refactor: better HTTP POST error handling

backport.sh

@@ -2,11 +2,29 @@
 set -e
 set -o pipefail
 
+http_post() {
+  local url=$1
+  local json=$2
+
+  if ! result=$(curl -XPOST -fsL \
+    --output /dev/null \
+    -w '{"http_code":%{http_code},"url_effective":"%{url_effective}"}' \
+    -H 'Accept: application/vnd.github.v3+json' \
+    -H "Authorization: Bearer ${INPUT_TOKEN}" \
+    -H "Content-Type: application/json" \
+    -d "${json}" \
+    "${url}"); then
+    local message
+    message=$(echo "${result}"| jq -r -s 'add | (.http_code|tostring) + ": " + .message + " effective url: " + .url_effective')
+    echo "::error::Error in HTTP POST to ${url} of \`${json}\`: ${message}"
+  fi
+}
+
 fail() {
   local message=$1
   local error=$2
 
-  echo "::error::${message}"
+  echo "::error::${message} (${error})"
 
   local comment="${message}"
   if [ -n "${error}" ]
@@ -19,13 +37,7 @@ fail() {
   local comments_url
   comments_url=$(jq --raw-output .pull_request._links.comments.href "${GITHUB_EVENT_PATH}")
 
-  curl -XPOST -fsSL \
-    --output /dev/null \
-    -H 'Accept: application/vnd.github.v3+json' \
-    -H "Authorization: Bearer ${INPUT_TOKEN}" \
-    -H "Content-Type: application/json" \
-    -d "${comment_json}" \
-    "${comments_url}"
+  http_post "${comments_url}" "${comment_json}"
 
   exit 1
 }
@@ -101,13 +113,7 @@ create_pull_request() {
     \"base\": \"${branch}\" \
   }"
 
-  curl -XPOST -fsSL \
-    --output /dev/null \
-    -H 'Accept: application/vnd.github.v3+json' \
-    -H "Authorization: Bearer ${INPUT_TOKEN}" \
-    -H "Content-Type: application/json" \
-    -d "${pull_request}" \
-    "${pulls_url}"
+  http_post "${pulls_url}" "${pull_request}"
 }
 
 backport() {
@@ -143,7 +149,7 @@ delete_branch() {
   refs_url=$(tmp=$(jq --raw-output .pull_request.head.repo.git_refs_url "${GITHUB_EVENT_PATH}"); echo "${tmp%{*}")
 
   local status
-  status=$(curl -XDELETE -fsSL \
+  status=$(curl -XDELETE -fsL \
     --fail \
     --output /dev/null \
     -w '%{http_code}' \

spec/backport_spec.sh

@@ -25,6 +25,34 @@ Describe 'Backport action'
     The output should equal 'eC1hY2Nlc3MtdG9rZW46Z2l0aHViLXRva2Vu'
   End
 
+  Describe 'fail'
+    # mock http_post
+    http_post() {
+      echo "http_post invoked with: $*"
+    }
+    setup_event_file() {
+        cat<<EOF>"${GITHUB_EVENT_PATH}"
+{
+  "pull_request": {
+    "_links": {
+      "comments": {
+        "href": "comments-url"
+      }
+    }
+  }
+}
+EOF
+    }
+    Before 'setup_event_file'
+
+    It 'Handles reports failures'
+      When run fail message error
+      The output should equal '::error::message (error)
+http_post invoked with: comments-url {"body":"message\n\n<details><summary>Error</summary><pre>error</pre></details>"}'
+      The status should equal 1
+    End
+  End
+
   Describe 'cherry_pick'
 
     Describe 'Cherry pick succeeds'
@@ -54,9 +82,9 @@ Describe 'Backport action'
     End
 
     Describe 'Merge conflict'
-      # mock curl
-      curl() {
-        echo "CURL invoked with:$*"
+      # mock http_post
+      http_post() {
+        echo "http_post invoked with:$*"
       }
 
       setup_repo() {
@@ -117,8 +145,13 @@ EOF
       It 'Fails due to merge conflict'
         When run cherry_pick 'branch' "${git_repository}" 'backport-branch' "${merge_commit_sha}"
         The value "$(cd "${GITHUB_WORKSPACE}" && git show backport-branch:file)" should equal "conflict"
-        The output should match pattern "::error::Unable to cherry-pick commit ${merge_commit_sha} on top of branch \`branch\`.\n\nThis pull request needs to be backported manually.
-CURL invoked with:-XPOST -fsSL --output /dev/null -H Accept: application/vnd.github.v3+json -H Authorization: Bearer github-token -H Content-Type: application/json -d {\"body\":\"Unable to cherry-pick commit * on top of branch \`branch\`.\\n\\nThis pull request needs to be backported manually.\\n\\n<details><summary>Error</summary><pre>Auto-merging file\\nCONFLICT (content): Merge conflict in file\\nerror: could not apply *... Merge commit '*'\\nhint: after resolving the conflicts, mark the corrected paths\\nhint: with 'git add <paths>' or 'git rm <paths>'\\nhint: and commit the result with 'git commit'</pre></details>\"} comments-url"
+        The output should match pattern "::error::Unable to cherry-pick commit ${merge_commit_sha} on top of branch \`branch\`.\n\nThis pull request needs to be backported manually. (Auto-merging file
+CONFLICT (content): Merge conflict in file
+error: could not apply *... Merge commit '*'
+hint: after resolving the conflicts, mark the corrected paths
+hint: with 'git add <paths>' or 'git rm <paths>'
+hint: and commit the result with 'git commit')
+http_post invoked with:comments-url {\"body\":\"Unable to cherry-pick commit * on top of branch \`branch\`.\\n\\nThis pull request needs to be backported manually.\\n\\n<details><summary>Error</summary><pre>Auto-merging file\\nCONFLICT (content): Merge conflict in file\\nerror: could not apply *... Merge commit '*'\\nhint: after resolving the conflicts, mark the corrected paths\\nhint: with 'git add <paths>' or 'git rm <paths>'\\nhint: and commit the result with 'git commit'</pre></details>\"}"
         The status should equal 1
       End
     End
@@ -152,14 +185,14 @@ CURL invoked with:-XPOST -fsSL --output /dev/null -H Accept: application/vnd.git
   End
 
   Describe 'create_pull_request'
-    # mock curl
-    curl() {
-      export curl_args="$*"
+    # mock http_post
+    http_post() {
+      export http_post_args="$*"
     }
 
     It 'Creates pull requests'
       When call create_pull_request branch backport-branch title 123 url
-      The variable 'curl_args' should equal "-XPOST -fsSL --output /dev/null -H Accept: application/vnd.github.v3+json -H Authorization: Bearer ${INPUT_TOKEN} -H Content-Type: application/json -d {    \"title\": \"[Backport branch] title\",     \"body\": \"Backport of #123\",     \"head\": \"backport-branch\",     \"base\": \"branch\"   } url"
+      The variable 'http_post_args' should equal "url {    \"title\": \"[Backport branch] title\",     \"body\": \"Backport of #123\",     \"head\": \"backport-branch\",     \"base\": \"branch\"   }"
     End
   End
 
@@ -230,7 +263,7 @@ EOF
 
       It 'Deletes branches'
         When call delete_branch backport/123-to-branch
-        The value "$(cat "${curl_args}")" should equal "-XDELETE -fsSL --fail --output /dev/null -w %{http_code} -H Accept: application/vnd.github.v3+json -H Authorization: Bearer ${INPUT_TOKEN} git-refs-url/heads/backport/123-to-branch"
+        The value "$(cat "${curl_args}")" should equal "-XDELETE -fsL --fail --output /dev/null -w %{http_code} -H Accept: application/vnd.github.v3+json -H Authorization: Bearer ${INPUT_TOKEN} git-refs-url/heads/backport/123-to-branch"
       End
     End
 
@@ -246,7 +279,7 @@ EOF
 
       It 'Doesn''t fail on deleted branches'
         When call delete_branch backport/123-to-branch
-        The value "$(cat "${curl_args}")" should equal "-XDELETE -fsSL --fail --output /dev/null -w %{http_code} -H Accept: application/vnd.github.v3+json -H Authorization: Bearer ${INPUT_TOKEN} git-refs-url/heads/backport/123-to-branch"
+        The value "$(cat "${curl_args}")" should equal "-XDELETE -fsL --fail --output /dev/null -w %{http_code} -H Accept: application/vnd.github.v3+json -H Authorization: Bearer ${INPUT_TOKEN} git-refs-url/heads/backport/123-to-branch"
       End
     End