mirror of https://github.com/knative/client.git
127 lines
3.5 KiB
Go
127 lines
3.5 KiB
Go
// Copyright © 2019 The Knative Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package printers
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
"strings"
|
|
"text/tabwriter"
|
|
)
|
|
|
|
type flusher interface {
|
|
Flush() error
|
|
}
|
|
|
|
func NewBarePrefixWriter(out io.Writer) PrefixWriter {
|
|
return &prefixWriter{out: out, nested: nil, colIndent: 0, spaceIndent: 0}
|
|
}
|
|
|
|
// NewPrefixWriter creates a new PrefixWriter.
|
|
func NewPrefixWriter(out io.Writer) PrefixWriter {
|
|
tabWriter := tabwriter.NewWriter(out, 0, 8, 2, ' ', 0)
|
|
return &prefixWriter{out: tabWriter, nested: nil, colIndent: 0, spaceIndent: 0}
|
|
}
|
|
|
|
// PrefixWriter can write text at various indentation levels.
|
|
type PrefixWriter interface {
|
|
// Write writes text with the specified indentation level.
|
|
Writef(format string, a ...interface{})
|
|
// WriteLine writes an entire line with no indentation level.
|
|
WriteLine(a ...interface{})
|
|
// Write columns with an initial indentation
|
|
WriteCols(cols ...string) PrefixWriter
|
|
// Write columns with an initial indentation and a newline at the end
|
|
WriteColsLn(cols ...string) PrefixWriter
|
|
// Flush forces indentation to be reset.
|
|
Flush() error
|
|
// WriteAttribute writes the attr (as a label) with the given value and returns
|
|
// a PrefixWriter for writing any subattributes.
|
|
WriteAttribute(attr, value string) PrefixWriter
|
|
}
|
|
|
|
// prefixWriter implements PrefixWriter
|
|
type prefixWriter struct {
|
|
out io.Writer
|
|
nested PrefixWriter
|
|
colIndent int
|
|
spaceIndent int
|
|
}
|
|
|
|
var _ PrefixWriter = &prefixWriter{}
|
|
|
|
func (pw *prefixWriter) Writef(format string, a ...interface{}) {
|
|
prefix := ""
|
|
levelSpace := " "
|
|
for i := 0; i < pw.spaceIndent; i++ {
|
|
prefix += levelSpace
|
|
}
|
|
levelTab := "\t"
|
|
for i := 0; i < pw.colIndent; i++ {
|
|
prefix += levelTab
|
|
}
|
|
if pw.nested != nil {
|
|
pw.nested.Writef(prefix+format, a...)
|
|
} else {
|
|
fmt.Fprintf(pw.out, prefix+format, a...)
|
|
}
|
|
}
|
|
|
|
func (pw *prefixWriter) WriteCols(cols ...string) PrefixWriter {
|
|
ss := make([]string, len(cols))
|
|
for i := range cols {
|
|
ss[i] = "%s"
|
|
}
|
|
format := strings.Join(ss, "\t")
|
|
s := make([]interface{}, len(cols))
|
|
for i, v := range cols {
|
|
s[i] = v
|
|
}
|
|
|
|
pw.Writef(format, s...)
|
|
return &prefixWriter{pw.out, pw, 1, 0}
|
|
}
|
|
|
|
// WriteCols writes the columns to the writer and returns a PrefixWriter for
|
|
// writing any further parts of the "record" in the last column.
|
|
func (pw *prefixWriter) WriteColsLn(cols ...string) PrefixWriter {
|
|
ret := pw.WriteCols(cols...)
|
|
pw.WriteLine()
|
|
return ret
|
|
}
|
|
|
|
func (pw *prefixWriter) WriteLine(a ...interface{}) {
|
|
fmt.Fprintln(pw.out, a...)
|
|
}
|
|
|
|
// WriteAttribute writes the attr (as a label) with the given value and returns
|
|
// a PrefixWriter for writing any subattributes.
|
|
func (pw *prefixWriter) WriteAttribute(attr, value string) PrefixWriter {
|
|
pw.WriteColsLn(Label(attr), value)
|
|
return &prefixWriter{pw.out, pw, 0, 1}
|
|
}
|
|
|
|
func (pw *prefixWriter) Flush() error {
|
|
if f, ok := pw.out.(flusher); ok {
|
|
return f.Flush()
|
|
}
|
|
return fmt.Errorf("output stream %v doesn't support Flush", pw.out)
|
|
}
|
|
|
|
// Format label (extracted so that color could be added more easily to all labels)
|
|
func Label(label string) string {
|
|
return label + ":"
|
|
}
|