Added in-memory sorting to foreignkey.go

Former-commit-id: 10bf89d

Author: joncrlsn

foreignkey.go

@@ -1,26 +1,68 @@
 package main
 
+import "sort"
 import "fmt"
 import "database/sql"
 import "github.com/joncrlsn/pgutil"
 
-// ForeignKeySchema holds a channel streaming foreign key data from one of the databases as well as
+// ==================================
+// ForeignKeyRows definition
+// ==================================
+type ForeignKeyRows []map[string]string
+
+func (slice ForeignKeyRows) Len() int {
+    return len(slice)
+}
+
+func (slice ForeignKeyRows) Less(i, j int) bool {
+    //fmt.Printf("--Less %s:%s with %s:%s", slice[i]["table_name"], slice[i]["column_name"], slice[j]["table_name"], slice[j]["column_name"])
+    if slice[i]["table_name"] == slice[j]["table_name"] {
+        return slice[i]["constraint_def"] < slice[j]["constraint_def"]
+    }
+    return slice[i]["table_name"] < slice[j]["table_name"]
+}
+
+func (slice ForeignKeyRows) Swap(i, j int) {
+    //fmt.Printf("--Swapping %d/%s:%s with %d/%s:%s \n", i, slice[i]["table_name"], slice[i]["index_name"], j, slice[j]["table_name"], slice[j]["index_name"])
+    slice[i], slice[j] = slice[j], slice[i]
+}
+
+// ==================================
+// ForeignKeySchema definition
+// (implements Schema -- defined in pgdiff.go)
+// ==================================
+
+// ForeignKeySchema holds a slice of rows from one of the databases as well as
 // a reference to the current row of data we're viewing.
-//
-// ForeignKeySchema implements the Schema interface defined in pgdiff.go
 type ForeignKeySchema struct {
-	channel chan map[string]string
-	row     map[string]string
+	rows    ForeignKeyRows
+	rowNum  int
 	done    bool
 }
 
+// get returns the value from the current row for the given key
+func (c *ForeignKeySchema) get(key string) string {
+    if c.rowNum >= len(c.rows) {
+        return ""
+    }
+    return c.rows[c.rowNum][key]
+}
+
+// get returns the current row for the given key
+func (c *ForeignKeySchema) getRow() map[string]string {
+    if c.rowNum >= len(c.rows) {
+        return make(map[string]string)
+    }
+    return c.rows[c.rowNum]
+}
+
 // NextRow reads from the channel and tells you if there are (probably) more or not
 func (c *ForeignKeySchema) NextRow() bool {
-	c.row = <-c.channel
-	if len(c.row) == 0 {
-		c.done = true
-	}
-	return !c.done
+    if c.rowNum >= len(c.rows)-1 {
+        c.done = true
+    }
+    c.rowNum = c.rowNum + 1
+    return !c.done
 }
 
 // Compare tells you, in one pass, whether or not the first row matches, is less than, or greater than the second row
@@ -31,28 +73,28 @@ func (c *ForeignKeySchema) Compare(obj interface{}) int {
 		return +999
 	}
 
-	//fmt.Printf("Comparing %s with %s", c.row["table_name"], c2.row["table_name"])
-	val := _compareString(c.row["table_name"], c2.row["table_name"])
+	//fmt.Printf("Comparing %s with %s", c.get("table_name"), c2.get("table_name"))
+	val := _compareString(c.get("table_name"), c2.get("table_name"))
 	if val != 0 {
 		return val
 	}
 
-	val = _compareString(c.row["constraint_def"], c2.row["constraint_def"])
+	val = _compareString(c.get("constraint_def"), c2.get("constraint_def"))
 	return val
 }
 
 // Add returns SQL to add the foreign key
-func (c ForeignKeySchema) Add() {
-	fmt.Printf("ALTER TABLE %s ADD CONSTRAINT %s %s;\n", c.row["table_name"], c.row["constraint_name"], c.row["constraint_def"])
+func (c *ForeignKeySchema) Add() {
+	fmt.Printf("ALTER TABLE %s ADD CONSTRAINT %s %s;\n", c.get("table_name"), c.get("fk_name"), c.get("constraint_def"))
 }
 
 // Drop returns SQL to drop the foreign key
 func (c ForeignKeySchema) Drop() {
-	fmt.Printf("ALTER TABLE %s DROP CONSTRAINT %s; -- %s\n", c.row["table_name"], c.row["constraint_name"], c.row["constraint_def"])
+	fmt.Printf("ALTER TABLE %s DROP CONSTRAINT %s; -- %s\n", c.get("table_name"), c.get("fk_name"), c.get("constraint_def"))
 }
 
 // Change handles the case where the table and foreign key name, but the details do not
-func (c ForeignKeySchema) Change(obj interface{}) {
+func (c *ForeignKeySchema) Change(obj interface{}) {
 	c2, ok := obj.(*ForeignKeySchema)
 	if !ok {
 		fmt.Println("Error!!!, change needs a ForeignKeySchema instance", c2)
@@ -65,22 +107,31 @@ func (c ForeignKeySchema) Change(obj interface{}) {
  */
 func compareForeignKeys(conn1 *sql.DB, conn2 *sql.DB) {
 	sql := `
-SELECT c.conname AS constraint_name
-	, c.contype AS constraint_type
+SELECT c.conname AS fk_name
 	, cl.relname AS table_name
 	, pg_catalog.pg_get_constraintdef(c.oid, true) as constraint_def
 FROM pg_catalog.pg_constraint c
 INNER JOIN pg_class AS cl ON (c.conrelid = cl.oid)
-WHERE c.contype = 'f'
-ORDER BY cl.relname::varchar, pg_catalog.pg_get_constraintdef(c.oid, true) COLLATE "C" ASC;
+WHERE c.contype = 'f';
 `
-
 	rowChan1, _ := pgutil.QueryStrings(conn1, sql)
 	rowChan2, _ := pgutil.QueryStrings(conn2, sql)
 
-	// We have to explicitly type this as Schema for some reason
-	var schema1 Schema = &ForeignKeySchema{channel: rowChan1}
-	var schema2 Schema = &ForeignKeySchema{channel: rowChan2}
+    rows1 := make(ForeignKeyRows, 0)
+    for row := range rowChan1 {
+        rows1 = append(rows1, row)
+    }
+    sort.Sort(rows1)
+
+    rows2 := make(ForeignKeyRows, 0)
+    for row := range rowChan2 {
+        rows2 = append(rows2, row)
+    }
+    sort.Sort(rows2)
+
+    // We have to explicitly type this as Schema here for some unknown reason
+    var schema1 Schema = &ForeignKeySchema{rows: rows1, rowNum: -1}
+    var schema2 Schema = &ForeignKeySchema{rows: rows2, rowNum: -1}
 
 	// Compare the columns
 	doDiff(schema1, schema2)

index.go

@@ -71,6 +71,7 @@ func (c *IndexSchema) Compare(obj interface{}) int {
 	c2, ok := obj.(*IndexSchema)
 	if !ok {
 		fmt.Println("Error!!!, change needs a IndexSchema instance", c2)
+        return +999
 	}
 
 	if len(c.get("table_name")) == 0 || len(c.get("index_name")) == 0 {