Parsing#

Concourse Tools contains a number of simple functions for mapping between Python and the Concourse resource type paradigm.

JSON Parsing#

The following functions are responsible for parsing Concourse JSON payloads and returning Python objects.

concoursetools.parsing.parse_check_payload(raw_json)[source]#

Parse raw input JSON for a check payload.

Parameters:: raw_json (str) – A JSON string of the following form:

{
    "source": {
        "uri": "git://some-uri",
        "branch": "develop",
        "private_key": "..."
    },
    "version": { "ref": "61cbef" }
}

Return type:: Tuple[Dict[str, Any], Optional[Dict[str, str]]]
Returns:: The source and version configuration (if it exists).

Note

If the version has not been passed, then None will be returned, and not an empty dict.

concoursetools.parsing.parse_in_payload(raw_json)[source]#

Parse raw input JSON for an in payload.

Parameters:: raw_json (str) – A JSON string of the following form:

{
    "source": {
        "uri": "git://some-uri",
        "branch": "develop",
        "private_key": "..."
    },
    "version": { "ref": "61cbef" },
    "params": { "skip_download": true }
}

Return type:: Tuple[Dict[str, Any], Dict[str, str], Dict[str, Any]]
Returns:: The source and version configuration, and parameters passed to the get step.

concoursetools.parsing.parse_out_payload(raw_json)[source]#

Parse raw input JSON for an out payload.

Parameters:: raw_json (str) – A JSON string of the following form:

{
    "params": {
        "branch": "develop",
        "repo": "some-repo"
    },
    "source": {
        "uri": "git@...",
        "private_key": "..."
    }
}

Return type:: Tuple[Dict[str, Any], Dict[str, Any]]
Returns:: The source configuration, and parameters passed to the put step.

concoursetools.parsing.parse_metadata(metadata_pairs)[source]#

Convert key-value pairs toa key-value mapping.

Parameters:: metadata_pairs (List[Dict[Literal['name', 'value'], str]]) – A list of key-value pairs for processing in Concourse.
Return type:: Dict[str, str]
Returns:: A key-value mapping representing metadata.

JSON Formatting#

The following functions are responsible for formatting Concourse JSON payloads from Python objects.

concoursetools.parsing.format_check_output(version_configs, **json_kwargs)[source]#

Format check output as a JSON string.

Parameters:

version_configs (List[Dict[str, str]]) – A list of version configurations.
json_kwargs (Any) – Additional keyword arguments to pass to json.dumps().

Return type:

str

Returns:

A formatted JSON string to pass to Concourse, in the following form:

[
    { "ref": "61cbef" },
    { "ref": "d74e01" },
    { "ref": "7154fe" }
]

concoursetools.parsing.format_in_out_output(version_config, metadata, **json_kwargs)[source]#

Format in output or out output as a JSON string.

Parameters:

version_config (Dict[str, str]) – A version configuration.
metadata (Dict[str, str]) – A key-value mapping of metadata.
json_kwargs (Any) – Additional keyword arguments to pass to json.dumps().

Return type:

str

Returns:

A formatted JSON string to pass to Concourse, in the following form:

{
    "version": { "ref": "61cbef" },
    "metadata": [
        { "name": "commit", "value": "61cbef" },
        { "name": "author", "value": "Hulk Hogan" }
    ]
}

concoursetools.parsing.format_metadata(metadata)[source]#

Convert a key-value mapping to key-value pairs.

Parameters:: metadata (Dict[str, str]) – A key-value mapping representing metadata. Keys and values should both be strings.
Return type:: List[Dict[Literal['name', 'value'], str]]
Returns:: A list of key-value pairs for processing in Concourse.