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-tap-google-sheets
+# tap-google-sheets
+
+This is a [Singer](https://singer.io) tap that produces JSON-formatted data
+following the [Singer
+spec](https://github.com/singer-io/getting-started/blob/master/SPEC.md).
+
+This tap:
+
+- Pulls raw data from the [Google Sheets v4 API](https://developers.google.com/sheets/api)
+- Extracts the following endpoints:
+  - [Spreadsheet File](https://developers.google.com/drive/api/v3/reference/files/get)
+  - [Spreadsheet Metadata, Sheets, Headers](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/get)
+  - [Spreadsheet Values](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets.values/get)
+- For each Sheet:
+  - Outputs the schema for each resource (based on the column header and datatypes of first row of data)
+  - Outputs a record for all columns with column headers, and for each row of data until it reaches an empty row
+
+## API Endpoints
+[**file (GET)**](https://developers.google.com/drive/api/v3/reference/files/get)
+- Endpoint: https://www.googleapis.com/drive/v3/files/${spreadsheet_id}?fields=id,name,createdTime,modifiedTime,version
+- Primary keys: id
+- Replication strategy: Full (GET file audit data for spreadsheet_id in config)
+- Process/Transformations: Replicate Data if Modified
+
+[**metadata (GET)**](https://developers.google.com/drive/api/v3/reference/files/get)
+- Endpoint: https://sheets.googleapis.com/v4/spreadsheets/${spreadsheet_id}?includeGridData=true&ranges=1:2
+- This endpoint eturns spreadsheet metadata, sheet metadata, and value metadata (data type information)
+- Primary keys: spreadsheetId, title, field_name
+- Foreign keys: None
+- Replication strategy: Full (get and replace file metadata for spreadshee_id in config)
+- Process/Transformations:
+  - Verify Sheets: Check sheets exist (compared to catalog) and check gridProperties (available area)
+    - sheetId, title, index, gridProperties (rowCount, columnCount)
+  - Verify Field Headers (1st row): Check field headers exist (compared to catalog), missing headers (columns to skip), column order/position, and column uniqueness
+    - Header's field_name, position: data.rowData[0].values[i].formattedValue
+  - Create/Verify Datatypes (2nd row): 
+    - Row 2's datatype, format: data.rowData[1].values[i]
+      - First check:
+        - [effectiveValue: key](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/other#ExtendedValue)
+          - Valid types: numberValue, stringValue, boolValue
+          - Invalid types: formulaValue, errorValue
+      - Then check:
+        - [effectiveFormat.numberFormat.type](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/cells#NumberFormatType)
+          - Valid types: UNEPECIFIED, TEXT, NUMBER, PERCENT, CURRENCY, DATE, TIME, DATE_TIME, SCIENTIFIC
+          - If DATE or DATE_TIME, set JSON schema datatype = string and format = date-time
+        - [effectiveFormat.numberFormat.pattern](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/cells#NumberFormat)
+
+[**values (GET)**](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets.values/get)
+- Endpoint: https://sheets.googleapis.com/v4/spreadsheets/${spreadsheet_id}/values/'${sheet_name}'!${row_range}?dateTimeRenderOption=SERIAL_NUMBER&valueRenderOption=UNFORMATTED_VALUE&majorDimension=ROWS
+- This endpoint loops through sheets and row ranges to get the [unformatted values](https://developers.google.com/sheets/api/reference/rest/v4/ValueRenderOption) (effective values only), dates and datetimes as [serial numbers](https://developers.google.com/sheets/api/reference/rest/v4/DateTimeRenderOption)
+- Primary keys: row
+- Replication strategy: Full (GET file audit data for spreadsheet_id in config)
+- Process/Transformations:
+  - Loop through sheets (compared to catalog selection)
+    - Send metadata for sheet
+  - Loop through ranges of rows until reaching empty row or area max row (from sheet metadata)
+  - Transform values, if necessary (dates, date-times, boolean, integer, numers)
+  - Process/send records
+
+## Authentication
+The [**Google Sheets Setup & Authentication**](https://drive.google.com/open?id=1FojlvtLwS0-BzGS37R0jEXtwSHqSiO1Uw-7RKQQO-C4) Google Doc provides instructions show how to configure the Google Cloud API credentials to enable Google Drive and Google Sheets APIs, configure Google Cloud to authorize/verify your domain ownership, generate an API key (client_id, client_secret), authenticate and generate a refresh_token, and prepare your tap config.json with the necessary parameters.
+- Enable Googe Drive APIs and Authorization Scope: https://www.googleapis.com/auth/drive.metadata.readonly
+- Enable Google Sheets API and Authorization Scope: https://www.googleapis.com/auth/spreadsheets.readonly
+- Tap config.json parameters:
+  - client_id: identifies your application
+  - client_secret: authenticates your application
+  - refresh_token: generates an access token to authorize your session
+  - spreadsheet_id: unique identifier for each spreadsheet in Google Drive
+  - start_date: absolute minimum start date to check file modified
+  - user_agent: tap-name and email address; identifies your application in the Remote API server logs
+
+## Quick Start
+
+1. Install
+
+    Clone this repository, and then install using setup.py. We recommend using a virtualenv:
+
+    ```bash
+    > virtualenv -p python3 venv
+    > source venv/bin/activate
+    > python setup.py install
+    OR
+    > cd .../tap-google-sheets
+    > pip install .
+    ```
+2. Dependent libraries
+    The following dependent libraries were installed.
+    ```bash
+    > pip install target-json
+    > pip install target-stitch
+    > pip install singer-tools
+    > pip install singer-python
+    ```
+    - [singer-tools](https://github.com/singer-io/singer-tools)
+    - [target-stitch](https://github.com/singer-io/target-stitch)
+
+3. Create your tap's `config.json` file. Include the client_id, client_secret, refresh_token, site_urls (website URL properties in a comma delimited list; do not include the domain-level property in the list), start_date (UTC format), and user_agent (tap name with the api user email address).
+
+    ```json
+    {
+        "client_id": "YOUR_CLIENT_ID",
+        "client_secret": "YOUR_CLIENT_SECRET",
+        "refresh_token": "YOUR_REFRESH_TOKEN",
+        "spreadsheet_id": "YOUR_GOOGLE_SPREADSHEET_ID",
+        "start_date": "2019-01-01T00:00:00Z",
+        "user_agent": "tap-google-sheets <api_user_email@example.com>"
+    }
+    ```
+    
+    Optionally, also create a `state.json` file. `currently_syncing` is an optional attribute used for identifying the last object to be synced in case the job is interrupted mid-stream. The next run would begin where the last job left off.
+    Only the `performance_reports` uses a bookmark. The date-time bookmark is stored in a nested structure based on the endpoint, site, and sub_type.
+
+    ```json
+    {
+        "currently_syncing": "file_metadata",
+        "bookmarks": {
+            "file_metadata": "2019-09-27T22:34:39.000000Z",
+            "sheets_loaded": "2019-09-27T21:55:42.000000Z"
+        }
+    }
+    ```
+
+4. Run the Tap in Discovery Mode
+    This creates a catalog.json for selecting objects/fields to integrate:
+    ```bash
+    tap-google-sheets --config config.json --discover > catalog.json
+    ```
+   See the Singer docs on discovery mode
+   [here](https://github.com/singer-io/getting-started/blob/master/docs/DISCOVERY_MODE.md#discovery-mode).
+
+5. Run the Tap in Sync Mode (with catalog) and [write out to state file](https://github.com/singer-io/getting-started/blob/master/docs/RUNNING_AND_DEVELOPING.md#running-a-singer-tap-with-a-singer-target)
+
+    For Sync mode:
+    ```bash
+    > tap-google-sheets --config tap_config.json --catalog catalog.json > state.json
+    > tail -1 state.json > state.json.tmp && mv state.json.tmp state.json
+    ```
+    To load to json files to verify outputs:
+    ```bash
+    > tap-google-sheets --config tap_config.json --catalog catalog.json | target-json > state.json
+    > tail -1 state.json > state.json.tmp && mv state.json.tmp state.json
+    ```
+    To pseudo-load to [Stitch Import API](https://github.com/singer-io/target-stitch) with dry run:
+    ```bash
+    > tap-google-sheets --config tap_config.json --catalog catalog.json | target-stitch --config target_config.json --dry-run > state.json
+    > tail -1 state.json > state.json.tmp && mv state.json.tmp state.json
+    ```
+
+6. Test the Tap
+    
+    While developing the Google Search Console tap, the following utilities were run in accordance with Singer.io best practices:
+    Pylint to improve [code quality](https://github.com/singer-io/getting-started/blob/master/docs/BEST_PRACTICES.md#code-quality):
+    ```bash
+    > pylint tap_google_sheets -d missing-docstring -d logging-format-interpolation -d too-many-locals -d too-many-arguments
+    ```
+    Pylint test resulted in the following score:
+    ```bash
+    TBD
+    ```
+
+    To [check the tap](https://github.com/singer-io/singer-tools#singer-check-tap) and verify working:
+    ```bash
+    > tap-google-sheets --config tap_config.json --catalog catalog.json | singer-check-tap > state.json
+    > tail -1 state.json > state.json.tmp && mv state.json.tmp state.json
+    ```
+    Check tap resulted in the following:
+    ```bash
+    TBD
+    ```
+---
+
+Copyright &copy; 2019 Stitch