feat: support updatable views (fixes #528)

lib/database.js

@@ -222,39 +222,34 @@ Database.prototype.reload = function () {
     }));
   }
 
+  // attach the introspection scripts
+  this.loader.queryFiles = introspectors;
+
   return this.$p.all(initPromises).then(() => {
     // run introspections and flatten the results into a single list of Entities
-    return this.$p.all([{
-      ctor: Writable,
-      loaders: ['tables']
-    }, {
-      ctor: Readable,
-      loaders: ['views']
-    }, {
-      ctor: Executable,
-      loaders: ['functions', 'scripts']
-    }].reduce((promises, defn) => {
-      // attach the introspection scripts
-      this.loader.queryFiles = introspectors;
-
-      // for each ctor + associated loaders:
-      return promises.concat(defn.loaders.map(loader => {
-        // run the loader
-        const loaderFunc = require(`./loader/${loader}`); // eslint-disable-line global-require
-
-        return loaderFunc(this.instance, this.loader).then(loaded => {
-          // then afterwards map whatever it got into objects defined by ctor
-          return loaded.map(obj => {
-            obj = _.extend(obj, this.loader);
-            obj.db = this;
-            obj.path = !obj.schema || obj.schema === this.currentSchema ? obj.name : [obj.schema, obj.name].join('.');
-
-            return new (Function.prototype.bind.apply(defn.ctor, [null, obj]))();
-          });
-        });
-      }));
+    return this.$p.all(['tables', 'views', 'functions', 'scripts'].map(loader => {
+      // first find and execute the loader function
+      const loaderFunc = require(`./loader/${loader}`); // eslint-disable-line global-require
+
+      return loaderFunc(this.instance, this.loader).then(loaded => {
+        // then afterwards map whatever it got into objects defined by ctor
+        return loaded.map(obj => {
+          obj = _.extend(obj, this.loader);
+          obj.db = this;
+          obj.path = !obj.schema || obj.schema === this.currentSchema ? obj.name : [obj.schema, obj.name].join('.');
+          obj.loader = loader;
+
+          if (Object.hasOwnProperty.call(obj, 'is_insertable_into')) {
+            if (obj.is_insertable_into) {
+              return new (Function.prototype.bind.apply(Writable, [null, obj]))();
+            }
+
+            return new (Function.prototype.bind.apply(Readable, [null, obj]))();
+          }
 
-      // return promises.concat(entityLoaders);
+          return new (Function.prototype.bind.apply(Executable, [null, obj]))();
+        });
+      });
     }, [])).then(groupedObjects => {
       return _.flatten(groupedObjects);
     }).then(objs => {
@@ -272,7 +267,7 @@ Database.prototype.reload = function () {
  */
 Database.prototype.listTables = function () {
   return this.objects.reduce((names, obj) => {
-    if (obj instanceof Writable) {
+    if (obj.loader === 'tables') {
       names.push(obj.path);
     }
 
@@ -287,7 +282,7 @@ Database.prototype.listTables = function () {
  */
 Database.prototype.listViews = function () {
   return this.objects.reduce((names, obj) => {
-    if (obj instanceof Readable && !(obj instanceof Writable)) {
+    if (obj.loader === 'views') {
       names.push(obj.path);
     }
 

lib/entity.js

@@ -9,6 +9,7 @@
  * @param {String} spec.name - The entity's name.
  * @param {String} spec.path - Path to the entity, if a file.
  * @param {String} spec.schema - Entity's owning schema, if a database object.
+ * @param {String} spec.loader - Name of the loader that discovered the entity.
  */
 const Entity = function (spec) {
   if (spec.path) {
@@ -20,6 +21,7 @@ const Entity = function (spec) {
   this.schema = spec.schema || spec.db.currentSchema;
   this.name = spec.name;
   this.db = spec.db;
+  this.loader = spec.loader;
 
   // create delimited names now instead of at query time
   this.delimitedName = `"${this.name}"`;

lib/scripts/tables.sql

@@ -15,8 +15,8 @@ SELECT * FROM (
     t.table_name AS name,
     parent.relname AS parent,
     array_agg(DISTINCT kc.column_name::text) FILTER (WHERE kc.column_name IS NOT NULL) AS pk,
-    TRUE AS is_insertable_into,
-    array_agg(DISTINCT c.column_name::text) AS columns
+    array_agg(DISTINCT c.column_name::text) AS columns,
+    TRUE AS is_insertable_into
   FROM information_schema.tables t
   LEFT OUTER JOIN information_schema.table_constraints tc
     ON tc.table_schema = t.table_schema
@@ -51,8 +51,8 @@ SELECT * FROM (
     t.table_name AS name,
     NULL AS parent,
     NULL AS pk,
-    CASE t.is_insertable_into WHEN 'YES' THEN TRUE ELSE FALSE END AS is_insertable_into,
-    array_agg(c.column_name::text) AS columns
+    array_agg(c.column_name::text) AS columns,
+    CASE t.is_insertable_into WHEN 'YES' THEN TRUE ELSE FALSE END AS is_insertable_into
   FROM information_schema.tables t
   JOIN information_schema.columns c
     ON c.table_schema = t.table_schema

lib/scripts/views-legacy.sql

@@ -11,9 +11,23 @@
 --   override blacklisted tables.
 
 SELECT * FROM (
-  SELECT schemaname AS schema, viewname AS name, FALSE AS is_matview
-  FROM pg_views
+  SELECT
+    v.schemaname AS schema,
+    v.viewname AS name,
+    array_agg(DISTINCT c.column_name::text) AS columns,
+    pg_relation_is_updatable(cls.oid::regclass, true) & 8 >= 8 AS is_insertable_into,
+    FALSE AS is_matview
+  FROM pg_views v
+  JOIN pg_catalog.pg_namespace nsp
+    ON nsp.nspname = v.schemaname
+  JOIN pg_catalog.pg_class cls
+    ON cls.relnamespace = nsp.oid
+    AND cls.relname = v.viewname
+  JOIN information_schema.columns c
+    ON c.table_schema = v.schemaname
+    AND c.table_name = v.viewname
   WHERE schemaname <> 'pg_catalog' AND schemaname <> 'information_schema'
+  GROUP BY v.schemaname, v.viewname, cls.oid
 ) views
 WHERE CASE
   WHEN $(whitelist) <> '' THEN

lib/scripts/views.sql

@@ -11,12 +11,43 @@
 --   override blacklisted tables.
 
 SELECT * FROM (
-  SELECT schemaname AS schema, viewname AS name, FALSE AS is_matview
-  FROM pg_views
+  SELECT
+    v.schemaname AS schema,
+    v.viewname AS name,
+    array_agg(DISTINCT c.column_name::text) AS columns,
+    pg_relation_is_updatable(cls.oid::regclass, true) & 8 >= 8 AS is_insertable_into,
+    FALSE AS is_matview
+  FROM pg_views v
+  JOIN pg_catalog.pg_namespace nsp
+    ON nsp.nspname = v.schemaname
+  JOIN pg_catalog.pg_class cls
+    ON cls.relnamespace = nsp.oid
+    AND cls.relname = v.viewname
+  JOIN information_schema.columns c
+    ON c.table_schema = v.schemaname
+    AND c.table_name = v.viewname
   WHERE schemaname <> 'pg_catalog' AND schemaname <> 'information_schema'
+  GROUP BY v.schemaname, v.viewname, cls.oid
+
   UNION
-  SELECT schemaname AS schema, matviewname AS name, TRUE AS is_matview
-  FROM pg_matviews
+
+  SELECT
+    schemaname AS schema,
+    matviewname AS name,
+    array_agg(DISTINCT c.attname::text) AS columns,
+    FALSE AS is_insertable_into,
+    TRUE AS is_matview
+  FROM pg_matviews v
+  JOIN pg_catalog.pg_namespace nsp
+    ON nsp.nspname = v.schemaname
+  JOIN pg_catalog.pg_class cls
+    ON cls.relnamespace = nsp.oid
+    AND cls.relname = v.matviewname
+  JOIN pg_attribute c
+    ON c.attrelid = cls.oid
+    -- ordinary columns have positive attnum
+    AND c.attnum > 0
+  GROUP BY v.schemaname, v.matviewname
 ) views
 WHERE CASE
   WHEN $(whitelist) <> '' THEN