github.com/insionng/yougam@v0.0.0-20170714101924-2bc18d833463/libraries/pingcap/tidb/util/printer/printer.go (about)

     1  // Copyright 2015 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package printer
    15  
    16  import (
    17  	"bytes"
    18  	"fmt"
    19  )
    20  
    21  // Version information.
    22  var (
    23  	TiDBBuildTS = "None"
    24  	TiDBGitHash = "None"
    25  )
    26  
    27  // PrintTiDBInfo prints the TiDB version information.
    28  func PrintTiDBInfo() {
    29  	fmt.Printf("Welcome to the TiDB.\n")
    30  	fmt.Printf("Version:\n")
    31  	fmt.Printf("Git Commit Hash: %s\n", TiDBGitHash)
    32  	fmt.Printf("UTC Build Time:  %s\n", TiDBBuildTS)
    33  	fmt.Printf("\n")
    34  }
    35  
    36  // checkValidity checks whether cols and every data have the same length.
    37  func checkValidity(cols []string, datas [][]string) bool {
    38  	colLen := len(cols)
    39  	if len(datas) == 0 || colLen == 0 {
    40  		return false
    41  	}
    42  
    43  	for _, data := range datas {
    44  		if colLen != len(data) {
    45  			return false
    46  		}
    47  	}
    48  
    49  	return true
    50  }
    51  
    52  func getMaxColLen(cols []string, datas [][]string) []int {
    53  	maxColLen := make([]int, len(cols))
    54  	for i, col := range cols {
    55  		maxColLen[i] = len(col)
    56  	}
    57  
    58  	for _, data := range datas {
    59  		for i, v := range data {
    60  			if len(v) > maxColLen[i] {
    61  				maxColLen[i] = len(v)
    62  			}
    63  		}
    64  	}
    65  
    66  	return maxColLen
    67  }
    68  
    69  func getPrintDivLine(maxColLen []int) []byte {
    70  	var value []byte
    71  	for _, v := range maxColLen {
    72  		value = append(value, '+')
    73  		value = append(value, bytes.Repeat([]byte{'-'}, v+2)...)
    74  	}
    75  	value = append(value, '+')
    76  	value = append(value, '\n')
    77  	return value
    78  }
    79  
    80  func getPrintCol(cols []string, maxColLen []int) []byte {
    81  	var value []byte
    82  	for i, v := range cols {
    83  		value = append(value, '|')
    84  		value = append(value, ' ')
    85  		value = append(value, []byte(v)...)
    86  		value = append(value, bytes.Repeat([]byte{' '}, maxColLen[i]+1-len(v))...)
    87  	}
    88  	value = append(value, '|')
    89  	value = append(value, '\n')
    90  	return value
    91  }
    92  
    93  func getPrintRow(data []string, maxColLen []int) []byte {
    94  	var value []byte
    95  	for i, v := range data {
    96  		value = append(value, '|')
    97  		value = append(value, ' ')
    98  		value = append(value, []byte(v)...)
    99  		value = append(value, bytes.Repeat([]byte{' '}, maxColLen[i]+1-len(v))...)
   100  	}
   101  	value = append(value, '|')
   102  	value = append(value, '\n')
   103  	return value
   104  }
   105  
   106  func getPrintRows(datas [][]string, maxColLen []int) []byte {
   107  	var value []byte
   108  	for _, data := range datas {
   109  		value = append(value, getPrintRow(data, maxColLen)...)
   110  	}
   111  	return value
   112  }
   113  
   114  // GetPrintResult gets a result with a formatted string.
   115  func GetPrintResult(cols []string, datas [][]string) (string, bool) {
   116  	if !checkValidity(cols, datas) {
   117  		return "", false
   118  	}
   119  
   120  	var value []byte
   121  	maxColLen := getMaxColLen(cols, datas)
   122  
   123  	value = append(value, getPrintDivLine(maxColLen)...)
   124  	value = append(value, getPrintCol(cols, maxColLen)...)
   125  	value = append(value, getPrintDivLine(maxColLen)...)
   126  	value = append(value, getPrintRows(datas, maxColLen)...)
   127  	value = append(value, getPrintDivLine(maxColLen)...)
   128  	return string(value), true
   129  }