first draft

.github/workflows/test.yml

@@ -0,0 +1,21 @@
+name: test
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+jobs:
+  unit:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+    - uses: actions/checkout@v4
+    - uses: actions/setup-node@v4
+    - run: npm run docker:start
+    - run: npm install
+    - run: npm test

.gitignore

@@ -0,0 +1,4 @@
+output
+node_modules
+package-lock.json
+output_test

.npmrc

@@ -0,0 +1 @@
+ignore-scripts=true

README.md

@@ -1,2 +1,22 @@
 # open-abap-lock
-lock
+
+Concurrent/cross session locking for Open ABAP.
+
+Requires and works with PostgreSQL as the database backend, and only on the DEFAULT connection.
+
+## Notes
+
+* [PostgreSQL - Advisory Locks](https://www.postgresql.org/docs/current/explicit-locking.html#ADVISORY-LOCKS)
+* [PostgreSQL - Advisory Lock Functions](https://www.postgresql.org/docs/9.1/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS)
+
+wildcards?
+scope?
+release on crash
+table `pg_locks`
+
+## Todo
+
+* `_scope`
+* `wait` flag
+* `mode`
+* release at commit work if update task

abap_transpile.jsonc

@@ -0,0 +1,25 @@
+{
+  "input_folder": ["src", "test/src"],
+  "input_filter": [],
+  "output_folder": "output",
+  "write_unit_tests": true,
+  "write_source_map": true,
+  "libs": [
+    {
+      "url": "https://github.com/open-abap/open-abap-core"
+    }
+  ],
+  "options": {
+    "ignoreSyntaxCheck": false,
+    "addFilenames": true,
+    "addCommonJS": true,
+    "populateTables": {
+      "reposrc": false
+    },
+    "setup": {
+      "filename": "../test/setup.mjs",
+      "postFunction": "postFunction",
+      "preFunction": "preFunction"
+    }
+  }
+}

abaplint.jsonc

@@ -1,6 +1,9 @@
 {
   "global": {
-    "files": "/src/**/*.*"
+    "files": [
+      "/src/**/*.*",
+      "/test/src/**/*.*"
+    ]
   },
   "dependencies": [
     {
@@ -130,7 +133,7 @@
       "exportDynpro": true,
       "dynamicSQL": true
     },
-    "db_operation_in_loop": true,
+    "db_operation_in_loop": false,
     "definitions_top": true,
     "description_empty": false,
     "double_space": {
@@ -308,25 +311,9 @@
       "checkForms": true
     },
     "method_overwrites_builtin": true,
-    "method_parameter_names": {
-      "exclude": [],
-      "severity": "Error",
-      "patternKind": "required",
-      "ignoreNames": [],
-      "ignorePatterns": [],
-      "ignoreExceptions": true,
-      "importing": "^I._.+$",
-      "returning": "^R._.+$",
-      "changing": "^C._.+$",
-      "exporting": "^E._.+$"
-    },
+    "method_parameter_names": false,
     "mix_returning": true,
-    "modify_only_own_db_tables": {
-      "exclude": [],
-      "severity": "Error",
-      "reportDynamic": true,
-      "ownTables": "^[yz]"
-    },
+    "modify_only_own_db_tables": false,
     "msag_consistency": {
       "exclude": [],
       "severity": "Error",
@@ -548,7 +535,7 @@
     "unused_types": false,
     "unused_variables": false,
     "use_bool_expression": true,
-    "use_class_based_exceptions": true,
+    "use_class_based_exceptions": false,
     "use_line_exists": true,
     "use_new": true,
     "when_others_last": true,

package.json

@@ -0,0 +1,20 @@
+{
+  "name": "open-abap-lock",
+  "version": "1.0.0",
+  "private": true,
+  "description": "test",
+  "scripts": {
+    "lint": "abaplint",
+    "unit": "rm -rf output && abap_transpile abap_transpile.jsonc && echo RUNNING && node output/index.mjs",
+    "docker:start": "docker compose -p open-abap-lock -f test/stack.yml up -d",
+    "docker:stop": "docker compose -p open-abap-lock -f test/stack.yml down -v",
+    "test": "npm run lint && npm run unit"
+  },
+  "license": "",
+  "dependencies": {
+    "@abaplint/cli": "^2.114.6",
+    "@abaplint/runtime": "^2.12.16",
+    "@abaplint/database-pg": "^2.11.78",
+    "@abaplint/transpiler-cli": "^2.12.16"
+  }
+}

src/kernel_lock_concurrent.clas.abap

@@ -1,7 +1,131 @@
 CLASS kernel_lock_concurrent DEFINITION PUBLIC.
   PUBLIC SECTION.
+    CLASS-METHODS class_constructor.
+
+    CLASS-METHODS enqueue
+      IMPORTING
+        input        TYPE any
+        table_name   TYPE string
+        enqueue_name TYPE string
+      EXCEPTIONS
+        foreign_lock
+        system_failure.
+
+    CLASS-METHODS dequeue
+      IMPORTING
+        table_name   TYPE string
+        enqueue_name TYPE string
+        input        TYPE any.
+
+    TYPES: BEGIN OF ty_cleanup,
+             valid_locks   TYPE i,
+             cleaned_locks TYPE i,
+           END OF ty_cleanup.
+    CLASS-METHODS cleanup_locks
+      RETURNING
+        VALUE(rs_result) TYPE ty_cleanup.
+  PRIVATE SECTION.
+    CLASS-METHODS build_lock_key
+      IMPORTING
+        input              TYPE any
+        table_name         TYPE string
+      RETURNING
+        VALUE(rv_lock_key) TYPE kernel_locks-lock_key.
 ENDCLASS.
 
 CLASS kernel_lock_concurrent IMPLEMENTATION.
 
+  METHOD class_constructor.
+    cleanup_locks( ).
+  ENDMETHOD.
+
+  METHOD cleanup_locks.
+    SELECT * FROM kernel_locks INTO TABLE @DATA(lt_locks) ORDER BY PRIMARY KEY ##SUBRC_OK.
+    LOOP AT lt_locks INTO DATA(ls_lock).
+      DATA(lv_exists) = lcl_advisory=>exists( lcl_key=>encode( ls_lock-lock_key ) ).
+      IF lv_exists = abap_true.
+        rs_result-valid_locks = rs_result-valid_locks + 1.
+      ELSE.
+        DELETE FROM kernel_locks WHERE table_name = @ls_lock-table_name AND lock_key = @ls_lock-lock_key.
+        rs_result-cleaned_locks = rs_result-cleaned_locks + 1.
+      ENDIF.
+    ENDLOOP.
+  ENDMETHOD.
+
+  METHOD build_lock_key.
+
+    DATA lr_dref        TYPE REF TO data.
+    DATA lo_structdescr TYPE REF TO cl_abap_structdescr.
+    DATA lv_string      TYPE string.
+
+    FIELD-SYMBOLS <lg_row> TYPE any.
+
+    CREATE DATA lr_dref TYPE (table_name).
+    ASSIGN lr_dref->* TO <lg_row>.
+
+    lo_structdescr ?= cl_abap_typedescr=>describe_by_data( <lg_row> ).
+    ASSERT lo_structdescr IS NOT INITIAL.
+
+    LOOP AT lo_structdescr->components INTO DATA(ls_component).
+      WRITE '@KERNEL lv_string.set(input[ls_component.get().name.get().toLowerCase().trimEnd()] || "");'.
+
+      ASSIGN COMPONENT ls_component-name OF STRUCTURE <lg_row> TO FIELD-SYMBOL(<lv_row_field>).
+      ASSERT sy-subrc = 0.
+      <lv_row_field> = lv_string.
+    ENDLOOP.
+
+    rv_lock_key = <lg_row>.
+
+  ENDMETHOD.
+
+  METHOD enqueue.
+
+    DATA ls_lock_row TYPE kernel_locks.
+
+*******************
+
+    DATA(lv_lock_key) = build_lock_key(
+      input      = input
+      table_name = table_name ).
+    ASSERT lv_lock_key IS NOT INITIAL.
+
+    ls_lock_row-table_name = table_name.
+    ls_lock_row-lock_key = lv_lock_key.
+    ls_lock_row-username = sy-uname.
+    GET TIME STAMP FIELD ls_lock_row-timestamp.
+    ls_lock_row-hostname = sy-host.
+    ls_lock_row-lock_mode = ''.
+    ls_lock_row-lock_name = enqueue_name.
+
+    TRY.
+        lcl_advisory=>lock( lcl_key=>encode( ls_lock_row-lock_key ) ).
+      CATCH lcx_advisory_lock_failed.
+        RAISE foreign_lock.
+    ENDTRY.
+
+    INSERT kernel_locks FROM @ls_lock_row.
+    ASSERT sy-subrc = 0.
+
+  ENDMETHOD.
+
+  METHOD dequeue.
+
+    DATA(lv_lock_key) = build_lock_key(
+      input      = input
+      table_name = table_name ).
+
+    TRY.
+        lcl_advisory=>lock( lcl_key=>encode( lv_lock_key ) ).
+      CATCH lcx_advisory_lock_failed.
+        " it doesnt have the lock, or another session has the lock
+        RETURN.
+    ENDTRY.
+
+    DELETE FROM kernel_locks WHERE table_name = table_name AND lock_key = lv_lock_key.
+
+    " advisory locks stack,
+    lcl_advisory=>unlock( lcl_key=>encode( lv_lock_key ) ).
+    lcl_advisory=>unlock( lcl_key=>encode( lv_lock_key ) ).
+  ENDMETHOD.
+
 ENDCLASS.