support partitioned tables in frontend

templates/index.tmpl

@@ -122,10 +122,27 @@ a {
         <a is="theme-toggler"></a>
     </p>
     <p id="about">
-    HELLO. THIS IS A <a href="https://github.com/vilmibm/trunkless">SOFT WARE</a> FOR MAKING <a href="https://en.wikipedia.org/wiki/Cut-up_technique">CUT-UP POETRY</a>. THERE ARE 467,014,991 POSSIBLE LINES YOU MAY SEE. ALL OF THE LINES ARE FROM THE ENGLISH CORPUS OF <a href="https://gutenberg.org">PROJECT GUTERNBERG</a>. SOME MAY BE OBJECTIONABLE AND I'M SORRY. THE AUTHOR OF THIS SOFT WARE IS <a href="https://tilde.town/~vilmibm">~VILMIBM</a>.
+    <div>
+      HELLO. THIS IS A <a href="https://github.com/vilmibm/trunkless">SOFT WARE</a> FOR MAKING <a href="https://en.wikipedia.org/wiki/Cut-up_technique">CUT-UP POETRY</a>. THERE ARE A VARIETY OF CORPORA TO CHOOSE FROM:
+    </div>
+    <ul>
+      <li><code>gutenberg</code>, THE ENTIRE ENGLISH CONTENT OF <a href="https://gutenberg.org">PROJECT GUTENBERG</a>. IT IS UNABRIDGED: BE WARNED.</li>
+    </ul>
+
+    <div>
+      THE AUTHOR OF THIS SOFT WARE IS <a href="https://tilde.town/~vilmibm">~VILMIBM</a>.
+    </div>
     </p>
     <div class="controls">
       <button is="poem-resetter"></button>
+      <form is="corpus-picker" style="display:inline">
+        <label for="corpus-select">corpus:</label>
+        <select name="corpus" id="corpus-select">
+          {{range .Corpora}}
+            <option value="{{.ID}}">{{.Name}} ({{.MaxID}} possible lines)</option>
+          {{end}}
+        </select>
+      </form>
 
       <form is="poem-saver" style="border: 1px solid grey; display:inline; padding:4px;">
         <button class="copy" type="submit">copy</button>

web/web.go

@@ -3,6 +3,7 @@ package web
 import (
 	"context"
 	"crypto/rand"
+	"fmt"
 	"html/template"
 	"log"
 	"math/big"
@@ -26,6 +27,12 @@ type phrase struct {
 	Source source
 }
 
+type corpus struct {
+	ID    string
+	Name  string
+	MaxID *big.Int
+}
+
 func Serve() error {
 	r := gin.Default()
 	r.SetFuncMap(template.FuncMap{
@@ -39,8 +46,65 @@ func Serve() error {
 	r.StaticFile("/main.js", "./web/assets/main.js")
 	r.StaticFile("/html2canvas.min.js", "./web/assets/html2canvas.min.js")
 
-	// TODO use new db functions for id ranges
-	randMax := big.NewInt(db.MaxID)
+	bctx := context.Background()
+
+	pool, err := db.Pool()
+	if err != nil {
+		return fmt.Errorf("db pool failed: %w", err)
+	}
+	defer pool.Close()
+
+	corpora := []corpus{}
+
+	conn, err := db.Connect()
+	if err != nil {
+		return err
+	}
+
+	fmt.Println("gathering max IDs...")
+	rows, err := conn.Query(bctx, "SELECT tablename FROM pg_tables WHERE tablename LIKE '%phrases_%'")
+	if err != nil {
+		return fmt.Errorf("tablename query failed: %w", err)
+	}
+	defer rows.Close()
+	tables := []string{}
+	for rows.Next() {
+		var tablename string
+		err = rows.Scan(&tablename)
+		if err != nil {
+			return err
+		}
+		tables = append(tables, tablename)
+	}
+	rows.Close()
+
+	fmt.Printf("found %d tables\n", len(tables))
+
+	for _, tablename := range tables {
+		fmt.Printf("- %s...", tablename)
+		var maxID int64
+		err = conn.QueryRow(bctx, fmt.Sprintf("SELECT max(id) FROM %s", tablename)).Scan(&maxID)
+		if err != nil {
+			return err
+		}
+		fmt.Printf("%v...", maxID)
+
+		parts := strings.Split(tablename, "_")
+		corpusid := parts[1]
+		var name string
+		err := conn.QueryRow(bctx, "SELECT name FROM corpora WHERE id=$1", corpusid).Scan(&name)
+		if err != nil {
+			return err
+		}
+		fmt.Printf("%s.\n", name)
+		corpora = append(corpora, corpus{
+			ID:    corpusid,
+			Name:  name,
+			MaxID: big.NewInt(maxID),
+		})
+	}
+	conn.Close(bctx)
+	fmt.Println("...done")
 
 	r.HEAD("/", func(c *gin.Context) {
 		c.String(http.StatusOK, "")
@@ -48,39 +112,54 @@ func Serve() error {
 
 	r.GET("/", func(c *gin.Context) {
 		c.HTML(http.StatusOK, "index.tmpl", struct {
-			// TODO handle multiple corpora
-			MaxID int
-		}{db.MaxID})
+			Corpora []corpus
+		}{corpora})
 	})
 
-	// TODO retool this for pg
-
 	r.GET("/line", func(c *gin.Context) {
-		conn, err := db.Connect()
+		conn, err := pool.Acquire(bctx)
 		if err != nil {
 			log.Println(err.Error())
 			c.String(http.StatusInternalServerError, "oh no.")
 			return
 		}
-		defer conn.Close(context.Background())
+		defer conn.Release()
 
-		id, err := rand.Int(rand.Reader, randMax)
+		corpusid := c.DefaultQuery("corpus", "c3d8e9")
+
+		var cpus corpus
+
+		var tablename string
+		for _, corpus := range corpora {
+			if corpus.ID == corpusid {
+				cpus = corpus
+				tablename = fmt.Sprintf("phrases_%s", corpusid)
+			}
+		}
+		if tablename == "" {
+			c.String(http.StatusTeapot, "have some tea :)")
+		}
+
+		id, err := rand.Int(rand.Reader, cpus.MaxID)
 		if err != nil {
 			log.Println(err.Error())
 			c.String(http.StatusInternalServerError, "oh no.")
 			return
 		}
 
-		row := conn.QueryRow(context.Background(), "select p.phrase, s.id, s.name from phrases p join sources s on p.sourceid = s.id where p.id = $1", id.Int64())
 		var p phrase
 		var s source
-		err = row.Scan(&p.Text, &s.ID, &s.Name)
+		err = conn.QueryRow(bctx,
+			fmt.Sprintf(
+				"SELECT p.phrase, s.id, s.name FROM phrases_%s p join sources s on p.sourceid = s.id where p.id = $1", cpus.ID),
+			id.Int64()).Scan(&p.Text, &s.ID, &s.Name)
 		if err != nil {
 			log.Println(err.Error())
 			c.String(http.StatusInternalServerError, "oh no.")
 		}
 		p.Source = s
 		p.ID = id.Int64()
+		conn.Release()
 		c.JSON(http.StatusOK, p)
 	})