Improve Mattermost OIDC mobile bridge installer

install-update-oidc-mobile-bridge.sh

@@ -35,6 +35,7 @@ SYMLINK_CHANGED=false
 UNIT_CREATED=false
 ROLLBACK_TARGET=""
 LEGACY_BRIDGE_BACKUP=""
+REINSTALL_BRIDGE_BACKUP=""
 
 
 # ----------
@@ -162,6 +163,7 @@ ask_yes_no() {
 rollback_bridge() {
    local rollback_failed=false
    local rollback_path=""
+   local rollback_tmp_link="${MM_BRIDGE_LINK}.rollback.$$"
 
    [[ "$SYMLINK_CHANGED" = true ]] || return 0
 
@@ -189,11 +191,12 @@ rollback_bridge() {
 
       if [[ "$rollback_failed" = true ]]; then
          error "Initial-install cleanup was not fully successful. Please check '${MM_BRIDGE_LINK}', '${MM_BRIDGE_SERVICE}' and nginx manually."
+         return 1
       else
          info "Initial activation was removed. The new binary, source directory and unit file were kept for analysis."
-      fi
          return 0
       fi
+   fi
 
    warn "The new bridge did not pass all checks. Trying to restore the previous installation."
 
@@ -205,25 +208,85 @@ rollback_bridge() {
       fi
    fi
 
-   if [[ -n "$ROLLBACK_TARGET" && -e "$rollback_path" ]]; then
+   # A same-version reinstall replaces the file referenced by ROLLBACK_TARGET.
-      ln -s "$ROLLBACK_TARGET" "${MM_BRIDGE_LINK}.rollback.$$" >> "$log_file" 2>&1 \
+   # Restore that saved binary first; changing the symlink alone would otherwise
-         && mv -Tf "${MM_BRIDGE_LINK}.rollback.$$" "$MM_BRIDGE_LINK" >> "$log_file" 2>&1 \
+   # still point to the newly installed (and possibly broken) binary.
-         || rollback_failed=true
+   if [[ -n "$REINSTALL_BRIDGE_BACKUP" ]]; then
-   elif [[ -n "$LEGACY_BRIDGE_BACKUP" && -f "$LEGACY_BRIDGE_BACKUP" ]]; then
+      echononl "Restore previous same-version bridge binary.."
-      rm -f "$MM_BRIDGE_LINK" >> "$log_file" 2>&1
+      _restore_tmp="${MM_BRIDGE_BIN}.restore.$$"
-      cp -a "$LEGACY_BRIDGE_BACKUP" "$MM_BRIDGE_LINK" >> "$log_file" 2>&1 || rollback_failed=true
+      rm -f "$_restore_tmp"
+
+      if [[ -f "$REINSTALL_BRIDGE_BACKUP" ]] \
+         && cp -a "$REINSTALL_BRIDGE_BACKUP" "$_restore_tmp" >> "$log_file" 2>&1 \
+         && mv -Tf "$_restore_tmp" "$MM_BRIDGE_BIN" >> "$log_file" 2>&1 ; then
+         echo_ok
       else
+         rm -f "$_restore_tmp"
+         echo_failed
+         error "Could not restore '${REINSTALL_BRIDGE_BACKUP}' to '${MM_BRIDGE_BIN}'."
          rollback_failed=true
       fi
+   fi
 
    if [[ "$rollback_failed" = false ]]; then
-      systemctl restart "$MM_BRIDGE_SERVICE" >> "$log_file" 2>&1 || rollback_failed=true
+      if [[ -n "$ROLLBACK_TARGET" && -e "$rollback_path" ]]; then
+         echononl "Restore previous stable bridge symlink.."
+         rm -f "$rollback_tmp_link"
+         if ln -s "$ROLLBACK_TARGET" "$rollback_tmp_link" >> "$log_file" 2>&1 \
+            && mv -Tf "$rollback_tmp_link" "$MM_BRIDGE_LINK" >> "$log_file" 2>&1 ; then
+            echo_ok
+         else
+            rm -f "$rollback_tmp_link"
+            echo_failed
+            error "Could not restore stable bridge symlink '${MM_BRIDGE_LINK}' -> '${ROLLBACK_TARGET}'."
+            rollback_failed=true
+         fi
+      elif [[ -n "$LEGACY_BRIDGE_BACKUP" && -f "$LEGACY_BRIDGE_BACKUP" ]]; then
+         echononl "Restore previous legacy bridge binary.."
+         if rm -f "$MM_BRIDGE_LINK" >> "$log_file" 2>&1 \
+            && cp -a "$LEGACY_BRIDGE_BACKUP" "$MM_BRIDGE_LINK" >> "$log_file" 2>&1 ; then
+            echo_ok
+         else
+            echo_failed
+            error "Could not restore legacy bridge binary from '${LEGACY_BRIDGE_BACKUP}'."
+            rollback_failed=true
+         fi
+      else
+         error "No usable rollback target was found."
+         rollback_failed=true
+      fi
+   fi
+
+   if [[ "$rollback_failed" = false ]]; then
+      echononl "Restart previous Mattermost OIDC Mobile Bridge service.."
+      if systemctl restart "$MM_BRIDGE_SERVICE" >> "$log_file" 2>&1 ; then
+         echo_ok
+      else
+         echo_failed
+         error "Could not restart '${MM_BRIDGE_SERVICE}' after rollback."
+         rollback_failed=true
+      fi
+   fi
+
+   if [[ "$NGINX_CHANGED" = true && -n "$NGINX_BACKUP" && -f "$NGINX_BACKUP" ]]; then
+      echononl "Restore previous nginx configuration.."
+      if cp -a "$NGINX_BACKUP" "$NGINX_CONFIG_FILE" >> "$log_file" 2>&1 \
+         && nginx -t >> "$log_file" 2>&1 \
+         && systemctl reload nginx.service >> "$log_file" 2>&1 ; then
+         echo_ok
+      else
+         echo_failed
+         error "Could not fully restore/reload the previous nginx configuration. Check nginx manually."
+         rollback_failed=true
+      fi
    fi
 
    if [[ "$rollback_failed" = true ]]; then
-      error "Automatic rollback failed. Please check '${MM_BRIDGE_LINK}' and '${MM_BRIDGE_SERVICE}' manually."
+      error "Automatic rollback failed. Please check the bridge installation, '${MM_BRIDGE_SERVICE}' and nginx configuration manually."
+      return 1
    else
       info "Previous bridge installation was restored and restarted."
+      return 0
    fi
 }
 
@@ -777,7 +840,14 @@ blank_line
 
 if [[ -e "$MM_BRIDGE_BIN" ]]; then
    echononl "Backup existing bridge binary.."
-   if mv "$MM_BRIDGE_BIN" "${MM_BRIDGE_BIN}.${backup_date}" > "$log_file" 2>&1 ; then
+   _bridge_binary_backup="${MM_BRIDGE_BIN}.${backup_date}"
+   if mv "$MM_BRIDGE_BIN" "$_bridge_binary_backup" > "$log_file" 2>&1 ; then
+      # During a same-version reinstall this backup is the actual rollback
+      # payload. ROLLBACK_TARGET alone is insufficient because it names the
+      # same versioned path that is about to be replaced.
+      if [[ "$INSTALLATION_MODE" = "upgrade" && "$MM_NEW_VERSION" = "$MM_CURRENT_VERSION" ]]; then
+         REINSTALL_BRIDGE_BACKUP="$_bridge_binary_backup"
+      fi
       echo_ok
    else
       echo_failed
@@ -797,6 +867,25 @@ else
    fatal "$(cat "$log_file")"
 fi
 
+# On an initial installation the systemd unit below already references the
+# stable bridge symlink. Create that symlink before systemd-analyze verifies
+# the unit. During upgrades, keep the existing symlink untouched until the
+# final activation step.
+if [[ "$INSTALLATION_MODE" = "initial-installation" ]]; then
+   echononl "Create initial stable bridge symlink.."
+   _tmp_link="${MM_BRIDGE_LINK}.new.$$"
+   rm -f "$_tmp_link"
+   if ln -s "${MM_BRIDGE_NAME}-${MM_NEW_VERSION}" "$_tmp_link" > "$log_file" 2>&1 \
+      && mv -Tf "$_tmp_link" "$MM_BRIDGE_LINK" >> "$log_file" 2>&1 ; then
+      SYMLINK_CHANGED=true
+      echo_ok
+   else
+      rm -f "$_tmp_link"
+      echo_failed
+      fatal "$(cat "$log_file")"
+   fi
+fi
+
 # Preserve an old unversioned installation before replacing it with a symlink.
 if [[ "$INSTALLATION_MODE" = "legacy-upgrade" ]]; then
    LEGACY_BRIDGE_BACKUP="${MM_BRIDGE_LINK}.${backup_date}"
@@ -898,6 +987,20 @@ else
 fi
 
 
+# Ensure that the bridge service is enabled also when an existing unit is reused.
+echononl "Ensure '${MM_BRIDGE_SERVICE}' is enabled.."
+if systemctl is-enabled --quiet "$MM_BRIDGE_SERVICE" 2>/dev/null ; then
+   echo_ok
+else
+   if systemctl enable "$MM_BRIDGE_SERVICE" > "$log_file" 2>&1 ; then
+      echo_ok
+   else
+      echo_failed
+      fatal "$(cat "$log_file")"
+   fi
+fi
+
+
 # ----------
 # Configure nginx if requested
 # ----------
@@ -991,7 +1094,7 @@ NGINX_MOBILE_EOF
          fi
 
          echononl "Insert missing bridge locations before Mattermost 'location /'.."
-         python3 - "$NGINX_CONFIG_FILE" "$NGINX_INSERT_FILE" "$MM_BRIDGE_UPSTREAM" <<'PY_EOF' > "$log_file" 2>&1
+         python3 - "$NGINX_CONFIG_FILE" "$NGINX_INSERT_FILE" "$MM_BRIDGE_UPSTREAM" "$_mm_site_host" <<'PY_EOF' > "$log_file" 2>&1
 import re
 import sys
 from pathlib import Path
@@ -999,6 +1102,7 @@ from pathlib import Path
 config = Path(sys.argv[1])
 insert = Path(sys.argv[2]).read_text()
 upstream = sys.argv[3].rstrip("/")
+site_host = sys.argv[4].strip()
 text = config.read_text()
 
 def matching_brace(data, open_pos):
@@ -1032,25 +1136,53 @@ def matching_brace(data, open_pos):
                 return pos
     return None
 
-servers = []
+all_servers = []
 for match in re.finditer(r'(?m)^[ \t]*server[ \t]*\{', text):
     open_pos = text.find("{", match.start(), match.end())
     close_pos = matching_brace(text, open_pos)
     if close_pos is None:
         raise SystemExit("Could not parse nginx server block")
     body = text[open_pos + 1:close_pos]
+    all_servers.append((open_pos + 1, close_pos, body))
+
+def general_locations(body):
+    return list(re.finditer(r'(?m)^[ \t]*location[ \t]+/[ \t]*\{', body))
+
+# Prefer the Mattermost vHost identified by SiteURL/server_name. This works
+# with both direct proxy_pass targets and named nginx upstreams. The HTTP
+# redirect vHost is excluded because it has no general "location /" block.
+servers = []
+if site_host:
+    for server in all_servers:
+        body = server[2]
+        names = []
+        for match in re.finditer(r'(?m)^[ \t]*server_name[ \t]+([^;]+);', body):
+            names.extend(match.group(1).split())
+        if site_host in names and len(general_locations(body)) == 1:
+            servers.append(server)
+
+# Fallback for installations where SiteURL is unavailable: retain the old
+# direct-upstream detection.
+if not servers:
     proxy_re = re.compile(r'proxy_pass\s+' + re.escape(upstream) + r'/?\s*;')
-    if proxy_re.search(body):
+    servers = [
-        servers.append((open_pos + 1, close_pos, body))
+        server for server in all_servers
+        if proxy_re.search(server[2]) and len(general_locations(server[2])) == 1
+    ]
 
 if len(servers) != 1:
-    raise SystemExit(f"Expected exactly one server block proxying to {upstream}, found {len(servers)}")
+    if site_host:
+        raise SystemExit(
+            f"Expected exactly one Mattermost server block for server_name "
+            f"{site_host} with a general 'location /', found {len(servers)}"
+        )
+    raise SystemExit(
+        f"Expected exactly one server block proxying to {upstream} "
+        f"with a general 'location /', found {len(servers)}"
+    )
 
 body_start, body_end, body = servers[0]
-locations = list(re.finditer(r'(?m)^[ \t]*location[ \t]+/[ \t]*\{', body))
+locations = general_locations(body)
-if len(locations) != 1:
-    raise SystemExit(f"Expected exactly one general 'location /' in Mattermost server block, found {len(locations)}")
-
 insert_pos = body_start + locations[0].start()
 text = text[:insert_pos] + insert + text[insert_pos:]
 config.write_text(text)
@@ -1089,6 +1221,12 @@ blank_line
 echo -e "\033[37m\033[1mActivate Mattermost OIDC Mobile Bridge..\033[m"
 blank_line
 
+if [[ "$INSTALLATION_MODE" = "initial-installation" ]] \
+   && [[ -L "$MM_BRIDGE_LINK" ]] \
+   && [[ "$(readlink "$MM_BRIDGE_LINK")" = "${MM_BRIDGE_NAME}-${MM_NEW_VERSION}" ]]; then
+   echononl "Keep initial stable bridge symlink to '${MM_BRIDGE_NAME}-${MM_NEW_VERSION}'.."
+   echo_ok
+else
    echononl "Switch stable bridge symlink to '${MM_BRIDGE_NAME}-${MM_NEW_VERSION}'.."
    _tmp_link="${MM_BRIDGE_LINK}.new.$$"
    rm -f "$_tmp_link"
@@ -1101,6 +1239,7 @@ else
       echo_failed
       fatal "$(cat "$log_file")"
    fi
+fi
 
 if [[ "$NGINX_CHANGED" = true ]]; then
    echononl "Reload nginx service.."
@@ -1109,14 +1248,32 @@ if [[ "$NGINX_CHANGED" = true ]]; then
    else
       echo_failed
       error "nginx reload failed. Restoring the previous nginx configuration."
+
+      nginx_rollback_failed=false
+
       cp -a "$NGINX_CONFIG_FILE" "${NGINX_CONFIG_FILE}.failed-${backup_date}" 2>/dev/null || true
-      if cp -a "$NGINX_BACKUP" "$NGINX_CONFIG_FILE" >> "$log_file" 2>&1          && nginx -t >> "$log_file" 2>&1          && systemctl reload nginx.service >> "$log_file" 2>&1 ; then
+
+      if cp -a "$NGINX_BACKUP" "$NGINX_CONFIG_FILE" >> "$log_file" 2>&1 \
+         && nginx -t >> "$log_file" 2>&1 \
+         && systemctl reload nginx.service >> "$log_file" 2>&1 ; then
          info "Previous nginx configuration was restored and reloaded."
+         NGINX_CHANGED=false
       else
          error "Could not fully restore/reload the previous nginx configuration. Check nginx manually."
+         nginx_rollback_failed=true
+      fi
+
+      if rollback_bridge ; then
+         bridge_rollback_failed=false
+      else
+         bridge_rollback_failed=true
+      fi
+
+      if [[ "$nginx_rollback_failed" = false && "$bridge_rollback_failed" = false ]]; then
+         fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed because nginx could not be reloaded.\n             The previous nginx configuration and bridge installation were successfully restored."
+      else
+         fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed because nginx could not be reloaded.\n             The previous system state could not be fully restored.\n\n             Manual intervention is required."
       fi
-      rollback_bridge
-      fatal "nginx reload failed after adding the Mattermost OIDC Mobile Bridge locations."
    fi
 fi
 
@@ -1125,20 +1282,29 @@ if systemctl restart "$MM_BRIDGE_SERVICE" > "$log_file" 2>&1 ; then
    echo_ok
 else
    echo_failed
-   rollback_bridge
+   if rollback_bridge ; then
-   fatal "Failed to restart '${MM_BRIDGE_SERVICE}'."
+      fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed because '${MM_BRIDGE_SERVICE}' could not be restarted.\n             The previous bridge installation was successfully restored."
+   else
+      fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed because '${MM_BRIDGE_SERVICE}' could not be restarted.\n             The previous installation could not be restored.\n\n             Manual intervention is required."
+   fi
 fi
 
 if ! bridge_test ; then
-   rollback_bridge
+   if rollback_bridge ; then
-   fatal "Mattermost OIDC Mobile Bridge functional test failed."
+      fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed.\n             The previous bridge installation was successfully restored."
+   else
+      fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed\n             and the previous installation could not be restored.\n\n             Manual intervention is required."
+   fi
 fi
 
 if [[ -n "$NGINX_CONFIG_FILE" ]]; then
    if [[ -n "$MM_SITE_URL" ]]; then
       if ! nginx_e2e_test ; then
-         rollback_bridge
+         if rollback_bridge ; then
-         fatal "Mattermost OIDC Mobile Bridge end-to-end test through nginx failed."
+            fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed during the nginx end-to-end test.\n             The previous bridge installation was successfully restored."
+         else
+            fatal "Installation of Mattermost OIDC Mobile Bridge ${MM_NEW_VERSION} failed during the nginx end-to-end test\n             and the previous installation could not be restored.\n\n             Manual intervention is required."
+         fi
       fi
    else
       warn "Mattermost SiteURL could not be read from '${MM_CONFIG_FILE}'. End-to-end nginx tests were skipped."
@@ -1146,6 +1312,27 @@ if [[ -n "$NGINX_CONFIG_FILE" ]]; then
 fi
 
 
+# ----------
+# Remove redundant same-version backup after successful tests
+# ----------
+
+if [[ -n "$REINSTALL_BRIDGE_BACKUP" && -f "$REINSTALL_BRIDGE_BACKUP" ]]; then
+   if cmp -s "$REINSTALL_BRIDGE_BACKUP" "$MM_BRIDGE_BIN"; then
+      echononl "Remove identical same-version bridge backup.."
+      if rm -f "$REINSTALL_BRIDGE_BACKUP" > "$log_file" 2>&1 ; then
+         echo_ok
+         REINSTALL_BRIDGE_BACKUP=""
+      else
+         echo_failed
+         warn "Could not remove redundant bridge backup '${REINSTALL_BRIDGE_BACKUP}'."
+      fi
+   else
+      echononl "Keep different same-version bridge backup.."
+      echo_ok
+   fi
+fi
+
+
 # ----------
 # Final information
 # ----------