inits hermit; installs python3.9 (#11)

* inits hermit; installs python3.9

* add developer instructions

README.md

@@ -75,4 +75,14 @@ gcloud auth login --update-adc
 ```
 No additional configuration is required in your application's code to use this token.
 
-However, for authenticating to Databricks and AWS you will need to provide a token and secret key respectively. These can be passed directly to the `DatabricksResource` object or set as environment variables. The following example shows how to provide these values in the configuration file.
+However, for authenticating to Databricks and AWS you will need to provide a token and secret key respectively. These can be passed directly to the `DatabricksResource` object or set as environment variables. The following example shows how to provide these values in the configuration file.
+
+## For Developers
+
+### Using hermit for managing Python
+When developing cascade, you can optionally use [hermit](https://cashapp.github.io/hermit/usage/get-started/) to manage the Python executable used by cascade. Together with using poetry to manage dependencies, this will ensure that your development environment is identical to other contributors. Follow the linked instructions for installing hermit and then you can create a virtualenv with [email protected] by running:
+
+`. ./bin/activate-hermit`
+
+Then, install the dependencies with poetry:
+`poetry install`

bin/.python3@3.9.pkg

@@ -0,0 +1 @@
+hermit

bin/README.hermit.md

@@ -0,0 +1,7 @@
+# Hermit environment
+
+This is a [Hermit](https://github.com/cashapp/hermit) bin directory.
+
+The symlinks in this directory are managed by Hermit and will automatically
+download and install Hermit itself as well as packages. These packages are
+local to this environment.

bin/activate-hermit

@@ -0,0 +1,21 @@
+#!/bin/bash
+# This file must be used with "source bin/activate-hermit" from bash or zsh.
+# You cannot run it directly
+#
+# THIS FILE IS GENERATED; DO NOT MODIFY
+
+if [ "${BASH_SOURCE-}" = "$0" ]; then
+  echo "You must source this script: \$ source $0" >&2
+  exit 33
+fi
+
+BIN_DIR="$(dirname "${BASH_SOURCE[0]:-${(%):-%x}}")"
+if "${BIN_DIR}/hermit" noop > /dev/null; then
+  eval "$("${BIN_DIR}/hermit" activate "${BIN_DIR}/..")"
+
+  if [ -n "${BASH-}" ] || [ -n "${ZSH_VERSION-}" ]; then
+      hash -r 2>/dev/null
+    fi
+
+    echo "Hermit environment $("${HERMIT_ENV}"/bin/hermit env HERMIT_ENV) activated"
+fi

bin/hermit

@@ -0,0 +1,43 @@
+#!/bin/bash
+#
+# THIS FILE IS GENERATED; DO NOT MODIFY
+
+set -eo pipefail
+
+export HERMIT_USER_HOME=~
+
+if [ -z "${HERMIT_STATE_DIR}" ]; then
+  case "$(uname -s)" in
+  Darwin)
+    export HERMIT_STATE_DIR="${HERMIT_USER_HOME}/Library/Caches/hermit"
+    ;;
+  Linux)
+    export HERMIT_STATE_DIR="${XDG_CACHE_HOME:-${HERMIT_USER_HOME}/.cache}/hermit"
+    ;;
+  esac
+fi
+
+export HERMIT_DIST_URL="${HERMIT_DIST_URL:-https://github.com/cashapp/hermit/releases/download/stable}"
+HERMIT_CHANNEL="$(basename "${HERMIT_DIST_URL}")"
+export HERMIT_CHANNEL
+export HERMIT_EXE=${HERMIT_EXE:-${HERMIT_STATE_DIR}/pkg/hermit@${HERMIT_CHANNEL}/hermit}
+
+if [ ! -x "${HERMIT_EXE}" ]; then
+  echo "Bootstrapping ${HERMIT_EXE} from ${HERMIT_DIST_URL}" 1>&2
+  INSTALL_SCRIPT="$(mktemp)"
+  # This value must match that of the install script
+  INSTALL_SCRIPT_SHA256="180e997dd837f839a3072a5e2f558619b6d12555cd5452d3ab19d87720704e38"
+  if [ "${INSTALL_SCRIPT_SHA256}" = "BYPASS" ]; then
+    curl -fsSL "${HERMIT_DIST_URL}/install.sh" -o "${INSTALL_SCRIPT}"
+  else
+    # Install script is versioned by its sha256sum value
+    curl -fsSL "${HERMIT_DIST_URL}/install-${INSTALL_SCRIPT_SHA256}.sh" -o "${INSTALL_SCRIPT}"
+    # Verify install script's sha256sum
+    openssl dgst -sha256 "${INSTALL_SCRIPT}" | \
+      awk -v EXPECTED="$INSTALL_SCRIPT_SHA256" \
+      '$2!=EXPECTED {print "Install script sha256 " $2 " does not match " EXPECTED; exit 1}'
+  fi
+  /bin/bash "${INSTALL_SCRIPT}" 1>&2
+fi
+
+exec "${HERMIT_EXE}" --level=fatal exec "$0" -- "$@"

bin/pip

@@ -0,0 +1 @@
+[email protected]

bin/pip3

@@ -0,0 +1 @@
+[email protected]

bin/pip3.9

@@ -0,0 +1 @@
+.[email protected]

bin/pydoc3

@@ -0,0 +1 @@
+[email protected]

bin/pydoc3.9

@@ -0,0 +1 @@
+.[email protected]

bin/python

@@ -0,0 +1 @@
+[email protected]

bin/python3

@@ -0,0 +1 @@
+[email protected]

bin/python3-config

@@ -0,0 +1 @@
+[email protected]

bin/python3.9

@@ -0,0 +1 @@
+.[email protected]

bin/python3.9-config

@@ -0,0 +1 @@
+[email protected]