[FABG-924] Simplify upstream patching

Signed-off-by: Aleksandar Likic <[email protected]>

Makefile

@@ -563,8 +563,11 @@ endif
 .PHONY: thirdparty-pin
 thirdparty-pin:
 	@echo "Pinning third party packages ..."
-	@UPSTREAM_COMMIT=$(THIRDPARTY_FABRIC_COMMIT) UPSTREAM_BRANCH=$(THIRDPARTY_FABRIC_BRANCH) scripts/third_party_pins/fabric/apply_upstream.sh
-	@UPSTREAM_COMMIT=$(THIRDPARTY_FABRIC_CA_COMMIT) UPSTREAM_BRANCH=$(THIRDPARTY_FABRIC_CA_BRANCH) scripts/third_party_pins/fabric-ca/apply_upstream.sh
+	@THIRDPARTY_FABRIC_COMMIT=$(THIRDPARTY_FABRIC_COMMIT) \
+	THIRDPARTY_FABRIC_BRANCH=$(THIRDPARTY_FABRIC_BRANCH) \
+	THIRDPARTY_FABRIC_CA_COMMIT=$(THIRDPARTY_FABRIC_CA_COMMIT) \
+	THIRDPARTY_FABRIC_CA_BRANCH=$(THIRDPARTY_FABRIC_CA_BRANCH) \
+	scripts/third_party_pins/apply_thirdparty_pins.sh
 
 .PHONY: populate
 populate: populate-vendor populate-fixtures-stable

scripts/third_party_pins/README.md

@@ -0,0 +1,40 @@
+Fabric-sdk-go reuses fabric and fabric-ca code by first copying
+desired files from upstream repos and then patching them to work
+locally. The process of patching is a simple git merge which
+replays changes from the last successful patch. For this to work,
+the two steps (pulling files from upstream and patching) must
+always be maintained in their own separate commits each time we
+pull in the new upstream version.
+
+Note that replaying changes from old commits using a simple
+'git am' doesn't work well because a git patch created with
+'git format-patch' doesn't have a knowledge of the common
+ancestor of the master and the commit we want to replay,
+so we end up with many unexpected conflicts.
+
+Here are full steps for pulling code from upstream and patching:
+```
+> make thirdparty-pin
+```
+We must now commit upstream files first. This will keep the
+subsequent patch in its own clean commit so we can use it in the
+future.
+```
+> git add .
+> git commit --signoff -m "Apply upstream"
+```
+Now we need to replay changes from the last correct patch.
+We do it using git, with the help of a temporary branch where we
+first copy the changes we want to replay. This example assumes
+that the last correct patch was committed as ```5678```, and its
+parent is the commit ```1234```.
+```
+> git format-patch --stdout 1234..5678 > ~/last.patch
+> git checkout -b fix 1234
+> git am ~/last.patch
+> git checkout master
+> git merge fix
+```
+If necessary, fix any conflicts and commit
+
+Amend as required, and push all commits.

scripts/third_party_pins/apply_thirdparty_pins.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+#
+# Copyright SecureKey Technologies Inc. All Rights Reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# This script fetches code originating from other upstream projects
+# These files are checked into internal paths.
+
+set -e
+
+if output=$(git status --porcelain) && [ -z "$output" ]
+then
+  echo "Working directory clean, proceeding with upstream patching"
+else
+  echo "ERROR: git status must be clean before applying upstream patches"
+  exit 1
+fi
+
+export UPSTREAM_COMMIT="${THIRDPARTY_FABRIC_COMMIT}"
+export UPSTREAM_BRANCH="${THIRDPARTY_FABRIC_BRANCH}"
+scripts/third_party_pins/fabric/apply_upstream.sh
+
+export UPSTREAM_COMMIT="${THIRDPARTY_FABRIC_CA_COMMIT}"
+export UPSTREAM_BRANCH="${THIRDPARTY_FABRIC_CA_BRANCH}"
+scripts/third_party_pins/fabric-ca/apply_upstream.sh

scripts/third_party_pins/common/apply_header_notice.sh

@@ -7,7 +7,7 @@
 
 set -e
 
-FILES=($FILES)
+FILE=$1
 NOTICE=$'Notice: This file has been modified for Hyperledger Fabric SDK Go usage.\nPlease review third_party pinning scripts and patches for more details.'
 SPDX_LICENSE_ID="SPDX-License-Identifier: Apache-2.0"
 OLD_APACHE_LICENSE_ID="http://www.apache.org/licenses/LICENSE-2.0"
@@ -18,16 +18,13 @@ if [ -z $WORKING_DIR ]; then
     WORKING_DIR=`pwd`
 fi
 
-for i in "${FILES[@]}"
-do
-    if APPLIED=`scripts/third_party_pins/common/insert_header_notice.sh ${WORKING_DIR}/${i} "$NOTICE" "$SPDX_LICENSE_ID"`; then
-        echo "$APPLIED" > ${WORKING_DIR}/${i}
-    elif APPLIED=`scripts/third_party_pins/common/insert_header_notice.sh ${WORKING_DIR}/${i} "$NOTICE" "$OLD_APACHE_LICENSE_ID"`; then
-        echo "$APPLIED" > ${WORKING_DIR}/${i}
-    elif [ "$ALLOW_NONE_LICENSE_ID" == "true" ] && APPLIED=`scripts/third_party_pins/common/insert_header_notice.sh ${WORKING_DIR}/${i} "$NOTICE" "$NONE_LICENSE_ID"`; then
-        echo "$APPLIED" > ${WORKING_DIR}/${i}
-    else
-        echo "Failed to apply notice to ${WORKING_DIR}/${i}"
-        exit 1    
-    fi
-done
+if APPLIED=`scripts/third_party_pins/common/insert_header_notice.sh ${WORKING_DIR}/${FILE} "$NOTICE" "$SPDX_LICENSE_ID"`; then
+    echo "$APPLIED" > ${WORKING_DIR}/${FILE}
+elif APPLIED=`scripts/third_party_pins/common/insert_header_notice.sh ${WORKING_DIR}/${FILE} "$NOTICE" "$OLD_APACHE_LICENSE_ID"`; then
+    echo "$APPLIED" > ${WORKING_DIR}/${FILE}
+elif [ "$ALLOW_NONE_LICENSE_ID" == "true" ] && APPLIED=`scripts/third_party_pins/common/insert_header_notice.sh ${WORKING_DIR}/${FILE} "$NOTICE" "$NONE_LICENSE_ID"`; then
+    echo "$APPLIED" > ${WORKING_DIR}/${FILE}
+else
+    echo "Failed to apply notice to ${WORKING_DIR}/${FILE}"
+    exit 1
+fi