From c9e305760d622071e1aaa6d8069cab25366d3b9b Mon Sep 17 00:00:00 2001
From: maximelkin <maxelkin@list.ru>
Date: Tue, 15 Oct 2019 09:23:07 +0300
Subject: [PATCH] Fix oracledb driver v4 support (#3480)

---
 .travis.yml                    |  2 +-
 lib/dialects/oracledb/index.js | 85 ++++++++++++++++++++++++----------
 test/unit/dialects/oracledb.js |  9 ++++
 3 files changed, 71 insertions(+), 25 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index b030361f18..37f98acdc3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -16,7 +16,7 @@ matrix:
       env: TESTSCRIPT=test:everything DB="oracledb mssql mysql mysql2 postgres sqlite3" KNEX_TEST_TIMEOUT=60000
 install:
   - npm i
-  - (echo $DB | grep oracledb) && npm install oracledb@3.1.2 || true
+  - (echo $DB | grep oracledb) && npm install oracledb || true
 
 before_script:
   - npm run db:start
diff --git a/lib/dialects/oracledb/index.js b/lib/dialects/oracledb/index.js
index aed6ded57d..1689f48cdb 100644
--- a/lib/dialects/oracledb/index.js
+++ b/lib/dialects/oracledb/index.js
@@ -131,7 +131,11 @@ Client_Oracledb.prototype.acquireRawConnection = function() {
       };
       const fetchAsync = promisify(function(sql, bindParams, options, cb) {
         options = options || {};
-        options.outFormat = client.driver.OBJECT;
+        options.outFormat =
+          client.driver.OUT_FORMAT_OBJECT || client.driver.OBJECT;
+        if (!options.outFormat) {
+          throw new Error('not found oracledb.outFormat constants');
+        }
         if (options.resultSet) {
           connection.execute(sql, bindParams || [], options, function(
             err,
@@ -202,7 +206,10 @@ Client_Oracledb.prototype.acquireRawConnection = function() {
 
           try {
             for (const lob of lobs) {
-              results.rows[lob.index][lob.key] = await readStream(lob.stream);
+              // todo should be fetchAsString/fetchAsBuffer polyfill only
+              results.rows[lob.index][lob.key] = await lobProcessing(
+                lob.stream
+              );
             }
           } catch (e) {
             await closeResultSet().catch(() => {});
@@ -328,30 +335,29 @@ Client_Oracledb.prototype._query = function(connection, obj) {
   });
 };
 
-// Handle clob
-const readStream = promisify((stream, cb) => {
-  const oracledb = require('oracledb');
-  let data = '';
+/**
+ * @param stream
+ * @param {'string' | 'buffer'} type
+ */
+function readStream(stream, type) {
+  return new Promise((resolve, reject) => {
+    let data = '';
 
-  if (stream.iLob.type === oracledb.CLOB) {
-    stream.setEncoding('utf-8');
-  } else {
-    data = Buffer.alloc(0);
-  }
-  stream.on('error', function(err) {
-    cb(err);
-  });
-  stream.on('data', function(chunk) {
-    if (stream.iLob.type === oracledb.CLOB) {
-      data += chunk;
-    } else {
-      data = Buffer.concat([data, chunk]);
-    }
-  });
-  stream.on('end', function() {
-    cb(null, data);
+    stream.on('error', function(err) {
+      reject(err);
+    });
+    stream.on('data', function(chunk) {
+      if (type === 'string') {
+        data += chunk;
+      } else {
+        data = Buffer.concat([data, chunk]);
+      }
+    });
+    stream.on('end', function() {
+      resolve(data);
+    });
   });
-});
+}
 
 // Process the response as returned from the query.
 Client_Oracledb.prototype.processResponse = function(obj, runner) {
@@ -387,6 +393,37 @@ Client_Oracledb.prototype.processResponse = function(obj, runner) {
   }
 };
 
+const lobProcessing = function(stream) {
+  const oracledb = require('oracledb');
+
+  /**
+   * @type 'string' | 'buffer'
+   */
+  let type;
+
+  if (stream.type) {
+    // v1.2-v4
+    if (stream.type === oracledb.BLOB) {
+      type = 'buffer';
+    } else if (stream.type === oracledb.CLOB) {
+      type = 'string';
+    }
+  } else if (stream.iLob) {
+    // v1
+    if (stream.iLob.type === oracledb.CLOB) {
+      type = 'string';
+    } else if (stream.iLob.type === oracledb.BLOB) {
+      type = 'buffer';
+    }
+  } else {
+    throw new Error('Unrecognized oracledb lob stream type');
+  }
+  if (type === 'string') {
+    stream.setEncoding('utf-8');
+  }
+  return readStream(stream, type);
+};
+
 class Oracledb_Formatter extends Oracle_Formatter {
   // Checks whether a value is a function... if it is, we compile it
   // otherwise we check whether it's a raw
diff --git a/test/unit/dialects/oracledb.js b/test/unit/dialects/oracledb.js
index 3819a24ca9..48aaf427b2 100644
--- a/test/unit/dialects/oracledb.js
+++ b/test/unit/dialects/oracledb.js
@@ -71,6 +71,15 @@ describe('OracleDb parameters', function() {
         });
     });
 
+    it('on clob', function() {
+      return knexClient
+        .raw('select TO_CLOB(\'LONG CONTENT\') as "field" from dual')
+        .then(function(result) {
+          expect(result[0]).to.be.ok;
+          expect(result[0].field).to.be.equal('LONG CONTENT');
+        });
+    });
+
     after(function() {
       return knexClient.destroy();
     });