From f97738f0c6156434042f3d1959bb1b4332a6ff56 Mon Sep 17 00:00:00 2001
From: Valentin Kuznetsov <vkuznet@gmail.com>
Date: Sun, 6 Dec 2020 13:07:45 -0500
Subject: [PATCH] Add executeNew

---
 dbs/datasets.go | 47 ++++++++++++++++++++++++++++++++++
 dbs/dbs.go      | 68 +++++++++++++++++++++++++++++++++++++++++++++++++
 web/handlers.go | 13 +++++++++-
 3 files changed, 127 insertions(+), 1 deletion(-)

diff --git a/dbs/datasets.go b/dbs/datasets.go
index 10208efc..5549b0d9 100644
--- a/dbs/datasets.go
+++ b/dbs/datasets.go
@@ -3,6 +3,7 @@ package dbs
 import (
 	"database/sql"
 	"fmt"
+	"net/http"
 	"strings"
 )
 
@@ -128,3 +129,49 @@ func (API) DatasetAccessTypes(params Record) []Record {
 	// use generic query API to fetch the results from DB
 	return executeAll(stm+where, args...)
 }
+
+// Datasets API
+func (API) DatasetsNew(params Record, w http.ResponseWriter) error {
+	// variables we'll use in where clause
+	var args []interface{}
+	where := "WHERE "
+
+	// parse detail arugment
+	detail := getSingleValue(params, "detail")
+
+	// parse is_dataset_valid argument
+	isValid := getSingleValue(params, "is_dataset_valid")
+	if isValid == "" {
+		isValid = "1"
+	}
+	where += fmt.Sprintf("D.IS_DATASET_VALID = %s", placeholder("is_dataset_valid"))
+	args = append(args, isValid)
+
+	// parse dataset argument
+	datasets := getValues(params, "dataset")
+	genSQL := ""
+	if len(datasets) > 1 {
+		where += fmt.Sprintf(" AND D.DATASET in (SELECT TOKEN FROM TOKEN_GENERATOR)")
+		var vals []string
+		genSQL, vals = tokens(datasets)
+		for _, d := range vals {
+			args = append(args, d, d, d) // append three values since tokens generates placeholders for them
+		}
+	} else if len(datasets) == 1 {
+		op, val := opVal(datasets[0])
+		where += fmt.Sprintf(" AND D.DATASET %s %s", op, placeholder("dataset"))
+		args = append(args, val)
+	}
+
+	// get SQL statement from static area
+	stm := getSQL("datasets")
+	cols := []string{"dataset_id", "dataset", "prep_id", "xtcrosssection", "creation_date", "create_by", "last_modification_date", "last_modified_by", "primary_ds_name", "primary_ds_type", "processed_ds_name", "data_tier_name", "dataset_access_type", "acquisition_era_name", "processing_version", "physics_group_name"}
+	vals := []interface{}{new(sql.NullInt64), new(sql.NullString), new(sql.NullString), new(sql.NullFloat64), new(sql.NullInt64), new(sql.NullString), new(sql.NullInt64), new(sql.NullString), new(sql.NullString), new(sql.NullString), new(sql.NullString), new(sql.NullString), new(sql.NullString), new(sql.NullString), new(sql.NullInt64), new(sql.NullString)}
+	if strings.ToLower(detail) != "true" {
+		stm = getSQL("datasets_short")
+		cols = []string{"dataset"}
+		vals = []interface{}{new(sql.NullString)}
+	}
+	// use generic query API to fetch the results from DB
+	return executeNew(w, genSQL+stm+where, cols, vals, args...)
+}
diff --git a/dbs/dbs.go b/dbs/dbs.go
index bc55fdb1..27bfa603 100644
--- a/dbs/dbs.go
+++ b/dbs/dbs.go
@@ -5,6 +5,7 @@ package dbs
 import (
 	"database/sql"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"log"
@@ -342,3 +343,70 @@ func errorRecord(msg string) []Record {
 	out = append(out, erec)
 	return out
 }
+
+// similar to executeAll function but it takes explicit set of columns and values
+func executeNew(w http.ResponseWriter, stm string, cols []string, vals []interface{}, args ...interface{}) error {
+	enc := json.NewEncoder(w)
+
+	if utils.VERBOSE > 1 {
+		log.Println(stm, args)
+	}
+	tx, err := DB.Begin()
+	if err != nil {
+		msg := fmt.Sprintf("unable to obtain transaction %v", err)
+		return errors.New(msg)
+	}
+	defer tx.Rollback()
+	//     rows, err := DB.Query(stm, args...)
+	rows, err := tx.Query(stm, args...)
+	if err != nil {
+		msg := fmt.Sprintf("DB.Query, query='%s' args='%v' error=%v", stm, args, err)
+		return errors.New(msg)
+	}
+	defer rows.Close()
+
+	// loop over rows
+	for rows.Next() {
+		err := rows.Scan(vals...)
+		if err != nil {
+			msg := fmt.Sprintf("rows.Scan, vals='%v', error=%v", vals, err)
+			return errors.New(msg)
+		}
+		rec := make(Record)
+		for i, _ := range cols {
+			vvv := vals[i]
+			switch val := vvv.(type) {
+			case *sql.NullString:
+				v, e := val.Value()
+				if e == nil {
+					rec[cols[i]] = v
+				}
+			case *sql.NullInt64:
+				v, e := val.Value()
+				if e == nil {
+					rec[cols[i]] = v
+				}
+			case *sql.NullFloat64:
+				v, e := val.Value()
+				if e == nil {
+					rec[cols[i]] = v
+				}
+			case *sql.NullBool:
+				v, e := val.Value()
+				if e == nil {
+					rec[cols[i]] = v
+				}
+			default:
+				rec[cols[i]] = val
+			}
+		}
+		err = enc.Encode(rec)
+		if err != nil {
+			return err
+		}
+	}
+	if err = rows.Err(); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/web/handlers.go b/web/handlers.go
index 6caa8de6..1dff654b 100644
--- a/web/handlers.go
+++ b/web/handlers.go
@@ -156,7 +156,18 @@ func DatatiersHandler(w http.ResponseWriter, r *http.Request) (int, int64, error
 
 // DatasetsHandler
 func DatasetsHandler(w http.ResponseWriter, r *http.Request) (int, int64, error) {
-	return DBSGetHandler(w, r, "datasets")
+	//     return DBSGetHandler(w, r, "datasets")
+	status := http.StatusOK
+	var params dbs.Record
+	for k, v := range r.Form {
+		params[k] = v
+	}
+	var api dbs.API
+	err := api.DatasetsNew(params, w)
+	if err != nil {
+		return http.StatusInternalServerError, 0, err
+	}
+	return status, 0, nil
 }
 
 // BlocksHandler