http-client-overrides
A library for applying overrides to ManagerSettings
when using the http-client Haskell library.
Usage
You probably have some IO do notation hidden somewhere which looks like this:
manager <- newManager tlsManagerSettings
Replace it with this:
settings <- withHttpClientOverridesThrow tlsManagerSettings
manager <- newManager settings
Set the HTTP_CLIENT_OVERRIDES environment variable to the location of your
configuration file. When this environment variable is not set there is no
additional overhead for HTTP requests as the ManagerSettings will not be
modified. Refer to the example directory for a sample Haskell
program and configuration file.
Features
Log HTTP requests and responses
The following fields can be used to print log messages for all HTTP responses,
requests and request overrides:
version: v1
logOptions:
responses: simple
requests: simple
requestOverrides: simple
The currently supported log formats are simple and detailed. Sample output
for the simple log format is shown below:
Overriding request: https://unreachable.domain/ -> https://github.com/
Request: GET https://github.com/ HTTP/1.1
Response: HTTP/1.1 200 OK
Override HTTP requests
Match HTTP requests corresponding to a match URL and transform the request
according to an override URL:
version: v1
requestOverrides:
- match: unreachable.domain
override: github.com
Match semantics
Matches the first HTTP request which:
- has the same scheme, host and port as the match URL
- has a path which is a suffix of the path in the match URL
Any URL segments ommitted from the match URL are not required for matching.
Override semantics
Overrides an HTTP request with:
- the scheme, host and port specified in the override URL
- replaces the prefix of a matched path with the path in the override URL
Any URL segments ommitted from the override URL will not be applied to the HTTP
request.
Examples
Override all HTTP requests on port 80 to use HTTPS on port 443 (note: the port
is never automatically interpreted from the scheme):
version: v1
requestOverrides:
- match: http://:80
override: https://:443
Override all requests to the host github.com which have a path prefix of
/dhall-lang/dhall-lang/ to use a path prefix of
/robbiemcmichael/dhall-lang/ instead.
version: v1
requestOverrides:
- match: https://github.com/dhall-lang/dhall-lang/
override: https://github.com/robbiemcmichael/dhall-lang/
Debugging
Set logOptions.requestOverrides to detailed to see how the URLs have been
parsed and how any matched HTTP requests are being overridden.