[Synthetics]: fix lightweight http configuration (#4551)

(cherry picked from commit c74b4a7)

# Conflicts:
#	docs/en/serverless/transclusion/synthetics/reference/lightweight-config/http.asciidoc

docs/en/observability/synthetics-reference/lightweight-config/http.asciidoc

@@ -4,8 +4,8 @@
 |===
 | Option (type) | Description
 
-// hosts
-| [[monitor-http-hosts]] *`hosts`*
+// urls
+| [[monitor-http-urls]] *`urls`*
 (<<synthetics-lightweight-data-string,string>>)
 a| *Required*. The URL to ping.
 
@@ -70,7 +70,7 @@ a| The TLS/SSL connection settings for use with the HTTPS endpoint. If you don't
 - type: http
   id: my-http-service
   name: My HTTP Service
-  hosts: "https://myhost:443"
+  urls: "https://myhost:443"
   schedule: '@every 5s'
   ssl:
     certificate_authorities: ['/etc/ca.crt']

docs/en/serverless/transclusion/synthetics/reference/lightweight-config/http.asciidoc

@@ -0,0 +1,201 @@
+|===
+| Option (type) | Description
+
+| [[monitor-http-urls]]**`urls`**
+(<<synthetics-lightweight-data-string,string>>)
+| **Required**. The URL to ping.
+
+| [[monitor-http-max_redirects]]**`max_redirects`**
+(<<synthetics-lightweight-data-numbers,number>>)
+a| The total number of redirections Synthetics will follow.
+
+By default, Synthetics will not follow redirects, but will report the status of the redirect. If set to a number greater than `0`, Synthetics will follow that number of redirects.
+
+When this option is set to a value greater than `0`, the `monitor.ip` field will no longer be reported, as multiple DNS requests across multiple IPs may return multiple IPs. Fine-grained network timing data will also not be recorded, as with redirects that data will span multiple requests. Specifically the fields `http.rtt.content.us`, `http.rtt.response_header.us`, `http.rtt.total.us`, `http.rtt.validate.us`, `http.rtt.write_request.us` and `dns.rtt.us` will be omitted.
+
+**Default**: `0`
+
+| [[monitor-http-proxy_headers]]**`proxy_headers`**
+| Additional headers to send to proxies during `CONNECT` requests.
+
+| [[monitor-http-proxy_url]]**`proxy_url`**
+(<<synthetics-lightweight-data-string,string>>)
+a| The HTTP proxy URL. This setting is optional.
+
+**Example**:
+
+[source,yaml]
+----
+http://proxy.mydomain.com:3128
+----
+
+| [[monitor-http-username]]**`username`**
+(<<synthetics-lightweight-data-string,string>>)
+a| The username for authenticating with the server. The credentials are passed with the request. This setting is optional.
+
+You need to specify credentials when your `check.response` settings require it. For example, you can check for a 403 response (`check.response.status: [403]`) without setting credentials.
+
+| [[monitor-http-password]]**`password`**
+(<<synthetics-lightweight-data-string,string>>)
+| The password for authenticating with the server. This setting is optional.
+
+| [[monitor-http-ssl]]**`ssl`**
+({heartbeat-ref}/configuration-ssl.html[SSL])
+a| The TLS/SSL connection settings for use with the HTTPS endpoint. If you don't specify settings, the system defaults are used.
+
+**Example**:
+
+[source,yaml]
+----
+- type: http
+  id: my-http-service
+  name: My HTTP Service
+  urls: "https://myhost:443"
+  schedule: '@every 5s'
+  ssl:
+    certificate_authorities: ['/etc/ca.crt']
+    supported_protocols: ["TLSv1.0", "TLSv1.1", "TLSv1.2"]
+----
+
+| [[monitor-http-headers]]**`headers`**
+(<<synthetics-lightweight-data-bool,boolean>>)
+a| Controls the indexing of the HTTP response headers `http.response.body.headers` field. Set `response.include_headers` to `false` to disable.
+
+**Default**: `true`
+
+| [[monitor-http-response]]**`response`**
+a| Controls the indexing of the HTTP response body contents to the `http.response.body.contents` field.
+
+**`include_body`** (`"on_error"`, `"never"`, or `"always"`)::
+Set `response.include_body` to one of the following:
++
+* `on_error`: Include the body if an error is encountered during the check. This is the default.
+* `never`: Never include the body.
+* `always`: Always include the body with checks.
+
+**`include_body_max_bytes`** (<<synthetics-lightweight-data-numbers,number>>)::
+Set `response.include_body_max_bytes` to control the maximum size of the stored body contents.
++
+**Default**: `1024`
+
+| [[monitor-http-check]]**`check`**
+a| **`request`**::
+An optional `request` to send to the remote host. Under `check.request`, specify these options:
++
+--
+**`method`** (`"HEAD"`, `"GET"`, `"POST"`, or `"OPTIONS"`):::
+The HTTP method to use.
+
+**`headers`** (https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers[HTTP headers]):::
+A dictionary of additional HTTP headers to send. By default Synthetics will set the 'User-Agent' header to identify itself.
+
+**`body`**  (<<synthetics-lightweight-data-string,string>>):::
+Optional request body content.
+--
++
+**Example**: This monitor POSTs an `x-www-form-urlencoded` string to the endpoint `/demo/add`.
++
+[source,yaml]
+----
+check.request:
+  method: POST
+  headers:
+    'Content-Type': 'application/x-www-form-urlencoded'
+  # urlencode the body:
+  body: "name=first&email=someemail%40someemailprovider.com"
+----
+
+**`response`**::
+The expected `response`.
++
+Under `check.response`, specify these options:
++
+**`status`** (list of <<synthetics-lightweight-data-string,string>>s):::
+A list of expected status codes. 4xx and 5xx codes are considered `down` by default. Other codes are considered `up`.
++
+**Example**:
++
+[source,yaml]
+----
+check.response:
+  status: [200, 201]
+----
+
+**`headers`** (https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers[HTTP headers]):::
+The required response headers.
+
+**`body.positive`** (list of <<synthetics-lightweight-data-string,string>>s):::
+A list of regular expressions to match the body output. Only a single expression needs to match.
++
+**Example**:
++
+This monitor examines the response body for the strings 'foo' or 'Foo':
++
+[source,yaml]
+----
+check.response:
+  status: [200, 201]
+  body:
+    positive:
+      - foo
+      - Foo
+----
+
+**`body.negative`** (list of <<synthetics-lightweight-data-string,string>>s):::
+A list of regular expressions to match the body output negatively. Return match failed if single expression matches. HTTP response bodies of up to 100MiB are supported.
++
+This monitor examines match successfully if there is no 'bar' or 'Bar' at all, examines match failed if there is 'bar' or 'Bar' in the response body:
++
+**Example**:
++
+[source,yaml]
+----
+check.response:
+  status: [200, 201]
+  body:
+    negative:
+      - bar
+      - Bar
+----
++
+**Example**:
++
+This monitor examines match successfully only when 'foo' or 'Foo' in body AND no 'bar' or 'Bar' in body:
++
+[source,yaml]
+----
+check.response:
+  status: [200, 201]
+  body:
+    positive:
+      - foo
+      - Foo
+    negative:
+      - bar
+      - Bar
+----
+
+**`json`**:::
+A list of expressions executed against the body when parsed as JSON.
+Body sizes must be less than or equal to 100 MiB.
++
+**`description`**::::
+A description of the check.
+
+**`expression`**::::
+The following configuration shows how to check the response using
+https://github.com/PaesslerAG/gval/blob/master/README.md[gval] expressions
+when the body contains JSON:
++
+**Example**:
++
+[source,yaml]
+----
+check.response:
+  status: [200]
+  json:
+    - description: check status
+      expression: 'foo.bar == "myValue"'
+----
+
+|===