Experiencing "Error: JSON schema not found at file://"

[danielbachhuber]

When updating our dependencies from 5.2.1 to 5.2.2 today, we experienced this error:

Error: JSON schema not found at file://

Ref wp-cli/wp-cli#4393 and https://travis-ci.org/wp-cli/wp-cli/jobs/282809129

Let me know what situational details I can provide to help reproduce it. justinrainbow/json-schema is a dependency of Composer, which we use within our application.

[erayd]

Thanks for the heads-up. Could you please let me know the URI of the schema that's triggering the error, and how that schema is loaded? Also, does that schema contain an id, and / or any relative $ref?

[danielbachhuber]

Could you please let me know the URI of the schema that's triggering the error, and how that schema is loaded? Also, does that schema contain an id, and / or any relative $ref?

I'm not entirely sure, but this looks like it could be it: https://github.com/composer/composer/blob/af519de0de087acb11450c2c10225377c8a909ff/res/composer-repository-schema.json

From https://github.com/composer/composer/search?utf8=%E2%9C%93&q=json-schema&type=

I also see https://github.com/composer/composer/blob/e12e0335a4d467878093fc76e3dea592ff3e1ce3/src/Composer/Json/JsonFile.php#L150

[erayd]

@danielbachhuber

I'm having difficulty reproducing this. I've done the following:

1. clone wp-cli/wp-cli locally into /tmp/wp-cli
2. Run composer install
3. Update justinrainbow/json-schema to 5.2.2
4. Inside /tmp/wp-cli, run ./bin/wp package install danielbachhuber/wp-cli-reset-post-date-command

Step 4 (i.e. the first failing travis test) seems to work perfectly without error, as do the other failing tests.

Are you able to provide a minimal test case, or instructions to reproduce?

[erayd]

steve@neith /tmp/wp-cli $ ./bin/wp package install danielbachhuber/wp-cli-reset-post-date-command
Installing package danielbachhuber/wp-cli-reset-post-date-command (dev-master)
Updating /home/steve/.wp-cli/packages/composer.json to require the package...
Using Composer to install the package...
---
Loading composer repositories with package information
Updating dependencies
Resolving dependencies through SAT
Dependency resolution completed in 0.001 seconds
Analyzed 441 packages to resolve dependencies
Analyzed 50 rules to resolve dependencies
Package operations: 1 install, 0 updates, 0 removals
Installs: danielbachhuber/wp-cli-reset-post-date-command:dev-master b8fee09
 - Installing danielbachhuber/wp-cli-reset-post-date-command (dev-master b8fee09)
Writing lock file
Generating autoload files
---
Success: Package installed.

[danielbachhuber]

I've triggered a build to reproduce: wp-cli/wp-cli#4396

[danielbachhuber]

I suspect I know what the issue is (now that I've managed to compare 5.2.1 and 5.2.2).

WP-CLI is built and distributed as a Phar archive. As such, prepending file:// to a path is erroneous because the file protocol inside a Phar is phar://.

I don't know enough about the json-schema codebase to offer an alternative at this point :/

[erayd]

@danielbachhuber It shouldn't be prepending file:// to anything unless there's no protocol provided at all. If phar:// is present in the base URI, then it will be left alone and relative URI will also be resolved as phar://.

I'll investigate to see if there's a possibility that something might be coming through from a phar archive that does not have a phar:// URI prefix on the base, as that would certainly trigger the issue.

[erayd]

I think it's caused by this. Nonsensical behavior, and apparently not a bug (although noting that phar archives are supposed to be filesystem-equivalent it sure seems like a bug to me). I'll refactor this code to avoid the use of realpath().

[erayd]

@danielbachhuber This is fixed in #455.

[danielbachhuber]

👌 Thanks for your help with this, @erayd

[erayd]

No problem. Thanks for reporting the issue :-).

I'll update this issue once the fix is merged (@bighappyface needs to do that part). It'll go to 6.0.0-dev first, then backported for v5.2.5.