Enable generation and comparison of public API snapshots

Makefile

@@ -152,6 +152,7 @@ install-tools:
 	cd $(TOOLS_MOD_DIR) && go install github.com/ory/go-acc
 	cd $(TOOLS_MOD_DIR) && go install github.com/pavius/impi/cmd/impi
 	cd $(TOOLS_MOD_DIR) && go install github.com/tcnksm/ghr
+	cd $(TOOLS_MOD_DIR) && go install golang.org/x/exp/cmd/apidiff
 	cd $(TOOLS_MOD_DIR) && go install golang.org/x/tools/cmd/goimports
 	cd cmd/mdatagen && go install ./
 	cd cmd/checkdoc && go install ./
@@ -372,3 +373,13 @@ certs-dryrun:
 .PHONY: checkdoc
 checkdoc:
 	go run cmd/checkdoc/main.go cmd/checkdoc/docs.go --project-path $(CURDIR) --component-rel-path $(COMP_REL_PATH) --module-name $(MOD_NAME)
+
+# Construct new API state snapshots
+.PHONY: apidiff-build
+apidiff-build:
+	@$(foreach pkg,$(ALL_PKGS),$(call exec-command,./internal/buildscripts/gen-apidiff.sh -p $(pkg)))
+
+# Compare API state snapshots
+.PHONY: apidiff-compare
+apidiff-compare:
+	@$(foreach pkg,$(ALL_PKGS),$(call exec-command,./internal/buildscripts/compare-apidiff.sh -p $(pkg)))

internal/buildscripts/compare-apidiff.sh

@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+
+# This script is used to compare API state snapshots to the current package state in order to validate releases are not breaking backwards compatibility.
+
+usage() {
+  echo "Usage: $0"
+  echo
+  echo "-p  Package to generate API state snapshot of. Default: ''"
+  echo "-d  directory where prior states will be read from. Default: './internal/data/apidiff'"
+  exit 1
+}
+
+package=""
+input_dir="./internal/data/apidiff"
+
+
+while getopts "p:d:" o; do
+    case "${o}" in
+        p)
+            package=$OPTARG
+            ;;
+        d)
+            input_dir=$OPTARG
+            ;;
+        *)
+            usage
+            ;;
+    esac
+done
+shift $((OPTIND-1))
+
+if [ -z $package ]; then
+  usage
+fi
+
+set -e
+
+if [ -d $input_dir/$package ]; then
+  changes=$(apidiff $input_dir/$package/apidiff.state $package)
+  if [ ! -z "$changes" -a "$changes"!=" " ]; then
+    echo "Changes found in $package:"
+    echo "$changes"
+  fi
+fi

internal/buildscripts/gen-apidiff.sh

@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+
+# This script is used to create API state snapshots used to validate releases are not breaking backwards compatibility.
+
+usage() {
+  echo "Usage: $0"
+  echo
+  echo "-d  Dry-run mode. No project files will not be modified. Default: 'false'"
+  echo "-p  Package to generate API state snapshot of. Default: ''"
+  echo "-o  Output directory where state will be written to. Default: './internal/data/apidiff'"
+  exit 1
+}
+
+dry_run=false
+package=""
+output_dir="./internal/data/apidiff"
+
+
+while getopts "dp:o:" o; do
+    case "${o}" in
+        d)
+            dry_run=true
+            ;;
+        p)
+            package=$OPTARG
+            ;;
+        o)
+            output_dir=$OPTARG
+            ;;
+        *)
+            usage
+            ;;
+    esac
+done
+shift $((OPTIND-1))
+
+if [ -z $package ]; then
+  usage
+fi
+
+set -ex
+
+# Create temp dir for generated files.
+tmp_dir=$(mktemp -d -t apidiff)
+clean_up() {
+    ARG=$?
+    if [ $dry_run = true ]; then
+      echo "Dry-run complete. Generated files can be found in $tmp_dir"
+    else
+      rm -rf "$tmp_dir"
+    fi
+    exit $ARG
+}
+trap clean_up EXIT
+
+mkdir -p $tmp_dir/$package
+
+apidiff -w $tmp_dir/$package/apidiff.state $package
+
+# Copy files if not in dry-run mode.
+if [ $dry_run = false ]; then
+  mkdir -p "$output_dir/$package" && \
+  cp "$tmp_dir/$package/apidiff.state" \
+     "$output_dir/$package"
+fi

internal/tools/go.mod

@@ -11,5 +11,6 @@ require (
 	github.com/ory/go-acc v0.2.6
 	github.com/pavius/impi v0.0.3
 	github.com/tcnksm/ghr v0.13.0
+	golang.org/x/exp v0.0.0-20200331195152-e8c3332aa8e5
 	golang.org/x/tools v0.1.0
 )

internal/tools/go.sum

@@ -721,6 +721,7 @@ golang.org/x/exp v0.0.0-20191227195350-da58074b4299/go.mod h1:2RIsYlXP63K8oxa1u0
 golang.org/x/exp v0.0.0-20200119233911-0405dc783f0a/go.mod h1:2RIsYlXP63K8oxa1u096TMicItID8zy7Y6sNkU49FU4=
 golang.org/x/exp v0.0.0-20200207192155-f17229e696bd/go.mod h1:J/WKrq2StrnmMY6+EHIKF9dgMWnmCNThgcyBT1FY9mM=
 golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6/go.mod h1:3jZMyOhIsHpP37uCMkUooju7aAi5cS1Q23tOzKc+0MU=
+golang.org/x/exp v0.0.0-20200331195152-e8c3332aa8e5 h1:FR+oGxGfbQu1d+jglI3rCkjAjUnhRSZcUxr+DqlDLNo=
 golang.org/x/exp v0.0.0-20200331195152-e8c3332aa8e5/go.mod h1:4M0jN8W1tt0AVLNr8HDosyJCDCDuyL9N9+3m7wDWgKw=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
 golang.org/x/image v0.0.0-20190802002840-cff245a6509b/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=

internal/tools/tools.go

@@ -30,5 +30,6 @@ import (
 	_ "github.com/ory/go-acc"
 	_ "github.com/pavius/impi/cmd/impi"
 	_ "github.com/tcnksm/ghr"
+	_ "golang.org/x/exp/cmd/apidiff"
 	_ "golang.org/x/tools/cmd/goimports"
 )