fix: PGPool error handling and app.js catch/callback bugs

[arnoldcastro5000]

What

Fixes four confirmed bugs in PGPool.js and app.js that cause
permanent request freezes, memory leaks, unhandled process crashes,
and broken 500 error responses.

Fixes Bug 1 in issue: Greenstand/treetracker-infrastructure#315
Related to issue: Greenstand/treetracker-infrastructure#300

Why

PGPool.js

• A DB error left isFetching[sql] = true permanently, freezing all
  future requests for that SQL string and leaking queued callbacks
• The getQuery() Promise never rejected on DB error — callers hung
  indefinitely with no error signal

app.js

• All 4 route catch blocks referenced undefined error instead of
  caught e, causing a ReferenceError that prevented 500 responses
  from being sent
• throw err inside non-async map.render() and fromString
  callbacks bypassed the outer try/catch, generating unhandled
  exceptions that crash the Node process

Change

PGPool.js

• Adopted Node.js error-first callback convention cb(err, result)
  on both success and error paths
• catch block now resets isFetching[sql] and drains the queue,
  calling each pending callback with the error
• getQuery() consumer updated to handle (err, result) and
  propagate errors via rej(err)

app.js

• fromString callback: replaced throw "failed" with return rej(err)
• Both grid routes: renamed _rej → rej to bring rejector into scope
• All render callbacks: replaced throw err with return rej(err)
• All 4 catch blocks: fixed error → e

Follow-up

• Tests for new error paths in PGPool.js (fetch failure, queue drain)
  and app.js (rej propagation) to be added in a subsequent PR per
  CONTRIBUTING.md testing requirements.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature
• Breaking change
• Documentation update

[arnoldcastro5000]

@dadiorchen for your review.

Fixes Bug 1 in issue: Greenstand/treetracker-infrastructure#315

[arnoldcastro5000]

The 2 stuck pods need to be cleared separately. They are not handled by this PR.

PS D:\git\node-mapnik-1> kubectl get pods -n tile-server
NAME READY STATUS RESTARTS AGE
treetracker-tile-server-76c56645c4-7kbfj 1/1 Running 11 (7h3m ago) 22d
treetracker-tile-server-76c56645c4-cn2pt 0/1 ContainerStatusUnknown 6 (39d ago) 41d
treetracker-tile-server-76c56645c4-slzls 1/1 Running 28 (7h3m ago) 36d
treetracker-tile-server-76c56645c4-z8k82 0/1 ContainerStatusUnknown 6 (39d ago) 41d
PS D:\git\node-mapnik-1>

[arnoldcastro5000]

Hi @dadiorchen , need your comments before I proceed with testing on the dev environment.

[arnoldcastro5000]

hi @dadiorchen , requesting your review.

[arnoldcastro5000]

latest status

arnold@kali:~/projects/greenstand$ kubectl get pods -n tile-server
doctl: 2026/06/18 21:27:58 Using cached credential
NAME                                       READY   STATUS    RESTARTS      AGE
treetracker-tile-server-76c56645c4-7mbdx   1/1     Running   5 (10h ago)   5d17h
treetracker-tile-server-76c56645c4-pgpdf   1/1     Running   5 (10h ago)   5d17h
arnold@kali:~/projects/greenstand$

[dadiorchen]

This is good to me
To Deploy this, please let me know if there is any problem @arnoldcastro5000 because this repo is not a normal application

[github-actions]

🎉 This PR is included in version 4.36.2 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀

[arnoldcastro5000]

initial run failed due to github hard-failing actions v1. correcting build-deploy.yml

[arnoldcastro5000]

workflow run now progressed beyond the build-deploy.yml corrections. error in Dockerfile:

  RUN curl -fsSL https://deb.nodesource.com/setup_14.x | sudo -E bash -
  W: GPG error: https://deb.nodesource.com/node_14.x bionic InRelease: NO_PUBKEY 1655A0AB68576280
  ERROR: failed to build ... exit code: 1

[arnoldcastro5000]

Summary of changes to build-deploy.yml

1. upload-artifact@v1 → v4 because v1 is auto-failed by GitHub
2. download-artifact@v1 → v4 + path: added because v1 auto-failed; path: restores the image-tag-${sha}/ folder the downstream cat reads

Summary of changes to Dockerfile

1. NodeSource setup_14.x → direct nodejs.org tarball because NodeSource Node 14 repo's GPG key is dead; tarball keeps Node 14, no APT repo

  .github/workflows/build-deploy.yml (2 hunks)

  --- a/.github/workflows/build-deploy.yml
  +++ b/.github/workflows/build-deploy.yml
  @@ -61,7 +61,7 @@
       - name: persist tag name
  -      uses: actions/upload-artifact@v1
  +      uses: actions/upload-artifact@v4
         with:
           name: image-tag-${{github.sha}}
           path: image-tag
  @@ -83,9 +83,10 @@
       - name: Download tag name
  -      uses: actions/download-artifact@v1
  +      uses: actions/download-artifact@v4
         with:
           name: image-tag-${{github.sha}}
  +        path: image-tag-${{github.sha}}

  Dockerfile (1 hunk)

  --- a/Dockerfile
  +++ b/Dockerfile
  @@ -7,7 +7,7 @@
   #TODO We should build the tile2 image from node 14 alpine
  -RUN curl -fsSL https://deb.nodesource.com/setup_14.x | sudo -E bash -
  -RUN sudo apt-get install -y nodejs
  +RUN curl -fsSL https://nodejs.org/dist/v14.21.3/node-v14.21.3-linux-x64.tar.gz \
  +  | sudo tar -xz -C /usr/local --strip-components=1
   RUN make release_base

[arnoldcastro5000]

Deployed to prod on June 30, 2026. Deployment logs in slack.