package formats import ( "encoding/json" "fmt" "os" "strings" "text/tabwriter" "text/template" "bytes" "github.com/ghodss/yaml" "github.com/pkg/errors" ) const ( // JSONString const to save on duplicate variable names JSONString = "json" // IDString const to save on duplicates for Go templates IDString = "{{.ID}}" ) // Writer interface for outputs type Writer interface { Out() error } // JSONStructArray for JSON output type JSONStructArray struct { Output []interface{} } // StdoutTemplateArray for Go template output type StdoutTemplateArray struct { Output []interface{} Template string Fields map[string]string } // JSONStruct for JSON output type JSONStruct struct { Output interface{} } // StdoutTemplate for Go template output type StdoutTemplate struct { Output interface{} Template string Fields map[string]string } // YAMLStruct for YAML output type YAMLStruct struct { Output interface{} } // Out method for JSON Arrays func (j JSONStructArray) Out() error { data, err := json.MarshalIndent(j.Output, "", " ") if err != nil { return err } // JSON returns a byte array with a literal null [110 117 108 108] in it // if it is passed empty data. We used bytes.Compare to see if that is // the case. if diff := bytes.Compare(data, []byte("null")); diff == 0 { data = []byte("[]") } // If the we did get NULL back, we should spit out {} which is // at least valid JSON for the consumer. fmt.Printf("%s\n", data) return nil } // Out method for Go templates func (t StdoutTemplateArray) Out() error { w := tabwriter.NewWriter(os.Stdout, 0, 0, 3, ' ', 0) if strings.HasPrefix(t.Template, "table") { // replace any spaces with tabs in template so that tabwriter can align it t.Template = strings.Replace(strings.TrimSpace(t.Template[5:]), " ", "\t", -1) headerTmpl, err := template.New("header").Funcs(headerFunctions).Parse(t.Template) if err != nil { return errors.Wrapf(err, "Template parsing error") } err = headerTmpl.Execute(w, t.Fields) if err != nil { return err } fmt.Fprintln(w, "") } t.Template = strings.Replace(t.Template, " ", "\t", -1) tmpl, err := template.New("image").Funcs(basicFunctions).Parse(t.Template) if err != nil { return errors.Wrapf(err, "Template parsing error") } for _, img := range t.Output { basicTmpl := tmpl.Funcs(basicFunctions) err = basicTmpl.Execute(w, img) if err != nil { return err } fmt.Fprintln(w, "") } return w.Flush() } // Out method for JSON struct func (j JSONStruct) Out() error { data, err := json.MarshalIndent(j.Output, "", " ") if err != nil { return err } fmt.Printf("%s\n", data) return nil } //Out method for Go templates func (t StdoutTemplate) Out() error { tmpl, err := template.New("image").Parse(t.Template) if err != nil { return errors.Wrapf(err, "template parsing error") } err = tmpl.Execute(os.Stdout, t.Output) if err != nil { return err } fmt.Println() return nil } // Out method for YAML func (y YAMLStruct) Out() error { var buf []byte var err error buf, err = yaml.Marshal(y.Output) if err != nil { return err } fmt.Println(string(buf)) return nil }