Command executor

README.md

@@ -52,3 +52,26 @@ SELECT yaml_to_json("hello: world")
 SELECT json_to_yaml('{"hello":"world"}')
 -- hello: world
 ```
+## cmd
+
+`cmd` is a scalar function that expects a single argument (a bash command string) and it will return the results
+
+```sql
+SELECT cmd("echo 'Hello, World'")
+-- Hello, World
+```
+
+## cmd_table
+
+`cmd_table` is a module that takes in a bash string command and an optional delimiter(default "\n") returning a row for each line
+
+| Column          | Type     |
+|-----------------|----------|
+| line_no         | INT      |
+| contents        | TEXT     |
+
+```sql
+SELECT cmd_table("echo 'Hello, World'",' ')
+-- 1 , Hello,
+-- 2 , World
+```

go.mod

@@ -5,8 +5,10 @@ go 1.16
 require (
 	github.com/augmentable-dev/vtab v0.0.0-20210328214525-c302d68997b8
 	github.com/jmoiron/sqlx v1.3.4
+	github.com/kr/pretty v0.1.0 // indirect
 	github.com/mattn/go-sqlite3 v1.14.6
 	go.riyazali.net/sqlite v0.0.0-20210326190148-448ec1ab2454
+	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	sigs.k8s.io/yaml v1.2.0
 )

go.sum

@@ -6,6 +6,11 @@ github.com/go-sql-driver/mysql v1.5.0 h1:ozyZYNQW3x3HtqT1jira07DN2PArx2v7/mN66gG
 github.com/go-sql-driver/mysql v1.5.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
 github.com/jmoiron/sqlx v1.3.4 h1:wv+0IJZfL5z0uZoUjlpKgHkgaFSYD+r9CfrXjEXsO7w=
 github.com/jmoiron/sqlx v1.3.4/go.mod h1:2BljVx/86SuTyjE+aPYlHCTNvZrnJXghYGpNiXLBMCQ=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/lib/pq v1.2.0 h1:LXpIM/LZ5xGFhOpXAQUIMM1HdyqzVYM13zNdjCEEcA0=
 github.com/lib/pq v1.2.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/mattn/go-pointer v0.0.1 h1:n+XhsuGeVO6MEAp7xyEukFINEa+Quek5psIR/ylA6o0=
@@ -14,8 +19,9 @@ github.com/mattn/go-sqlite3 v1.14.6 h1:dNPt6NO46WmLVt2DLNpwczCmdV5boIZ6g/tlDrlRU
 github.com/mattn/go-sqlite3 v1.14.6/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
 go.riyazali.net/sqlite v0.0.0-20210326190148-448ec1ab2454 h1:hhX5XmBE7RzVDdriWQMjQ1Gfx4JE2oC8IGe/YCNEaFQ=
 go.riyazali.net/sqlite v0.0.0-20210326190148-448ec1ab2454/go.mod h1:NNie4T5ol2qbMg7kw1QkXDrcgTeXQgbGxEhn1m4nBu0=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=

internal/cmd_read/cmd_read.go

@@ -0,0 +1,35 @@
+package cmd_read
+
+import (
+	"os/exec"
+
+	"go.riyazali.net/sqlite"
+)
+
+type cmdRead struct{}
+
+func (f *cmdRead) Args() int           { return 1 }
+func (f *cmdRead) Deterministic() bool { return false }
+func (f *cmdRead) Apply(ctx *sqlite.Context, values ...sqlite.Value) {
+	var (
+		command string
+		err     error
+	)
+
+	if len(values) > 0 {
+		command = values[0].Text()
+	}
+	cmd := exec.Command("bash", "-c", command)
+	stdout, err := cmd.Output()
+
+	if err != nil {
+		ctx.ResultError(err)
+	}
+
+	ctx.ResultText(string(stdout))
+}
+
+// New returns a sqlite function for reading the contents of a cmd
+func New() sqlite.Function {
+	return &cmdRead{}
+}

internal/cmd_read/cmd_read_table.go

@@ -0,0 +1,75 @@
+package cmd_read
+
+import (
+	"fmt"
+	"io"
+	"os/exec"
+	"strings"
+
+	"github.com/augmentable-dev/vtab"
+	"go.riyazali.net/sqlite"
+)
+
+type iterCommands struct {
+	command   string
+	delimiter string
+	contents  []string
+	index     int
+}
+
+func (i *iterCommands) Column(c int) (interface{}, error) {
+	switch c {
+	case 0:
+		return i.command, nil
+	case 1:
+		return i.delimiter, nil
+	case 2:
+		return i.index, nil
+	case 3:
+		return i.contents[i.index], nil
+	}
+	return nil, fmt.Errorf("unknown column")
+}
+func (i *iterCommands) Next() (vtab.Row, error) {
+	i.index += 1
+	if i.index >= len(i.contents) {
+		return nil, io.EOF
+	}
+
+	return i, nil
+}
+
+var commandCols = []vtab.Column{
+	{Name: "command", Type: sqlite.SQLITE_TEXT, NotNull: true, Hidden: true, Filters: []sqlite.ConstraintOp{sqlite.INDEX_CONSTRAINT_EQ}},
+	{Name: "delimiter", Type: sqlite.SQLITE_TEXT, NotNull: true, Hidden: true, Filters: []sqlite.ConstraintOp{sqlite.INDEX_CONSTRAINT_EQ}},
+	{Name: "line_no", Type: sqlite.SQLITE_INTEGER},
+	{Name: "results", Type: sqlite.SQLITE_TEXT},
+}
+
+func NewCommandModule() sqlite.Module {
+	return vtab.NewTableFunc("command", commandCols, func(constraints []vtab.Constraint) (vtab.Iterator, error) {
+		var command, delimiter string
+		for _, constraint := range constraints {
+			if constraint.Op == sqlite.INDEX_CONSTRAINT_EQ {
+				switch constraint.ColIndex {
+				case 0:
+					command = constraint.Value.Text()
+				case 1:
+					delimiter = constraint.Value.Text()
+				}
+			}
+		}
+
+		if delimiter == "" {
+			delimiter = "\n"
+		}
+		cmd := exec.Command("bash", "-c", command)
+		stdout, err := cmd.Output()
+		if err != nil {
+			return nil, err
+		}
+		contents := strings.Split(string(stdout), delimiter)
+		iter := &iterCommands{command, delimiter, contents, -1}
+		return iter, nil
+	})
+}

internal/cmd_read/cmd_read_table_test.go

@@ -0,0 +1,77 @@
+package cmd_read
+
+import (
+	"database/sql"
+	"strings"
+	"testing"
+
+	_ "github.com/augmentable-dev/flite/internal/sqlite"
+	"github.com/jmoiron/sqlx"
+	_ "github.com/mattn/go-sqlite3"
+	"go.riyazali.net/sqlite"
+)
+
+func RowContent(rows *sql.Rows) (colCount int, contents [][]string, err error) {
+	columns, err := rows.Columns()
+	if err != nil {
+		return colCount, nil, err
+	}
+
+	colCount = len(columns)
+
+	pointers := make([]interface{}, len(columns))
+	container := make([]sql.NullString, len(columns))
+
+	for i := range pointers {
+		pointers[i] = &container[i]
+	}
+
+	for rows.Next() {
+		err = rows.Scan(pointers...)
+		if err != nil {
+			return colCount, nil, err
+		}
+
+		r := make([]string, len(columns))
+		for i, c := range container {
+			if c.Valid {
+				r[i] = c.String
+			} else {
+				r[i] = "NULL"
+			}
+		}
+		contents = append(contents, r)
+	}
+	return colCount, contents, rows.Err()
+
+}
+
+func TestReadTableCommand(t *testing.T) {
+	commandToExec := "echo Hello World"
+	checkOutput := strings.Split("Hello World", " ")
+	sqlite.Register(func(api *sqlite.ExtensionApi) (sqlite.ErrorCode, error) {
+		if err := api.CreateModule("cmd_table", NewCommandModule(),
+			sqlite.EponymousOnly(true), sqlite.ReadOnly(true)); err != nil {
+			return sqlite.SQLITE_ERROR, err
+		}
+		return sqlite.SQLITE_OK, nil
+	})
+	db, err := sqlx.Open("sqlite3", ":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+	rows, err := db.Query("SELECT * from cmd_table($1 ,' ')", commandToExec)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, content, err := RowContent(rows)
+	for i := 0; i < len(content); i++ {
+		if strings.TrimSpace(content[i][1]) != strings.TrimSpace(checkOutput[i]) {
+			t.Fatalf("expected response: %s, got: %s", checkOutput[i], content[i][1])
+		}
+	}
+	if rows.Err() != nil {
+		t.Fatal(err)
+	}
+}

internal/cmd_read/cmd_read_test.go

@@ -0,0 +1,39 @@
+package cmd_read
+
+import (
+	"strings"
+	"testing"
+
+	_ "github.com/augmentable-dev/flite/internal/sqlite"
+	"github.com/jmoiron/sqlx"
+	_ "github.com/mattn/go-sqlite3"
+	"go.riyazali.net/sqlite"
+)
+
+func TestReadCommand(t *testing.T) {
+	commandToExec := "echo Hello World"
+	sqlite.Register(func(api *sqlite.ExtensionApi) (sqlite.ErrorCode, error) {
+		if err := api.CreateFunction("cmd", New()); err != nil {
+			return sqlite.SQLITE_ERROR, err
+		}
+		return sqlite.SQLITE_OK, nil
+	})
+	db, err := sqlx.Open("sqlite3", ":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+	row := db.QueryRow("SELECT cmd($1)", commandToExec)
+	err = row.Err()
+	if err != nil {
+		t.Fatal(err)
+	}
+	var res string
+	err = row.Scan(&res)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if strings.TrimSpace(res) != "Hello World" {
+		t.Fatalf("expected response: %s, got: %s", "Hello World", res)
+	}
+}

pkg/ext/ext.go

@@ -1,10 +1,12 @@
 package ext
 
 import (
+	"github.com/augmentable-dev/flite/internal/cmd_read"
 	"github.com/augmentable-dev/flite/internal/file_read"
 	"github.com/augmentable-dev/flite/internal/file_split"
 	"github.com/augmentable-dev/flite/internal/http"
 	"github.com/augmentable-dev/flite/internal/yaml"
+
 	_ "github.com/mattn/go-sqlite3"
 	"go.riyazali.net/sqlite"
 )
@@ -15,6 +17,10 @@ func init() {
 			sqlite.EponymousOnly(true), sqlite.ReadOnly(true)); err != nil {
 			return sqlite.SQLITE_ERROR, err
 		}
+		if err := api.CreateModule("cmd_table", cmd_read.NewCommandModule(),
+			sqlite.EponymousOnly(true), sqlite.ReadOnly(true)); err != nil {
+			return sqlite.SQLITE_ERROR, err
+		}
 
 		if err := api.CreateFunction("file_read", file_read.New()); err != nil {
 			return sqlite.SQLITE_ERROR, err
@@ -31,6 +37,9 @@ func init() {
 		if err := api.CreateFunction("http_get", http.NewHTTPGet()); err != nil {
 			return sqlite.SQLITE_ERROR, err
 		}
+		if err := api.CreateFunction("cmd_read", cmd_read.New()); err != nil {
+			return sqlite.SQLITE_ERROR, err
+		}
 
 		return sqlite.SQLITE_OK, nil
 	})