 73	if i.Spread {74		return fmt.Sprintf("spread %s", include)75	}76 77	if i.Step != "" {78		return fmt.Sprintf("$%s", i.Step)79	}80 81	if i.Image != "" {82		return i.Image83	}84 85	return fmt.Sprintf("input %s", include)86}87 88// Supports two types of inputs:89//90// Object Notation:91//   - Step Layer: {"step": "build", "include": ["src/**/*.go"], "exclude": ["*_test.go"]}92//     References the output of a named build step with optional file filtering93//   - Image Layer: {"image": "golang:1.21", "include": ["."], "exclude": ["tmp"]}94//     Uses a Docker image as input with optional file filtering95//   - Local Layer: {"local": true, "include": ["src"], "exclude": ["node_modules"]}96//     Uses local files from the build context with filtering97//98// String Shortcuts: ".", "...", "$stepname"99func (i *Layer) UnmarshalJSON(data []byte) error {100	// First try normal JSON unmarshal for object notation101	type Alias Layer102	aux := &struct {103		*Alias104	}{105		Alias: (*Alias)(i),106	}107	if err := json.Unmarshal(data, &aux); err == nil {108		return nil109	}110 111	// If object unmarshaling fails, try string shortcuts112	str := string(data)113 114	// Remove quotes from JSON string115	str = strings.Trim(str, "\"")116	switch str {117	case ".":118		// "." represents a local layer with current directory119		*i = NewLocalLayer()120		return nil121	case "...":122		// Creates a spread layer that expands to include all previous layers' files123		*i = Layer{Spread: true}124		return nil125	default:126		// "$stepname" represents a reference to another step127		if after, ok := strings.CutPrefix(str, "$"); ok {128			stepName := after129			*i = NewStepLayer(stepName)130			return nil131		}132		return fmt.Errorf("invalid input format: %s", str)133	}134}135 136func (Layer) JSONSchema() *jsonschema.Schema {137	// Create common schemas for include/exclude138	includeSchema := &jsonschema.Schema{139		Type:        "array",140		Description: "Files or directories to include",141		Items: &jsonschema.Schema{142			Type: "string",143		},144	}145	excludeSchema := &jsonschema.Schema{146		Type:        "array",147		Description: "Files or directories to exclude",148		Items: &jsonschema.Schema{149			Type: "string",150		},151	}152 153	// Step input schema154	stepSchema := &jsonschema.Schema{155		Type:       "object",156		Properties: jsonschema.NewProperties(),157	}158	stepSchema.Properties.Set("step", &jsonschema.Schema{159		Type:        "string",160		Description: "The step to use as input",161	})162	stepSchema.Properties.Set("include", includeSchema)163	stepSchema.Properties.Set("exclude", excludeSchema)164	stepSchema.Required = []string{"step"}165 166	// Image input schema167	imageSchema := &jsonschema.Schema{168		Type:       "object",169		Properties: jsonschema.NewProperties(),170	}171	imageSchema.Properties.Set("image", &jsonschema.Schema{172		Type:        "string",173		Description: "The image to use as input",174	})175	imageSchema.Properties.Set("include", includeSchema)176	imageSchema.Properties.Set("exclude", excludeSchema)177	imageSchema.Required = []string{"image"}178 179	// Local input schema180	localSchema := &jsonschema.Schema{181		Type:       "object",182		Properties: jsonschema.NewProperties(),183	}184	localSchema.Properties.Set("local", &jsonschema.Schema{185		Type:        "boolean",186		Description: "Whether to use local files as input",187	})188	localSchema.Properties.Set("include", includeSchema)189	localSchema.Properties.Set("exclude", excludeSchema)190	localSchema.Required = []string{"local"}191 192	// String input schema193	stringSchema := &jsonschema.Schema{194		Type:        "string",195		Description: "Strings will be parsed and interpreted as an input. Valid formats are: '.', '...', or '$step'",196		Enum:        []any{".", "..."},197	}198 199	availableInputs := []*jsonschema.Schema{stepSchema, imageSchema, localSchema, stringSchema}200 201	return &jsonschema.Schema{202		OneOf: availableInputs,203	}204}205