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README.md

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+# EOSIO API Healthcheck for HAProxy
+
+This program implements EOSIO healthcheck for HAProxy over TCP.
+
+## TCP Protocol
+
+The protocol is simple and has 4 rules.
+
+1. Data is transmitted in `packets` encoded in ascii and ends with newline `\n`.
+2. There are two types of packages: `Request` and `Response`. Each `Request` has exactly one `Response`.
+3. Each parameter inside a `Request` is separated by `:`
+4. Each response contains exactly one `status code` (see below)
+
+
+### Request
+
+The following parameters are supported in a request and are ordered from
+first to last below:
+
+| # | Name       | Required | Description                                                            |
+| - | ---------- | -------- | ---------------------------------------------------------------------- |
+| 1 | Host       | Yes      | IP/Hostname to the api.                                                |
+| 2 | Port       | No       | Port number to the api (default `80`)                                  |
+| 3 | num_blocks | No       | Number of blocks the api can drift before reported `down` (default 10) |
+| 4 | hyperion   | No       | `1` if hyperion healthcheck should be used (default `0`)               |
+
+### Response
+
+The api can respond with exactly one `status code`.
+See [HAproxy documentation](https://cbonte.github.io/haproxy-dconv/1.7/configuration.html#5.2-agent-check) for more information
+
+| code      | Description                                                |
+| --------- | ---------------------------------------------------------- |
+| `up`      | Api is healthy                                             |
+| `down`    | Api is not healthy                                         |
+| `failed`  | The program failed to read the status from the api.        |
+| `maint`   | Api is set in maintenance mode (not used)                  |
+| `ready`   | Api is ready again after being in `maint` state (not used) |
+| `stopped` | Api has been stopped manually (not used)                   |
+
+## Author
+
+Henrik Hautakoski - [henrik@eossweden.org](mailto:henrik@eossweden.org)