go-sqlite3/_example/vtable/vtable.go

117 lines
2.3 KiB
Go

package main
import (
"encoding/json"
"fmt"
"io/ioutil"
"net/http"
"github.com/mattn/go-sqlite3"
)
type githubRepo struct {
ID int `json:"id"`
FullName string `json:"full_name"`
Description string `json:"description"`
HTMLURL string `json:"html_url"`
}
type githubModule struct {
}
func (m *githubModule) Create(c *sqlite3.SQLiteConn, args []string) (sqlite3.VTab, error) {
err := c.DeclareVTab(fmt.Sprintf(`
CREATE TABLE %s (
id INT,
full_name TEXT,
description TEXT,
html_url TEXT
)`, args[0]))
if err != nil {
return nil, err
}
return &ghRepoTable{}, nil
}
func (m *githubModule) Connect(c *sqlite3.SQLiteConn, args []string) (sqlite3.VTab, error) {
return m.Create(c, args)
}
func (m *githubModule) DestroyModule() {}
type ghRepoTable struct {
repos []githubRepo
}
func (v *ghRepoTable) Open() (sqlite3.VTabCursor, error) {
resp, err := http.Get("https://api.github.com/repositories")
if err != nil {
return nil, err
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil, err
}
var repos []githubRepo
if err := json.Unmarshal(body, &repos); err != nil {
return nil, err
}
return &ghRepoCursor{0, repos}, nil
}
func (v *ghRepoTable) BestIndex(cst []sqlite3.InfoConstraint, ob []sqlite3.InfoOrderBy) (*sqlite3.IndexResult, error) {
used := make([]bool, len(csts))
return &sqlite3.IndexResult{
IdxNum: 0,
IdxStr: "default",
Used: used,
}, nil
}
func (v *ghRepoTable) Disconnect() error { return nil }
func (v *ghRepoTable) Destroy() error { return nil }
type ghRepoCursor struct {
index int
repos []githubRepo
}
func (vc *ghRepoCursor) Column(c *sqlite3.SQLiteContext, col int) error {
switch col {
case 0:
c.ResultInt(vc.repos[vc.index].ID)
case 1:
c.ResultText(vc.repos[vc.index].FullName)
case 2:
c.ResultText(vc.repos[vc.index].Description)
case 3:
c.ResultText(vc.repos[vc.index].HTMLURL)
}
return nil
}
func (vc *ghRepoCursor) Filter(idxNum int, idxStr string, vals []interface{}) error {
vc.index = 0
return nil
}
func (vc *ghRepoCursor) Next() error {
vc.index++
return nil
}
func (vc *ghRepoCursor) EOF() bool {
return vc.index >= len(vc.repos)
}
func (vc *ghRepoCursor) Rowid() (int64, error) {
return int64(vc.index), nil
}
func (vc *ghRepoCursor) Close() error {
return nil
}