Bạn có thể thấy hữu ích khi chỉ trích xuất văn bản từ một tài liệu. Điều này rất hữu ích nếu bạn truyền văn bản sang một dịch vụ API khác. Tất cả văn bản trong tài liệu đều nằm trong chạy văn bản của các thành phần đoạn. Văn bản có thể xuất hiện ở 3 loại phần tử cấu trúc của tài liệu:
- Đoạn
- Mục lục
- Bảng
Bảng có thể được lồng trong một bảng khác. Do đó, để trích xuất tất cả văn bản trong một tài liệu, bạn phải truy cập vào từng phần tử cấu trúc lồng nhau.
Để xem mô tả đầy đủ về nội dung tài liệu, hãy xem hướng dẫn về Cấu trúc tài liệu.
Mẫu sau đây sử dụng đệ quy để truy cập từng thành phần cấu trúc trong tài liệu và in văn bản.
Java
// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.extensions.java6.auth.oauth2.AuthorizationCodeInstalledApp;
import com.google.api.client.extensions.jetty.auth.oauth2.LocalServerReceiver;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow;
import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets;
import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.client.util.store.FileDataStoreFactory;
import com.google.api.services.docs.v1.Docs;
import com.google.api.services.docs.v1.DocsScopes;
import com.google.api.services.docs.v1.model.Document;
import com.google.api.services.docs.v1.model.ParagraphElement;
import com.google.api.services.docs.v1.model.StructuralElement;
import com.google.api.services.docs.v1.model.TableCell;
import com.google.api.services.docs.v1.model.TableRow;
import com.google.api.services.docs.v1.model.TextRun;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.security.GeneralSecurityException;
import java.util.Collections;
import java.util.List;
public class ExtractText {
private static final String APPLICATION_NAME = "Google Docs API Extract Guide";
private static final JsonFactory JSON_FACTORY = JacksonFactory.getDefaultInstance();
private static final String TOKENS_DIRECTORY_PATH = "tokens";
private static final String DOCUMENT_ID = "YOUR_DOCUMENT_ID";
/**
* Global instance of the scopes required by this quickstart. If modifying these scopes, delete
* your previously saved tokens/ folder.
*/
private static final List<String> SCOPES =
Collections.singletonList(DocsScopes.DOCUMENTS_READONLY);
private static final String CREDENTIALS_FILE_PATH = "/credentials.json";
/**
* Creates an authorized Credential object.
*
* @param HTTP_TRANSPORT The network HTTP Transport.
* @return An authorized Credential object.
* @throws IOException If the credentials.json file cannot be found.
*/
private static Credential getCredentials(final NetHttpTransport HTTP_TRANSPORT)
throws IOException {
// Load client secrets.
InputStream in = ExtractText.class.getResourceAsStream(CREDENTIALS_FILE_PATH);
GoogleClientSecrets clientSecrets =
GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(in));
// Build flow and trigger user authorization request.
GoogleAuthorizationCodeFlow flow =
new GoogleAuthorizationCodeFlow.Builder(HTTP_TRANSPORT, JSON_FACTORY, clientSecrets, SCOPES)
.setDataStoreFactory(new FileDataStoreFactory(new java.io.File(TOKENS_DIRECTORY_PATH)))
.setAccessType("offline")
.build();
LocalServerReceiver receiver = new LocalServerReceiver.Builder().setPort(8888).build();
return new AuthorizationCodeInstalledApp(flow, receiver).authorize("user");
}
/**
* Returns the text in the given ParagraphElement.
*
* @param element a ParagraphElement from a Google Doc
*/
private static String readParagraphElement(ParagraphElement element) {
TextRun run = element.getTextRun();
if (run == null || run.getContent() == null) {
// The TextRun can be null if there is an inline object.
return "";
}
return run.getContent();
}
/**
* Recurses through a list of Structural Elements to read a document's text where text may be in
* nested elements.
*
* @param elements a list of Structural Elements
*/
private static String readStructuralElements(List<StructuralElement> elements) {
StringBuilder sb = new StringBuilder();
for (StructuralElement element : elements) {
if (element.getParagraph() != null) {
for (ParagraphElement paragraphElement : element.getParagraph().getElements()) {
sb.append(readParagraphElement(paragraphElement));
}
} else if (element.getTable() != null) {
// The text in table cells are in nested Structural Elements and tables may be
// nested.
for (TableRow row : element.getTable().getTableRows()) {
for (TableCell cell : row.getTableCells()) {
sb.append(readStructuralElements(cell.getContent()));
}
}
} else if (element.getTableOfContents() != null) {
// The text in the TOC is also in a Structural Element.
sb.append(readStructuralElements(element.getTableOfContents().getContent()));
}
}
return sb.toString();
}
public static void main(String... args) throws IOException, GeneralSecurityException {
// Build a new authorized API client service.
final NetHttpTransport HTTP_TRANSPORT = GoogleNetHttpTransport.newTrustedTransport();
Docs service =
new Docs.Builder(HTTP_TRANSPORT, JSON_FACTORY, getCredentials(HTTP_TRANSPORT))
.setApplicationName(APPLICATION_NAME)
.build();
Document doc = service.documents().get(DOCUMENT_ID).execute();
System.out.println(readStructuralElements(doc.getBody().getContent()));
}
}
Python
# Copyright 2019 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Recursively extracts the text from a Google Doc.
"""
import googleapiclient.discovery as discovery
from httplib2 import Http
from oauth2client import client
from oauth2client import file
from oauth2client import tools
SCOPES = 'https://www.googleapis.com/auth/documents.readonly'
DISCOVERY_DOC = 'https://docs.googleapis.com/$discovery/rest?version=v1'
DOCUMENT_ID = 'YOUR_DOCUMENT_ID'
def get_credentials():
"""Gets valid user credentials from storage.
If nothing has been stored, or if the stored credentials are invalid,
the OAuth 2.0 flow is completed to obtain the new credentials.
Returns:
Credentials, the obtained credential.
"""
store = file.Storage('token.json')
credentials = store.get()
if not credentials or credentials.invalid:
flow = client.flow_from_clientsecrets('credentials.json', SCOPES)
credentials = tools.run_flow(flow, store)
return credentials
def read_paragraph_element(element):
"""Returns the text in the given ParagraphElement.
Args:
element: a ParagraphElement from a Google Doc.
"""
text_run = element.get('textRun')
if not text_run:
return ''
return text_run.get('content')
def read_structural_elements(elements):
"""Recurses through a list of Structural Elements to read a document's text where text may be
in nested elements.
Args:
elements: a list of Structural Elements.
"""
text = ''
for value in elements:
if 'paragraph' in value:
elements = value.get('paragraph').get('elements')
for elem in elements:
text += read_paragraph_element(elem)
elif 'table' in value:
# The text in table cells are in nested Structural Elements and tables may be
# nested.
table = value.get('table')
for row in table.get('tableRows'):
cells = row.get('tableCells')
for cell in cells:
text += read_structural_elements(cell.get('content'))
elif 'tableOfContents' in value:
# The text in the TOC is also in a Structural Element.
toc = value.get('tableOfContents')
text += read_structural_elements(toc.get('content'))
return text
def main():
"""Uses the Docs API to print out the text of a document."""
credentials = get_credentials()
http = credentials.authorize(Http())
docs_service = discovery.build(
'docs', 'v1', http=http, discoveryServiceUrl=DISCOVERY_DOC)
doc = docs_service.documents().get(documentId=DOCUMENT_ID).execute()
doc_content = doc.get('body').get('content')
print(read_structural_elements(doc_content))
if __name__ == '__main__':
main()