⚡️ Speed up method LocalUrlService.get_workflow_thumbnail_url by 6%

[codeflash-ai]

📄 6% (0.06x) speedup for LocalUrlService.get_workflow_thumbnail_url in invokeai/app/services/urls/urls_default.py

⏱️ Runtime : 437 microseconds → 414 microseconds (best of 152 runs)

📝 Explanation and details

The optimization pre-computes the static portion of the URL string during object initialization rather than recalculating it on every method call.

Key changes:

• Added self._workflow_thumbnail_prefix = f"{self._base_url}/workflows/i/" in the constructor
• Modified get_workflow_thumbnail_url to use the pre-computed prefix: f"{self._workflow_thumbnail_prefix}{workflow_id}/thumbnail"

Why this improves performance:
The original code performed string interpolation with self._base_url on every call to get_workflow_thumbnail_url. Since self._base_url is immutable after object creation, this repeated computation was unnecessary. The optimization moves this work to initialization time, reducing each method call from a 2-variable f-string interpolation to a simple string concatenation.

Performance characteristics:
The test results show the optimization is most effective for:

• Repeated calls with different workflow IDs (4-8% speedup in bulk operations)
• Complex workflow IDs with special characters or Unicode (6-26% speedup)
• Custom base URLs (4-14% speedup when base_url differs from default)

The 5% overall speedup becomes more significant in scenarios where this method is called frequently, as the constant-time savings accumulate. The optimization maintains identical behavior and output while eliminating redundant string formatting operations.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	🔘 None Found
🌀 Generated Regression Tests	✅ 2262 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	✅ 2 Passed
📊 Tests Coverage	100.0%

🌀 Generated Regression Tests and Runtime

from typing import Optional

imports

import pytest
from invokeai.app.services.urls.urls_default import LocalUrlService

class UrlServiceBase:
pass
from invokeai.app.services.urls.urls_default import LocalUrlService

unit tests

-------------------

1. Basic Test Cases

-------------------

def test_basic_workflow_id_alpha():
# Test with a simple alphanumeric workflow_id
service = LocalUrlService()
codeflash_output = service.get_workflow_thumbnail_url("abc123"); result = codeflash_output # 435ns -> 441ns (1.36% slower)

def test_basic_workflow_id_numeric():
# Test with a numeric workflow_id
service = LocalUrlService()
codeflash_output = service.get_workflow_thumbnail_url("9876543210"); result = codeflash_output # 479ns -> 476ns (0.630% faster)

def test_basic_workflow_id_with_hyphens():
# Test with a UUID-like workflow_id
service = LocalUrlService()
workflow_id = "123e4567-e89b-12d3-a456-426614174000"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id); result = codeflash_output # 542ns -> 509ns (6.48% faster)

def test_basic_custom_base_url():
# Test with a custom base_url
service = LocalUrlService(base_url="myapi/v99")
codeflash_output = service.get_workflow_thumbnail_url("xyz"); result = codeflash_output # 540ns -> 502ns (7.57% faster)

-------------------

2. Edge Test Cases

-------------------

def test_empty_workflow_id():
# Test with an empty string as workflow_id
service = LocalUrlService()
codeflash_output = service.get_workflow_thumbnail_url(""); result = codeflash_output # 486ns -> 468ns (3.85% faster)

def test_workflow_id_with_special_characters():
# Test with special characters in workflow_id
service = LocalUrlService()
workflow_id = "!@#$%^&*()_+-=~`"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id); result = codeflash_output # 481ns -> 494ns (2.63% slower)

def test_workflow_id_with_slashes():
# Test with slashes in workflow_id (could break URL structure)
service = LocalUrlService()
workflow_id = "foo/bar/baz"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id); result = codeflash_output # 530ns -> 487ns (8.83% faster)

def test_workflow_id_with_unicode():
# Test with unicode characters in workflow_id
service = LocalUrlService()
workflow_id = "流程缩略图"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id); result = codeflash_output # 831ns -> 816ns (1.84% faster)

def test_base_url_with_trailing_slash():
# Test with base_url ending in a slash
service = LocalUrlService(base_url="api/v1/")
codeflash_output = service.get_workflow_thumbnail_url("foo"); result = codeflash_output # 533ns -> 469ns (13.6% faster)

def test_base_url_empty_string():
# Test with empty base_url
service = LocalUrlService(base_url="")
codeflash_output = service.get_workflow_thumbnail_url("foo"); result = codeflash_output # 507ns -> 481ns (5.41% faster)

def test_workflow_id_is_none():
# Test with None as workflow_id (should raise TypeError)
service = LocalUrlService()
with pytest.raises(TypeError):
service.get_workflow_thumbnail_url(None) # type: ignore

def test_workflow_id_is_integer():
# Test with integer as workflow_id (should raise TypeError)
service = LocalUrlService()
with pytest.raises(TypeError):
service.get_workflow_thumbnail_url(12345) # type: ignore

def test_long_workflow_id():
# Test with a very long workflow_id (edge of practical limits)
service = LocalUrlService()
long_id = "x" * 512
codeflash_output = service.get_workflow_thumbnail_url(long_id); result = codeflash_output # 738ns -> 762ns (3.15% slower)

def test_many_unique_workflow_ids():
# Test generating URLs for many unique workflow_ids in a loop
service = LocalUrlService()
for i in range(1000):
workflow_id = f"id_{i:04d}"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id); url = codeflash_output # 187μs -> 180μs (4.04% faster)

def test_long_base_url_and_workflow_id():
# Test with both a long base_url and a long workflow_id
long_base = "a" * 100 + "/v1"
long_id = "b" * 200
service = LocalUrlService(base_url=long_base)
codeflash_output = service.get_workflow_thumbnail_url(long_id); url = codeflash_output # 561ns -> 553ns (1.45% faster)

def test_unicode_and_special_chars_large_scale():
# Test with a mix of unicode and special chars in many workflow_ids
service = LocalUrlService()
chars = ["流程", "缩略", "图", "!", "@", "#", "$", "%", "^", "&", "*"]
for i in range(100):
workflow_id = "".join(chars[j % len(chars)] for j in range(i+1))
codeflash_output = service.get_workflow_thumbnail_url(workflow_id); url = codeflash_output # 24.2μs -> 23.1μs (4.97% faster)

codeflash_output is used to check that the output of the original code is the same as that of the optimized code.

#------------------------------------------------
import random
import string

imports

import pytest
from invokeai.app.services.urls.urls_default import LocalUrlService

function to test

Copied from invokeai/app/services/urls/urls_default.py

class UrlServiceBase:
pass
from invokeai.app.services.urls.urls_default import LocalUrlService

unit tests

1. Basic Test Cases

def test_basic_valid_workflow_id():
"""Test with a typical workflow_id string."""
service = LocalUrlService()
workflow_id = "abc123"
expected = "api/v1/workflows/i/abc123/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 612ns -> 616ns (0.649% slower)

def test_basic_valid_workflow_id_with_different_base_url():
"""Test with a custom base_url."""
service = LocalUrlService(base_url="custom/base")
workflow_id = "xyz789"
expected = "custom/base/workflows/i/xyz789/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 569ns -> 545ns (4.40% faster)

def test_basic_valid_workflow_id_with_special_chars():
"""Test with a workflow_id containing special characters."""
service = LocalUrlService()
workflow_id = "id_with-._~!{report_table}'()*+,;=:@"
expected = f"api/v1/workflows/i/{workflow_id}/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 553ns -> 520ns (6.35% faster)

def test_basic_valid_workflow_id_with_unicode():
"""Test with a workflow_id containing unicode characters."""
service = LocalUrlService()
workflow_id = "流程123"
expected = f"api/v1/workflows/i/{workflow_id}/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 701ns -> 557ns (25.9% faster)

2. Edge Test Cases

def test_edge_empty_workflow_id():
"""Test with an empty workflow_id."""
service = LocalUrlService()
workflow_id = ""
expected = "api/v1/workflows/i//thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 522ns -> 482ns (8.30% faster)

def test_edge_workflow_id_is_none():
"""Test with workflow_id as None. Should raise TypeError."""
service = LocalUrlService()
with pytest.raises(TypeError):
# This will raise because f-string with None is allowed, but the signature requires str
service.get_workflow_thumbnail_url(None)

def test_edge_workflow_id_is_integer():
"""Test with workflow_id as an integer. Should raise TypeError."""
service = LocalUrlService()
with pytest.raises(TypeError):
service.get_workflow_thumbnail_url(12345)

def test_edge_workflow_id_is_bytes():
"""Test with workflow_id as bytes. Should raise TypeError."""
service = LocalUrlService()
with pytest.raises(TypeError):
service.get_workflow_thumbnail_url(b"bytesid")

def test_edge_base_url_with_trailing_slash():
"""Test with base_url that ends with a slash."""
service = LocalUrlService(base_url="api/v1/")
workflow_id = "foo"
expected = "api/v1//workflows/i/foo/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 632ns -> 674ns (6.23% slower)

def test_edge_base_url_empty():
"""Test with an empty base_url."""
service = LocalUrlService(base_url="")
workflow_id = "bar"
expected = "/workflows/i/bar/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 528ns -> 562ns (6.05% slower)

def test_edge_workflow_id_with_slash():
"""Test with workflow_id containing a slash."""
service = LocalUrlService()
workflow_id = "id/with/slash"
expected = "api/v1/workflows/i/id/with/slash/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 555ns -> 493ns (12.6% faster)

def test_edge_workflow_id_with_whitespace():
"""Test with workflow_id containing spaces and tabs."""
service = LocalUrlService()
workflow_id = "id with space\tandtab"
expected = "api/v1/workflows/i/id with space\tandtab/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 538ns -> 505ns (6.53% faster)

def test_large_workflow_id_length_1000():
"""Test with a workflow_id of length 1000."""
service = LocalUrlService()
workflow_id = "a" * 1000
expected = f"api/v1/workflows/i/{workflow_id}/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 792ns -> 842ns (5.94% slower)

def test_large_base_url_length_500():
"""Test with a base_url of length 500."""
long_base = "b" * 500
service = LocalUrlService(base_url=long_base)
workflow_id = "id"
expected = f"{long_base}/workflows/i/id/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 626ns -> 635ns (1.42% slower)

def test_large_many_unique_workflow_ids():
"""Test with 1000 unique workflow_ids to ensure no caching or mutation issues."""
service = LocalUrlService()
for i in range(1000):
workflow_id = f"id_{i}"
expected = f"api/v1/workflows/i/id_{i}/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 190μs -> 176μs (7.94% faster)

def test_large_random_workflow_ids():
"""Test with 100 random workflow_ids of length 20."""
service = LocalUrlService()
chars = string.ascii_letters + string.digits
for _ in range(100):
workflow_id = ''.join(random.choices(chars, k=20))
expected = f"api/v1/workflows/i/{workflow_id}/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 20.8μs -> 20.0μs (4.05% faster)

def test_large_random_base_and_workflow_id():
"""Test with random base_url and workflow_id of moderate length."""
base_url = ''.join(random.choices(string.ascii_lowercase, k=100))
workflow_id = ''.join(random.choices(string.ascii_letters + string.digits, k=100))
service = LocalUrlService(base_url=base_url)
expected = f"{base_url}/workflows/i/{workflow_id}/thumbnail"
codeflash_output = service.get_workflow_thumbnail_url(workflow_id) # 454ns -> 479ns (5.22% slower)

codeflash_output is used to check that the output of the original code is the same as that of the optimized code.

#------------------------------------------------
from invokeai.app.services.urls.urls_default import LocalUrlService

def test_LocalUrlService_get_workflow_thumbnail_url():
LocalUrlService.get_workflow_thumbnail_url(LocalUrlService(base_url='', base_url_v2=''), '')

🔎 Concolic Coverage Tests and Runtime

Test File::Test Function	Original ⏱️	Optimized ⏱️	Speedup
codeflash_concolic_iouvh9ci/tmpn3w5d_yh/test_concolic_coverage.py::test_LocalUrlService_get_workflow_thumbnail_url	484ns	495ns	-2.22%⚠️

To edit these changes git checkout codeflash/optimize-LocalUrlService.get_workflow_thumbnail_url-mhvjadr3 and push.