[IMP] add --resume-from option

to resume the migration process from a step wehre the database and
filestore are correct.

README.md

@@ -9,6 +9,7 @@ A tool for migrating Odoo databases between major versions, using [OpenUpgrade](
 - [Project Structure](#project-structure)
 - [How It Works](#how-it-works)
 - [Usage](#usage)
+- [Resuming a Failed Migration](#resuming-a-failed-migration)
 - [Customization](#customization)
 - [Troubleshooting](#troubleshooting)
 
@@ -158,7 +159,7 @@ The script performs a **step-by-step migration** between each major version. For
 ### Running the Migration
 
 ```bash
-./upgrade.sh <source_version> <target_version> <database_name> <source_service>
+./upgrade.sh <source_version> <target_version> <database_name> <source_service> [--resume-from|-r <version>]
 ```
 
 **Parameters:**
@@ -169,6 +170,11 @@ The script performs a **step-by-step migration** between each major version. For
 | `database_name` | Database name | `my_prod_db` |
 | `source_service` | Source Docker Compose service | `odoo14` |
 
+**Options:**
+| Option | Description |
+|--------|-------------|
+| `--resume-from <version>`, `-r <version>` | Resume from an intermediate checkpoint (see [Resuming a Failed Migration](#resuming-a-failed-migration)) |
+
 **Example:**
 ```bash
 ./upgrade.sh 14 17 elabore_20241208 odoo14
@@ -239,6 +245,48 @@ compose run odoo17 shell -d ou17 --no-http --stop-after-init < lib/python/valida
 - **JSON report** written to `/tmp/validation_views_<db>_<timestamp>.json`
 - **Exit code**: `0` = success, `1` = errors found
 
+## Resuming a Failed Migration
+
+Each version hop copies the database before modifying it (`ou14` → `ou15` → `ou16` → …). If a migration crashes mid-way, the intermediate databases from completed hops are still intact and can be used as a restart point.
+
+### How It Works
+
+Use `--resume-from <version>` (or `-r <version>`) to restart from an intermediate checkpoint:
+
+```bash
+./upgrade.sh <source_version> <target_version> <database_name> <source_service> --resume-from <checkpoint_version>
+```
+
+When a checkpoint is specified, the script:
+- **Skips** the initial database and filestore copy
+- **Skips** `prepare_db.sh` (already done before the crash)
+- **Starts the migration loop** from `checkpoint_version + 1`
+
+### Example
+
+A migration from 14 to 18 crashes during the 16→17 hop. The database `ou15` was successfully created. Resume from there:
+
+```bash
+./upgrade.sh 14 18 my_database odoo14 --resume-from 15
+```
+
+This runs: `16.0 → 17.0 → 18.0`, starting from `ou15`.
+
+### Constraints
+
+- The checkpoint version must be strictly between the source and target versions.
+- The intermediate database (`ou<version>`) and its filestore must exist before resuming.
+
+### Restarting From Scratch
+
+To restart a full migration from the beginning (ignoring all intermediate databases):
+
+```bash
+./upgrade.sh 14 18 my_database odoo14
+```
+
+The script automatically drops and recreates the final target database (`ou18`) if it already exists.
+
 ## Customization
 
 ### Version Scripts

upgrade.sh

@@ -10,7 +10,7 @@ source "${SCRIPT_DIR}/lib/common.sh"
 
 usage() {
     cat <<EOF >&2
-Usage: $0 <origin_version> <final_version> <db_name> <service_name>
+Usage: $0 <origin_version> <final_version> <db_name> <service_name> [--resume-from|-r <version>]
 
 Arguments:
     origin_version   Origin Odoo version number (e.g., 12 for version 12.0)
@@ -18,14 +18,22 @@ Arguments:
     db_name          Name of the database to migrate
     service_name     Name of the origin Odoo service (docker compose service)
 
-Example:
+Options:
-    $0 14 16 elabore_20241208 odoo14
+    --resume-from, -r <version>
+                     Resume migration from an already-migrated intermediate
+                     database (e.g., ou15). Skips the initial DB copy and
+                     prepare_db.sh phases. The intermediate DB must exist.
+
+Examples:
+    $0 14 18 elabore_20241208 odoo14
+    $0 14 18 elabore_20241208 odoo14 --resume-from 15
+    $0 14 18 elabore_20241208 odoo14 -r 15
 EOF
     exit 1
 }
 
 if [[ $# -lt 4 ]]; then
-    log_error "Missing arguments. Expected 4, got $#."
+    log_error "Missing arguments. Expected at least 4, got $#."
     usage
 fi
 
@@ -38,11 +46,50 @@ readonly FINAL_VERSION
 readonly ORIGIN_DB_NAME="$3"
 readonly ORIGIN_SERVICE_NAME="$4"
 
+# Parse optional --resume-from / -r flag
+RESUME_FROM_VERSION=""
+shift 4
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --resume-from|-r)
+            if [[ $# -lt 2 ]]; then
+                log_error "Option '$1' requires a version number argument."
+                usage
+            fi
+            RESUME_FROM_VERSION="$2"
+            shift 2
+            ;;
+        *)
+            log_error "Unknown option: '$1'"
+            usage
+            ;;
+    esac
+done
+readonly RESUME_FROM_VERSION
+
 readonly COPY_DB_NAME="ou${ORIGIN_VERSION}"
 export FINALE_DB_NAME="ou${FINAL_VERSION}"
 readonly FINALE_DB_NAME
 readonly FINALE_SERVICE_NAME="${FINALE_DB_NAME}"
 
+# Validate --resume-from value if provided
+if [[ -n "$RESUME_FROM_VERSION" ]]; then
+    if ! [[ "$RESUME_FROM_VERSION" =~ ^[0-9]+$ ]]; then
+        log_error "--resume-from value must be a numeric version number (got: '$RESUME_FROM_VERSION')."
+        exit 1
+    fi
+    if [[ "$RESUME_FROM_VERSION" -le "$ORIGIN_VERSION" ]]; then
+        log_error "--resume-from ($RESUME_FROM_VERSION) must be strictly greater than origin version ($ORIGIN_VERSION)."
+        log_error "To start a fresh migration, run without --resume-from."
+        exit 1
+    fi
+    if [[ "$RESUME_FROM_VERSION" -ge "$FINAL_VERSION" ]]; then
+        log_error "--resume-from ($RESUME_FROM_VERSION) must be strictly less than final version ($FINAL_VERSION)."
+        log_error "Nothing to migrate: checkpoint is at or beyond the target version."
+        exit 1
+    fi
+fi
+
 readarray -t postgres_containers < <(docker ps --format '{{.Names}}' | grep postgres || true)
 
 if [[ ${#postgres_containers[@]} -eq 0 ]]; then
@@ -61,8 +108,13 @@ readonly POSTGRES_SERVICE_NAME
 log_step "INPUT PARAMETERS"
 log_info "Origin version .......... $ORIGIN_VERSION"
 log_info "Final version ........... $FINAL_VERSION"
-log_info "Origin DB name ........... $ORIGIN_DB_NAME"
+log_info "Origin DB name .......... $ORIGIN_DB_NAME"
 log_info "Origin service name ..... $ORIGIN_SERVICE_NAME"
+if [[ -n "$RESUME_FROM_VERSION" ]]; then
+    log_info "Resume from version ..... $RESUME_FROM_VERSION (ou${RESUME_FROM_VERSION})"
+else
+    log_info "Resume from version ..... none (full migration)"
+fi
 
 log_step "COMPUTED GLOBAL VARIABLES"
 log_info "Copy DB name ............. $COPY_DB_NAME"
@@ -74,20 +126,42 @@ log_info "Postgres service name .... $POSTGRES_SERVICE_NAME"
 
 log_step "CHECKS ALL NEEDED COMPONENTS ARE AVAILABLE"
 
-db_exists=$(docker exec -it -u 70 "$POSTGRES_SERVICE_NAME" psql -tc "SELECT 1 FROM pg_database WHERE datname = '$ORIGIN_DB_NAME'" | tr -d '[:space:]')
+if [[ -n "$RESUME_FROM_VERSION" ]]; then
-if [[ "$db_exists" ]]; then
+    readonly RESUME_DB_NAME="ou${RESUME_FROM_VERSION}"
-    log_info "Database '$ORIGIN_DB_NAME' found."
-else
-    log_error "Database '$ORIGIN_DB_NAME' not found in the local postgres service. Please add it and restart the upgrade process."
-    exit 1
-fi
 
-filestore_path="${DATASTORE_PATH}/${ORIGIN_SERVICE_NAME}/${FILESTORE_SUBPATH}/${ORIGIN_DB_NAME}"
+    resume_db_exists=$(docker exec -u 70 "$POSTGRES_SERVICE_NAME" psql -tc "SELECT 1 FROM pg_database WHERE datname = '${RESUME_DB_NAME}'" | tr -d '[:space:]')
-if [[ -d "$filestore_path" ]]; then
+    if [[ "$resume_db_exists" ]]; then
-    log_info "Filestore '$filestore_path' found."
+        log_info "Checkpoint database '${RESUME_DB_NAME}' found."
+    else
+        log_error "Checkpoint database '${RESUME_DB_NAME}' not found in the local postgres service."
+        log_error "Ensure the migration up to version ${RESUME_FROM_VERSION} completed successfully before resuming."
+        exit 1
+    fi
+
+    resume_filestore_path="${DATASTORE_PATH}/${RESUME_DB_NAME}/${FILESTORE_SUBPATH}/${RESUME_DB_NAME}"
+    if [[ -d "$resume_filestore_path" ]]; then
+        log_info "Checkpoint filestore '${resume_filestore_path}' found."
+    else
+        log_error "Checkpoint filestore '${resume_filestore_path}' not found."
+        log_error "Ensure the filestore for '${RESUME_DB_NAME}' is intact before resuming."
+        exit 1
+    fi
 else
-    log_error "Filestore '$filestore_path' not found, please add it and restart the upgrade process."
+    db_exists=$(docker exec -u 70 "$POSTGRES_SERVICE_NAME" psql -tc "SELECT 1 FROM pg_database WHERE datname = '$ORIGIN_DB_NAME'" | tr -d '[:space:]')
-    exit 1
+    if [[ "$db_exists" ]]; then
+        log_info "Database '$ORIGIN_DB_NAME' found."
+    else
+        log_error "Database '$ORIGIN_DB_NAME' not found in the local postgres service. Please add it and restart the upgrade process."
+        exit 1
+    fi
+
+    filestore_path="${DATASTORE_PATH}/${ORIGIN_SERVICE_NAME}/${FILESTORE_SUBPATH}/${ORIGIN_DB_NAME}"
+    if [[ -d "$filestore_path" ]]; then
+        log_info "Filestore '$filestore_path' found."
+    else
+        log_error "Filestore '$filestore_path' not found, please add it and restart the upgrade process."
+        exit 1
+    fi
 fi
 
 log_step "LAUNCH VIRGIN ODOO IN FINAL VERSION"
@@ -102,24 +176,36 @@ run_compose --debug run "$FINALE_SERVICE_NAME" -i base --stop-after-init --no-ht
 
 log_info "Model database in final Odoo version created."
 
-log_step "COPY ORIGINAL COMPONENTS"
+if [[ -z "$RESUME_FROM_VERSION" ]]; then
+    log_step "COPY ORIGINAL COMPONENTS"
 
-copy_database "$ORIGIN_DB_NAME" "$COPY_DB_NAME" "$COPY_DB_NAME"
+    copy_database "$ORIGIN_DB_NAME" "$COPY_DB_NAME" "$COPY_DB_NAME"
-log_info "Original database copied to ${COPY_DB_NAME}@${COPY_DB_NAME}."
+    log_info "Original database copied to ${COPY_DB_NAME}@${COPY_DB_NAME}."
 
-copy_filestore "$ORIGIN_SERVICE_NAME" "$ORIGIN_DB_NAME" "$COPY_DB_NAME" "$COPY_DB_NAME"
+    copy_filestore "$ORIGIN_SERVICE_NAME" "$ORIGIN_DB_NAME" "$COPY_DB_NAME" "$COPY_DB_NAME"
-log_info "Original filestore copied."
+    log_info "Original filestore copied."
+else
+    log_step "COPY ORIGINAL COMPONENTS — SKIPPED (resuming from checkpoint ou${RESUME_FROM_VERSION})"
+fi
 
 
 log_step "PATH OF MIGRATION"
 
-readarray -t versions < <(seq $((ORIGIN_VERSION + 1)) "$FINAL_VERSION")
+if [[ -n "$RESUME_FROM_VERSION" ]]; then
-log_info "Migration path is ${versions[*]}"
+    readarray -t versions < <(seq $((RESUME_FROM_VERSION + 1)) "$FINAL_VERSION")
+    log_info "Resuming migration from ou${RESUME_FROM_VERSION} — path is ${versions[*]}"
+else
+    readarray -t versions < <(seq $((ORIGIN_VERSION + 1)) "$FINAL_VERSION")
+    log_info "Migration path is ${versions[*]}"
+fi
 
 
-log_step "DATABASE PREPARATION"
+if [[ -z "$RESUME_FROM_VERSION" ]]; then
-
+    log_step "DATABASE PREPARATION"
-"${SCRIPT_DIR}/scripts/prepare_db.sh" "$COPY_DB_NAME" "$COPY_DB_NAME" "$FINALE_DB_NAME" "$FINALE_SERVICE_NAME"
+    "${SCRIPT_DIR}/scripts/prepare_db.sh" "$COPY_DB_NAME" "$COPY_DB_NAME" "$FINALE_DB_NAME" "$FINALE_SERVICE_NAME"
+else
+    log_step "DATABASE PREPARATION — SKIPPED (resuming from checkpoint ou${RESUME_FROM_VERSION})"
+fi
 
 
 log_step "UPGRADE PROCESS"