super-graph/psql/insert.go

250 lines
5.0 KiB
Go

package psql
import (
"bytes"
"errors"
"fmt"
"io"
"github.com/dosco/super-graph/jsn"
"github.com/dosco/super-graph/qcode"
)
var zeroPaging = qcode.Paging{}
func (co *Compiler) compileMutation(qc *qcode.QCode, w *bytes.Buffer, vars Variables) (uint32, error) {
if len(qc.Selects) == 0 {
return 0, errors.New("empty query")
}
c := &compilerContext{w, qc.Selects, co}
root := &qc.Selects[0]
ti, err := c.schema.GetTable(root.Table)
if err != nil {
return 0, err
}
c.w.WriteString(`WITH `)
quoted(c.w, ti.Name)
c.w.WriteString(` AS `)
switch root.Action {
case qcode.ActionInsert:
if _, err := c.renderInsert(qc, w, vars, ti); err != nil {
return 0, err
}
case qcode.ActionUpdate:
if _, err := c.renderUpdate(qc, w, vars, ti); err != nil {
return 0, err
}
case qcode.ActionUpsert:
if _, err := c.renderUpsert(qc, w, vars, ti); err != nil {
return 0, err
}
case qcode.ActionDelete:
if _, err := c.renderDelete(qc, w, vars, ti); err != nil {
return 0, err
}
default:
return 0, errors.New("valid mutations are 'insert', 'update', 'upsert' and 'delete'")
}
io.WriteString(c.w, ` RETURNING *) `)
root.Paging = zeroPaging
root.DistinctOn = root.DistinctOn[:]
root.OrderBy = root.OrderBy[:]
root.Where = nil
root.Args = nil
return c.compileQuery(qc, w)
}
func (c *compilerContext) renderInsert(qc *qcode.QCode, w *bytes.Buffer,
vars Variables, ti *DBTableInfo) (uint32, error) {
root := &qc.Selects[0]
insert, ok := vars[root.ActionVar]
if !ok {
return 0, fmt.Errorf("Variable '%s' not defined", root.ActionVar)
}
jt, array, err := jsn.Tree(insert)
if err != nil {
return 0, err
}
c.w.WriteString(`(WITH "input" AS (SELECT {{`)
c.w.WriteString(root.ActionVar)
c.w.WriteString(`}}::json AS j) INSERT INTO `)
quoted(c.w, ti.Name)
io.WriteString(c.w, ` (`)
c.renderInsertUpdateColumns(qc, w, jt, ti)
io.WriteString(c.w, `)`)
c.w.WriteString(` SELECT `)
c.renderInsertUpdateColumns(qc, w, jt, ti)
c.w.WriteString(` FROM input i, `)
if array {
c.w.WriteString(`json_populate_recordset`)
} else {
c.w.WriteString(`json_populate_record`)
}
c.w.WriteString(`(NULL::`)
c.w.WriteString(ti.Name)
c.w.WriteString(`, i.j) t`)
return 0, nil
}
func (c *compilerContext) renderInsertUpdateColumns(qc *qcode.QCode, w *bytes.Buffer,
jt map[string]interface{}, ti *DBTableInfo) (uint32, error) {
i := 0
for _, cn := range ti.ColumnNames {
if _, ok := jt[cn]; !ok {
continue
}
if i != 0 {
io.WriteString(c.w, `, `)
}
c.w.WriteString(cn)
i++
}
return 0, nil
}
func (c *compilerContext) renderUpdate(qc *qcode.QCode, w *bytes.Buffer,
vars Variables, ti *DBTableInfo) (uint32, error) {
root := &qc.Selects[0]
update, ok := vars[root.ActionVar]
if !ok {
return 0, fmt.Errorf("Variable '%s' not defined", root.ActionVar)
}
jt, array, err := jsn.Tree(update)
if err != nil {
return 0, err
}
c.w.WriteString(`(WITH "input" AS (SELECT {{`)
c.w.WriteString(root.ActionVar)
c.w.WriteString(`}}::json AS j) UPDATE `)
quoted(c.w, ti.Name)
io.WriteString(c.w, ` SET (`)
c.renderInsertUpdateColumns(qc, w, jt, ti)
c.w.WriteString(`) = (SELECT `)
c.renderInsertUpdateColumns(qc, w, jt, ti)
c.w.WriteString(` FROM input i, `)
if array {
c.w.WriteString(`json_populate_recordset`)
} else {
c.w.WriteString(`json_populate_record`)
}
c.w.WriteString(`(NULL::`)
c.w.WriteString(ti.Name)
c.w.WriteString(`, i.j) t)`)
io.WriteString(c.w, ` WHERE `)
if err := c.renderWhere(root, ti); err != nil {
return 0, err
}
return 0, nil
}
func (c *compilerContext) renderDelete(qc *qcode.QCode, w *bytes.Buffer,
vars Variables, ti *DBTableInfo) (uint32, error) {
root := &qc.Selects[0]
c.w.WriteString(`(DELETE FROM `)
quoted(c.w, ti.Name)
io.WriteString(c.w, ` WHERE `)
if err := c.renderWhere(root, ti); err != nil {
return 0, err
}
return 0, nil
}
func (c *compilerContext) renderUpsert(qc *qcode.QCode, w *bytes.Buffer,
vars Variables, ti *DBTableInfo) (uint32, error) {
root := &qc.Selects[0]
upsert, ok := vars[root.ActionVar]
if !ok {
return 0, fmt.Errorf("Variable '%s' not defined", root.ActionVar)
}
jt, _, err := jsn.Tree(upsert)
if err != nil {
return 0, err
}
if _, err := c.renderInsert(qc, w, vars, ti); err != nil {
return 0, err
}
c.w.WriteString(` ON CONFLICT DO (`)
i := 0
for _, cn := range ti.ColumnNames {
if _, ok := jt[cn]; !ok {
continue
}
if col, ok := ti.Columns[cn]; !ok || !(col.UniqueKey || col.PrimaryKey) {
continue
}
if i != 0 {
io.WriteString(c.w, `, `)
}
c.w.WriteString(cn)
i++
}
if i == 0 {
c.w.WriteString(ti.PrimaryCol)
}
c.w.WriteString(`) DO `)
c.w.WriteString(`UPDATE `)
io.WriteString(c.w, ` SET `)
i = 0
for _, cn := range ti.ColumnNames {
if _, ok := jt[cn]; !ok {
continue
}
if i != 0 {
io.WriteString(c.w, `, `)
}
c.w.WriteString(cn)
io.WriteString(c.w, ` = EXCLUDED.`)
c.w.WriteString(cn)
i++
}
return 0, nil
}
func quoted(w *bytes.Buffer, identifier string) {
w.WriteString(`"`)
w.WriteString(identifier)
w.WriteString(`"`)
}