Migrate CircleCI to GitHub Actions (#162)

* Migrate CircleCI to GitHub Actions

* Add support for unit tests
* Update dependencies to match `dbt-snowflake`
* Update tox config to match `dbt-snowflake`
* Update setup.py to match `dbt-snowflake`

* Fix the "build packages" CI job

* Unlike other DBT adapters, this one contains support for three
  different flavors of MySQL, thus has a handful of duplicate files.
  Therefore W002 should be ignored, as duplicates are not an error.

* Add GitHub actions integration tests

* Used `dbt-snowflake` as an example

* Add codeowners file

* Add tests badges

* Use markdown badges instead

* Temporarily run integration tests on all PRs

* Don't use env var for adapter->version map

* Try to use " instead of '

* Try another workaround to launch the proper database service

* More temporary changes from pull_request_target to pull_request

* Attempt to set system variables for mariadb & mysql5

* Clean up database service selection

* Change pull_request back to pull_request_target

* Update changelog

* Copy Makefile test infrastructure from `dbt-snowflake` and update docs

* Fix test README link

.flake8

@@ -0,0 +1,16 @@
+[flake8]
+select =
+    E
+    W
+    F
+ignore =
+    # makes Flake8 work like black
+    W503,
+    W504,
+    # makes Flake8 work like black
+    E203,
+    E741,
+    E501,
+exclude = tests
+per-file-ignores =
+    */__init__.py: F401

.github/CODEOWNERS

@@ -0,0 +1,3 @@
+# This codeowners file is used to ensure all PRs require reviews from the appropriate users.
+
+* @dbeatty10 @mwallace582

.github/scripts/integration-test-matrix.js

@@ -0,0 +1,105 @@
+module.exports = ({ context }) => {
+  const defaultPythonVersion = "3.8";
+  const supportedPythonVersions = ["3.8", "3.9"];
+  const supportedAdapters = ["mysql", "mysql5", "mariadb"];
+  const adapterImages = {
+    mysql: "mysql:8.0",
+    mysql5: "mysql:5.7",
+    mariadb: "mariadb:10.5",
+  };
+
+  // if PR, generate matrix based on files changed and PR labels
+  if (context.eventName.includes("pull_request")) {
+    // `changes` is a list of adapter names that have related
+    // file changes in the PR
+    // ex: ['postgres', 'snowflake']
+    const changes = JSON.parse(process.env.CHANGES);
+    const labels = context.payload.pull_request.labels.map(({ name }) => name);
+    console.log("labels", labels);
+    console.log("changes", changes);
+    const testAllLabel = labels.includes("test all");
+    const include = [];
+
+    for (const adapter of supportedAdapters) {
+      if (
+        changes.includes(adapter) ||
+        testAllLabel ||
+        labels.includes(`test ${adapter}`)
+      ) {
+        for (const pythonVersion of supportedPythonVersions) {
+          if (
+            pythonVersion === defaultPythonVersion ||
+            labels.includes(`test python${pythonVersion}`) ||
+            testAllLabel
+          ) {
+            // always run tests on ubuntu by default
+            include.push({
+              os: "ubuntu-latest",
+              adapter,
+              "database-image": adapterImages[adapter],
+              "python-version": pythonVersion,
+            });
+
+            if (labels.includes("test windows") || testAllLabel) {
+              include.push({
+                os: "windows-latest",
+                adapter,
+                "database-image": adapterImages[adapter],
+                "python-version": pythonVersion,
+              });
+            }
+
+            if (labels.includes("test macos") || testAllLabel) {
+              include.push({
+                os: "macos-latest",
+                adapter,
+                "database-image": adapterImages[adapter],
+                "python-version": pythonVersion,
+              });
+            }
+          }
+        }
+      }
+    }
+
+    console.log("matrix", { include });
+
+    return {
+      include,
+    };
+  }
+  // if not PR, generate matrix of python version, adapter, and operating
+  // system to run integration tests on
+
+  const include = [];
+  // run for all adapters and python versions on ubuntu
+  for (const adapter of supportedAdapters) {
+    for (const pythonVersion of supportedPythonVersions) {
+      include.push({
+        os: 'ubuntu-latest',
+        adapter: adapter,
+        "database-image": adapterImages[adapter],
+        "python-version": pythonVersion,
+      });
+    }
+  }
+
+  // additionally include runs for all adapters, on macos and windows,
+  // but only for the default python version
+  for (const adapter of supportedAdapters) {
+    for (const operatingSystem of ["windows-latest", "macos-latest"]) {
+      include.push({
+        os: operatingSystem,
+        adapter: adapter,
+        "database-image": adapterImages[adapter],
+        "python-version": defaultPythonVersion,
+      });
+    }
+  }
+
+  console.log("matrix", { include });
+
+  return {
+    include,
+  };
+};

.github/scripts/update_dbt_core_branch.sh

@@ -0,0 +1,20 @@
+#!/bin/bash -e
+set -e
+
+git_branch=$1
+target_req_file="dev-requirements.txt"
+core_req_sed_pattern="s|dbt-core.git.*#egg=dbt-core|dbt-core.git@${git_branch}#egg=dbt-core|g"
+postgres_req_sed_pattern="s|dbt-core.git.*#egg=dbt-postgres|dbt-core.git@${git_branch}#egg=dbt-postgres|g"
+tests_req_sed_pattern="s|dbt-core.git.*#egg=dbt-tests|dbt-core.git@${git_branch}#egg=dbt-tests|g"
+if [[ "$OSTYPE" == darwin* ]]; then
+ # mac ships with a different version of sed that requires a delimiter arg
+ sed -i "" "$core_req_sed_pattern" $target_req_file
+ sed -i "" "$postgres_req_sed_pattern" $target_req_file
+ sed -i "" "$tests_req_sed_pattern" $target_req_file
+else
+ sed -i "$core_req_sed_pattern" $target_req_file
+ sed -i "$postgres_req_sed_pattern" $target_req_file
+ sed -i "$tests_req_sed_pattern" $target_req_file
+fi
+core_version=$(curl "https://raw.githubusercontent.com/dbt-labs/dbt-core/${git_branch}/core/dbt/version.py" | grep "__version__ = *"|cut -d'=' -f2)
+bumpversion --allow-dirty --new-version "$core_version" major