chore: Add appsmith user existence check for auth tests (#38069)

## Description
PR to add the check for `appsmith` user existence before any assertions
in pg-auth-test to remove the flakiness.

### 🔍 Cypress test results
<!-- This is an auto-generated comment: Cypress test results  -->
> [!WARNING]
> Tests have not run on the HEAD
0ac8736872f1d8b51b384b644dd0f3b21f725cb0 yet
> <hr>Fri, 13 Dec 2024 05:18:03 UTC
<!-- end of auto-generated comment: Cypress test results  -->


## Communication
Should the DevRel and Marketing teams inform users about this change?
- [ ] Yes
- [x] No


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **Bug Fixes**
- Enhanced testing for PostgreSQL authentication to ensure the Appsmith
user exists before access checks.

- **Tests**
- Updated existing test functions to include user existence
verification, improving the robustness of the testing process.
- Introduced new functions to verify user existence and check the
readiness of the Appsmith instance and PostgreSQL.
- Streamlined logic for readiness checks, enhancing overall testing
efficiency.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

deploy/docker/tests/pg-test-utils.sh

@@ -0,0 +1,70 @@
+#!/bin/bash
+
+# Default container name if not provided
+container_name=${container_name:-appsmith-docker-test}
+
+# Function to check if the Appsmith instance is up
+is_appsmith_instance_ready() {
+  local max_retries=200
+  local retry_count=0
+  local response_code
+
+  while [ $retry_count -lt $max_retries ]; do
+    response_code=$(curl -s -o /dev/null -w "%{http_code}" http://localhost/health)
+    if [[ $response_code -eq 200 ]]; then
+      echo "Appsmith instance is ready."
+      return 0
+    fi
+    echo "Waiting for Appsmith instance to be ready... (Attempt: $((retry_count + 1)))"
+    retry_count=$((retry_count + 1))
+    sleep 2
+  done
+  return 1
+}
+
+# Function to wait until the postgres is ready
+wait_for_postgres() {
+  local max_retries=200
+  local retry_count=0
+
+  while [ $retry_count -lt $max_retries ]; do
+    if docker exec "${container_name}" pg_isready; then
+      echo "Postgres is ready."
+      return 0
+    fi
+    echo "Waiting for Postgres to be ready... (Attempt: $((retry_count + 1)))"
+    retry_count=$((retry_count + 1))
+    sleep 2
+  done
+}
+
+# Function to check if the user exists in the database
+check_user_exists() {
+  local user
+  user=$1
+  local max_retries=200
+  local retry_count=0
+  while [ $retry_count -lt $max_retries ]; do
+    if docker exec "${container_name}" bash -c "psql -p 5432 -U postgres -c \"SELECT 1 FROM pg_roles WHERE rolname='$user';\" | grep -q 1"; then
+      echo "$user user exists."
+      return 0
+    fi
+    echo "Waiting for $user user to be created... (Attempt: $((retry_count + 1)))"
+    retry_count=$((retry_count + 1))
+    sleep 1
+  done
+  echo "$user user does not exist."
+  return 1
+}
+
+# Function to check if the Appsmith user has read access to databases
+check_user_datasource_access_with_host_port_wo_auth() {
+  docker exec "${container_name}" bash -c "psql -h 127.0.0.1 -p 5432 -U postgres -c '\l'"
+  return $?
+}
+
+# Function to check if the Appsmith user has read access to databases
+check_user_datasource_access_with_local_port_wo_auth() {
+  docker exec "${container_name}" bash -c "psql -p 5432 -U postgres -c '\l'"
+  return $?
+}

deploy/docker/tests/test-pg-auth.sh

@@ -1,8 +1,8 @@
 #!/bin/bash
 set -o errexit
-# set -x
 
 source ./composes.sh
+source ./pg-test-utils.sh
 
 
 # Function to update the APPSMITH_DB_URL in docker.env
@@ -13,41 +13,6 @@ update_db_url() {
   docker exec "${container_name}" bash -c "sed -i 's|^APPSMITH_POSTGRES_DB_URL=|APPSMITH_DB_URL=|' /appsmith-stacks/configuration/docker.env"
 }
 
-# Function to check if the Appsmith instance is up
-is_appsmith_instance_ready() {
-  local max_retries=200
-  local retry_count=0
-  local response_code
-
-  while [ $retry_count -lt $max_retries ]; do
-    response_code=$(curl -s -o /dev/null -w "%{http_code}" http://localhost/health)
-    if [[ $response_code -eq 200 ]]; then
-      echo "Appsmith instance is ready."
-      return 0
-    fi
-    echo "Waiting for Appsmith instance to be ready... (Attempt: $((retry_count + 1)))"
-    retry_count=$((retry_count + 1))
-    sleep 2
-  done
-  return 1
-}
-
-# Function to wait until the postgres is ready
-wait_for_postgres() {
-  local max_retries=200
-  local retry_count=0
-
-  while [ $retry_count -lt $max_retries ]; do
-    if docker exec "${container_name}" pg_isready; then
-      echo "Postgres is ready."
-      return 0
-    fi
-    echo "Waiting for Postgres to be ready... (Attempt: $((retry_count + 1)))"
-    retry_count=$((retry_count + 1))
-    sleep 2
-  done
-}
-
 # Function to read the password from the PostgreSQL URL in docker.env.sh
 get_appsmith_password() {
   local password
@@ -96,18 +61,6 @@ EOF
   return 1
 }
 
-# Function to check if the Appsmith user has read access to databases
-check_user_datasource_access_with_host_port_wo_auth() {
-  docker exec "${container_name}" bash -c "psql -h 127.0.0.1 -p 5432 -U postgres -c '\l'"
-  return $?
-}
-
-# Function to check if the Appsmith user has read access to databases
-check_user_datasource_access_with_local_port_wo_auth() {
-  docker exec "${container_name}" bash -c "psql -p 5432 -U postgres -c '\l'"
-  return $?
-}
-
 # Test to check if the postgres auth is enabled after upgrading from 1.50 to local image
 # Expectation:
 # 1. Appsmith instance should be able to upgrade from v1.50 to local image
@@ -167,24 +120,16 @@ test_postgres_auth_enabled_upgrade_from_150tolocal() {
     RETRYSECONDS=5
     retry_count=0
 
-    while true; do
+    # Wait until postgres to come up
-        retry_count=$((retry_count + 1))
+    wait_for_postgres
-        if docker exec "${container_name}" pg_isready &&
-          [ "$(docker exec "${container_name}" bash -c 'cat /appsmith-stacks/data/postgres/main/PG_VERSION')" = "14" ]; then
-            break
-        fi
-        if [ $retry_count -le $MAX_RETRIES ]; then
-            echo "Waiting for postgres to be up..."
-            sleep $RETRYSECONDS
-        else
-            echo "Test ${FUNCNAME[0]} Failed"
-            exit 1
-        fi
-    done
     
     # Check if the Appsmith instance is up
     if is_appsmith_instance_ready; then
-
+      if ! check_user_exists appsmith; then
+          echo "Appsmith user does not exist"
+          echo "Test ${FUNCNAME[0]} Failed ❌"
+          exit 1
+      fi
       # Check if the Appsmith user has read access to databases
       if check_user_datasource_access_with_auth; then
           echo "Test ${FUNCNAME[0]} Passed ✅"
@@ -253,12 +198,15 @@ test_postgres_auth_enabled_restart_localtolocal() {
 
     echo "Starting Appsmith local to check the auth"
     compose_appsmith_local
-
     wait_for_postgres
 
     # Check if the Appsmith instance is up
     if is_appsmith_instance_ready; then
-
+      if ! check_user_exists appsmith; then
+          echo "Appsmith user does not exist"
+          echo "Test ${FUNCNAME[0]} Failed ❌"
+          exit 1
+      fi
       # Check if the Appsmith user has read access to databases
       if check_user_datasource_access_with_auth; then
           echo "Test ${FUNCNAME[0]} Passed ✅"