doc: add examples for custom sql.DB and opencensus

Reviewed By: alexsn

Differential Revision: D17853894

fbshipit-source-id: bdceae27fe12bcf8bde877c51472efe7bd2b2bd6

doc/md/sql-integration.md

@@ -0,0 +1,105 @@
+---
+id: sql-integration
+title: sql.DB Integration
+---
+
+The following examples show how to pass a custom `sql.DB` object to `ent.Client`.
+
+## Configure `sql.DB`
+
+First option:
+
+```go
+package main
+
+import (
+    "time"
+
+    "<your_project>/ent"
+    "github.com/facebookincubator/ent/dialect/sql"
+)
+
+func Open() (*ent.Client, error) {
+    drv, err := sql.Open("mysql", "<mysql-dsn>")
+    if err != nil {
+    	return nil, err
+    }
+    // Get the underlying sql.DB object of the driver.
+    db := drv.DB()
+    db.SetMaxIdleConns(10)
+    db.SetMaxOpenConns(100)
+    db.SetConnMaxLifetime(time.Hour)
+    return ent.NewClient(ent.Driver(drv)), nil
+}
+```
+
+Second option:
+
+```go
+package main
+
+import (
+    "database/sql"
+    "time"
+
+    "<your_project>/ent"
+    entsql "github.com/facebookincubator/ent/dialect/sql"
+)
+
+func Open() (*ent.Client, error) {
+    db, err := sql.Open("mysql", "<mysql-dsn>")
+    if err != nil {
+    	return nil, err
+    }
+    db.SetMaxIdleConns(10)
+    db.SetMaxOpenConns(100)
+    db.SetConnMaxLifetime(time.Hour)
+    // Create an ent.Driver from `db`.
+    drv := entsql.OpenDB("mysql", db)
+    return ent.NewClient(ent.Driver(drv)), nil
+}
+```
+
+## Use Opencensus With MySQL
+
+```go
+package main
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+
+	"<project>/ent"
+	
+	"contrib.go.opencensus.io/integrations/ocsql"
+	"github.com/go-sql-driver/mysql"
+	entsql "github.com/facebookincubator/ent/dialect/sql"
+)
+
+type connector struct {
+	dsn string
+}
+
+func (c connector) Connect(context.Context) (driver.Conn, error) {
+	return c.Driver().Open(c.dsn)
+}
+
+func (connector) Driver() driver.Driver {
+	return ocsql.Wrap(
+		mysql.MySQLDriver{},
+		ocsql.WithAllTraceOptions(),
+		ocsql.WithRowsClose(false),
+		ocsql.WithRowsNext(false),
+		ocsql.WithDisableErrSkip(true),
+	)
+}
+
+// Open new connection and start stats recorder.
+func Open(dsn string) *ent.Client {
+	db := sql.OpenDB(connector{dsn})
+	// Create an ent.Driver from `db`.
+    drv := entsql.OpenDB("mysql", db)
+    return ent.NewClient(ent.Driver(drv))
+}
+```

doc/website/sidebars.json

@@ -23,6 +23,9 @@
     "Migration": [
       "migrate",
       "dialects"
+    ],
+    "Misc": [
+      "sql-integration"
     ]
   }
 }

doc/website/static/css/custom.css

@@ -519,11 +519,6 @@ header > .navigationSlider {
   margin: 0 20px;
 }
 
-.blog .headerWrapper.wrapper header,
-.sideNavVisible .headerWrapper.wrapper header {
-  width: 100vw;
-}
-
 .blog .headerWrapper.wrapper header > a,
 .sideNavVisible .headerWrapper.wrapper header > a {
   width: 288px;