webtry: Only create sqlite3 tables if they don't exist yet.

experimental/webtry/webtry.go

 package main
 
 import (
         "bytes"
         "crypto/md5"
         "database/sql"
         "encoding/base64"
         "encoding/binary"
         "encoding/json"
         "flag"
@@ skipping 220 matching lines @@
                         panic(err)
                 }
         } else {
                 log.Printf("INFO: Failed to find metadata, unable to connect to MySQL server (Expected when running locally): %q\n", err)
                 // Fallback to sqlite for local use.
                 db, err = sql.Open("sqlite3", "./webtry.db")
                 if err != nil {
                         log.Printf("ERROR: Failed to open: %q\n", err)
                         panic(err)
                 }
-                sql := `CREATE TABLE source_images (
+                sql := `CREATE TABLE IF NOT EXISTS source_images (
              id        INTEGER     PRIMARY KEY                NOT NULL,
              image     MEDIUMBLOB  DEFAULT ''                 NOT NULL, -- formatted as a PNG.
              width     INTEGER     DEFAULT 0                  NOT NULL,
              height    INTEGER     DEFAULT 0                  NOT NULL,
              create_ts TIMESTAMP   DEFAULT CURRENT_TIMESTAMP  NOT NULL,
              hidden    INTEGER     DEFAULT 0                  NOT NULL
              )`
                 _, err = db.Exec(sql)
-                log.Printf("Info: status creating sqlite table for sources: %q\n", err)
+                if err != nil {
+                        log.Printf("Info: status creating sqlite table for sources: %q\n", err)
+                }
 
-                sql = `CREATE TABLE webtry (
+                sql = `CREATE TABLE IF NOT EXISTS webtry (
              code               TEXT      DEFAULT ''                 NOT NULL,
              create_ts          TIMESTAMP DEFAULT CURRENT_TIMESTAMP  NOT NULL,
              hash               CHAR(64)  DEFAULT ''                 NOT NULL,
              source_image_id    INTEGER   DEFAULT 0                  NOT NULL,
 
              PRIMARY KEY(hash)
             )`
                 _, err = db.Exec(sql)
-                log.Printf("Info: status creating sqlite table for webtry: %q\n", err)
+                if err != nil {
+                        log.Printf("Info: status creating sqlite table for webtry: %q\n", err)
+                }
 
-                sql = `CREATE TABLE workspace (
+                sql = `CREATE TABLE IF NOT EXISTS workspace (
           name      CHAR(64)  DEFAULT ''                 NOT NULL,
           create_ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP  NOT NULL,
           PRIMARY KEY(name)
         )`
                 _, err = db.Exec(sql)
-                log.Printf("Info: status creating sqlite table for workspace: %q\n", err)
+                if err != nil {
+                        log.Printf("Info: status creating sqlite table for workspace: %q\n", err)
+                }
 
-                sql = `CREATE TABLE workspacetry (
+                sql = `CREATE TABLE IF NOT EXISTS workspacetry (
           name               CHAR(64)  DEFAULT ''                 NOT NULL,
           create_ts          TIMESTAMP DEFAULT CURRENT_TIMESTAMP  NOT NULL,
           hash               CHAR(64)  DEFAULT ''                 NOT NULL,
           hidden             INTEGER   DEFAULT 0                  NOT NULL,
           source_image_id    INTEGER   DEFAULT 0                  NOT NULL,
 
           FOREIGN KEY (name)   REFERENCES workspace(name)
         )`
                 _, err = db.Exec(sql)
-                log.Printf("Info: status creating sqlite table for workspace try: %q\n", err)
+                if err != nil {
+                        log.Printf("Info: status creating sqlite table for workspace try: %q\n", err)
+                }
         }
 
         // Ping the database to keep the connection fresh.
         go func() {
                 c := time.Tick(1 * time.Minute)
                 for _ = range c {
                         if err := db.Ping(); err != nil {
                                 log.Printf("ERROR: Database failed to respond: %q\n", err)
                         }
                 }
@@ skipping 594 matching lines @@
         http.HandleFunc("/sources/", autogzip.HandleFunc(sourcesHandler))
 
         // Resources are served directly
         // TODO add support for caching/etags/gzip
         http.Handle("/res/", autogzip.Handle(http.FileServer(http.Dir("./"))))
 
         // TODO Break out /c/ as it's own handler.
         http.HandleFunc("/", autogzip.HandleFunc(mainHandler))
         log.Fatal(http.ListenAndServe(*port, nil))
 }