DockerCLI/command/formatter/formatter.go

91 lines
2.3 KiB
Go

package formatter
import (
"bytes"
"fmt"
"io"
"strings"
"text/tabwriter"
"text/template"
"github.com/docker/docker/utils/templates"
)
const (
tableFormatKey = "table"
rawFormatKey = "raw"
defaultQuietFormat = "{{.ID}}"
)
// Context contains information required by the formatter to print the output as desired.
type Context struct {
// Output is the output stream to which the formatted string is written.
Output io.Writer
// Format is used to choose raw, table or custom format for the output.
Format string
// Quiet when set to true will simply print minimal information.
Quiet bool
// Trunc when set to true will truncate the output of certain fields such as Container ID.
Trunc bool
// internal element
table bool
finalFormat string
header string
buffer *bytes.Buffer
}
func (c *Context) preformat() {
c.finalFormat = c.Format
if strings.HasPrefix(c.Format, tableKey) {
c.table = true
c.finalFormat = c.finalFormat[len(tableKey):]
}
c.finalFormat = strings.Trim(c.finalFormat, " ")
r := strings.NewReplacer(`\t`, "\t", `\n`, "\n")
c.finalFormat = r.Replace(c.finalFormat)
}
func (c *Context) parseFormat() (*template.Template, error) {
tmpl, err := templates.Parse(c.finalFormat)
if err != nil {
c.buffer.WriteString(fmt.Sprintf("Template parsing error: %v\n", err))
c.buffer.WriteTo(c.Output)
}
return tmpl, err
}
func (c *Context) postformat(tmpl *template.Template, subContext subContext) {
if c.table {
if len(c.header) == 0 {
// if we still don't have a header, we didn't have any containers so we need to fake it to get the right headers from the template
tmpl.Execute(bytes.NewBufferString(""), subContext)
c.header = subContext.fullHeader()
}
t := tabwriter.NewWriter(c.Output, 20, 1, 3, ' ', 0)
t.Write([]byte(c.header))
t.Write([]byte("\n"))
c.buffer.WriteTo(t)
t.Flush()
} else {
c.buffer.WriteTo(c.Output)
}
}
func (c *Context) contextFormat(tmpl *template.Template, subContext subContext) error {
if err := tmpl.Execute(c.buffer, subContext); err != nil {
c.buffer = bytes.NewBufferString(fmt.Sprintf("Template parsing error: %v\n", err))
c.buffer.WriteTo(c.Output)
return err
}
if c.table && len(c.header) == 0 {
c.header = subContext.fullHeader()
}
c.buffer.WriteString("\n")
return nil
}