Add GitHub Actions CI (#181)

* Add GitHub Actions CI

Adds GitHub Actions for:

- build & test for all combinations of Elixir 1.10, 1.11, 1.12, 1.13, 1.14, and 1.15, plus OTP 22, 23, 24, 25, and 26
- basic code quality checks (and a formatting fix and unused dependency removal to match)
- checking for retired Hex dependencies

Also updates the maintainers list and URL to reflect the new Felt org.

* Run mix format

* Fix build & test action

* Test a failure case discovered by the test matrix

.github/actions/elixir-setup/action.yml

@@ -0,0 +1,141 @@
+name: Setup Elixir Project
+description: Checks out the code, configures Elixir, fetches dependencies, and manages build caching.
+inputs:
+  elixir-version:
+    required: true
+    type: string
+    description: Elixir version to set up
+  otp-version:
+    required: true
+    type: string
+    description: OTP version to set up
+  #################################################################
+  # Everything below this line is optional.
+  #
+  # It's designed to make compiling a reasonably standard Elixir
+  # codebase "just work," though there may be speed gains to be had
+  # by tweaking these flags.
+  #################################################################
+  build-deps:
+    required: false
+    type: boolean
+    default: true
+    description: True if we should compile dependencies
+  build-app:
+    required: false
+    type: boolean
+    default: true
+    description: True if we should compile the application itself
+  build-flags:
+    required: false
+    type: string
+    default: '--all-warnings'
+    description: Flags to pass to mix compile
+  install-rebar:
+    required: false
+    type: boolean
+    default: true
+    description: By default, we will install Rebar (mix local.rebar --force).
+  install-hex:
+    required: false
+    type: boolean
+    default: true
+    description: By default, we will install Hex (mix local.hex --force).
+  cache-key:
+    required: false
+    type: string
+    default: 'v1'
+    description: If you need to reset the cache for some reason, you can change this key.
+outputs:
+  otp-version:
+    description: "Exact OTP version selected by the BEAM setup step"
+    value: ${{ steps.beam.outputs.otp-version }}
+  elixir-version:
+    description: "Exact Elixir version selected by the BEAM setup step"
+    value: ${{ steps.beam.outputs.elixir-version }}
+runs:
+  using: "composite"
+  steps:
+    - name: Setup elixir
+      uses: erlef/setup-beam@v1.15.4
+      id: beam
+      with:
+        elixir-version: ${{ inputs.elixir-version }}
+        otp-version: ${{ inputs.otp-version }}
+
+    - name: Get deps cache
+      uses: actions/cache@v2
+      with:
+        path: deps/
+        key: deps-${{ inputs.cache-key }}-${{ runner.os }}-${{ hashFiles('**/mix.lock') }}
+        restore-keys: |
+          deps-${{ inputs.cache-key }}-${{ runner.os }}-
+
+    - name: Get build cache
+      uses: actions/cache@v2
+      id: build-cache
+      with:
+        path: _build/${{env.MIX_ENV}}/
+        key: build-${{ inputs.cache-key }}-${{ runner.os }}-${{ inputs.otp-version }}-${{ inputs.elixir-version }}-${{ env.MIX_ENV }}-${{ hashFiles('**/mix.lock') }}
+        restore-keys: |
+          build-${{ inputs.cache-key }}-${{ runner.os }}-${{ inputs.otp-version }}-${{ inputs.elixir-version }}-${{ env.MIX_ENV }}-
+
+    - name: Get Hex cache
+      uses: actions/cache@v2
+      id: hex-cache
+      with:
+        path: ~/.hex
+        key: hex-${{ inputs.cache-key }}-${{ runner.os }}-${{ inputs.otp-version }}-${{ inputs.elixir-version }}-${{ hashFiles('**/mix.lock') }}
+        restore-keys: |
+          hex-${{ inputs.cache-key }}-${{ runner.os }}-${{ inputs.otp-version }}-${{ inputs.elixir-version }}-
+
+    - name: Get Mix cache
+      uses: actions/cache@v2
+      id: mix-cache
+      with:
+        path: ${{ env.MIX_HOME || '~/.mix' }}
+        key: mix-${{ inputs.cache-key }}-${{ runner.os }}-${{ inputs.otp-version }}-${{ inputs.elixir-version }}-${{ hashFiles('**/mix.lock') }}
+        restore-keys: |
+          mix-${{ inputs.cache-key }}-${{ runner.os }}-${{ inputs.otp-version }}-${{ inputs.elixir-version }}-
+
+    # In my experience, I have issues with incremental builds maybe 1 in 100
+    # times that are fixed by doing a full recompile.
+    # In order to not waste dev time on such trivial issues (while also reaping
+    # the time savings of incremental builds for *most* day-to-day development),
+    # I force a full recompile only on builds that we retry.
+    - name: Clean to rule out incremental build as a source of flakiness
+      if: github.run_attempt != '1'
+      run: | 
+        mix deps.clean --all
+        mix clean
+      shell: sh
+
+    - name: Install Rebar
+      run: mix local.rebar --force --if-missing
+      shell: sh
+      if: inputs.install-rebar == 'true'
+
+    - name: Install Hex
+      run: mix local.hex --force --if-missing
+      shell: sh
+      if: inputs.install-hex == 'true'
+
+    - name: Install Dependencies
+      run: mix deps.get
+      shell: sh
+
+    # Normally we'd use `mix deps.compile` here, however that incurs a large
+    # performance penalty when the dependencies are already fully compiled:
+    # https://elixirforum.com/t/github-action-cache-elixir-always-recompiles-dependencies-elixir-1-13-3/45994/12
+    #
+    # Accoring to Jose Valim at the above link `mix loadpaths` will check and
+    # compile missing dependencies
+    - name: Compile Dependencies
+      run: mix loadpaths
+      shell: sh
+      if: inputs.build-deps == 'true'
+
+    - name: Compile Application
+      run: mix compile ${{ inputs.build-flags }}
+      shell: sh
+      if: inputs.build-app == 'true'

.github/dependabot.yml

@@ -0,0 +1,10 @@
+version: 2
+updates:
+- package-ecosystem: mix
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "11:00"
+  open-pull-requests-limit: 10
+  assignees:
+  - s3cur3

.github/workflows/elixir-build-and-test.yml

@@ -0,0 +1,77 @@
+name: Elixir Unit Tests
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - "**"
+
+jobs:
+  build:
+    name: Elixir Unit Tests
+    runs-on: ubuntu-20.04
+    env:
+      MIX_ENV: test
+    strategy:
+      matrix:
+        elixir: ["1.10.4", "1.11.4", "1.12.3", "1.13.4", "1.14.4", "1.15.5"]
+        otp: ["22.3", "23.3.4", "24.3.4", "25.3.2", "26.0.2"]
+        exclude:
+          # Elixir 1.10 only supports up to OTP 23
+          - elixir: "1.10.4"
+            otp: "26.0.2"
+          - elixir: "1.10.4"
+            otp: "25.3.2"
+          - elixir: "1.10.4"
+            otp: "24.3.4"
+          # Elixir 1.11 doesn't support the latest OTP
+          - elixir: "1.11.4"
+            otp: "25.3.2"
+          - elixir: "1.11.4"
+            otp: "26.0.2"
+          # Elixir 1.12 doesn't support the latest OTP
+          - elixir: "1.12.3"
+            otp: "25.3.2"
+          - elixir: "1.12.3"
+            otp: "26.0.2"
+          # Elixir 1.13 doesn't support the latest OTP
+          - elixir: "1.13.4"
+            otp: "26.0.2"
+          # Elixir 1.14 requires at least OTP 23
+          - elixir: "1.14.4"
+            otp: "22.3"
+          # Elixir 1.15 requires at least OTP 24
+          - elixir: "1.15.5"
+            otp: "22.3"
+          - elixir: "1.15.5"
+            otp: "23.3.4"
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Setup Elixir Project
+        uses: ./.github/actions/elixir-setup
+        with:
+          elixir-version: ${{ matrix.elixir }}
+          otp-version: ${{ matrix.otp }}
+          build-app: false
+
+      - name: Compile with warnings as errors
+        if: ${{ matrix.elixir != '1.11.4' && matrix.elixir != '1.10.4' }} 
+        run: mix compile --warnings-as-errors
+
+        # stream_data config doesn't work on Elixir 1.10, but we can at least compile
+      - name: Compile
+        if: ${{ matrix.elixir == '1.10.4' }} 
+        run: mix compile
+
+      - name: Run tests with warnings as errors
+        if: ${{ matrix.elixir != '1.11.4' && matrix.elixir != '1.10.4' }} 
+        run: mix test --warnings-as-errors
+
+      - name: Run tests
+        if: ${{ matrix.elixir == '1.11.4' }}
+        run: mix test

.github/workflows/elixir-quality-checks.yml

@@ -0,0 +1,45 @@
+name: Elixir Quality Checks
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - "**"
+
+jobs:
+  quality_checks:
+    name: Elixir Quality Checks
+    runs-on: ubuntu-latest
+    env:
+      # In MIX_ENV=test, `$ mix xref graph` shows us a whole bunch of
+      # test stuff that isn't really relevant.
+      # The other checks don't really care what environment they run in.
+      MIX_ENV: dev
+      elixir: "1.15.4"
+      otp: "26.0.2"
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Setup Elixir Project
+        uses: ./.github/actions/elixir-setup
+        with:
+          elixir-version: ${{ env.elixir }}
+          otp-version: ${{ env.otp }}
+          build-app: false
+
+      - name: Check for unused deps
+        run: mix deps.unlock --check-unused
+
+      - name: Check code formatting
+        run: mix format --check-formatted
+        # We run all checks here even if others failed so that
+        # we give devs as much feedback as possible & save some time.
+        if: always()
+
+      - name: Check for compile-time dependencies between modules
+        run: mix xref graph --label compile-connected --fail-above 0
+        if: always()

.github/workflows/elixir-retired-packages-check.yml

@@ -0,0 +1,32 @@
+name: Elixir Retired Packages Check
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - "**"
+
+jobs:
+  retired_packages:
+    name: Elixir Retired Packages Check
+    runs-on: ubuntu-latest
+    env:
+      MIX_ENV: dev
+      elixir: "1.15.4"
+      otp: "26.0.2"
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Setup Elixir Project
+        uses: ./.github/actions/elixir-setup
+        with:
+          elixir-version: ${{ env.elixir }}
+          otp-version: ${{ env.otp }}
+          build-app: false
+
+      - name: Check for retired/abandoned deps
+        run: mix hex.audit

lib/geo/geometry_collection.ex

@@ -3,6 +3,10 @@ defmodule Geo.GeometryCollection do
   Defines the GeometryCollection struct.
   """
 
-  @type t :: %Geo.GeometryCollection{geometries: [Geo.geometry()], srid: integer | nil, properties: map}
+  @type t :: %Geo.GeometryCollection{
+          geometries: [Geo.geometry()],
+          srid: integer | nil,
+          properties: map
+        }
   defstruct geometries: [], srid: nil, properties: %{}
 end

lib/geo/line_string.ex

@@ -3,6 +3,10 @@ defmodule Geo.LineString do
   Defines the LineString struct.
   """
 
-  @type t :: %Geo.LineString{coordinates: [{number, number}], srid: integer | nil, properties: map}
+  @type t :: %Geo.LineString{
+          coordinates: [{number, number}],
+          srid: integer | nil,
+          properties: map
+        }
   defstruct coordinates: [], srid: nil, properties: %{}
 end

lib/geo/line_stringz.ex

@@ -3,6 +3,10 @@ defmodule Geo.LineStringZ do
   Defines the LineStringZ struct.
   """
 
-  @type t :: %__MODULE__{coordinates: [{number, number, number}], srid: integer | nil, properties: map}
+  @type t :: %__MODULE__{
+          coordinates: [{number, number, number}],
+          srid: integer | nil,
+          properties: map
+        }
   defstruct coordinates: [], srid: nil, properties: %{}
 end

lib/geo/multi_point.ex

@@ -3,6 +3,10 @@ defmodule Geo.MultiPoint do
   Defines the MultiPoint struct.
   """
 
-  @type t :: %Geo.MultiPoint{coordinates: [{number, number}], srid: integer | nil, properties: map}
+  @type t :: %Geo.MultiPoint{
+          coordinates: [{number, number}],
+          srid: integer | nil,
+          properties: map
+        }
   defstruct coordinates: [], srid: nil, properties: %{}
 end

lib/geo/multi_pointz.ex

@@ -3,6 +3,10 @@ defmodule Geo.MultiPointZ do
   Defines the MultiPointZ struct.
   """
 
-  @type t :: %__MODULE__{coordinates: [{number, number, number}], srid: integer | nil, properties: map}
+  @type t :: %__MODULE__{
+          coordinates: [{number, number, number}],
+          srid: integer | nil,
+          properties: map
+        }
   defstruct coordinates: [], srid: nil, properties: %{}
 end

lib/geo/pointm.ex

@@ -3,6 +3,10 @@ defmodule Geo.PointM do
   Defines the PointM struct.
   """
 
-  @type t :: %Geo.PointM{coordinates: {number, number, number}, srid: integer | nil, properties: map}
+  @type t :: %Geo.PointM{
+          coordinates: {number, number, number},
+          srid: integer | nil,
+          properties: map
+        }
   defstruct coordinates: {0, 0, 0}, srid: nil, properties: %{}
 end

lib/geo/pointz.ex

@@ -3,6 +3,10 @@ defmodule Geo.PointZ do
   Defines the PointZ struct.
   """
 
-  @type t :: %Geo.PointZ{coordinates: {number, number, number}, srid: integer | nil, properties: map}
+  @type t :: %Geo.PointZ{
+          coordinates: {number, number, number},
+          srid: integer | nil,
+          properties: map
+        }
   defstruct coordinates: {0, 0, 0}, srid: nil, properties: %{}
 end