From f84ebd17f9f6c07806b1523c84de7f260cf22bf4 Mon Sep 17 00:00:00 2001
From: Joshua Chen <sidachen2003@gmail.com>
Date: Sun, 24 Nov 2024 17:24:29 -0500
Subject: [PATCH] experiment generating multiple login users for pgbouncer

---
 db/docker-compose.yml           | 13 +++++++++++--
 db/pgbouncer/Dockerfile         |  6 ++++++
 db/pgbouncer/generate-config.sh | 22 ++++++++++++++++++++++
 3 files changed, 39 insertions(+), 2 deletions(-)
 create mode 100644 db/pgbouncer/Dockerfile
 create mode 100755 db/pgbouncer/generate-config.sh

diff --git a/db/docker-compose.yml b/db/docker-compose.yml
index 93ab291..c1b1444 100644
--- a/db/docker-compose.yml
+++ b/db/docker-compose.yml
@@ -37,11 +37,20 @@ services:
       - traefik
 
   pgbouncer:
-    image: edoburu/pgbouncer:latest
+    build:
+      context: ./pgbouncer
     container_name: ${DB_BOUNCER?DB_BOUNCER}
     restart: always
     environment:
-      DATABASE_URL: postgresql://${HASURA_DB_USER?HASURA_DB_USER}:${HASURA_DB_PASSWORD?HASURA_DB_PASSWORD}@${DB_HOST?DB_HOST}:${DB_PORT?DB_PORT}/${FERRY_DB_NAME?FERRY_DB_NAME}
+      DB_USER: ${DB_USER?DB_USER}
+      DB_ROOT_PASSWORD: ${DB_ROOT_PASSWORD?DB_ROOT_PASSWORD}
+      FERRY_DB_USER: ${FERRY_DB_USER?FERRY_DB_USER}
+      FERRY_DB_PASSWORD: ${FERRY_DB_PASSWORD?FERRY_DB_PASSWORD}
+      HASURA_DB_USER: ${HASURA_DB_USER?HASURA_DB_USER}
+      HASURA_DB_PASSWORD: ${HASURA_DB_PASSWORD?HASURA_DB_PASSWORD}
+      DB_NAME: ${FERRY_DB_NAME?FERRY_DB_NAME}
+      DB_HOST: ${DB_HOST?DB_HOST}
+      DB_PORT: ${DB_PORT?DB_PORT}
       AUTH_TYPE: scram-sha-256
       QUERY_WAIT_TIMEOUT: 600
       MAX_CLIENT_CONN: 5000
diff --git a/db/pgbouncer/Dockerfile b/db/pgbouncer/Dockerfile
new file mode 100644
index 0000000..5666ce2
--- /dev/null
+++ b/db/pgbouncer/Dockerfile
@@ -0,0 +1,6 @@
+FROM edoburu/pgbouncer:latest
+
+# Custom step to generate all users from environment variables
+COPY generate-config.sh /
+# Run our script and then the default entrypoint
+ENTRYPOINT ["/bin/sh", "-c", "/generate-config.sh && /entrypoint.sh /usr/bin/pgbouncer /etc/pgbouncer/pgbouncer.ini"]
diff --git a/db/pgbouncer/generate-config.sh b/db/pgbouncer/generate-config.sh
new file mode 100755
index 0000000..35109f1
--- /dev/null
+++ b/db/pgbouncer/generate-config.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+
+set -e
+
+output_file="/etc/pgbouncer/userlist.txt"
+
+> "$output_file"
+
+# See https://github.com/edoburu/docker-pgbouncer/blob/master/examples/generate-userlist;
+# The MD5 should be formed from password+username
+compute_md5() {
+  password="$1"
+  username="$2"
+  printf "md5%s" "$(printf "%s%s" "$password" "$username" | md5sum | awk '{print $1}')"
+}
+
+echo "\"$DB_USER\" \"$(compute_md5 "$DB_ROOT_PASSWORD" "$DB_USER")\"" >> "$output_file"
+echo "\"$FERRY_DB_USER\" \"$(compute_md5 "$FERRY_DB_PASSWORD" "$FERRY_DB_USER")\"" >> "$output_file"
+echo "\"$HASURA_DB_USER\" \"$(compute_md5 "$HASURA_DB_PASSWORD" "$HASURA_DB_USER")\"" >> "$output_file"
+
+echo "Userlist generated in $output_file"
+cat "$output_file"