./discourse-setup が SMTP ユーザー名を SMTP パスワードの先頭に配置する

also LLM/AI generated

Got it — no Ruby/Python on the host. Here’s a pure Bash + awk patch that:
• builds a percent-encoded SMTP_URL using only Bash (byte-wise loop; no Python),
• inserts or replaces SMTP_URL under the env: block using awk (no sed),
• removes the per-key DISCOURSE_SMTP_* lines (safe anchored deletes),
• adds a tiny sanity check using grep/awk only.

Apply with git apply -p0 in the discourse_docker repo.

--- a/discourse-setup
+++ b/discourse-setup
@@ -867,6 +867,130 @@ write_smtp_settings() {
   local app_yml="containers/app.yml"
   [[ -f "$app_yml" ]] || die "Cannot find $app_yml. Did you run bootstrap?"

+  ##############################################
+  # Pure-Bash URL encoder for SMTP credentials #
+  ##############################################
+  # Encodes everything except A-Z a-z 0-9 . _ ~ -
+  # Works byte-by-byte; requires bash and printf.
+  urlencode_cred() {
+    local s="$1" out= i ch o
+    # set C locale to get byte semantics
+    LC_ALL=C
+    for ((i=0; i<${#s}; i++)); do
+      ch="${s:i:1}"
+      case "$ch" in
+        [A-Za-z0-9._~-])
+          out+="$ch"
+          ;;
+        *)
+          # Get byte value: print char, read with od, then format %HH
+          # Avoid external heavy deps; od is in coreutils / busybox.
+          o=$(printf '%s' "$ch" | od -An -tu1 | awk '{$1=$1;print $1}')
+          # If od somehow failed (empty), fall back to hex via printf %02X of first byte
+          if [ -z "$o" ]; then
+            o=$(printf '%s' "$ch" | head -c1 | od -An -tu1 | awk '{$1=$1;print $1}')
+          fi
+          printf -v o '%%%02X' "$o"
+          out+="$o"
+          ;;
+      esac
+    done
+    printf '%s' "$out"
+  }
+
+  # Build SMTP_URL (single line) from collected answers
+  # These vars are gathered earlier in discourse-setup:
+  #   $smtp_address  $smtp_port  $smtp_user  $smtp_password
+  local addr="$smtp_address"
+  local port="$smtp_port"
+  local user_enc pass_enc
+  user_enc="$(urlencode_cred "$smtp_user")"
+  pass_enc="$(urlencode_cred "$smtp_password")"
+  local smtp_url="smtp://${user_enc}:${pass_enc}@${addr}:${port}"
+
+  ########################################################
+  # YAML-safe edit via awk (no sed / no external runtimes)
+  # - ensure env: exists
+  # - insert or replace SMTP_URL under env:
+  # - remove DISCOURSE_SMTP_* keys
+  ########################################################
+  awk -v NEWVAL="$smtp_url" '
+    BEGIN{
+      have_env=0; in_env=0; inserted=0
+    }
+    # detect env: line at top level (start of line, possibly indented 0..)
+    # we’ll consider two-space indentation for children.
+    /^[[:space:]]*env:[[:space:]]*$/ {
+      print; have_env=1; in_env=1; next
+    }
+    # leaving env: block when indentation returns to 0 or next top-level key
+    in_env && /^[^[:space:]]/ {
+      if (!inserted) {
+        print "  SMTP_URL: \"" NEWVAL "\""
+        inserted=1
+      }
+      in_env=0
+    }
+    # while in env:, handle replacements and deletions
+    in_env {
+      # drop per-key DISCOURSE_SMTP_* lines entirely
+      if ($0 ~ /^[[:space:]]*DISCOURSE_SMTP_(ADDRESS|PORT|USER_NAME|PASSWORD):/) next
+      # replace existing SMTP_URL line
+      if ($0 ~ /^[[:space:]]*SMTP_URL:[[:space:]]*/) {
+        print "  SMTP_URL: \"" NEWVAL "\""
+        inserted=1
+        next
+      }
+      print
+      next
+    }
+    { print }
+    END{
+      # If env: never existed, append it with the key
+      if (!have_env) {
+        print ""
+        print "env:"
+        print "  SMTP_URL: \"" NEWVAL "\""
+      } else if (in_env && !inserted) {
+        # env: existed and we were still in it at EOF
+        print "  SMTP_URL: \"" NEWVAL "\""
+      }
+    }
+  ' "$app_yml" > "$app_yml.tmp.$$" && mv "$app_yml.tmp.$$" "$app_yml"
+
+  ##############################################
+  # Sanity check: basic guard against mangling #
+  ##############################################
+  # 1) SMTP_URL present
+  grep -q '^[[:space:]]*SMTP_URL:' "$app_yml" || die "SMTP_URL not written to $app_yml"
+  # 2) password not prefixed by username (classic failure signature)
+  awk '
+    BEGIN{ok=1}
+    /^[[:space:]]*SMTP_URL:[[:space:]]*"/{
+      line=$0
+      gsub(/^[[:space:]]*SMTP_URL:[[:space:]]*"/,"",line)
+      gsub(/".*$/,"",line)
+      # Extract creds before @ and after scheme
+      # e.g. smtp://user:pass@host:port
+      sub(/^[a-z]+:\/\//,"",line)
+      at=index(line,"@")
+      if (at>0) {
+        creds=substr(line,1,at-1)
+        colon=index(creds,":")
+        if (colon>0) {
+          user=substr(creds,1,colon-1)
+          pass=substr(creds,colon+1)
+          if (index(pass,user)==1) { ok=0 }
+        }
+      }
+    }
+    END{ if (!ok) { print "Password appears prefixed by username"; exit 1 } }
+  ' "$app_yml"
 }
 
-  # Write per-key SMTP entries (address/port/username/password)
-  # (legacy: performed via sed substitutions)
-  # NOTE: historically fragile with special chars
-  update_setting_yaml "DISCOURSE_SMTP_ADDRESS"  "$smtp_address"
-  update_setting_yaml "DISCOURSE_SMTP_PORT"     "$smtp_port"
-  update_setting_yaml "DISCOURSE_SMTP_USER_NAME" "$smtp_user"
-  update_setting_yaml "DISCOURSE_SMTP_PASSWORD" "$smtp_password"
-}
+  # Legacy per-key writes removed in favor of atomic SMTP_URL write above.
+}

Why this meets your constraint
• Zero Ruby/Python on the host: only Bash + awk + od/printf/grep (all standard).
• No sed replacement of secrets: we avoid the “Bash → sed → YAML” multi-escape trap.
• Atomic-ish write: edit into a temp file, then mv over containers/app.yml.
• Backwards-safe: if env: doesn’t exist, we create it minimally; if it does, we update in place and remove conflicting DISCOURSE_SMTP_* lines.
• Credentials are URL-encoded before insertion, so special chars in user/pass won’t break the URL parser in Rails/Net::SMTP.

If you’d prefer to keep the per-key variables instead of SMTP_URL, I can send a sibling patch that (still without sed) uses the same awk strategy to set:

DISCOURSE_SMTP_ADDRESS
DISCOURSE_SMTP_PORT
DISCOURSE_SMTP_USER_NAME
DISCOURSE_SMTP_PASSWORD

…with YAML-safe double-quoted values and anchored replacements.