gctools/cognos7/mdl_convert.py

import json
from pathlib import Path
import re


CONVERSION = [
    "Name",
    "CognosSource",
    "CognosPackageDatasourceConnection",
    "DataSource",
    "OrgName",
    "Dimension",
    "Root",
    "Drill",
    "Levels",
    "Associations",
    "Category",
    "SpecialCategory",
    "MapDrills",
    "ViewName",
    "Measure",
    "Signon",
    "Cube",
    "CustomView",
    "CustomViewChildList",
    "SecurityNameSpace",
    "SecurityObject",
]

id_lookup = {}
find_words = re.compile(r'("[^"]+"|\w+) ')


def convert_block(block):
    block = block.replace("\n", "")
    block_type = block.split(" ")[0]

    words = find_words.findall(block)
    if len(words) < 3:
        return {"Type": block_type}
    result = {"Type": words[0], "ID": words[1], "Name": words[2].strip('"')}

    offset = 0
    for i in range(3, len(words), 2):
        if len(words) < i + offset + 2:
            break
        key = words[i + offset]
        if key in ["PackageReportSource", "Database"]:
            result[key] = {
                "ID": words[i + offset + 1],
                "Name": words[i + offset + 2].strip('"'),
            }
            offset += 1
        elif key in ["DimensionView"]:
            if key + "s" not in result:
                result[key + "s"] = []
            result[key + "s"].append(
                {"ID": words[i + offset + 1], "Name": words[i + offset + 2].strip('"')}
            )
            offset += 1
        elif key in ["MeasureInclude"]:
            if key + "s" not in result:
                result[key + "s"] = []
            result[key + "s"].append(
                {"ID": words[i + offset + 1], "Include": words[i + offset + 2]}
            )
            offset += 1
        elif key == "Calc":
            for j in range(i + offset + 1, len(words)):
                if words[j] in ["Sign", "Format", "Filtered"] or j == len(words) - 1:
                    result["Calc"] = " ".join(words[i + offset + 1 : j])
                    offset = j - i - 1
                    break  # for
        elif key == "EncryptedPW":
            result["EncryptedPW"] = words[i + offset + 1].strip('"')
            result["Salt"] = words[i + offset + 2].strip('"')
            offset += 1
        elif key == "AllocationAdd":
            if key + "s" not in result:
                result[key + "s"] = []
            result[key + "s"].append(
                {"Measure": words[i + offset + 2], "Type": words[i + offset + 4]}
            )
            offset += 3
        elif key in [
            "CustomViewList",
            "DrillThrough",
            "DeployLocations",
            "PowerCubeCustomViewList",
            "StartList",
            "TransientLevelList",
        ]:
            for j in range(i + offset + 1, len(words)):
                if words[j] in ["EndList"]:
                    result[key] = " ".join(words[i + offset + 1 : j])
                    offset = j - i - 1
                    break  # for
        # elif words[i + offset].isnumeric() or words[i + offset].startswith('"'):
        #    offset += 1
        else:
            result[key] = words[i + offset + 1].strip('"')

    if block_type == "DataSource":
        result["Columns"] = []
    if block_type in ["OrgName", "Levels", "Measure"]:
        result["Associations"] = []
    if block_type == "Dimension":
        result["Root"] = {}
        result["Levels"] = []
        result["Categories"] = []
        result["SpecialCategories"] = []
    if block_type == "Root":
        result["Drill"] = {}
    if block_type == "Associations":
        result["Parent"] = 0
    if block_type == "CustomView":
        result["ChildList"] = {}
    if block_type == "SecurityNameSpace":
        result["Objects"] = []

    return result


def remove_ids(nested):
    nested.pop("ID", "")
    nested.pop("DateDrill", "")
    nested.pop("Primary", "")
    nested.pop("Lastuse", "")
    nested.pop("AssociationContext", "")
    if (
        nested.get("Type", "") == "SpecialCategory"
        and "Label" in nested
        and "20" in nested["Label"]
    ):
        nested.pop("Label", "")

    for col in ["Parent", "Levels", "CustomViewList"]:
        if col not in nested:
            continue
        if col == "Levels" and (
            isinstance(nested["Levels"], list) or nested["Levels"] == "0"
        ):
            continue
        nested[col] = id_lookup.get(nested[col], {}).get("Name", "undefined")

    for child in nested.values():
        if isinstance(child, dict):
            remove_ids(child)
        if isinstance(child, list):
            for entry in child:
                remove_ids(entry)
    return nested


def prepare_mdl_str(mdl_str):
    mdl_str = re.sub(r"\n+", "\n", mdl_str)
    mdl_str = re.sub(r"^\n?Name ", "ModelName 1 ", mdl_str)
    mdl_str = re.sub(r'\nLevels (\d+ [^"])', r"Levels \1", mdl_str)
    mdl_str = re.sub(r" Associations ", " \nAssociations ", mdl_str)
    mdl_str = re.sub(r'([^ ])""', r"\1'", mdl_str)
    mdl_str = re.sub(r'""([^ ])', r"'\1", mdl_str)
    tags = "|".join(CONVERSION)
    mdl_str = re.sub(r"\n(" + tags + r") ", r"\n\n\1 ", mdl_str)
    return mdl_str


def group_mdl_blocks(converted):
    result = {
        "Model": {},
        "Connections": [],
        "DataSources": [],
        "Dimensions": [],
        "Measures": [],
        "Signons": [],
        "CustomViews": [],
        "Security": [],
        "Cubes": [],
    }
    types = [c["Type"] for c in converted]
    ids = [c.get("ID", "0") for c in converted]

    id_lookup.update(dict(zip(ids, converted)))

    current = None
    level_ids = []

    for c, t in zip(converted, types):
        if t in [""]:
            continue
        if (
            t in ["Category", "SpecialCategory"]
            and result["Dimensions"][-1]["Name"] == "Zeit"
        ):
            if t == "Category" or c["Name"][0].isnumeric():
                continue

        if t in ["ModelName"]:
            result["Model"] = c
        elif t in ["CognosSource", "CognosPackageDatasourceConnection"]:
            result["Connections"].append(c)
        elif t in ["DataSource"]:
            result["DataSources"].append(c)
        elif t in ["OrgName"]:
            result["DataSources"][-1]["Columns"].append(c)
        elif t in ["Dimension"]:
            level_ids = []
            result["Dimensions"].append(c)
        elif t in ["Root"]:
            result["Dimensions"][-1]["Root"] = c
        elif t in ["Drill"]:
            result["Dimensions"][-1]["Root"]["Drill"] = c
        elif t in ["Levels"]:
            current = c
            level_ids.append(c["ID"])
            result["Dimensions"][-1]["Levels"].append(c)
        elif t in ["Category"]:
            if c["Levels"] in level_ids[0:2]:
                result["Dimensions"][-1]["Categories"].append(c)
        elif t in ["SpecialCategory"]:
            result["Dimensions"][-1]["SpecialCategories"].append(c)
        elif t in ["Measure"]:
            current = c
            result["Measures"].append(c)
        elif t in ["Associations"]:
            c["Parent"] = current["ID"]
            current["Associations"].append(c)
            for ds in result["DataSources"]:
                for col in ds["Columns"]:
                    if col["Column"] == c["AssociationReferenced"]:
                        col["Associations"].append(c)
        elif t in ["Signon"]:
            result["Signons"].append(c)
        elif t in ["Cube"]:
            result["Cubes"].append(c)
        elif t in ["CustomView"]:
            result["CustomViews"].append(c)
        elif t in ["CustomViewChildList"]:
            for cv in result["CustomViews"]:
                if cv["ID"] == c["ID"]:
                    cv["ChildList"] = c
        elif t in ["SecurityNameSpace"]:
            result["Security"].append(c)
        elif t in ["SecurityObject"]:
            result["Security"][-1]["Objects"].append(c)
        # else:
        #     print(t, c)
    return result


def build_query(datasource):
    table = datasource["Name"]
    suffix = "_fm" if datasource["SourceType"] == "CognosSourceQuery" else "_imr"
    table_name = f"[staging].[{table}{suffix}]"
    view_name = f"[load].[{table}]"
    columns = ",\n    ".join([extract_column(c) for c in datasource["Columns"]])
    return f"CREATE VIEW {view_name}\nAS\nSELECT {columns} \nFROM {table_name}\nGO\n\n"


def extract_column(col):
    name = col["Name"]
    if "]." in name:
        name = name.split("].")[-1]
    alias = col["Column"]
    is_used = "" if len(col["Associations"]) > 0 else "--"
    return f'{is_used}{name} AS "{alias}"'


def convert_file(filename):
    with open(filename, "r", encoding="latin-1") as frh:
        mdl_str = frh.read()

    mdl_str = prepare_mdl_str(mdl_str)
    mdl_blocks = mdl_str.split("\n\n")

    converted = [convert_block(b) for b in mdl_blocks]

    grouped = group_mdl_blocks(converted)

    with open(filename[:-4] + "_ori.json", "w") as fwh:
        json.dump(grouped, fwh, indent=2)
    # yaml.safe_dump(result, open(filename[:-4] + ".yaml", "w"))

    without_ids = remove_ids(grouped)
    with open(filename[:-4] + ".json", "w") as fwh:
        json.dump(without_ids, fwh, indent=2)

    queries = [build_query(ds) for ds in grouped["DataSources"]]
    with open(filename[:-4] + "_queries.txt", "w", encoding="latin-1") as fwh:
        fwh.writelines(queries)


def convert_folder(base_dir):
    files = sorted([(f.stat().st_mtime, f) for f in Path(base_dir).rglob("*.mdl")])
    for timestamp, filename in files:
        convert_file(str(filename))


if __name__ == "__main__":
    # convert_file("data/S_Offene_Auftraege.mdl")
    # convert_file("data/F_Belege_SKR_SKR_Boettche.mdl")
    convert_folder("data/")