link gif

CONTRIBUTING.md

@@ -6,6 +6,32 @@ Thank you for contributing! Just a few tips here:
 2. Run the test suite (e.g. `pgbench`) to make sure everything still works. The tests are in `.circleci/run_tests.sh`.
 3. Performance is important, make sure there are no regressions in your branch vs. `main`.
 
+## How to run the integration tests locally and iterate on them
+We have integration tests written in Ruby, Python, Go and Rust. 
+Below are the steps to run them in a developer-friendly way that allows iterating and quick turnaround.
+Hear me out, this should be easy, it will involve opening a shell into a container with all the necessary dependancies available for you and you can modify the test code and immediately rerun your test in the interactive shell.
+
+
+Quite simply, make sure you have docker installed and then run
+`./start_test_env.sh`
+
+That is it!
+
+Within this test environment you can modify the file in your favorite IDE and rerun the tests without having to bootstrap the entire environment again.
+
+Once the environment is ready, you can run the tests by running
+Ruby:   `cd /app/tests/ruby && bundle exec ruby <test_name>.rb --format documentation`
+Python: `cd /app && python3 tests/python/tests.py`
+Rust:   `cd /app/tests/rust && cargo run`
+Go:     `cd /app/tests/go && /usr/local/go/bin/go test`
+
+You can also rebuild PgCat directly within the environment and the tests will run against the newly built binary
+To rebuild PgCat, just run `cargo build` within the container under `/app`
+
+![Animated gif showing how to run tests](https://github.com/user-attachments/assets/2258fde3-2aed-4efb-bdc5-e4f12dcd4d33)
+
+
+
 Happy hacking!
 
 ## TODOs

start_test_env.sh

@@ -0,0 +1,34 @@
+GREEN="\033[0;32m"
+RED="\033[0;31m"
+BLUE="\033[0;34m"
+RESET="\033[0m"
+
+
+cd tests/docker/
+docker compose kill main || true
+docker compose build main
+docker compose down
+docker compose up -d
+# wait for the container to start
+while ! docker compose exec main ls; do
+    echo "Waiting for test environment to start"
+    sleep 1
+done
+echo "==================================="
+docker compose exec -e LOG_LEVEL=error -d main toxiproxy-server
+docker compose exec --workdir /app main cargo build
+docker compose exec -d --workdir /app main ./target/debug/pgcat ./.circleci/pgcat.toml
+docker compose exec --workdir /app/tests/ruby main bundle install
+docker compose exec --workdir /app/tests/python main pip3 install -r requirements.txt
+echo "Interactive test environment ready"
+echo "To run integration tests, you can use the following commands:"
+echo -e "   ${BLUE}Ruby:   ${RED}cd /app/tests/ruby && bundle exec ruby tests.rb --format documentation${RESET}"
+echo -e "   ${BLUE}Python: ${RED}cd /app && python3 tests/python/tests.py${RESET}"
+echo -e "   ${BLUE}Rust:   ${RED}cd /app/tests/rust && cargo run ${RESET}"
+echo -e "   ${BLUE}Go:     ${RED}cd /app/tests/go && /usr/local/go/bin/go test${RESET}"
+echo "the source code for tests are directly linked to the source code in the container so you can modify the code and run the tests again"
+echo "You can rebuild PgCat from within the container by running" 
+echo -e "  ${GREEN}cargo build${RESET}"
+echo "and then run the tests again"
+echo "==================================="
+docker compose exec --workdir /app/tests main bash

tests/docker/docker-compose.yml

@@ -1,4 +1,3 @@
-version: "3"
 services:
   pg1:
     image: postgres:14
@@ -48,6 +47,8 @@ services:
   main:
     build: .
     command: ["bash", "/app/tests/docker/run.sh"]
+    environment:
+      - INTERACTIVE_TEST_ENVIRONMENT=true
     volumes:
       - ../../:/app/
       - /app/target/

tests/docker/run.sh

@@ -5,6 +5,38 @@ rm /app/*.profraw || true
 rm /app/pgcat.profdata || true
 rm -rf /app/cov || true
 
+# Prepares the interactive test environment
+# 
+if [ -n "$INTERACTIVE_TEST_ENVIRONMENT" ]; then
+    ports=(5432 7432 8432 9432 10432)
+    for port in "${ports[@]}"; do
+        is_it_up=0
+        attempts=0
+        while [ $is_it_up -eq 0 ]; do
+            PGPASSWORD=postgres psql -h 127.0.0.1 -p $port -U postgres -c '\q' > /dev/null 2>&1
+            if [ $? -eq 0 ]; then
+                echo "PostgreSQL on port $port is up."
+                is_it_up=1
+            else
+                attempts=$((attempts+1))
+                if [ $attempts -gt 10 ]; then
+                    echo "PostgreSQL on port $port is down, giving up."
+                    exit 1
+                fi
+                echo "PostgreSQL on port $port is down, waiting for it to start."
+                sleep 1
+            fi
+        done
+    done
+    PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 5432  -U postgres -f /app/tests/sharding/query_routing_setup.sql
+    PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 7432  -U postgres -f /app/tests/sharding/query_routing_setup.sql
+    PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 8432  -U postgres -f /app/tests/sharding/query_routing_setup.sql
+    PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 9432  -U postgres -f /app/tests/sharding/query_routing_setup.sql
+    PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 10432 -U postgres -f /app/tests/sharding/query_routing_setup.sql
+    sleep 100000000000000000
+    exit 0
+fi
+
 export LLVM_PROFILE_FILE="/app/pgcat-%m-%p.profraw"
 export RUSTC_BOOTSTRAP=1
 export CARGO_INCREMENTAL=0