671 lines
32 KiB
Plaintext
671 lines
32 KiB
Plaintext
----------------------
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HAProxy how-to
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----------------------
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version 1.6-dev
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willy tarreau
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2015/08/30
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1) How to build it
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------------------
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First, please note that this version is a development version, so in general if
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you are not used to build from sources or if you don't have the time to track
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very frequent updates, it is recommended that instead you switch to the stable
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version (1.5) or follow the packaged updates provided by your software vendor
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or Linux distribution. Most of them are taking this task seriously and are
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doing a good job. If for any reason you'd prefer a different version than the
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one packaged for your system, or to get some commercial support, other choices
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are available at :
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http://www.haproxy.com/
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To build haproxy, you will need :
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- GNU make. Neither Solaris nor OpenBSD's make work with the GNU Makefile.
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If you get many syntax errors when running "make", you may want to retry
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with "gmake" which is the name commonly used for GNU make on BSD systems.
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- GCC between 2.95 and 4.8. Others may work, but not tested.
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- GNU ld
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Also, you might want to build with libpcre support, which will provide a very
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efficient regex implementation and will also fix some badness on Solaris' one.
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To build haproxy, you have to choose your target OS amongst the following ones
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and assign it to the TARGET variable :
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- linux22 for Linux 2.2
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- linux24 for Linux 2.4 and above (default)
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- linux24e for Linux 2.4 with support for a working epoll (> 0.21)
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- linux26 for Linux 2.6 and above
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- linux2628 for Linux 2.6.28, 3.x, and above (enables splice and tproxy)
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- solaris for Solaris 8 or 10 (others untested)
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- freebsd for FreeBSD 5 to 10 (others untested)
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- osx for Mac OS/X
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- openbsd for OpenBSD 3.1 and above
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- aix51 for AIX 5.1
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- aix52 for AIX 5.2
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- cygwin for Cygwin
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- generic for any other OS or version.
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- custom to manually adjust every setting
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You may also choose your CPU to benefit from some optimizations. This is
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particularly important on UltraSparc machines. For this, you can assign
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one of the following choices to the CPU variable :
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- i686 for intel PentiumPro, Pentium 2 and above, AMD Athlon
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- i586 for intel Pentium, AMD K6, VIA C3.
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- ultrasparc : Sun UltraSparc I/II/III/IV processor
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- native : use the build machine's specific processor optimizations. Use with
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extreme care, and never in virtualized environments (known to break).
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- generic : any other processor or no CPU-specific optimization. (default)
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Alternatively, you may just set the CPU_CFLAGS value to the optimal GCC options
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for your platform.
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You may want to build specific target binaries which do not match your native
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compiler's target. This is particularly true on 64-bit systems when you want
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to build a 32-bit binary. Use the ARCH variable for this purpose. Right now
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it only knows about a few x86 variants (i386,i486,i586,i686,x86_64), two
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generic ones (32,64) and sets -m32/-m64 as well as -march=<arch> accordingly.
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If your system supports PCRE (Perl Compatible Regular Expressions), then you
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really should build with libpcre which is between 2 and 10 times faster than
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other libc implementations. Regex are used for header processing (deletion,
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rewriting, allow, deny). The only inconvenient of libpcre is that it is not
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yet widely spread, so if you build for other systems, you might get into
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trouble if they don't have the dynamic library. In this situation, you should
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statically link libpcre into haproxy so that it will not be necessary to
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install it on target systems. Available build options for PCRE are :
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- USE_PCRE=1 to use libpcre, in whatever form is available on your system
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(shared or static)
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- USE_STATIC_PCRE=1 to use a static version of libpcre even if the dynamic
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one is available. This will enhance portability.
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- with no option, use your OS libc's standard regex implementation (default).
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Warning! group references on Solaris seem broken. Use static-pcre whenever
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possible.
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Recent systems can resolve IPv6 host names using getaddrinfo(). This primitive
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is not present in all libcs and does not work in all of them either. Support in
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glibc was broken before 2.3. Some embedded libs may not properly work either,
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thus, support is disabled by default, meaning that some host names which only
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resolve as IPv6 addresses will not resolve and configs might emit an error
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during parsing. If you know that your OS libc has reliable support for
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getaddrinfo(), you can add USE_GETADDRINFO=1 on the make command line to enable
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it. This is the recommended option for most Linux distro packagers since it's
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working fine on all recent mainstream distros. It is automatically enabled on
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Solaris 8 and above, as it's known to work.
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It is possible to add native support for SSL using the GNU makefile, by passing
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"USE_OPENSSL=1" on the make command line. The libssl and libcrypto will
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automatically be linked with haproxy. Some systems also require libz, so if the
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build fails due to missing symbols such as deflateInit(), then try again with
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"ADDLIB=-lz".
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To link OpenSSL statically against haproxy, build OpenSSL with the no-shared
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keyword and install it to a local directory, so your system is not affected :
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$ export STATICLIBSSL=/tmp/staticlibssl
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$ ./config --prefix=$STATICLIBSSL no-shared
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$ make && make install_sw
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When building haproxy, pass that path via SSL_INC and SSL_LIB to make and
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include additional libs with ADDLIB if needed (in this case for example libdl):
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$ make TARGET=linux26 USE_OPENSSL=1 SSL_INC=$STATICLIBSSL/include SSL_LIB=$STATICLIBSSL/lib ADDLIB=-ldl
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It is also possible to include native support for ZLIB to benefit from HTTP
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compression. For this, pass "USE_ZLIB=1" on the "make" command line and ensure
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that zlib is present on the system. Alternatively it is possible to use libslz
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for a faster, memory less, but slightly less efficient compression, by passing
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"USE_SLZ=1".
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By default, the DEBUG variable is set to '-g' to enable debug symbols. It is
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not wise to disable it on uncommon systems, because it's often the only way to
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get a complete core when you need one. Otherwise, you can set DEBUG to '-s' to
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strip the binary.
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For example, I use this to build for Solaris 8 :
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$ make TARGET=solaris CPU=ultrasparc USE_STATIC_PCRE=1
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And I build it this way on OpenBSD or FreeBSD :
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$ gmake TARGET=freebsd USE_PCRE=1 USE_OPENSSL=1 USE_ZLIB=1
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And on a classic Linux with SSL and ZLIB support (eg: Red Hat 5.x) :
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$ make TARGET=linux26 USE_PCRE=1 USE_OPENSSL=1 USE_ZLIB=1
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And on a recent Linux >= 2.6.28 with SSL and ZLIB support :
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$ make TARGET=linux2628 USE_PCRE=1 USE_OPENSSL=1 USE_ZLIB=1
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In order to build a 32-bit binary on an x86_64 Linux system with SSL support
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without support for compression but when OpenSSL requires ZLIB anyway :
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$ make TARGET=linux26 ARCH=i386 USE_OPENSSL=1 ADDLIB=-lz
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The SSL stack supports session cache synchronization between all running
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processes. This involves some atomic operations and synchronization operations
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which come in multiple flavors depending on the system and architecture :
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Atomic operations :
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- internal assembler versions for x86/x86_64 architectures
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- gcc builtins for other architectures. Some architectures might not
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be fully supported or might require a more recent version of gcc.
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If your architecture is not supported, you willy have to either use
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pthread if supported, or to disable the shared cache.
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- pthread (posix threads). Pthreads are very common but inter-process
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support is not that common, and some older operating systems did not
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report an error when enabling multi-process mode, so they used to
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silently fail, possibly causing crashes. Linux's implementation is
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fine. OpenBSD doesn't support them and doesn't build. FreeBSD 9 builds
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and reports an error at runtime, while certain older versions might
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silently fail. Pthreads are enabled using USE_PTHREAD_PSHARED=1.
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Synchronization operations :
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- internal spinlock : this mode is OS-independant, light but will not
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scale well to many processes. However, accesses to the session cache
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are rare enough that this mode could certainly always be used. This
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is the default mode.
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- Futexes, which are Linux-specific highly scalable light weight mutexes
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implemented in user-space with some limited assistance from the kernel.
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This is the default on Linux 2.6 and above and is enabled by passing
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USE_FUTEX=1
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- pthread (posix threads). See above.
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If none of these mechanisms is supported by your platform, you may need to
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build with USE_PRIVATE_CACHE=1 to totally disable SSL cache sharing. Then
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it is better not to run SSL on multiple processes.
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If you need to pass other defines, includes, libraries, etc... then please
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check the Makefile to see which ones will be available in your case, and
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use the USE_* variables in the Makefile.
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AIX 5.3 is known to work with the generic target. However, for the binary to
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also run on 5.2 or earlier, you need to build with DEFINE="-D_MSGQSUPPORT",
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otherwise __fd_select() will be used while not being present in the libc, but
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this is easily addressed using the "aix52" target. If you get build errors
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because of strange symbols or section mismatches, simply remove -g from
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DEBUG_CFLAGS.
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You can easily define your own target with the GNU Makefile. Unknown targets
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are processed with no default option except USE_POLL=default. So you can very
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well use that property to define your own set of options. USE_POLL can even be
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disabled by setting USE_POLL="". For example :
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$ gmake TARGET=tiny USE_POLL="" TARGET_CFLAGS=-fomit-frame-pointer
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1.1) DeviceAtlas Device Detection
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---------------------------------
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In order to add DeviceAtlas Device Detection support, you would need to download
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the API source code from https://deviceatlas.com/deviceatlas-haproxy-module and
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once extracted :
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$ make TARGET=<target> USE_PCRE=1 USE_DEVICEATLAS=1 DEVICEATLAS_SRC=<path to the API root folder>
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Optionally DEVICEATLAS_INC and DEVICEATLAS_LIB may be set to override the path
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to the include files and libraries respectively if they're not in the source
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directory.
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These are supported DeviceAtlas directives (see doc/configuration.txt) :
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- deviceatlas-json-file <path to the DeviceAtlas JSON data file>.
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- deviceatlas-log-level <number> (0 to 3, level of information returned by
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the API, 0 by default).
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- deviceatlas-property-separator <character> (character used to separate the
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properties produced by the API, | by default).
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Sample configuration :
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global
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deviceatlas-json-file <path to json file>
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...
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frontend
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bind *:8881
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default_backend servers
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http-request set-header X-DeviceAtlas-Data %[req.fhdr(User-Agent),da-csv(primaryHardwareType,osName,osVersion,browserName,browserVersion)]
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1.2) 51Degrees Device Detection
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-------------------------------
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You can also include 51Degrees for inbuilt device detection enabling attributes
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such as screen size (physical & pixels), supported input methods, release date,
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hardware vendor and model, browser information, and device price among many
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others. Such information can be used to improve the user experience of a web
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site by tailoring the page content, layout and business processes to the
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precise characteristics of the device. Such customisations improve profit by
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making it easier for customers to get to the information or services they
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need. Theses attributes of the device making a web request can be added to HTTP
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headers as configurable parameters.
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In order to enable 51Degrees get the 51Degrees source code from the official
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github repository :
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git clone https://github.com/51Degreesmobi/51Degrees-C
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then run 'make' with USE_51DEGREES and 51DEGREES_SRC set. Both 51DEGREES_INC
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and 51DEGREES_LIB may additionally be used to force specific different paths
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for .o and .h, but will default to 51DEGREES_SRC. Make sure to replace
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'51D_REPO_PATH' with the path to the 51Degrees repository.
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51Degrees provide 2 different detection algorithms :
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1. Pattern - balances main memory usage and CPU.
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2. Trie - a very high performance detection solution which uses more main
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memory than Pattern.
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To make with 51Degrees Pattern algorithm use the following command line.
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$ make TARGET=linux26 USE_51DEGREES=1 51DEGREES_SRC='51D_REPO_PATH'/src/pattern
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To use the 51Degrees Trie algorithm use the following command line.
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$ make TARGET=linux26 USE_51DEGREES=1 51DEGREES_SRC='51D_REPO_PATH'/src/trie
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A data file containing information about devices, browsers, operating systems
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and their associated signatures is then needed. 51Degrees provide a free
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database with Github repo for this purpose. These free data files are located
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in '51D_REPO_PATH'/data with the extensions .dat for Pattern data and .trie for
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Trie data.
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The configuration file needs to set the following parameters:
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51degrees-data-file path to the pattern or trie data file
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51degrees-property-name-list list of 51Degrees properties to detect
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51degrees-property-separator separator to use between values
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51degrees-cache-size LRU-based cache size (disabled by default)
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The following is an example of the settings for Pattern.
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51degrees-data-file '51D_REPO_PATH'/data/51Degrees-Lite.dat
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51degrees-property-name-list IsTablet DeviceType IsMobile
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51degrees-property-separator ,
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51degrees-cache-size 10000
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HAProxy needs a way to pass device information to the backend servers. This is
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done by using the 51d converter, which intercepts the User-Agent header and
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creates some new headers. This is controlled in the frontend http-in section
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The following is an example which adds two new HTTP headers prefixed X-51D-
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frontend http-in
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bind *:8081
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default_backend servers
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http-request set-header X-51D-DeviceTypeMobileTablet %[req.fhdr(User-Agent),51d(DeviceType,IsMobile,IsTablet)]
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http-request set-header X-51D-Tablet %[req.fhdr(User-Agent),51d(IsTablet)]
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Here, two headers are created with 51Degrees data, X-51D-DeviceTypeMobileTablet
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and X-51D-Tablet. Any number of headers can be created this way and can be
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named anything. The User-Agent header is passed to the converter in
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req.fhdr(User-Agent). 51d( ) invokes the 51degrees converter. It can be passed
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up to five property names of values to return. Values will be returned in the
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same order, seperated by the 51-degrees-property-separator configured earlier.
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If a property name can't be found the value 'NoData' is returned instead.
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The free Lite data file contains information about screen size in pixels and
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whether the device is a mobile. A full list of available properties is located
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on the 51Degrees web site at:
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https://51degrees.com/resources/property-dictionary.
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Some properties are only available in the paid for Premium and Enterprise
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versions of 51Degrees. These data sets no only contain more properties but
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are updated weekly and daily and contain signatures for 100,000s of different
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device combinations. For more information see the data options comparison web
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page:
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https://51degrees.com/compare-data-options
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2) How to install it
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--------------------
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To install haproxy, you can either copy the single resulting binary to the
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place you want, or run :
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$ sudo make install
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If you're packaging it for another system, you can specify its root directory
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in the usual DESTDIR variable.
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3) How to set it up
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-------------------
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There is some documentation in the doc/ directory :
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- intro.txt : this is an introduction to haproxy, it explains what it is
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what it is not. Useful for beginners or to re-discover it when planning
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for an upgrade.
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- architecture.txt : this is the architecture manual. It is quite old and
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does not tell about the nice new features, but it's still a good starting
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point when you know what you want but don't know how to do it.
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- configuration.txt : this is the configuration manual. It recalls a few
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essential HTTP basic concepts, and details all the configuration file
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syntax (keywords, units). It also describes the log and stats format. It
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is normally always up to date. If you see that something is missing from
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it, please report it as this is a bug. Please note that this file is
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huge and that it's generally more convenient to review Cyril Bont<6E>'s
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HTML translation online here :
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http://cbonte.github.io/haproxy-dconv/configuration-1.5.html
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- haproxy-en.txt / haproxy-fr.txt : these are the old outdated docs. You
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should never need them. If you do, then please report what you didn't
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find in the other ones.
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- gpl.txt / lgpl.txt : the copy of the licenses covering the software. See
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the 'LICENSE' file at the top for more information.
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- the rest is mainly for developers.
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There are also a number of nice configuration examples in the "examples"
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directory as well as on several sites and articles on the net which are linked
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to from the haproxy web site.
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4) How to report a bug
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----------------------
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It is possible that from time to time you'll find a bug. A bug is a case where
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what you see is not what is documented. Otherwise it can be a misdesign. If you
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find that something is stupidly design, please discuss it on the list (see the
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"how to contribute" section below). If you feel like you're proceeding right
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and haproxy doesn't obey, then first ask yourself if it is possible that nobody
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before you has even encountered this issue. If it's unlikely, the you probably
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have an issue in your setup. Just in case of doubt, please consult the mailing
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list archives :
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http://marc.info/?l=haproxy
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Otherwise, please try to gather the maximum amount of information to help
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reproduce the issue and send that to the mailing list :
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haproxy@formilux.org
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Please include your configuration and logs. You can mask your IP addresses and
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passwords, we don't need them. But it's essential that you post your config if
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you want people to guess what is happening.
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Also, keep in mind that haproxy is designed to NEVER CRASH. If you see it die
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without any reason, then it definitely is a critical bug that must be reported
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and urgently fixed. It has happened a couple of times in the past, essentially
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on development versions running on new architectures. If you think your setup
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is fairly common, then it is possible that the issue is totally unrelated.
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Anyway, if that happens, feel free to contact me directly, as I will give you
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instructions on how to collect a usable core file, and will probably ask for
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other captures that you'll not want to share with the list.
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5) How to contribute
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--------------------
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It is possible that you'll want to add a specific feature to satisfy your needs
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or one of your customers'. Contributions are welcome, however I'm often very
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picky about changes. I will generally reject patches that change massive parts
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of the code, or that touch the core parts without any good reason if those
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changes have not been discussed first.
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The proper place to discuss your changes is the HAProxy Mailing List. There are
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enough skilled readers to catch hazardous mistakes and to suggest improvements.
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I trust a number of them enough to merge a patch if they say it's OK, so using
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the list is the fastest way to get your code reviewed and merged. You can
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subscribe to it by sending an empty e-mail at the following address :
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haproxy+subscribe@formilux.org
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If you have an idea about something to implement, *please* discuss it on the
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list first. It has already happened several times that two persons did the same
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thing simultaneously. This is a waste of time for both of them. It's also very
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common to see some changes rejected because they're done in a way that will
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conflict with future evolutions, or that does not leave a good feeling. It's
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always unpleasant for the person who did the work, and it is unpleasant for me
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too because I value people's time and efforts. That would not happen if these
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were discussed first. There is no problem posting work in progress to the list,
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it happens quite often in fact. Also, don't waste your time with the doc when
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submitting patches for review, only add the doc with the patch you consider
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ready to merge.
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Another important point concerns code portability. Haproxy requires gcc as the
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C compiler, and may or may not work with other compilers. However it's known
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to build using gcc 2.95 or any later version. As such, it is important to keep
|
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in mind that certain facilities offered by recent versions must not be used in
|
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the code :
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- declarations mixed in the code (requires gcc >= 3.x)
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- GCC builtins without checking for their availability based on version and
|
||
architecture ;
|
||
- assembly code without any alternate portable form for other platforms
|
||
- use of stdbool.h, "bool", "false", "true" : simply use "int", "0", "1"
|
||
- in general, anything which requires C99 (such as declaring variables in
|
||
"for" statements)
|
||
|
||
Since most of these restrictions are just a matter of coding style, it is
|
||
normally not a problem to comply.
|
||
|
||
If your work is very confidential and you can't publicly discuss it, you can
|
||
also mail me directly about it, but your mail may be waiting several days in
|
||
the queue before you get a response.
|
||
|
||
If you'd like a feature to be added but you think you don't have the skills to
|
||
implement it yourself, you should follow these steps :
|
||
|
||
1. discuss the feature on the mailing list. It is possible that someone
|
||
else has already implemented it, or that someone will tell you how to
|
||
proceed without it, or even why not to do it. It is also possible that
|
||
in fact it's quite easy to implement and people will guide you through
|
||
the process. That way you'll finally have YOUR patch merged, providing
|
||
the feature YOU need.
|
||
|
||
2. if you really can't code it yourself after discussing it, then you may
|
||
consider contacting someone to do the job for you. Some people on the
|
||
list might sometimes be OK with trying to do it.
|
||
|
||
Note to contributors: it's very handy when patches comes with a properly
|
||
formated subject. There are 3 criteria of particular importance in any patch :
|
||
|
||
- its nature (is it a fix for a bug, a new feature, an optimization, ...)
|
||
- its importance, which generally reflects the risk of merging/not merging it
|
||
- what area it applies to (eg: http, stats, startup, config, doc, ...)
|
||
|
||
It's important to make these 3 criteria easy to spot in the patch's subject,
|
||
because it's the first (and sometimes the only) thing which is read when
|
||
reviewing patches to find which ones need to be backported to older versions.
|
||
|
||
Specifically, bugs must be clearly easy to spot so that they're never missed.
|
||
Any patch fixing a bug must have the "BUG" tag in its subject. Most common
|
||
patch types include :
|
||
|
||
- BUG fix for a bug. The severity of the bug should also be indicated
|
||
when known. Similarly, if a backport is needed to older versions,
|
||
it should be indicated on the last line of the commit message. If
|
||
the bug has been identified as a regression brought by a specific
|
||
patch or version, this indication will be appreciated too. New
|
||
maintenance releases are generally emitted when a few of these
|
||
patches are merged.
|
||
|
||
- CLEANUP code cleanup, silence of warnings, etc... theorically no impact.
|
||
These patches will rarely be seen in stable branches, though they
|
||
may appear when they remove some annoyance or when they make
|
||
backporting easier. By nature, a cleanup is always minor.
|
||
|
||
- REORG code reorganization. Some blocks may be moved to other places,
|
||
some important checks might be swapped, etc... These changes
|
||
always present a risk of regression. For this reason, they should
|
||
never be mixed with any bug fix nor functional change. Code is
|
||
only moved as-is. Indicating the risk of breakage is highly
|
||
recommended.
|
||
|
||
- BUILD updates or fixes for build issues. Changes to makefiles also fall
|
||
into this category. The risk of breakage should be indicated if
|
||
known. It is also appreciated to indicate what platforms and/or
|
||
configurations were tested after the change.
|
||
|
||
- OPTIM some code was optimised. Sometimes if the regression risk is very
|
||
low and the gains significant, such patches may be merged in the
|
||
stable branch. Depending on the amount of code changed or replaced
|
||
and the level of trust the author has in the change, the risk of
|
||
regression should be indicated.
|
||
|
||
- RELEASE release of a new version (development or stable).
|
||
|
||
- LICENSE licensing updates (may impact distro packagers).
|
||
|
||
|
||
When the patch cannot be categorized, it's best not to put any tag. This is
|
||
commonly the case for new features, which development versions are mostly made
|
||
of.
|
||
|
||
Additionally, the importance of the patch should be indicated when known. A
|
||
single upper-case word is preferred, among :
|
||
|
||
- MINOR minor change, very low risk of impact. It is often the case for
|
||
code additions that don't touch live code. For a bug, it generally
|
||
indicates an annoyance, nothing more.
|
||
|
||
- MEDIUM medium risk, may cause unexpected regressions of low importance or
|
||
which may quickly be discovered. For a bug, it generally indicates
|
||
something odd which requires changing the configuration in an
|
||
undesired way to work around the issue.
|
||
|
||
- MAJOR major risk of hidden regression. This happens when I rearrange
|
||
large parts of code, when I play with timeouts, with variable
|
||
initializations, etc... We should only exceptionally find such
|
||
patches in stable branches. For a bug, it indicates severe
|
||
reliability issues for which workarounds are identified with or
|
||
without performance impacts.
|
||
|
||
- CRITICAL medium-term reliability or security is at risk and workarounds,
|
||
if they exist, might not always be acceptable. An upgrade is
|
||
absolutely required. A maintenance release may be emitted even if
|
||
only one of these bugs are fixed. Note that this tag is only used
|
||
with bugs. Such patches must indicate what is the first version
|
||
affected, and if known, the commit ID which introduced the issue.
|
||
|
||
If this criterion doesn't apply, it's best not to put it. For instance, most
|
||
doc updates and most examples or test files are just added or updated without
|
||
any need to qualify a level of importance.
|
||
|
||
The area the patch applies to is quite important, because some areas are known
|
||
to be similar in older versions, suggesting a backport might be desirable, and
|
||
conversely, some areas are known to be specific to one version. When the tag is
|
||
used alone, uppercase is preferred for readability, otherwise lowercase is fine
|
||
too. The following tags are suggested but not limitative :
|
||
|
||
- doc documentation updates or fixes. No code is affected, no need to
|
||
upgrade. These patches can also be sent right after a new feature,
|
||
to document it.
|
||
|
||
- examples example files. Be careful, sometimes these files are packaged.
|
||
|
||
- tests regression test files. No code is affected, no need to upgrade.
|
||
|
||
- init initialization code, arguments parsing, etc...
|
||
|
||
- config configuration parser, mostly used when adding new config keywords
|
||
|
||
- http the HTTP engine
|
||
|
||
- stats the stats reporting engine as well as the stats socket CLI
|
||
|
||
- checks the health checks engine (eg: when adding new checks)
|
||
|
||
- acl the ACL processing core or some ACLs from other areas
|
||
|
||
- peers the peer synchronization engine
|
||
|
||
- listeners everything related to incoming connection settings
|
||
|
||
- frontend everything related to incoming connection processing
|
||
|
||
- backend everything related to LB algorithms and server farm
|
||
|
||
- session session processing and flags (very sensible, be careful)
|
||
|
||
- server server connection management, queueing
|
||
|
||
- proxy proxy maintenance (start/stop)
|
||
|
||
- log log management
|
||
|
||
- poll any of the pollers
|
||
|
||
- halog the halog sub-component in the contrib directory
|
||
|
||
- contrib any addition to the contrib directory
|
||
|
||
Other names may be invented when more precise indications are meaningful, for
|
||
instance : "cookie" which indicates cookie processing in the HTTP core. Last,
|
||
indicating the name of the affected file is also a good way to quickly spot
|
||
changes. Many commits were already tagged with "stream_sock" or "cfgparse" for
|
||
instance.
|
||
|
||
It is desired that AT LEAST one of the 3 criteria tags is reported in the patch
|
||
subject. Ideally, we would have the 3 most often. The two first criteria should
|
||
be present before a first colon (':'). If both are present, then they should be
|
||
delimited with a slash ('/'). The 3rd criterion (area) should appear next, also
|
||
followed by a colon. Thus, all of the following messages are valid :
|
||
|
||
Examples of messages :
|
||
- DOC: document options forwardfor to logasap
|
||
- DOC/MAJOR: reorganize the whole document and change indenting
|
||
- BUG: stats: connection reset counters must be plain ascii, not HTML
|
||
- BUG/MINOR: stats: connection reset counters must be plain ascii, not HTML
|
||
- MEDIUM: checks: support multi-packet health check responses
|
||
- RELEASE: Released version 1.4.2
|
||
- BUILD: stats: stdint is not present on solaris
|
||
- OPTIM/MINOR: halog: make fgets parse more bytes by blocks
|
||
- REORG/MEDIUM: move syscall redefinition to specific places
|
||
|
||
Please do not use square brackets anymore around the tags, because they give me
|
||
more work when merging patches. By default I'm asking Git to keep them but this
|
||
causes trouble when patches are prefixed with the [PATCH] tag because in order
|
||
not to store it, I have to hand-edit the patches. So as of now, I will ask Git
|
||
to remove whatever is located between square brackets, which implies that any
|
||
subject formatted the old way will have its tag stripped out.
|
||
|
||
In fact, one of the only square bracket tags that still makes sense is '[RFC]'
|
||
at the beginning of the subject, when you're asking for someone to review your
|
||
change before getting it merged. If the patch is OK to be merged, then I can
|
||
merge it as-is and the '[RFC]' tag will automatically be removed. If you don't
|
||
want it to be merged at all, you can simply state it in the message, or use an
|
||
alternate '[WIP]' tag ("work in progress").
|
||
|
||
The tags are not rigid, follow your intuition first, anyway I reserve the right
|
||
to change them when merging the patch. It may happen that a same patch has a
|
||
different tag in two distinct branches. The reason is that a bug in one branch
|
||
may just be a cleanup in the other one because the code cannot be triggered.
|
||
|
||
|
||
For a more efficient interaction between the mainline code and your code, I can
|
||
only strongly encourage you to try the Git version control system :
|
||
|
||
http://git-scm.com/
|
||
|
||
It's very fast, lightweight and lets you undo/redo your work as often as you
|
||
want, without making your mistakes visible to the rest of the world. It will
|
||
definitely help you contribute quality code and take other people's feedback
|
||
in consideration. In order to clone the HAProxy Git repository :
|
||
|
||
$ git clone http://git.haproxy.org/git/haproxy-1.5.git (stable 1.5)
|
||
$ git clone http://git.haproxy.org/git/haproxy.git/ (development)
|
||
|
||
If you decide to use Git for your developments, then your commit messages will
|
||
have the subject line in the format described above, then the whole description
|
||
of your work (mainly why you did it) will be in the body. You can directly send
|
||
your commits to the mailing list, the format is convenient to read and process.
|
||
|
||
-- end
|