commit map

Contextual Example

This operation can be performed as part of a series of operations used to manage map files. The example in this section demonstrates how to modify mappings in HAProxy Enterprise's running configuration. The mappings are not persisted to the map file on disk. Any changes you make via the Runtime API are lost when the proxy halts.

Assume that you have a map file named /etc/hapee-2.4/routes.map with the following contents where the first column contains the keys and the second contains the values:

/cart/     cart_api
/reviews/  reviews_api

In the HAProxy Enterprise configuration, we reference this map file on a use_backend line with the map_beg fetch method. This tells the load balancer to choose the backend from the map file by matching the beginning of the requested URL path with a key in the file:

frontend fe_main
   bind :80
   use_backend %[path,map_beg(/etc/hapee-2.4/routes.map,be_servers)]

1. Use the show maps command to list map files and their unique IDs. Here, the map file /etc/hapee-2.4/routes.map has an ID of 0:

   $ echo "show map" | \
      sudo socat stdio unix-connect:/var/run/hapee-2.4/hapee-lb.sock

   # id (file) description
   0 (/etc/hapee-2.4/routes.map) pattern loaded from file '/etc/hapee-2.4/routes.map' used by map at file '/etc/hapee-2.4/hapee-lb.cfg' line 61. curr_ver=0 next_ver=1 entry_cnt=0

2. Pass the map file's unique ID to show map to display entries in the file:

   $ echo "show map #0" | \
      sudo socat stdio unix-connect:/var/run/hapee-2.4/hapee-lb.sock

   0x563bbeeee160 /cart/ cart_api
   0x563bbeeee1a0 /reviews/ reviews_api

3. Pass the map file's unique ID to prepare map to start a transaction for map changes. Note the version number, which will be required in later commands. You can display version numbers using the show acl operation.

   $ echo "prepare map #0" | \
      sudo socat stdio unix-connect:/var/run/hapee-2.4/hapee-lb.sock

   New version created: 1

4. Execute the set map command with these arguments: the map's ID, the key to be modified, and a new value to replace the key's existing value.

   Alternatively, use the map file's path instead of its ID.

   In the example below, we modify the /cart/ key, replacing the value cart_api with the value web_servers:

   $ echo "set map #0 /cart/ web_servers" | \
      sudo socat stdio unix-connect:/var/run/hapee-2.4/hapee-lb.sock

5. Call commit map with the version and map ID to commit the change and make it active in runtime memory:

   $ echo "commit map @1 #0" | \
      sudo socat stdio unix-connect:/var/run/hapee-2.4/hapee-lb.sock

6. Call show map to confirm the modification:

   $ echo "show map #0" | \
      sudo socat stdio unix-connect:/var/run/hapee-2.4/hapee-lb.sock

   0x563bbeeee160 /cart/ web_servers
   0x563bbeeee1a0 /reviews/ reviews_api