From 0cd61093b9cc47e1375b10415175fec16fa9fb99 Mon Sep 17 00:00:00 2001
From: Dan Sosedoff <dan.sosedoff@gmail.com>
Date: Mon, 19 Dec 2022 13:26:13 -0600
Subject: [PATCH] Display empty schemas on the sidebar (#621)

* Display empty schemas on the sidebar
* Add schemas fetching test
* Skip pg_temp schemas
* Exclude pg_temp tables from other queries
---
 pkg/client/client_test.go      |  7 +++
 pkg/statements/sql/objects.sql |  4 +-
 pkg/statements/sql/schemas.sql |  3 ++
 static/js/app.js               | 80 ++++++++++++++++++++++------------
 4 files changed, 63 insertions(+), 31 deletions(-)

diff --git a/pkg/client/client_test.go b/pkg/client/client_test.go
index 252c4db..eaa4209 100644
--- a/pkg/client/client_test.go
+++ b/pkg/client/client_test.go
@@ -234,6 +234,12 @@ func testDatabases(t *testing.T) {
 	assertMatches(t, []string{"booktown", "postgres"}, res)
 }
 
+func testSchemas(t *testing.T) {
+	res, err := testClient.Schemas()
+	assert.NoError(t, err)
+	assert.Equal(t, []string{"public"}, res)
+}
+
 func testObjects(t *testing.T) {
 	res, err := testClient.Objects()
 	objects := ObjectsFromResult(res)
@@ -617,6 +623,7 @@ func TestAll(t *testing.T) {
 	testInfo(t)
 	testActivity(t)
 	testDatabases(t)
+	testSchemas(t)
 	testObjects(t)
 	testTable(t)
 	testTableRows(t)
diff --git a/pkg/statements/sql/objects.sql b/pkg/statements/sql/objects.sql
index d970710..415624e 100644
--- a/pkg/statements/sql/objects.sql
+++ b/pkg/statements/sql/objects.sql
@@ -20,7 +20,7 @@ WITH all_objects AS (
     pg_catalog.pg_namespace n ON n.oid = c.relnamespace
   WHERE
     c.relkind IN ('r','v','m','S','s','')
-    AND n.nspname !~ '^pg_toast'
+    AND n.nspname !~ '^pg_(toast|temp)'
     AND n.nspname NOT IN ('information_schema', 'pg_catalog')
     AND has_schema_privilege(n.nspname, 'USAGE')
 
@@ -38,7 +38,7 @@ WITH all_objects AS (
   JOIN
     pg_catalog.pg_proc p ON p.pronamespace = n.oid
   WHERE
-    n.nspname !~ '^pg_toast'
+    n.nspname !~ '^pg_(toast|temp)'
     AND n.nspname NOT IN ('information_schema', 'pg_catalog')
 )
 SELECT * FROM all_objects
diff --git a/pkg/statements/sql/schemas.sql b/pkg/statements/sql/schemas.sql
index e68c28d..123349c 100644
--- a/pkg/statements/sql/schemas.sql
+++ b/pkg/statements/sql/schemas.sql
@@ -2,5 +2,8 @@ SELECT
   schema_name
 FROM
   information_schema.schemata
+WHERE
+  schema_name NOT IN ('information_schema', 'pg_catalog')
+  AND schema_name !~ '^pg_(toast|temp)'
 ORDER BY
   schema_name ASC
diff --git a/static/js/app.js b/static/js/app.js
index 1b853b8..62213c6 100644
--- a/static/js/app.js
+++ b/static/js/app.js
@@ -86,6 +86,7 @@ function apiCall(method, path, params, cb) {
 
 function getInfo(cb)                        { apiCall("get", "/info", {}, cb); }
 function getConnection(cb)                  { apiCall("get", "/connection", {}, cb); }
+function getSchemas(cb)                     { apiCall("get", "/schemas", {}, cb); }
 function getObjects(cb)                     { apiCall("get", "/objects", {}, cb); }
 function getTables(cb)                      { apiCall("get", "/tables", {}, cb); }
 function getTableRows(table, opts, cb)      { apiCall("get", "/tables/" + table + "/rows", opts, cb); }
@@ -161,44 +162,65 @@ function buildSchemaSection(name, objects) {
 function loadSchemas() {
   $("#objects").html("");
 
-  getObjects(function(data) {
-    if (Object.keys(data).length == 0) {
-      data["public"] = {
-        table: [],
-        view: [],
-        materialized_view: [],
-        function: [],
-        sequence: []
-      };
+  var emptyObjectList = function() {
+    return {
+      table: [],
+      view: [],
+      materialized_view: [],
+      function: [],
+      sequence: []
+    }
+  }
+
+  getSchemas(function(schemasData) {
+    if (schemasData.error) {
+      alert("Error while fetching schemas: " + schemasData.error);
+      return;
     }
 
-    for (schema in data) {
-      $(buildSchemaSection(schema, data[schema])).appendTo("#objects");
-    }
+    getObjects(function(data) {
+      if (data.error) {
+        alert("Error while fetching database objects: " + data.error);
+        return;
+      }
 
-    if (Object.keys(data).length == 1) {
-      $(".schema").addClass("expanded");
-    }
+      if (Object.keys(data).length == 0) {
+        data["public"] = emptyObjectList();
+      }
 
-    // Clear out all autocomplete objects
-    autocompleteObjects = [];
-    for (schema in data) {
-      for (kind in data[schema]) {
-        if (!(kind == "table" || kind == "view" || kind == "materialized_view" || kind == "function")) {
-          continue
+      for (schemaName of schemasData) {
+        // Allow users to see empty schemas if we dont have any objects in them
+        if (!data[schemaName]) {
+          data[schemaName] = emptyObjectList();
         }
 
-        for (item in data[schema][kind]) {
-          autocompleteObjects.push({
-            caption: data[schema][kind][item].name,
-            value: data[schema][kind][item].name,
-            meta: kind
-          });
+        $(buildSchemaSection(schemaName, data[schemaName])).appendTo("#objects");
+      }
+
+      if (Object.keys(data).length == 1) {
+        $(".schema").addClass("expanded");
+      }
+
+      // Clear out all autocomplete objects
+      autocompleteObjects = [];
+      for (schema in data) {
+        for (kind in data[schema]) {
+          if (!(kind == "table" || kind == "view" || kind == "materialized_view" || kind == "function")) {
+            continue
+          }
+
+          for (item in data[schema][kind]) {
+            autocompleteObjects.push({
+              caption: data[schema][kind][item].name,
+              value: data[schema][kind][item].name,
+              meta: kind
+            });
+          }
         }
       }
-    }
 
-    bindContextMenus();
+      bindContextMenus();
+    });
   });
 }