driver_go1.09.go

// +build go1.9,!go1.10

package zipkinsql

import (
	"database/sql"
	"database/sql/driver"

	zipkin "github.com/openzipkin/zipkin-go"
)

var errConnDone = sql.ErrConnDone

// zDriver implements driver.Driver
type zDriver struct {
	parent  driver.Driver
	tracer  *zipkin.Tracer
	options TraceOptions
}

func wrapDriver(d driver.Driver, t *zipkin.Tracer, o TraceOptions) driver.Driver {
	return zDriver{parent: d, tracer: t, options: o}
}

func wrapConn(parent driver.Conn, t *zipkin.Tracer, options TraceOptions) driver.Conn {
	var (
		n, hasNameValueChecker = parent.(driver.NamedValueChecker)
	)
	c := &zConn{parent: parent, tracer: t, options: options}
	if hasNameValueChecker {
		return struct {
			conn
			driver.NamedValueChecker
		}{c, n}
	}
	return c
}

func wrapStmt(stmt driver.Stmt, query string, tracer *zipkin.Tracer, options TraceOptions) driver.Stmt {
	var (
		_, hasExeCtx    = stmt.(driver.StmtExecContext)
		_, hasQryCtx    = stmt.(driver.StmtQueryContext)
		c, hasColConv   = stmt.(driver.ColumnConverter)
		n, hasNamValChk = stmt.(driver.NamedValueChecker)
	)

	s := zStmt{parent: stmt, query: query, tracer: tracer, options: options}
	switch {
	case !hasExeCtx && !hasQryCtx && !hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
		}{s}
	case !hasExeCtx && hasQryCtx && !hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtQueryContext
		}{s, s}
	case hasExeCtx && !hasQryCtx && !hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
		}{s, s}
	case hasExeCtx && hasQryCtx && !hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.StmtQueryContext
		}{s, s, s}
	case !hasExeCtx && !hasQryCtx && hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.ColumnConverter
		}{s, c}
	case !hasExeCtx && hasQryCtx && hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtQueryContext
			driver.ColumnConverter
		}{s, s, c}
	case hasExeCtx && !hasQryCtx && hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.ColumnConverter
		}{s, s, c}
	case hasExeCtx && hasQryCtx && hasColConv && !hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.StmtQueryContext
			driver.ColumnConverter
		}{s, s, s, c}

	case !hasExeCtx && !hasQryCtx && !hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.NamedValueChecker
		}{s, n}
	case !hasExeCtx && hasQryCtx && !hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtQueryContext
			driver.NamedValueChecker
		}{s, s, n}
	case hasExeCtx && !hasQryCtx && !hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.NamedValueChecker
		}{s, s, n}
	case hasExeCtx && hasQryCtx && !hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.StmtQueryContext
			driver.NamedValueChecker
		}{s, s, s, n}
	case !hasExeCtx && !hasQryCtx && hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.ColumnConverter
			driver.NamedValueChecker
		}{s, c, n}
	case !hasExeCtx && hasQryCtx && hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtQueryContext
			driver.ColumnConverter
			driver.NamedValueChecker
		}{s, s, c, n}
	case hasExeCtx && !hasQryCtx && hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.ColumnConverter
			driver.NamedValueChecker
		}{s, s, c, n}
	case hasExeCtx && hasQryCtx && hasColConv && hasNamValChk:
		return struct {
			driver.Stmt
			driver.StmtExecContext
			driver.StmtQueryContext
			driver.ColumnConverter
			driver.NamedValueChecker
		}{s, s, s, c, n}
	}
	panic("unreachable")
}