feat: Add CSV imports (#4)

README.md

@@ -15,6 +15,7 @@ This is a Go module for rendering tables in the terminal.
 - :left_right_arrow: Set alignments on a per-column basis, with separate settings for headers/footers
 - :triangular_ruler: Intelligently wrap/pad/measure ANSI coloured input
 - :fire: Support for double-width unicode characters
+- :bar_chart: Load data from CSV files
 
 ## Examples
 
@@ -487,15 +488,55 @@ func main() {
 ┌───────────────────┬────────┬─────────────────┐
 │      System       │ Status │   Last Check    │
 ├───────────────────┼────────┼─────────────────┤
-│ Life Support      │ OK     │ May 13 08:54:29 │
+│ Life Support      │ OK     │ May 13 09:09:30 │
 ├───────────────────┤        ├─────────────────┤
-│ Nuclear Generator │        │ May 13 08:53:29 │
+│ Nuclear Generator │        │ May 13 09:08:30 │
 ├───────────────────┼────────┼─────────────────┤
-│ Weapons Systems   │ FAIL   │ May 13 08:54:29 │
+│ Weapons Systems   │ FAIL   │ May 13 09:09:30 │
 ├───────────────────┼────────┤                 │
 │ Shields           │ OK     │                 │
 └───────────────────┴────────┴─────────────────┘
 
+```
+
+### Example: Load Data From Csv
+```go
+package main
+
+import (
+	"os"
+
+	"github.com/aquasecurity/table"
+)
+
+func main() {
+
+	f, err := os.Open("./_examples/12-load-data-from-csv/data.csv")
+	if err != nil {
+		panic(err)
+	}
+
+	t := table.New(os.Stdout)
+	if err := t.LoadCSV(f, true); err != nil {
+		panic(err)
+	}
+	t.Render()
+}
+
+```
+
+#### Output
+```
+┌────┬────────────┬────────────────────────────────────────────┐
+│ Id │    Date    │                  Message                   │
+├────┼────────────┼────────────────────────────────────────────┤
+│ 1  │ 2022-05-12 │ Hello world!                               │
+├────┼────────────┼────────────────────────────────────────────┤
+│ 2  │ 2022-05-12 │ These messages are loaded from a CSV file. │
+├────┼────────────┼────────────────────────────────────────────┤
+│ 3  │ 2022-05-13 │ Incredible!                                │
+└────┴────────────┴────────────────────────────────────────────┘
+
 ```
 <!--/eg-->
 

_examples/12-load-data-from-csv/data.csv

@@ -0,0 +1,4 @@
+Id,Date,Message
+1,2022-05-12,"Hello world!"
+2,2022-05-12,"These messages are loaded from a CSV file."
+3,2022-05-13,"Incredible!"

_examples/12-load-data-from-csv/main.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"os"
+
+	"github.com/aquasecurity/table"
+)
+
+func main() {
+
+	f, err := os.Open("./_examples/12-load-data-from-csv/data.csv")
+	if err != nil {
+		panic(err)
+	}
+
+	t := table.New(os.Stdout)
+	if err := t.LoadCSV(f, true); err != nil {
+		panic(err)
+	}
+	t.Render()
+}

table.go

@@ -1,10 +1,12 @@
 package table
 
 import (
+	"encoding/csv"
 	"fmt"
-	"github.com/mattn/go-runewidth"
 	"io"
 	"strings"
+
+	"github.com/mattn/go-runewidth"
 )
 
 // Table holds information required to render a table to the terminal
@@ -182,6 +184,32 @@ func (t *Table) AddRows(rows ...[]string) {
 	t.data = append(t.data, rows...)
 }
 
+// LoadCSV loads CSV data from a reader and adds it to the table. Existing rows/headers/footers are retained.
+func (t *Table) LoadCSV(r io.Reader, hasHeaders bool) error {
+	cr := csv.NewReader(r)
+
+	if hasHeaders {
+		headers, err := cr.Read()
+		if err != nil {
+			return err
+		}
+		t.SetHeaders(headers...)
+	}
+
+	for {
+		data, err := cr.Read()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return err
+		}
+		t.AddRow(data...)
+	}
+
+	return nil
+}
+
 func (t *Table) getAlignment(colIndex int, header bool, footer bool) Alignment {
 	switch {
 	case header:

table_test.go

@@ -465,3 +465,30 @@ func Test_Unicode(t *testing.T) {
 └─────────────────────────────┴───┴───┘
 `, "\n"+builder.String())
 }
+
+func TestCSV(t *testing.T) {
+
+	input := strings.NewReader(`Id,Date,Message
+1,2022-05-12,"Hello world!"
+2,2022-05-12,"These messages are loaded from a CSV file."
+3,2022-05-13,"Incredible!"`)
+
+	builder := &strings.Builder{}
+	table := New(builder)
+	if err := table.LoadCSV(input, true); err != nil {
+		panic(err)
+	}
+	table.Render()
+
+	assert.Equal(t, `
+┌────┬────────────┬────────────────────────────────────────────┐
+│ Id │    Date    │                  Message                   │
+├────┼────────────┼────────────────────────────────────────────┤
+│ 1  │ 2022-05-12 │ Hello world!                               │
+├────┼────────────┼────────────────────────────────────────────┤
+│ 2  │ 2022-05-12 │ These messages are loaded from a CSV file. │
+├────┼────────────┼────────────────────────────────────────────┤
+│ 3  │ 2022-05-13 │ Incredible!                                │
+└────┴────────────┴────────────────────────────────────────────┘
+`, "\n"+builder.String())
+}