change pool.end behavior, add force argument [breaking change, v9?]

packages/pg-pool/index.js

@@ -90,6 +90,7 @@ class Pool extends EventEmitter {
     this._endCallback = undefined
     this.ending = false
     this.ended = false
+    this.force = false
   }
 
   _isFull() {
@@ -102,7 +103,8 @@ class Pool extends EventEmitter {
       this.log('pulse queue ended')
       return
     }
-    if (this.ending) {
+    // remove clients from pool if pool is ending and there are no pending queries or if force is enabled
+    if (this.ending && (!this._pendingQueue.length || this.force)) {
       this.log('pulse queue on ending')
       if (this._idle.length) {
         this._idle.slice().map((item) => {
@@ -370,13 +372,19 @@ class Pool extends EventEmitter {
     return response.result
   }
 
-  end(cb) {
+  // force (Boolean) and cb (Function) are optional
+  end(force, cb) {
+    if (typeof force == 'function') {
+      cb = force
+      force = false
+    }
     this.log('ending')
     if (this.ending) {
       const err = new Error('Called end on pool more than once')
       return cb ? cb(err) : this.Promise.reject(err)
     }
     this.ending = true
+    this.force = force
     const promised = promisify(this.Promise, cb)
     this._endCallback = promised.callback
     this._pulseQueue()

packages/pg-pool/test/ending.js

@@ -37,4 +37,24 @@ describe('pool ending', () => {
       expect(res.rows[0].name).to.equal('brianc')
     })
   )
+
+  it('pool.end() - finish pending queries by default', async () => {
+    const pool = new Pool({ poolSize: 10 }) // pool size 10
+    let completed = 0
+    for (let x = 1; x <= 20; x++) { // queue up 20 queries
+       pool.query('SELECT $1::text as name', ['brianc']).then(() => completed++)
+    }
+    await pool.end() // pool.end()
+    expect(completed).to.equal(19) // all 20 queries finish (only 19 here because bug #2163 the last query callback hasn't run yet)
+  })
+
+  it('pool.end(true) - drop pending queries', async () => {
+    const pool = new Pool({ poolSize: 10 }) // pool size 10
+    let completed = 0
+    for (let x = 1; x <= 20; x++) { // queue up 20 queries
+       pool.query('SELECT $1::text as name', ['brianc']).then(() => completed++)
+    }
+    await pool.end(true) // pool.end(true)
+    expect(completed).to.equal(9) // 10 active queries finish, 10 pending queries get dropped (only 9 here because bug #2163 the last query callback hasn't run yet)
+  })
 })