Fix: double-encode slashes in prompt template and workflow path segments

[getpancake]

Problem

Prompt template names (and workflow names) that contain / — e.g. feature1/resolve_problem_2 — cause 404 errors because the URL is built as:

/prompt-templates/feature1/resolve_problem_2

The proxy/router sees two path segments after /prompt-templates/, so the request never reaches the handler for a single :promptName segment.

Root cause

A plain encodeURIComponent call does not encode /; the slash passes through literally and splits the URL path.

Fix

Double-encode / characters by applying encodeURIComponent(value).replace(/%2F/gi, "%252F"). This way:

1. After one proxy decode pass, the server receives %2F (still a single path segment).
2. Flask (or the destination framework) then decodes %2F → / inside the named path variable, restoring the original name.

A small encodePathSegment helper was extracted at the top of utils.ts and used in both affected call sites:

• getPromptTemplate — prompt-templates/:name endpoint
• workflow run — workflows/:name/run endpoint

Tests

Added src/utils/utils.test.ts with:

• Unit tests for encodePathSegment (slashes, multiple slashes, no-op for clean names, spaces, lone slash)
• Mock-based integration tests that verify the fetch URL contains %252F when a slash is in the prompt name

All 110 tests pass (npx vitest run).

Related

• Mirrors the Python SDK fix: Fix slash handling in prompt template path segments prompt-layer-library#320
• Original issue: Client fails to fetch prompts with names containing slash prompt-layer-library#254