Description

This repository contains three Apache C++ modules, mod_dup, mod_migrate and mod_compare which duplicate, redirect and compare HTTP requests respectively.

mod_dup

mod_dup duplicates Apache requests (POST, GET or both).
Only requests which match specified filters are duplicated.
Filters can be applied on URL path, query string, headers, and/or body. Substitutions may be applied to duplicated requests.
To minimize resource usage, mod_dup adapts to the amount of incoming requests by adjusting its number of threads.
If maximum thresholds are reached, requests are dropped. In other words, mod_dup is built to guarantee a low system impact by sacrificing the reliability of duplications. However, by using a high number of maximum threads, request dropping can be avoided and system impact raised. mod_dup periodically emits log messages containing metrics such as the number of dropped requests.

mod_compare

mod_compare allows to compare the response header and body of HTTP Requests between two web services. mod_compare receives an http request which contains the response header and body of a Web Service that will be compared to the response of the web service installed in the same server of mod_compare. In order to work fine, the input request must contain the following header:

• Duplication Type: Response and must respect the "dup format":
• URL --> the URL of orifinal request
• BODY --> XXXXXXXX{request_body}XXXXXXXX{response_header}XXXXXXXX{response_body} The first 8 characters indicate the size of the request body. Then the request body, 8 characters for the size of the response header, the response header, 8 characters for the size of the response body and the response body. Two operating modes are possible:
• Response Comparison
• No Comparison

WARNING: The Web Services must not be CGI based scripts.

mod_migrate

mod_migrate allows redirecting requests based on the body content, on top of mod_rewrite which can only match URLs and Headers. Hence all HTTP Methods may be redirected or proxied (GET, POST, PUT, PATCH...). Only requests which match specified filters are migrated. This mod uses mod_rewrite and mod_proxy to redirect the requests.

Basic Request Migration

Basic Request Duplication with Migration

Duplication with Response

Documentation

For usage and configuration documentation, read the module's Wiki at this page https://github.com/Orange-OpenSource/mod_dup/wiki
To generate the technical documentation of the code using doxygen, see documentation in the Build section.

Build

First create and go into a build directory: mkdir build cd build

then run cmake & make: cmake .. make

Unit Tests

Note that for the test "testLibCompare" to pass, you need to use a modified libjsoncpp which preserves json objects key sorting.

build with unit tests:

cmake -DBUILD_UNIT_TESTS=ON ..
make test
CTEST_OUTPUT_ON_FAILURE=1 make test

or with coverage:

cmake -DBUILD_COVERAGE=ON ..
make coverage-unit (or make coverage-functional, make coverage-functional-compare, make coverage-compaign)
CTEST_OUTPUT_ON_FAILURE=1 make test

<browser> measures/coverage/html/index.html

Generate Doxygen Documentation

cmake ..
make doc

<browser> docs/doxygen/html/index.html

Install code and tests

Go to build directory:

sudo make install
sudo service apache2 restart

This installs the code and functional tests to apache2 folders

Functional Tests

Make sure you installed code and tests and restarted apache

make check-functional

Packaging

A debian folder compatible with Ubuntu Precise and Trusty is present
Just run from the repository base folder:

dpkg-buildpackage

Dependencies

Build time

On ubuntu (compatible with Precise 12.04 LTS, Trusty 14.04 LTS, Xenial 16.04 LTS, Bionic 18.04 LTS): sudo apt install
cmake
libcurl4-openssl-dev
libboost-thread-dev
libboost-regex-dev
libboost-dev
libapr1-dev
libaprutil1-dev
apache2-dev

    OR apache2-threaded-dev
    OR apache2-prefork-dev
gcc (>= 4.4.3)

Run time

apache2.2-common
libboost-thread1.40.0
libboost-regex1.40.0
libcurl3