tree-sitter-alloy

A grammar for the Grafana Alloy configuration language, supports all types and most commom uses of the language.

Showcase

Example

It can parse the following config which is on the Alloy configuration syntax docs page:

// Collection: mount a local directory with a certain path spec
local.file_match "applogs" {
    path_targets = [{"__path__" = "/tmp/app-logs/app.log"}]
}

// Collection: Take the file match as input, and scrape those mounted log files
loki.source.file "local_files" {
    targets    = local.file_match.applogs.targets

    // This specifies which component should process the logs next, the "link in the chain"
    forward_to = [loki.process.add_new_label.receiver]
}

// Transformation: pull some data out of the log message, and turn it into a label
loki.process "add_new_label" {
    stage.logfmt {
        mapping = {
            "extracted_level" = "level",
        }
    }

    // Add the value of "extracted_level" from the extracted map as a "level" label
    stage.labels {
        values = {
            "level" = "extracted_level",
        }
    }

    // The next link in the chain is the local_loki "receiver" (receives the telemetry)
    forward_to = [loki.write.local_loki.receiver]
}

// Anything that comes into this component gets written to the loki remote API
loki.write "local_loki" {
    endpoint {
        url = "http://loki:3100/loki/api/v1/push"
    }
}

Will be parsed into this AST:

(source_file [1, 0] - [39, 0]
  (comment [1, 0] - [1, 63])
  (block [2, 0] - [4, 1]
    name: (identifier [2, 0] - [2, 16])
    label: (string [2, 17] - [2, 26])
    (attribute [3, 4] - [3, 59]
      name: (identifier [3, 4] - [3, 16])
      value: (expression [3, 19] - [3, 59]
        (array [3, 19] - [3, 59]
          (expression [3, 20] - [3, 58]
            (object [3, 20] - [3, 58]
              (attribute [3, 21] - [3, 57]
                name: (string [3, 21] - [3, 31])
                value: (expression [3, 34] - [3, 57]
                  (string [3, 34] - [3, 57])))))))))
  (comment [6, 0] - [6, 79])
  (block [7, 0] - [12, 1]
    name: (identifier [7, 0] - [7, 16])
    label: (string [7, 17] - [7, 30])
    (attribute [8, 4] - [8, 49]
      name: (identifier [8, 4] - [8, 11])
      value: (expression [8, 17] - [8, 49]
        (identifier [8, 17] - [8, 49])))
    (comment [10, 4] - [10, 91])
    (attribute [11, 4] - [11, 54]
      name: (identifier [11, 4] - [11, 14])
      value: (expression [11, 17] - [11, 54]
        (array [11, 17] - [11, 54]
          (expression [11, 18] - [11, 53]
            (identifier [11, 18] - [11, 53]))))))
  (comment [14, 0] - [14, 82])
  (block [15, 0] - [31, 1]
    name: (identifier [15, 0] - [15, 12])
    label: (string [15, 13] - [15, 28])
    (block [16, 4] - [20, 5]
      name: (identifier [16, 4] - [16, 16])
      (attribute [17, 8] - [19, 9]
        name: (identifier [17, 8] - [17, 15])
        value: (expression [17, 18] - [19, 9]
          (object [17, 18] - [19, 9]
            (attribute [18, 12] - [18, 39]
              name: (string [18, 12] - [18, 29])
              value: (expression [18, 32] - [18, 39]
                (string [18, 32] - [18, 39])))))))
    (comment [22, 4] - [22, 83])
    (block [23, 4] - [27, 5]
      name: (identifier [23, 4] - [23, 16])
      (attribute [24, 8] - [26, 9]
        name: (identifier [24, 8] - [24, 14])
        value: (expression [24, 17] - [26, 9]
          (object [24, 17] - [26, 9]
            (attribute [25, 12] - [25, 39]
              name: (string [25, 12] - [25, 19])
              value: (expression [25, 22] - [25, 39]
                (string [25, 22] - [25, 39])))))))
    (comment [29, 4] - [29, 87])
    (attribute [30, 4] - [30, 49]
      name: (identifier [30, 4] - [30, 14])
      value: (expression [30, 17] - [30, 49]
        (array [30, 17] - [30, 49]
          (expression [30, 18] - [30, 48]
            (identifier [30, 18] - [30, 48]))))))
  (comment [33, 0] - [33, 78])
  (block [34, 0] - [38, 1]
    name: (identifier [34, 0] - [34, 10])
    label: (string [34, 11] - [34, 23])
    (block [35, 4] - [37, 5]
      name: (identifier [35, 4] - [35, 12])
      (attribute [36, 8] - [36, 49]
        name: (identifier [36, 8] - [36, 11])
        value: (expression [36, 14] - [36, 49]
          (string [36, 14] - [36, 49]))))))