package main import ( "reflect" "strconv" "strings" "time" "github.com/containers/image/types" units "github.com/docker/go-units" "github.com/opencontainers/image-spec/specs-go/v1" "github.com/pkg/errors" "github.com/projectatomic/libpod/cmd/podman/formats" "github.com/urfave/cli" ) const createdByTruncLength = 45 // historyTemplateParams stores info about each layer type historyTemplateParams struct { ID string Created string CreatedBy string Size string Comment string } // historyJSONParams is only used when the JSON format is specified, // and is better for data processing from JSON. // historyJSONParams will be populated by data from v1.History and types.BlobInfo, // the members of the struct are the sama data types as their sources. type historyJSONParams struct { ID string `json:"id"` Created *time.Time `json:"created"` CreatedBy string `json:"createdBy"` Size int64 `json:"size"` Comment string `json:"comment"` } // historyOptions stores cli flag values type historyOptions struct { human bool noTrunc bool quiet bool format string } var ( historyFlags = []cli.Flag{ cli.BoolTFlag{ Name: "human, H", Usage: "Display sizes and dates in human readable format", }, cli.BoolFlag{ Name: "no-trunc, notruncate", Usage: "Do not truncate the output", }, cli.BoolFlag{ Name: "quiet, q", Usage: "Display the numeric IDs only", }, cli.StringFlag{ Name: "format", Usage: "Change the output to JSON or a Go template", }, } historyDescription = "Displays the history of an image. The information can be printed out in an easy to read, " + "or user specified format, and can be truncated." historyCommand = cli.Command{ Name: "history", Usage: "Show history of a specified image", Description: historyDescription, Flags: historyFlags, Action: historyCmd, ArgsUsage: "", UseShortOptionHandling: true, } ) func historyCmd(c *cli.Context) error { if err := validateFlags(c, historyFlags); err != nil { return err } runtime, err := getRuntime(c) if err != nil { return errors.Wrapf(err, "could not get runtime") } defer runtime.Shutdown(false) format := genHistoryFormat(c.String("format"), c.Bool("quiet")) args := c.Args() if len(args) == 0 { return errors.Errorf("an image name must be specified") } if len(args) > 1 { return errors.Errorf("podman history takes at most 1 argument") } image, err := runtime.ImageRuntime().NewFromLocal(args[0]) if err != nil { return err } opts := historyOptions{ human: c.BoolT("human"), noTrunc: c.Bool("no-trunc"), quiet: c.Bool("quiet"), format: format, } history, layers, err := image.History(getContext()) if err != nil { return errors.Wrapf(err, "error getting history of image %q", image.InputName) } return generateHistoryOutput(history, layers, image.ID(), opts) } func genHistoryFormat(format string, quiet bool) string { if format != "" { // "\t" from the command line is not being recognized as a tab // replacing the string "\t" to a tab character if the user passes in "\t" return strings.Replace(format, `\t`, "\t", -1) } if quiet { return formats.IDString } return "table {{.ID}}\t{{.Created}}\t{{.CreatedBy}}\t{{.Size}}\t{{.Comment}}\t" } // historyToGeneric makes an empty array of interfaces for output func historyToGeneric(templParams []historyTemplateParams, JSONParams []historyJSONParams) (genericParams []interface{}) { if len(templParams) > 0 { for _, v := range templParams { genericParams = append(genericParams, interface{}(v)) } return } for _, v := range JSONParams { genericParams = append(genericParams, interface{}(v)) } return } // generate the header based on the template provided func (h *historyTemplateParams) headerMap() map[string]string { v := reflect.Indirect(reflect.ValueOf(h)) values := make(map[string]string) for h := 0; h < v.NumField(); h++ { key := v.Type().Field(h).Name value := key values[key] = strings.ToUpper(splitCamelCase(value)) } return values } // getHistorytemplateOutput gets the modified history information to be printed in human readable format func getHistoryTemplateOutput(history []v1.History, layers []types.BlobInfo, imageID string, opts historyOptions) (historyOutput []historyTemplateParams) { var ( outputSize string createdTime string createdBy string count = 1 ) for i := len(history) - 1; i >= 0; i-- { if i != len(history)-1 { imageID = "" } if !opts.noTrunc && i == len(history)-1 { imageID = shortID(imageID) } var size int64 if !history[i].EmptyLayer { size = layers[len(layers)-count].Size count++ } if opts.human { createdTime = units.HumanDuration(time.Since((*history[i].Created))) + " ago" outputSize = units.HumanSize(float64(size)) } else { createdTime = (history[i].Created).Format(time.RFC3339) outputSize = strconv.FormatInt(size, 10) } createdBy = strings.Join(strings.Fields(history[i].CreatedBy), " ") if !opts.noTrunc && len(createdBy) > createdByTruncLength { createdBy = createdBy[:createdByTruncLength-3] + "..." } params := historyTemplateParams{ ID: imageID, Created: createdTime, CreatedBy: createdBy, Size: outputSize, Comment: history[i].Comment, } historyOutput = append(historyOutput, params) } return } // getHistoryJSONOutput returns the history information in its raw form func getHistoryJSONOutput(history []v1.History, layers []types.BlobInfo, imageID string) (historyOutput []historyJSONParams) { count := 1 for i := len(history) - 1; i >= 0; i-- { var size int64 if !history[i].EmptyLayer { size = layers[len(layers)-count].Size count++ } params := historyJSONParams{ ID: imageID, Created: history[i].Created, CreatedBy: history[i].CreatedBy, Size: size, Comment: history[i].Comment, } historyOutput = append(historyOutput, params) } return } // generateHistoryOutput generates the history based on the format given func generateHistoryOutput(history []v1.History, layers []types.BlobInfo, imageID string, opts historyOptions) error { if len(history) == 0 { return nil } var out formats.Writer switch opts.format { case formats.JSONString: historyOutput := getHistoryJSONOutput(history, layers, imageID) out = formats.JSONStructArray{Output: historyToGeneric([]historyTemplateParams{}, historyOutput)} default: historyOutput := getHistoryTemplateOutput(history, layers, imageID, opts) out = formats.StdoutTemplateArray{Output: historyToGeneric(historyOutput, []historyJSONParams{}), Template: opts.format, Fields: historyOutput[0].headerMap()} } return formats.Writer(out).Out() }